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Perspectives in Psychiatric Care
ISSN 0031-5990
The Effects of Depressive Symptoms on Quality of Life Among Institutionalized Older Adults in Taiwan I-chuan Li, PhD, Huai-Ting Kuo, MSN, Kuan-Chia Lin, PhD, and Yi-Chen Wu, MSN I-chuan Li, PhD, is a Professor, Institute of Clinical and Community Health Nursing, National Yang-Ming University, Taipei, Taiwan; Huai-Ting Kuo, MSN, is a Doctoral Student, Department and Institute of Nursing, National Yang-Ming University, Taipei, Taiwan; Kuan-Chia Lin, PhD, is a Professor, Department of Health Care Management, National Taipei University of Nursing and Health Sciences, Taipei, Taiwan; and Yi-Chen Wu, MSN, is a Nursing Clinical Preceptor, Department of Gerontological Care and Management, Chang Gung University of Science and Technology, Taoyuan, Taiwan.
Search terms: Depressive symptoms, mediating factors, quality of life Author contact: [email protected], with a copy to the Editor: [email protected] Conflict of Interest Statement There is no conflict of interests for all authors. First Received October 25, 2012; Final Revision received April 14, 2013; Accepted for publication April 23, 2013.
PURPOSE: To explore the effect of physical health status and depressive symptoms on quality of life (QOL) and to examine whether depressive symptoms mediate the effect of physical health status on the physical and mental components of QOL among institutionalized older adults. DESIGN AND METHODS: A cross-sectional study was used to assess 306 residents from 73 long-term care facilities in Taipei, Taiwan. FINDINGS: We found that depressive symptoms mediated the relationship between the number of chronic diseases and activities of daily living and physical components of QOL (z = −2.41, p = .016; z = 3.33, p < .001) as well as between the number of chronic diseases and mental components of QOL (z = −2.45, p = .014). PRACTICE IMPLICATIONS: Our findings indicate that alleviating depressive symptoms can improve the QOL of older adults in long-term care facilities.
doi: 10.1111/ppc.12029
Background The proportion of older people is increasing in Western countries and in Taiwan. The percentage of the elderly population, defined as the population of people aged 65 and over, increased from 7.0% in 1993 to 10.4% in 2008 (Ministry of the Interior [MOI], 2008). It is projected that by 2025, approximately 20% of Taiwan’s population will be 65 years of age or older (Council for Economic Planning and Development [CEPD], 2008). This has resulted in a steadily increasing demand for long-term care (LTC) services in Taiwan. By 2015, the percentage of older people in need of LTC will be about 10.83% (MOI, 2008). Approximately 20.0% of Taiwan’s older adult population who requires assistance with activities of daily living (ADLs) receives LTC services (CEPD, 2009).This finding may partially explain the increase in the number of registered LTC facilities from 70 in 1997 to 1,064 in 2011 (MOI, 2013). Quality of life (QOL) is defined as an individual’s overall satisfaction with life and general sense of well-being (Huang, Wu, & Frangakis, 2006). Patient-reported outcomes are often used to measure QOL, a term which is used interchangeably with health-related quality of life (HRQOL), health status, and subjective well-being. According to Andersen, WittrupJensen, Lolk, Andersen, and Kragh-Sørensen (2004), measures of HRQOL are important for evaluating disability and 58
predicting mortality of frail people of advanced age. Thus, the regular monitoring of QOL is important. Although measurement of QOL has become a major focus of significant importance in clinical studies, very little attention has been paid to QOL of older persons in LTC facilities (Chang et al., 2010). QOL is a multidimensional concept (Gilhooly, Gilhooly, & Bowling, 2005), and different factors may have an impact on both physical and mental components of QOL. Identifying factors that influence those components of QOL in the elderly is important to provide direction and to make policies for improving QOL in institutionalized older persons. Depression has a significant impact on QOL. Studies have shown that elderly persons with depression are at high risk of having poor QOL (Chang & Chueh, 2011; Lin, Yen, & Fetzer, 2008) regardless of whether they are living in an LTC facility or living alone. Studies conducted in Taiwan have shown that the likelihood of developing depressive symptoms increased in proportion to the number of chronic diseases in institutionalized elderly individuals (Chang & Chueh, 2011; Huang, Dong, Lu, Yue, & Liu, 2010). The number of chronic diseases can be a significant predictor of depression. Andersen et al. (2004) found that the inability to independently perform ADL was the major factor affecting QOL. According to Salguero, Martínez-García, Molinero, and Márquez (2011), decreased mobility in older people impacts Perspectives in Psychiatric Care 50 (2014) 58–64 © 2013 Wiley Periodicals, Inc.
The Effects of Depressive Symptoms on Quality of Life Among Institutionalized Older Adults in Taiwan
QOL. There was one domestic study found that daily activities, physical symptoms, chronic diseases, physical performance, educational levels, and the number of caregivers have significant impacts on QOL (Lai et al., 2005). There is growing evidence that physical activity improves HRQOL by enhancing psychological well-being (Shibata, Oka, Nakamura, & Muraoka, 2007). The amount of food intake has been shown to be a significant predictor of depressive symptoms and QOL.According to Watson, Allen, Fursland, Byrne, and Nathan (2012),treatment of eating disorders can improve patients’ depression symptoms. Individuals with eating disorders experience poorer QOL compared with healthy individuals and those with serious physical illnesses (Jenkins, Hoste, Meyer, & Blissett, 2011). QOL is clearly impaired in individuals with eating disorders (Jenkins et al., 2011). QOL is clearly impaired in individuals with eating disorders.Thus,variability in food intake is known to relate to depressive symptom and QOL. However, to the best of our knowledge, the interactions among physical health status, depressive symptoms, and different aspects of physical and mental components of QOL in older adults who reside in LTC institutions have not been tested. Whether depressive symptoms mediate the effect of physical health status on physical and mental components of QOL has yet to be explored.In the present study,we were interested in understanding the relationships among physical health status, including the number of chronic diseases and ADLs, depressive symptoms, and QOL; therefore, variables such as educational level and the number of caregivers were not included in the mediation testing of QOL. This study tested whether depressive symptoms mediate the effect of physical health status, including ADL and the number of chronic diseases, on the physical and mental components of QOL in institutionalized elderly individuals in Taiwan. According to Judd and Kenny (2010), the conclusions from a mediation analysis are valid only if the causal assumptions are valid. The amount of food intake has been shown to be a significant predictor of depressive symptoms and QOL (Jenkins et al., 2011; Watson et al., 2012). Thus, we treated variability in food intake as an instrumental variable (IV) by measuring the number of full meals eaten during the past 3 months. Methods Design and Research Subjects Inclusion criteria of sampling included a healthy cognition status, which was tested by the Short Portable Mental Status Questionnaire (SPMSQ), and the ability to verbally communicate. Residents with SPMSQ scores < 8, indicating cognitive impairment, were excluded. Thus, those who have intact cognitive function were research subjects in this study. We Perspectives in Psychiatric Care 50 (2014) 58–64 © 2013 Wiley Periodicals, Inc.
received a list of community-based LTC facilities from the Department of Social Welfare in Taipei. In Taipei, a total of 307 registered facilities had a total of 10,647 beds. After we explained the aims of this study to the administrators of the facilities, 73 facilities agreed to participate. These facilities represented approximately 24% of the LTC facilities in this area. A total of 3,577 residents were being cared for at the 73 facilities, and 321 of those met the inclusion criteria for this study, representing approximately 9% of all residents with intact cognitive function. The participation rate in this study was 95% among qualified older residents. Between 1 and 11 participants from each facility participated in this study, with an average of 4.3 participants at each facility. Thus, overrepresentation by any one institution was not an issue. Study Instruments SPMSQ was used to assess residents’ cognitive functions (Pfeiffer, 1975). The assessment includes 10 questions divided among four domains: orientation (3 items), personal history (3 items), remote memory (3 items), and calculation (1 item). Scores ranging from 0 to 2 indicate severe cognitive impairment, those ranging from 3 to 5 indicate moderate cognitive impairment, scores ranging from 6 to 7 indicate mild cognitive impairment, and scores ranging from 8 to 10 indicate intact cognitive function. ADL scores were determined using the modified Barthel Index, which consists of 10 items: feeding, bathing, dressing, personal hygiene, toilet ability, bowel control, bladder control, transfer (from bed to chair and back), walking, and going up and down stairs. Total scores range from 0 to 100, with higher scores indicating greater independence: 0–20 indicates total dependence, 21–60 indicates severe dependence, 61–90 indicates moderate dependence, 91–99 indicates slight dependency, and 100 indicates functional independence. Depressive symptoms were evaluated using the short form of the Geriatric Depression Scale (GDS-SF). Subjects replied to a series of questions with either a “yes” (1) or a “no” (0) answer to describe their feelings during the previous 2 weeks. The GDS-SF includes 15 items with scores ranging from 0 to 15; a score ranging from 0 to 4 indicates no depressive symptoms; scores ranging from 5 to 9 represent possible clinical depressive symptoms; and scores ranging from 10 to 15 indicate severe depressive symptoms (Lee et al., 1993). HRQOL is based on subjective attitudes and experiences of physical, social, and mental health (Borgaonkar & Irvine, 2000). In this study, we measured QOL with the Taiwan version of the short form, which comprises 36 items (SF-36). The SF-36 includes 36 questions that cover eight domains: physical functioning, role limitation due to physical function, bodily pain, general health, vitality, social functioning, role limitation due to emotional problems, and mental health. The eight domains were grouped into a physical component 59
The Effects of Depressive Symptoms on Quality of Life Among Institutionalized Older Adults in Taiwan
summary and a mental component summary, which represent subjective physical health and mental health, respectively. The response scores for each dimension were summed, and the total was standardized and converted to a score ranging from 0 to 100. A higher score indicated higher levels of perceived QOL (Ware, 2005). Data Collection Data on ADL, GDS-SF, and SF-36 were collected from August 2008 to May 2009 by one well-trained investigator. The investigator, a graduate nursing student who is a highly experienced LTC nurse with 4 years of work experience at a teaching hospital, conducted all of the resident interviews. This investigator was trained by the study’s principal investigator, and the inter-rater reliability was above 0.90 for the SPMSQ, ADL, GDS-SF scores, and SF-36 scores. The investigator used the SPMSQ to screen all of the target residents to select those with intact cognitive function in order to assess the participants’ depressive symptoms and QOL. The facility nurses provided the investigator with information regarding daily routines related to the estimation of the amount of food eaten. Socio-demographic characteristics, ADL status, and medical diagnoses were retrieved by the investigator from the existing records of the 306 participating residents. Ethical Consideration This study was approved by the Institutional Review Board of the Yang-Ming University in Taipei. All participants in the study participated voluntarily and provided informed consent. Potential subjects were free to decline during the process of this study without any repercussion. Human rights and privacy of participants were protected. Confidentiality during the entire study was maintained using numerical identifiers on recorded data. Data Analysis A multiple hierarchical regression analysis was used to understand which of the demographic characteristics, variables of physical health status, and depressive symptoms are predictive of the physical and mental components of QOL. The variables that were statistically significant after performing the association analyses were entered into the regression analysis. The Sobel’s significance test was used to test whether physical health status and depressive symptoms have an impact on QOL (Sobel, 1982). This test is best explained with the aid of a simple model. The first step tested the association between the independent variable (physical health status) and the outcome/dependent variable (QOL). The second step tested the association between the independent variable (physical health status) and the mediator (depressive symptoms). The 60
third step tested the model with both the independent variable and the mediator predicting the outcome variable, demonstrating that the mediator was associated with the outcome variable in this multiple regression model. The path between the independent variable and the outcome/dependent variable was also tested to determine whether this was reduced to zero (total mediation) or reduced by a significant amount (partial mediation) (Dudley, Benuzillo, & Carrico, 2004). For all tests, results with p values less than .05 (two tailed) were considered statistically significant. In order to avoid violating the multicollinearity assumptions between depressive symptoms and QOL, there must be an IV that is known to relate to depressive symptom and QOL (Smith, 1982). Both the mediator and the outcome variables are treated as outcome variables, and they each may mediate the effect of the other. IV regression in the form of two-stage least squares (2SLS) was used to address the participants’ endogenous choices of some of our variables, such as depressive symptoms. In this study, we treated variability in food intake as an IV by measuring the number of full meals eaten during the past 3 months. Validity and Reliability The Chinese version of the ADL scale was developed by Shah, Vanclay, and Cooper (1989) from the original Barthel Index by modifying the scoring method to increase test sensitivity. The Chinese version of the GDS-SF has an internal consistency reliability of 0.89, a test–retest reliability of 0.85, a criterion-related validity of 0.95, and a concurrent validity of 0.96 (Chan, 1996). The SF-36 has been shown to have good reliability and validity in a general population in Taiwan (Lu, Tseng, & Tsai, 2003; Tseng, Lu, & Tsai, 2003). Cronbach’s alpha coefficients for the eight subscales of the SF-36 Taiwan version have been reported as 0.91, 0.92, 0.76, 0.82, 0.79, 0.65, 0.87, and 0.78, respectively (Lu et al., 2003). In this study, the Cronbach’s alpha was greater than 0.70 for all subscales (range 0.70–0.98). Results Characteristics of the Study Subjects In total, 306 subjects completed this study. As shown in Table 1, the age range was 65.08–96.58 years (mean age = 80.62, SD = 7.14) and the mean number of chronic diseases was 2.56 (SD = 1.21). The mean functional status score was 61.29 (SD = 31.92). Approximately 33% of the subjects had Barthel Index scores ranging from 61 to 90, indicating that they were moderately functionally dependent. Assessment of Depressive Symptoms and QOL The mean GDS-SF score was 5.85 (SD = 4.23). In addition, half of the participants (n = 166, 54.25%) had GDS-SF scores Perspectives in Psychiatric Care 50 (2014) 58–64 © 2013 Wiley Periodicals, Inc.
The Effects of Depressive Symptoms on Quality of Life Among Institutionalized Older Adults in Taiwan
Table 1. Characteristics of Participating Subjects (n = 306)
Variables
Mean (SD)
Gender Male Female Age (years) 65–74 75–84 ≥ 85 Educational levels (years) None 1–6 ≥7 Marital status With spouse Without spouse Financial support Family Nonfamily Number of chronic disease 0–2 ≥3 Whether taking medicines No Yes ADLs Total dependency Severe dependency Moderate dependency Slight dependency Independency GDS-SF score Normal (0–4) Depressive symptoms (5–9) Depression (10–15) QOL PCS MCS
Range
n (%) 160 (52.29) 146 (47.71)
80.62 (7.14)
65.08–96.58 71 (23.20) 146 (47.71) 89 (29.08) 80 (26.14) 118 (38.56) 108 (35.29) 85 (27.78) 221 (72.22) 215 (70.26) 91 (29.74)
2.56 (1.21)
0–7 153 (50.00) 153 (50.00) 10 (3.27) 296 (96.73)
61.29 (31.92)
0–100 58 83 100 32 33
5.85 (4.23)
(18.95) (27.12) (32.68) (10.46) (10.78)
0–15 135 (44.12) 90 (29.41) 76 (24.84)
37.20 (11.27) 51.39 (12.75)
6.93–64.93 16.85–75.97
Notes: SD, standard deviation; ADLs, activities of daily living; GDS-SF, Geriatric Depression Scaleshort form; QOL, quality of life; PCS, physical component summary; MCS, mental component summary.
of 5 or greater, indicating that they require further evaluation by a psychiatric specialist. Among the different QOL domains, bodily pain yielded the highest score (M = 79.15, SD = 27.74), while physical functioning (M = 28.96, SD = 29.27) yielded the lowest score. The Relationship Among Physical Health Status, Depressive Symptoms, and QOL We found that participants with fewer chronic diseases, higher ADL scores, and lower GDS-SF scores had significantly higher scores of the physical components of the QOL score (r = −.14, p = .014; r = .50, p < .001; and r = −.35, p < .001, respectively) (Table 2). The number of chronic diseases (r = −.18, p < .002) and GDS-SF scores (r = −.69, p < .001) is significantly Perspectives in Psychiatric Care 50 (2014) 58–64 © 2013 Wiley Periodicals, Inc.
correlated with mental components of the QOL score (Table 2). Multiple hierarchical regression analysis was used to understand which of the demographic characteristics, variables of physical health status, and depressive symptoms preTable 2. Correlation Between Demographics, Depressive Symptoms, and QOL (n = 306) Variable
PCS
MCS
Age Number of chronic disease ADL score GDS-SF score
0.07 −0.14* 0.50*** −0.35***
−0.04 −0.18** 0.06 −0.69***
Notes: *p < .05, **p < .01, ***p < .001. ADL, activity of daily living; QOL, quality of life; GDS-SF, Geriatric Depression Scale-short form; PCS, physical component summary; MCS, mental component summary.
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Table 3. Hierarchical Multiple Regression Explaining the Relationships of Health Status and GDS With QOL PCS
MCS
OLS
2SLS
OLS
2SLS
Variable
Coefficients (SE)
Coefficients (SE)
Coefficients (SE)
Coefficients (SE)
ADL score Number of chronic disease GDS-SF score Gender: Male
0.176*** (0.018) −1.302* (0.529) −1.066*** (0.164) 2.030 (1.293)
0.177*** (0.018) −1.304* (0.529) −1.078*** (0.165) 2.036 (1.295)
0.023 (0.023) −1.898** (0.594) −2.351*** (0.143) 3.827** (1.452)
0.020 (0.023) −1.911** (0.593) −2.356*** (0.144) 3.877** (1.450)
Notes: *p < .05, **p < .01, ***p < .001. OLS, ordinary least squares; 2SLS, two-stage least squares; PCS, physical component summary; MCS, mental component summary; GDS, Geriatric Depression Scale; QOL, quality of life; ADL, activity of daily living; GDS-SF, Geriatric Depression Scale-short form; SE, standard error.
dicted the physical component of QOL and the mental component of QOL. 2SLS regression analysis has been applied to replace the standard ordinary least squares analysis (Table 3). In the first stage of this IV-2SLS estimation, we obtained the predicted probability of depressive symptoms for each individual in the sample using IVs. The predicted probability of depressive symptoms was then used as a regressor in the main model of QOL, replacing the endogenous variable of depressive symptoms that is potentially correlated with the error term in the regression equation. Results of 2SLS showed that the IV significantly predicted depressive symptoms (p = .003) and the physical and mental components of QOL (p = .001 and p < .001, respectively), implying that the mediation test can be considered (Table 3). The variables that were statistically significant after performing the association analyses were entered into the regression analysis. The variables of ADLs and GDS-SF scores were significant predictors of the physical component of QOL (R2
= .37, F = 50.46, p < .001). In addition, the number of chronic disease and GDS-SF scores was a significant predictor of the mental component of QOL (R2 = .49, F = 91.60, p < .001). The results of the Sobel test showed that depressive symptoms mediated the effects of ADLs on the physical components of QOL (standardized β = 0.16, Sobel test z = 3.33, p < .001) to a degree of 11.11%. Depressive symptoms significantly mediated 40% and 53.68% of the effect of the number of chronic diseases on the physical and mental components of QOL, respectively (z = −2.41, p = .016 and z = −2.45, p = .014, respectively) (Table 4). Discussion The QOL scores in this study were much lower than those reported in a similar study conducted in Taiwanese nursing homes (Tseng & Wang, 2001). In addition, scores for three of the eight domains of the SF-36 (physical functioning,
Table 4. Regression Models and Sobel’s Test
Model Model 1: Depressive symptoms mediate the ADLs → PCS link ADLs → PCS Depressive symptoms → PCS ADLs → depressive symptoms ADLs → PCS | depressive symptoms Model 2: Depressive symptoms mediate the number of chronic disease → PCS link Number of chronic disease → PCS Depressive symptoms → PCS Number of chronic disease → depressive symptoms Number of chronic disease → PCS | depressive symptoms Model 3: Depressive symptoms mediate the number of chronic disease → MCS link Number of chronic disease → MCS Depressive symptoms → MCS Number of chronic disease → depressive symptoms Number of chronic disease → MCS | depressive symptoms
Regression test
Sobel’s test with Bootstrap methoda
B
SE
p
Indirect value
0.18 −1.07 −0.03 0.16
0.02 0.16 0.01 0.02
< .001 < .001 < .001 < .001
0.02
0.01 ∼ 0.03
11.11
−1.30 −1.07 0.44 0.33
0.53 0.16 0.18 0.17
.014 < .00 .012 .047
−0.52
−0.97 ∼ −0.09
40.00
−1.90 −2.35 0.44 −0.85
0.59 0.14 0.18 0.44
.002 < .00 .012 .053
−1.02
−1.86 ∼ −0.19
53.68
95% CI
Mediation (%)
Notes: ADLs, activities of daily living; PCS, physical component summary; MCS, mental component summary; SE, standard error; CI, confidence interval. a Using Bootstrap method to derive a confidence interval for indirect value.
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The Effects of Depressive Symptoms on Quality of Life Among Institutionalized Older Adults in Taiwan
social functioning, and mental health) were significantly lower in the study sample than in the general population of older Taiwanese individuals (Lu et al., 2003). The participants in the present study had an average of 2.56 chronic diseases, which was shown to be a significant predictor of the mental component of QOL. Institutionalized elderly with two or more chronic diseases have been shown to be at higher risk of having a poor mental component of QOL (Lai et al., 2005). The existence of chronic diseases correlated with one’s vitality, poorer social functioning, and role limitation, and caused emotional and mental health problems (Scuteri et al., 2011). In this study, ADL status was a significant predictor of the physical component of QOL. This finding is consistent with that reported by Tseng and Wang (2001). ADL is a global measurement that describes functional status in the elderly and reflects certain levels of dependence, disease severity, and resource consumption (Andersen et al., 2004). Residents with poorer ADLs should be monitored closely for the physical component of QOL. We know of no other studies that evaluated the physical health status-depressive symptoms-QOL mediation chain by testing the differential effects on the physical and mental components of QOL independently. Our study has shown that depressive symptoms are an important mediator between health status and impaired QOL among institutionalized elders. Although the number of chronic diseases cannot be changed, we can alleviate depressive symptoms and subsequently improve QOL. Thus, it is necessary to develop strategies to alleviate depressive symptoms in order to improve the mental component of QOL of institutionalized people of advanced age. The assessment of depressive symptoms in institutionalized older adults is important for early intervention and prevention, which may contribute to improvements in physical and mental components of QOL.
Implications for Nursing Practice Depressive symptoms determined by the GDS-SF had a negative relationship with the physical and mental components of QOL among older institutionalized Taiwanese. Therefore, healthcare professionals can improve the physical and mental components of QOL of residents of LTC facilities by treating depressive symptoms. It is necessary to conduct intervention trials to see whether they would improve depressive symptoms and to examine the effect of a reduction in depressive symptoms on QOL in a future study. It is important to monitor depressive symptoms regularly in order to improve residents’ physical and mental QOL. The assessment of residents’ depressive symptoms ought to be integrated into the annual system that evaluates care quality and determines the number of work staff at LTC facilities. The training in depressive assessment for nurses in LTC facilities is extremely important. A sensitive and reliable method for assessing depressive symptoms among institutionalized older residents is important. One such assessment tool is the minimum data set-based depression rating scale, which includes direct observations of the residents, communication with the care assistants, reviews of the clinical records, and consultations with family members and friends, rather than the direct responses of a resident to standardized screening questions (Martin et al., 2008). Multiple methods to assess depressive symptoms are recommended in order to increase the sensitivity and accuracy of the screening, especially for those with impaired cognition status. Source of Funding Funding for the research was provided by the Taipei Veterans General Hospital, Taiwan (V97D-002). Acknowledgment
Limitations The cross-sectional design of this study and the fact that we only collected data from LTC facilities in Taipei city limit our ability to generalize our findings. Another study limitation is that residents with impaired cognition status were excluded from this study because they were unable to provide valid and reliable data regarding depressive symptoms and QOL.
Conclusion Depressive symptoms mediate the effects of ADLs and the number of chronic diseases on the physical and mental aspects of QOL. Improving depressive symptoms appears to be necessary for improving both the physical and mental aspects of QOL of institutionalized people of advanced age. Perspectives in Psychiatric Care 50 (2014) 58–64 © 2013 Wiley Periodicals, Inc.
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among older adults admitted to complex continuing care: Implications for the depression rating scale (DRS). Age and Ageing, 37, 51–56. doi:10.1093/ageing/afm162 Ministry of the Interior. (2008). Statistics and analysis on long-term care facilities 2008. Ministry of the Interior, Taipei. Ministry of the Interior. (2013). Statistics and analysis on long-term care facilities 2011. Retrieved January 14, 2013, from http://statis.moi.gov.tw/micst/stmain.jsp?sys=220&ym= 10106&ymt=10106&kind=21&type=1&funid=c0420101& cycle=43&outmode=0&compmode=0&outkind=1&fldspc= 0,3,&cod00=1&cod10=1&rdm=iBdnpB6q Pfeiffer, E. (1975). A short portable mental status questionnaire for the assessment of organic brain deficit in elderly patients. Journal of the American Geriatrics Society, 23(10), 433–441. Salguero, A., Martínez-García, R., Molinero, O., & Márquez, S. (2011). Physical activity, quality of life and symptoms of depression in community-dwelling and institutionalized older adults. Archives of Gerontology and Geriatrics, 53(2), 152–157. doi:10.1016/j.archger.2010.10.005 Scuteri, A., Spazzafumo, L., Cipriani, L., Gianni, W., Corsonello, A., Cravello, L., . . . Sebastiani, M. (2011). Depression, hypertension, and comorbidity: Disentangling their specific effect on disability and cognitive impairment in older subjects. Archives of Gerontology and Geriatrics, 52(3), 253–257. doi:10.1016/j.archger.2010.04.002 Shah, S., Vanclay, F., & Cooper, B. (1989). Improving the sensitivity of the Barthel Index for stroke rehabilitation. Journal of Clinical Epidemiology, 42(8), 703–709. Shibata, A., Oka, K., Nakamura, Y., & Muraoka, I. (2007). Recommended level of physical activity and health-related quality of life among Japanese adults. Health and Quality of Life Outcomes, 5, 64–71. doi:10.1186/1477-7525-5-64 Smith, E. (1982). Beliefs, attributions, and evaluations: Nonhierarchical models of mediation in social cognition. Journal of Personality and Social Psychology, 43, 248–259. Sobel, M. E. (1982). Asymptotic confidence intervals for indirect effects in structural equation models. In S. Leinhart (Ed.), Sociological methodology (pp. 290–312). San Francisco: Jossey-Bass. Tseng, H. M., Lu, J. F. R., & Tsai, Y. J. (2003). Assessment of health-related quality of life in Taiwan (II): Norming and validation of SF-36 Taiwan version. Taiwan Journal of Public Health, 22(26), 512–518. Tseng, S. Z., & Wang, R. H. (2001). Quality of life and related factors among elderly nursing home residents in Southern Taiwan. Public Health Nursing, 18(5), 304–311. Ware, J. E. (2005). SF-36 health survey manual and interpretation guide. Boston: Medical Outcomes Trust. Watson, H. J., Allen, K., Fursland, A., Byrne, S. M., & Nathan, P. R. (2012). Does enhanced cognitive behaviour therapy for eating disorders improve quality of life? European Eating Disorders Review, 20(5), 393–399. doi:10.1002/erv.2186
Perspectives in Psychiatric Care 50 (2014) 58–64 © 2013 Wiley Periodicals, Inc.
Perspectives in Psychiatric Care
ISSN 0031-5990
The Effects of Depressive Symptoms on Quality of Life Among Institutionalized Older Adults in Taiwan I-chuan Li, PhD, Huai-Ting Kuo, MSN, Kuan-Chia Lin, PhD, and Yi-Chen Wu, MSN I-chuan Li, PhD, is a Professor, Institute of Clinical and Community Health Nursing, National Yang-Ming University, Taipei, Taiwan; Huai-Ting Kuo, MSN, is a Doctoral Student, Department and Institute of Nursing, National Yang-Ming University, Taipei, Taiwan; Kuan-Chia Lin, PhD, is a Professor, Department of Health Care Management, National Taipei University of Nursing and Health Sciences, Taipei, Taiwan; and Yi-Chen Wu, MSN, is a Nursing Clinical Preceptor, Department of Gerontological Care and Management, Chang Gung University of Science and Technology, Taoyuan, Taiwan.
Search terms: Depressive symptoms, mediating factors, quality of life Author contact: [email protected], with a copy to the Editor: [email protected] Conflict of Interest Statement There is no conflict of interests for all authors. First Received October 25, 2012; Final Revision received April 14, 2013; Accepted for publication April 23, 2013.
PURPOSE: To explore the effect of physical health status and depressive symptoms on quality of life (QOL) and to examine whether depressive symptoms mediate the effect of physical health status on the physical and mental components of QOL among institutionalized older adults. DESIGN AND METHODS: A cross-sectional study was used to assess 306 residents from 73 long-term care facilities in Taipei, Taiwan. FINDINGS: We found that depressive symptoms mediated the relationship between the number of chronic diseases and activities of daily living and physical components of QOL (z = −2.41, p = .016; z = 3.33, p < .001) as well as between the number of chronic diseases and mental components of QOL (z = −2.45, p = .014). PRACTICE IMPLICATIONS: Our findings indicate that alleviating depressive symptoms can improve the QOL of older adults in long-term care facilities.
doi: 10.1111/ppc.12029
Background The proportion of older people is increasing in Western countries and in Taiwan. The percentage of the elderly population, defined as the population of people aged 65 and over, increased from 7.0% in 1993 to 10.4% in 2008 (Ministry of the Interior [MOI], 2008). It is projected that by 2025, approximately 20% of Taiwan’s population will be 65 years of age or older (Council for Economic Planning and Development [CEPD], 2008). This has resulted in a steadily increasing demand for long-term care (LTC) services in Taiwan. By 2015, the percentage of older people in need of LTC will be about 10.83% (MOI, 2008). Approximately 20.0% of Taiwan’s older adult population who requires assistance with activities of daily living (ADLs) receives LTC services (CEPD, 2009).This finding may partially explain the increase in the number of registered LTC facilities from 70 in 1997 to 1,064 in 2011 (MOI, 2013). Quality of life (QOL) is defined as an individual’s overall satisfaction with life and general sense of well-being (Huang, Wu, & Frangakis, 2006). Patient-reported outcomes are often used to measure QOL, a term which is used interchangeably with health-related quality of life (HRQOL), health status, and subjective well-being. According to Andersen, WittrupJensen, Lolk, Andersen, and Kragh-Sørensen (2004), measures of HRQOL are important for evaluating disability and 58
predicting mortality of frail people of advanced age. Thus, the regular monitoring of QOL is important. Although measurement of QOL has become a major focus of significant importance in clinical studies, very little attention has been paid to QOL of older persons in LTC facilities (Chang et al., 2010). QOL is a multidimensional concept (Gilhooly, Gilhooly, & Bowling, 2005), and different factors may have an impact on both physical and mental components of QOL. Identifying factors that influence those components of QOL in the elderly is important to provide direction and to make policies for improving QOL in institutionalized older persons. Depression has a significant impact on QOL. Studies have shown that elderly persons with depression are at high risk of having poor QOL (Chang & Chueh, 2011; Lin, Yen, & Fetzer, 2008) regardless of whether they are living in an LTC facility or living alone. Studies conducted in Taiwan have shown that the likelihood of developing depressive symptoms increased in proportion to the number of chronic diseases in institutionalized elderly individuals (Chang & Chueh, 2011; Huang, Dong, Lu, Yue, & Liu, 2010). The number of chronic diseases can be a significant predictor of depression. Andersen et al. (2004) found that the inability to independently perform ADL was the major factor affecting QOL. According to Salguero, Martínez-García, Molinero, and Márquez (2011), decreased mobility in older people impacts Perspectives in Psychiatric Care 50 (2014) 58–64 © 2013 Wiley Periodicals, Inc.
The Effects of Depressive Symptoms on Quality of Life Among Institutionalized Older Adults in Taiwan
QOL. There was one domestic study found that daily activities, physical symptoms, chronic diseases, physical performance, educational levels, and the number of caregivers have significant impacts on QOL (Lai et al., 2005). There is growing evidence that physical activity improves HRQOL by enhancing psychological well-being (Shibata, Oka, Nakamura, & Muraoka, 2007). The amount of food intake has been shown to be a significant predictor of depressive symptoms and QOL.According to Watson, Allen, Fursland, Byrne, and Nathan (2012),treatment of eating disorders can improve patients’ depression symptoms. Individuals with eating disorders experience poorer QOL compared with healthy individuals and those with serious physical illnesses (Jenkins, Hoste, Meyer, & Blissett, 2011). QOL is clearly impaired in individuals with eating disorders (Jenkins et al., 2011). QOL is clearly impaired in individuals with eating disorders.Thus,variability in food intake is known to relate to depressive symptom and QOL. However, to the best of our knowledge, the interactions among physical health status, depressive symptoms, and different aspects of physical and mental components of QOL in older adults who reside in LTC institutions have not been tested. Whether depressive symptoms mediate the effect of physical health status on physical and mental components of QOL has yet to be explored.In the present study,we were interested in understanding the relationships among physical health status, including the number of chronic diseases and ADLs, depressive symptoms, and QOL; therefore, variables such as educational level and the number of caregivers were not included in the mediation testing of QOL. This study tested whether depressive symptoms mediate the effect of physical health status, including ADL and the number of chronic diseases, on the physical and mental components of QOL in institutionalized elderly individuals in Taiwan. According to Judd and Kenny (2010), the conclusions from a mediation analysis are valid only if the causal assumptions are valid. The amount of food intake has been shown to be a significant predictor of depressive symptoms and QOL (Jenkins et al., 2011; Watson et al., 2012). Thus, we treated variability in food intake as an instrumental variable (IV) by measuring the number of full meals eaten during the past 3 months. Methods Design and Research Subjects Inclusion criteria of sampling included a healthy cognition status, which was tested by the Short Portable Mental Status Questionnaire (SPMSQ), and the ability to verbally communicate. Residents with SPMSQ scores < 8, indicating cognitive impairment, were excluded. Thus, those who have intact cognitive function were research subjects in this study. We Perspectives in Psychiatric Care 50 (2014) 58–64 © 2013 Wiley Periodicals, Inc.
received a list of community-based LTC facilities from the Department of Social Welfare in Taipei. In Taipei, a total of 307 registered facilities had a total of 10,647 beds. After we explained the aims of this study to the administrators of the facilities, 73 facilities agreed to participate. These facilities represented approximately 24% of the LTC facilities in this area. A total of 3,577 residents were being cared for at the 73 facilities, and 321 of those met the inclusion criteria for this study, representing approximately 9% of all residents with intact cognitive function. The participation rate in this study was 95% among qualified older residents. Between 1 and 11 participants from each facility participated in this study, with an average of 4.3 participants at each facility. Thus, overrepresentation by any one institution was not an issue. Study Instruments SPMSQ was used to assess residents’ cognitive functions (Pfeiffer, 1975). The assessment includes 10 questions divided among four domains: orientation (3 items), personal history (3 items), remote memory (3 items), and calculation (1 item). Scores ranging from 0 to 2 indicate severe cognitive impairment, those ranging from 3 to 5 indicate moderate cognitive impairment, scores ranging from 6 to 7 indicate mild cognitive impairment, and scores ranging from 8 to 10 indicate intact cognitive function. ADL scores were determined using the modified Barthel Index, which consists of 10 items: feeding, bathing, dressing, personal hygiene, toilet ability, bowel control, bladder control, transfer (from bed to chair and back), walking, and going up and down stairs. Total scores range from 0 to 100, with higher scores indicating greater independence: 0–20 indicates total dependence, 21–60 indicates severe dependence, 61–90 indicates moderate dependence, 91–99 indicates slight dependency, and 100 indicates functional independence. Depressive symptoms were evaluated using the short form of the Geriatric Depression Scale (GDS-SF). Subjects replied to a series of questions with either a “yes” (1) or a “no” (0) answer to describe their feelings during the previous 2 weeks. The GDS-SF includes 15 items with scores ranging from 0 to 15; a score ranging from 0 to 4 indicates no depressive symptoms; scores ranging from 5 to 9 represent possible clinical depressive symptoms; and scores ranging from 10 to 15 indicate severe depressive symptoms (Lee et al., 1993). HRQOL is based on subjective attitudes and experiences of physical, social, and mental health (Borgaonkar & Irvine, 2000). In this study, we measured QOL with the Taiwan version of the short form, which comprises 36 items (SF-36). The SF-36 includes 36 questions that cover eight domains: physical functioning, role limitation due to physical function, bodily pain, general health, vitality, social functioning, role limitation due to emotional problems, and mental health. The eight domains were grouped into a physical component 59
The Effects of Depressive Symptoms on Quality of Life Among Institutionalized Older Adults in Taiwan
summary and a mental component summary, which represent subjective physical health and mental health, respectively. The response scores for each dimension were summed, and the total was standardized and converted to a score ranging from 0 to 100. A higher score indicated higher levels of perceived QOL (Ware, 2005). Data Collection Data on ADL, GDS-SF, and SF-36 were collected from August 2008 to May 2009 by one well-trained investigator. The investigator, a graduate nursing student who is a highly experienced LTC nurse with 4 years of work experience at a teaching hospital, conducted all of the resident interviews. This investigator was trained by the study’s principal investigator, and the inter-rater reliability was above 0.90 for the SPMSQ, ADL, GDS-SF scores, and SF-36 scores. The investigator used the SPMSQ to screen all of the target residents to select those with intact cognitive function in order to assess the participants’ depressive symptoms and QOL. The facility nurses provided the investigator with information regarding daily routines related to the estimation of the amount of food eaten. Socio-demographic characteristics, ADL status, and medical diagnoses were retrieved by the investigator from the existing records of the 306 participating residents. Ethical Consideration This study was approved by the Institutional Review Board of the Yang-Ming University in Taipei. All participants in the study participated voluntarily and provided informed consent. Potential subjects were free to decline during the process of this study without any repercussion. Human rights and privacy of participants were protected. Confidentiality during the entire study was maintained using numerical identifiers on recorded data. Data Analysis A multiple hierarchical regression analysis was used to understand which of the demographic characteristics, variables of physical health status, and depressive symptoms are predictive of the physical and mental components of QOL. The variables that were statistically significant after performing the association analyses were entered into the regression analysis. The Sobel’s significance test was used to test whether physical health status and depressive symptoms have an impact on QOL (Sobel, 1982). This test is best explained with the aid of a simple model. The first step tested the association between the independent variable (physical health status) and the outcome/dependent variable (QOL). The second step tested the association between the independent variable (physical health status) and the mediator (depressive symptoms). The 60
third step tested the model with both the independent variable and the mediator predicting the outcome variable, demonstrating that the mediator was associated with the outcome variable in this multiple regression model. The path between the independent variable and the outcome/dependent variable was also tested to determine whether this was reduced to zero (total mediation) or reduced by a significant amount (partial mediation) (Dudley, Benuzillo, & Carrico, 2004). For all tests, results with p values less than .05 (two tailed) were considered statistically significant. In order to avoid violating the multicollinearity assumptions between depressive symptoms and QOL, there must be an IV that is known to relate to depressive symptom and QOL (Smith, 1982). Both the mediator and the outcome variables are treated as outcome variables, and they each may mediate the effect of the other. IV regression in the form of two-stage least squares (2SLS) was used to address the participants’ endogenous choices of some of our variables, such as depressive symptoms. In this study, we treated variability in food intake as an IV by measuring the number of full meals eaten during the past 3 months. Validity and Reliability The Chinese version of the ADL scale was developed by Shah, Vanclay, and Cooper (1989) from the original Barthel Index by modifying the scoring method to increase test sensitivity. The Chinese version of the GDS-SF has an internal consistency reliability of 0.89, a test–retest reliability of 0.85, a criterion-related validity of 0.95, and a concurrent validity of 0.96 (Chan, 1996). The SF-36 has been shown to have good reliability and validity in a general population in Taiwan (Lu, Tseng, & Tsai, 2003; Tseng, Lu, & Tsai, 2003). Cronbach’s alpha coefficients for the eight subscales of the SF-36 Taiwan version have been reported as 0.91, 0.92, 0.76, 0.82, 0.79, 0.65, 0.87, and 0.78, respectively (Lu et al., 2003). In this study, the Cronbach’s alpha was greater than 0.70 for all subscales (range 0.70–0.98). Results Characteristics of the Study Subjects In total, 306 subjects completed this study. As shown in Table 1, the age range was 65.08–96.58 years (mean age = 80.62, SD = 7.14) and the mean number of chronic diseases was 2.56 (SD = 1.21). The mean functional status score was 61.29 (SD = 31.92). Approximately 33% of the subjects had Barthel Index scores ranging from 61 to 90, indicating that they were moderately functionally dependent. Assessment of Depressive Symptoms and QOL The mean GDS-SF score was 5.85 (SD = 4.23). In addition, half of the participants (n = 166, 54.25%) had GDS-SF scores Perspectives in Psychiatric Care 50 (2014) 58–64 © 2013 Wiley Periodicals, Inc.
The Effects of Depressive Symptoms on Quality of Life Among Institutionalized Older Adults in Taiwan
Table 1. Characteristics of Participating Subjects (n = 306)
Variables
Mean (SD)
Gender Male Female Age (years) 65–74 75–84 ≥ 85 Educational levels (years) None 1–6 ≥7 Marital status With spouse Without spouse Financial support Family Nonfamily Number of chronic disease 0–2 ≥3 Whether taking medicines No Yes ADLs Total dependency Severe dependency Moderate dependency Slight dependency Independency GDS-SF score Normal (0–4) Depressive symptoms (5–9) Depression (10–15) QOL PCS MCS
Range
n (%) 160 (52.29) 146 (47.71)
80.62 (7.14)
65.08–96.58 71 (23.20) 146 (47.71) 89 (29.08) 80 (26.14) 118 (38.56) 108 (35.29) 85 (27.78) 221 (72.22) 215 (70.26) 91 (29.74)
2.56 (1.21)
0–7 153 (50.00) 153 (50.00) 10 (3.27) 296 (96.73)
61.29 (31.92)
0–100 58 83 100 32 33
5.85 (4.23)
(18.95) (27.12) (32.68) (10.46) (10.78)
0–15 135 (44.12) 90 (29.41) 76 (24.84)
37.20 (11.27) 51.39 (12.75)
6.93–64.93 16.85–75.97
Notes: SD, standard deviation; ADLs, activities of daily living; GDS-SF, Geriatric Depression Scaleshort form; QOL, quality of life; PCS, physical component summary; MCS, mental component summary.
of 5 or greater, indicating that they require further evaluation by a psychiatric specialist. Among the different QOL domains, bodily pain yielded the highest score (M = 79.15, SD = 27.74), while physical functioning (M = 28.96, SD = 29.27) yielded the lowest score. The Relationship Among Physical Health Status, Depressive Symptoms, and QOL We found that participants with fewer chronic diseases, higher ADL scores, and lower GDS-SF scores had significantly higher scores of the physical components of the QOL score (r = −.14, p = .014; r = .50, p < .001; and r = −.35, p < .001, respectively) (Table 2). The number of chronic diseases (r = −.18, p < .002) and GDS-SF scores (r = −.69, p < .001) is significantly Perspectives in Psychiatric Care 50 (2014) 58–64 © 2013 Wiley Periodicals, Inc.
correlated with mental components of the QOL score (Table 2). Multiple hierarchical regression analysis was used to understand which of the demographic characteristics, variables of physical health status, and depressive symptoms preTable 2. Correlation Between Demographics, Depressive Symptoms, and QOL (n = 306) Variable
PCS
MCS
Age Number of chronic disease ADL score GDS-SF score
0.07 −0.14* 0.50*** −0.35***
−0.04 −0.18** 0.06 −0.69***
Notes: *p < .05, **p < .01, ***p < .001. ADL, activity of daily living; QOL, quality of life; GDS-SF, Geriatric Depression Scale-short form; PCS, physical component summary; MCS, mental component summary.
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The Effects of Depressive Symptoms on Quality of Life Among Institutionalized Older Adults in Taiwan
Table 3. Hierarchical Multiple Regression Explaining the Relationships of Health Status and GDS With QOL PCS
MCS
OLS
2SLS
OLS
2SLS
Variable
Coefficients (SE)
Coefficients (SE)
Coefficients (SE)
Coefficients (SE)
ADL score Number of chronic disease GDS-SF score Gender: Male
0.176*** (0.018) −1.302* (0.529) −1.066*** (0.164) 2.030 (1.293)
0.177*** (0.018) −1.304* (0.529) −1.078*** (0.165) 2.036 (1.295)
0.023 (0.023) −1.898** (0.594) −2.351*** (0.143) 3.827** (1.452)
0.020 (0.023) −1.911** (0.593) −2.356*** (0.144) 3.877** (1.450)
Notes: *p < .05, **p < .01, ***p < .001. OLS, ordinary least squares; 2SLS, two-stage least squares; PCS, physical component summary; MCS, mental component summary; GDS, Geriatric Depression Scale; QOL, quality of life; ADL, activity of daily living; GDS-SF, Geriatric Depression Scale-short form; SE, standard error.
dicted the physical component of QOL and the mental component of QOL. 2SLS regression analysis has been applied to replace the standard ordinary least squares analysis (Table 3). In the first stage of this IV-2SLS estimation, we obtained the predicted probability of depressive symptoms for each individual in the sample using IVs. The predicted probability of depressive symptoms was then used as a regressor in the main model of QOL, replacing the endogenous variable of depressive symptoms that is potentially correlated with the error term in the regression equation. Results of 2SLS showed that the IV significantly predicted depressive symptoms (p = .003) and the physical and mental components of QOL (p = .001 and p < .001, respectively), implying that the mediation test can be considered (Table 3). The variables that were statistically significant after performing the association analyses were entered into the regression analysis. The variables of ADLs and GDS-SF scores were significant predictors of the physical component of QOL (R2
= .37, F = 50.46, p < .001). In addition, the number of chronic disease and GDS-SF scores was a significant predictor of the mental component of QOL (R2 = .49, F = 91.60, p < .001). The results of the Sobel test showed that depressive symptoms mediated the effects of ADLs on the physical components of QOL (standardized β = 0.16, Sobel test z = 3.33, p < .001) to a degree of 11.11%. Depressive symptoms significantly mediated 40% and 53.68% of the effect of the number of chronic diseases on the physical and mental components of QOL, respectively (z = −2.41, p = .016 and z = −2.45, p = .014, respectively) (Table 4). Discussion The QOL scores in this study were much lower than those reported in a similar study conducted in Taiwanese nursing homes (Tseng & Wang, 2001). In addition, scores for three of the eight domains of the SF-36 (physical functioning,
Table 4. Regression Models and Sobel’s Test
Model Model 1: Depressive symptoms mediate the ADLs → PCS link ADLs → PCS Depressive symptoms → PCS ADLs → depressive symptoms ADLs → PCS | depressive symptoms Model 2: Depressive symptoms mediate the number of chronic disease → PCS link Number of chronic disease → PCS Depressive symptoms → PCS Number of chronic disease → depressive symptoms Number of chronic disease → PCS | depressive symptoms Model 3: Depressive symptoms mediate the number of chronic disease → MCS link Number of chronic disease → MCS Depressive symptoms → MCS Number of chronic disease → depressive symptoms Number of chronic disease → MCS | depressive symptoms
Regression test
Sobel’s test with Bootstrap methoda
B
SE
p
Indirect value
0.18 −1.07 −0.03 0.16
0.02 0.16 0.01 0.02
< .001 < .001 < .001 < .001
0.02
0.01 ∼ 0.03
11.11
−1.30 −1.07 0.44 0.33
0.53 0.16 0.18 0.17
.014 < .00 .012 .047
−0.52
−0.97 ∼ −0.09
40.00
−1.90 −2.35 0.44 −0.85
0.59 0.14 0.18 0.44
.002 < .00 .012 .053
−1.02
−1.86 ∼ −0.19
53.68
95% CI
Mediation (%)
Notes: ADLs, activities of daily living; PCS, physical component summary; MCS, mental component summary; SE, standard error; CI, confidence interval. a Using Bootstrap method to derive a confidence interval for indirect value.
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The Effects of Depressive Symptoms on Quality of Life Among Institutionalized Older Adults in Taiwan
social functioning, and mental health) were significantly lower in the study sample than in the general population of older Taiwanese individuals (Lu et al., 2003). The participants in the present study had an average of 2.56 chronic diseases, which was shown to be a significant predictor of the mental component of QOL. Institutionalized elderly with two or more chronic diseases have been shown to be at higher risk of having a poor mental component of QOL (Lai et al., 2005). The existence of chronic diseases correlated with one’s vitality, poorer social functioning, and role limitation, and caused emotional and mental health problems (Scuteri et al., 2011). In this study, ADL status was a significant predictor of the physical component of QOL. This finding is consistent with that reported by Tseng and Wang (2001). ADL is a global measurement that describes functional status in the elderly and reflects certain levels of dependence, disease severity, and resource consumption (Andersen et al., 2004). Residents with poorer ADLs should be monitored closely for the physical component of QOL. We know of no other studies that evaluated the physical health status-depressive symptoms-QOL mediation chain by testing the differential effects on the physical and mental components of QOL independently. Our study has shown that depressive symptoms are an important mediator between health status and impaired QOL among institutionalized elders. Although the number of chronic diseases cannot be changed, we can alleviate depressive symptoms and subsequently improve QOL. Thus, it is necessary to develop strategies to alleviate depressive symptoms in order to improve the mental component of QOL of institutionalized people of advanced age. The assessment of depressive symptoms in institutionalized older adults is important for early intervention and prevention, which may contribute to improvements in physical and mental components of QOL.
Implications for Nursing Practice Depressive symptoms determined by the GDS-SF had a negative relationship with the physical and mental components of QOL among older institutionalized Taiwanese. Therefore, healthcare professionals can improve the physical and mental components of QOL of residents of LTC facilities by treating depressive symptoms. It is necessary to conduct intervention trials to see whether they would improve depressive symptoms and to examine the effect of a reduction in depressive symptoms on QOL in a future study. It is important to monitor depressive symptoms regularly in order to improve residents’ physical and mental QOL. The assessment of residents’ depressive symptoms ought to be integrated into the annual system that evaluates care quality and determines the number of work staff at LTC facilities. The training in depressive assessment for nurses in LTC facilities is extremely important. A sensitive and reliable method for assessing depressive symptoms among institutionalized older residents is important. One such assessment tool is the minimum data set-based depression rating scale, which includes direct observations of the residents, communication with the care assistants, reviews of the clinical records, and consultations with family members and friends, rather than the direct responses of a resident to standardized screening questions (Martin et al., 2008). Multiple methods to assess depressive symptoms are recommended in order to increase the sensitivity and accuracy of the screening, especially for those with impaired cognition status. Source of Funding Funding for the research was provided by the Taipei Veterans General Hospital, Taiwan (V97D-002). Acknowledgment
Limitations The cross-sectional design of this study and the fact that we only collected data from LTC facilities in Taipei city limit our ability to generalize our findings. Another study limitation is that residents with impaired cognition status were excluded from this study because they were unable to provide valid and reliable data regarding depressive symptoms and QOL.
Conclusion Depressive symptoms mediate the effects of ADLs and the number of chronic diseases on the physical and mental aspects of QOL. Improving depressive symptoms appears to be necessary for improving both the physical and mental aspects of QOL of institutionalized people of advanced age. Perspectives in Psychiatric Care 50 (2014) 58–64 © 2013 Wiley Periodicals, Inc.
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