Women & Health, 55:152–166, 2015 Copyright © Taylor & Francis Group, LLC ISSN: 0363-0242 print/1541-0331 online DOI: 10.1080/03630242.2014.979966

Factors Associated with Health-Related Quality of Life Among Overweight and Obese Korean Women JINA CHOO, PhD, DrPH, RN Department of Community Health Nursing, College of Nursing, Korea University, Seoul, South Korea

MELANIE T. TURK, PhD, RN School of Nursing, Duquesne University, Pittsburgh, Pennsylvania, USA

SAE YOUNG JAE, PhD Department of Sport Science, University of Seoul, Seoul, South Korea

IL HAN CHOO, MD, PhD Department of Neuropsychiatry, School of Medicine, Chosun University, Gwangju, South Korea

Health-related quality of life (HRQOL) tends to be lower among individuals who are overweight and obese than those of normal weight, and women may be more vulnerable to lower HRQOL associated with obesity than men. Identifying factors associated with HRQOL may be crucial for improving HRQOL for overweight/obese women. We aimed to determine the factors associated with obesity-specific HRQOL among overweight/obese Korean women. A cross-sectional study was conducted with 125 women aged 20–64 years, who comprised a baseline sample in the Community-based Heart and Weight Management Trial. The data were collected from September 2010 to November 2011. The Weight Efficacy Lifestyle, Beck Depression Inventory-II, Interpersonal Social Evaluation List, and Impact of Weight on Quality of Life (IWQOL)–Lite scales were used to measure self-efficacy for weight control, depressive symptoms, social support, and HRQOL, respectively. Increased body mass index, lower self-efficacy Received July 11, 2013; revised March 26, 2014; accepted March 30, 2014. Address correspondence to Jina Choo, PhD, DrPH, RN, Department of Community Health Nursing, College of Nursing, Korea University, Anam-Dong, Seongbuk-Gu, Seoul 136-705, South Korea. E-mail: [email protected]

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for weight control, and higher levels of depressive symptoms were significantly associated with greater impairment in total IWQOL in the regression models. However, social support was not significantly associated with IWQOL. Along with weight loss strategies, other strategies for improving self-efficacy and alleviating depressive symptoms may be essential for improving HRQOL among overweight and obese women. KEYWORDS obesity, women, self-efficacy, depression, social support, quality of life

INTRODUCTION Health-related quality of life (HRQOL) has been found to be lower among individuals who are overweight and obese than those of normal weight (Jia and Lubetkin 2005; Søltoft, Hammer, and Kragh 2009). Overweight and obese women may be particularly more vulnerable to lower HRQOL than their male counterparts. Overweight and obesity per se may have a stronger association with perceived physical impairments in HRQOL among women than among men (Andrés et al. 2012). Such a gender difference in impaired HRQOL may be also attributable to psychological and social backgrounds among obese women. For example, from a psychosocial perspective, obese women are more likely to experience weight-related stigma, discrimination, body image disturbances, and depression than obese men (Cox et al. 2011; Hammoud et al. 2011). Moreover, women are more likely to view their own overweight or obese body negatively and ascribe a negative social meaning to it than men (Bergenstal et al. 2011; Davies and Speight 2012; Mohamed et al. 2010). Therefore, identifying factors associated with obesity-specific HRQOL may be crucial for improving HRQOL in overweight and obese individuals, especially in women. However, little evidence exists regarding psychosocial factors that may be related to HRQOL in overweight and obese women. Self-efficacy, a primary construct of social cognitive theory by Albert Bandura, involves people’s beliefs in their capabilities to perform a specific action required to attain a desired outcome and to successfully cope with challenging conditions to achieve that outcome (Bandura 1997). Self-efficacy is increasingly recognized as an essential component of well-being and quality of life. Studies have found that self-efficacy is a strong psychological factor associated with HRQOL in patients with certain diseases (Kohler, Fish, and Greene 2002; Korpershoek, van der Bijl, and Hafsteinsdóttir 2011, Kreitler, Peleg, and Ehrenfeld 2007; Middleton, Tran, and Craig 2007); these studies have indicated that self-efficacy for control of their medical condition was a strong predictor of HRQOL, regardless of concurrent limited physical

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functioning. Thus far, no known previous studies have reported an association between self-efficacy for weight control and HRQOL in overweight and obese individuals. Depressive symptoms are also a psychological factor that may be associated with HRQOL in overweight and obese individuals. However, few studies have examined the relationship between depressive symptoms and HRQOL among obese individuals (Vetter et al. 2011), and no evidence exists regarding the association of depressive symptoms with HRQOL, as assessed by an obesity-specific HRQOL measure. Social support is the functional component of relationships that can be categorized in broad types of supportive behaviors or acts: tangible, emotional, informational, and appraisal support (House 1981). A lack of social support in family and peer relationships has been reported among obese individuals (Carr and Friedman 2006). Yet perceived social support has rarely been examined in relationship to quality of life among overweight and obese individuals. Thus, exploring a possible relationship between social support and HRQOL in overweight and obese women is warranted. Various validated tools have been applied to the measurement of HRQOL; these tools are divided into generic and disease-specific measures. Compared to generic measures, disease-specific tools assess the specific states and issues associated with certain diagnoses and have the sensitivity and specificity to best detect the impact of a specific condition (i.e., obesity) on daily functioning (Herzer et al. 2011; Vasiljevic et al. 2012). In this context, an obesity-specific HRQOL measure, the Impact of Weight on Quality of Life (IWQOL)—Lite, was used in the present study to assess the effects of obesity on quality of life (Kolotkin et al. 2001). We aimed to explore potential factors associated with obesity-specific HRQOL among overweight and obese Korean women who sought weight management treatment. We explored if increased body mass index (BMI) was significantly associated with obesity-specific HRQOL. Next, we determined if psychosocial factors—self-efficacy for weight control, depressive symptoms, and interpersonal social support—were significantly associated with obesityspecific HRQOL.

METHODS Study Design Across-sectional, correlational study design was carried out on the baseline sample from a parent study, the Community-based Heart and Weight Management Trial (ISRCTN46069848) (Choo, Lee, Cho, Burke, Sekikawa, and Jae 2014). The parent study was a single-center, randomized controlled trial designed to examine the effects of weight management by three different modes of exercise interventions (aerobic, resistance, or combination exercise) on weight loss, psychological and cardio-metabolic risk factors,

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and vascular function among women with abdominal obesity. The eligibility criteria for the parent study were: (1) ages between 18 and 65 years; (2) waist circumference of 85 cm or greater, the criteria for abdominal obesity as defined by the Korean Society for the Study of Obesity (Lee et al. 2007); (3) willingness to be randomly assigned to one of three different exercise modes; (4) no current medical conditions, such as cardiovascular diseases, diabetes, or cancers requiring physician supervision; and (5) no physical limitation restricting exercise ability.

Sample and Setting Between September 2010 and November 2011, the participants were recruited into two cohorts spaced 7 months apart, from a community in Seoul, South Korea. Various methods of recruitment included the use of posters and leaflets; the database of a community health center; and telephone and mailing announcement to staff, students, and faculty at Korea University. Specifically, we used the database of the Seoul Metabolic Syndrome Management Project (Lee et al. 2013) from a community health center in Seoul. The rate of those from the database meeting the eligibility criteria was 11.2% (163 out of 1,455) in the parent study. We called all of these eligible participants to assess their willingness to participate in the parent study. Those who indicated their willingness were invited to an orientation, where the participants (N = 145) were provided a detailed study overview. They were screened again for the eligibility criteria; 126 participants satisfied the eligibility criteria and completed self-administered questionnaires. Finally, of 126 participants, we excluded one who fell below the BMI cut-off point of 23.0 kg/m2 , for a final sample size of 125 for the present analyses. In Korea, overweight and obesity are determined according to the BMI criteria of 23.0–24.9 and of 25 or higher, respectively (Kim, Suh, and Choi 2004). The participation rate was 78.9% (125 out of 163). The present study was approved by the Institutional Review Board at Korea University (KU-IRB-11-10-A-2). All participants provided written, signed, informed consent, and all procedures were followed in accordance with the ethical standards of this board.

Measures BMI was computed as body weight (kg) divided by height (cm) squared. Using the Tanita bioelectrical impedance scale (Tanita Corporation of America, Inc., IL, USA), body weight was measured after an overnight fast with the participant in light clothing and without shoes. Height was measured to the nearest centimeter on a wall-mounted stadiometer. The Weight Efficacy Lifestyle (WEL) questionnaire was used to measure self-efficacy for weight control, one’s confidence in the ability to resist eating

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in different situations (Clark et al. 1991). The scale is a 20-item measure, and item responses are ranked from 0 to 9, with higher scores indicating higher confidence. Total WEL scores range between 0–180 and between 0–36 for each subscale score. The five subscales consist of negative emotions (four items), availability (four items), social pressure (four items), and positive activities (four items). Psychometric properties have been well-established in samples of over 70% of women in their early 40s with Cronbach’s alpha coefficients ranging from 0.70 to 0.90 (Clark et al. 1991). The English version of the WEL scale was translated into Korean separately by three Korean nursing scholars, and the three Korean versions were discussed, confirmed, and consolidated into a single Korean version. Then the Korean version was back-translated by a native English speaker. The back-translated English version was again confirmed by the nursing scholars who translated it into Korean. Cronbach’s alpha was 0.94 in the sample of the present study. The Korea version of Beck Depression Inventory (BDI)–II was used to assess severity of self-reported depressive symptoms (House 1981; Sung et al. 2008). The scale is a 21-item measure in which the item responses are ranked from 0 to 3, with higher scores indicating more severe depressive symptoms. The total score of BDI–II ranges from 0–63 and is categorized by: 0–13 for minimal, 14–19 for mild, 20–28 for moderate, and 29–63 for severe depressive symptoms. The BDI–II has high internal consistency (Cronbach’s alpha = 0.91), and an average test-retest reliability of 0.72 across 20 studies (Herzer et al. 2011). In this study, the Cronbach’s alpha was 0.88. The Interpersonal Support Estimation List (ISEL) was used to measure the perceived availability of social support resources. This scale consists of four 10-item subscales reflecting appraisal (availability of people one can talk to about personal problems), belonging (availability of someone with whom one can do things), tangible (instrumental aid), and self-esteem (perception of a positive comparison when comparing oneself with others) (Cohen et al. 1985). Responses range from definitely false to definitely true (from 0 to 3) on a 4-point Likert scale. Higher scores indicated a better perception of social support availability, ranging from 0 to 120 points for the total score and 0 to 30 points for each subscale score. Cronbach’s alpha coefficients for the total ISEL scores ranged from 0.88 to 0.90 in previous studies (Cohen et al. 1985). The English version of the ISEL scale was translated and back-translated in the same way as the WEL scale. In the present study, the Cronbach’s alpha was 0.94. The Impact of Weight on Quality of Life (IWQOL)–Lite is an obesityspecific HRQOL tool used to assess the effects of obesity on the quality of life (Kolotkin et al. 2001). The Korean version of IWQOL–Lite was used in the present study. The IWQOL–Lite is a self-report questionnaire consisting of 31 items that tap into an individuals’ weight-related concerns across five subscales: physical function (11 items), self-esteem (7 items), sexual life (4 items), public distress (5 items), and work (4 items). The items are

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answered on a 5-point scale from 1 (“never true”) to 5 (“always true”). According to the IWQOL–Lite scoring procedure, raw scores were converted to 0 (worst) to 100 (best) for the total score and each subscale. Psychometric properties have been well established in samples of 996 obese patients and controls, with Cronbach’s alpha coefficients of 0.96 for the total score and 0.90–0.94 for the subscales (Kolotkin et al. 2001). For the test-retest reliability, the coefficients were 0.94 for the total score and 0.81–0.88 for subscales in a community sample (Kolotkin and Crosby 2002). In the present study, Cronbach’s alpha was 0.94 for the total score and 0.83–0.92 for subscales.

Data Analysis Data were analyzed using STATA10.0 (StataCorp LP, USA). A p value of less than .05 was considered to be significant. To identify participants’ sociodemographic, health-related, and psychosocial characteristics; frequencies; percentages; means; and standard deviations were included as descriptive statistics. To examine correlations of study variables (i.e., BMI, WEL, BDI–II, ISEL, and IWQOL), Pearson’ correlations were performed. Next, to identify factors associated with HRQOL, a multiple regression analysis was performed with all study variables (i.e., BMI, WEL, BDI–II, and IWQOL) included as independent variables and each of IWQOL total and subscales included as outcome variables, after adjusting for covariates (i.e., age and marital status). The covariates were included in the multiple regression models when the variable showed a p value < .1 based on the results of crude associations with the total IWQOL–Lite score. No collinearity was observed among independent variables in the regression model. To assess model fit, an F-test was performed with adjusted R 2 values for each regression model. Based on the F-test, all of the models were significant (p < .05), indicating good fit to the data. Adjusted R 2 values ranged from 0.07–0.23.

RESULTS Participants’ Characteristics The participants were all Korean females with a mean age of 42.8 years (Table 1); 80.0% were married, 60.0% had a college education or higher, and 40.0% had a monthly household income of 4,000,000 Korean won (approximately $4,000) or greater. The participants had a mean BMI of 28.5 kg/m2 (23.2–42.7 kg/m2 of range; 76% in the category of overweight). Among the participants, 26.4% had obesity-related comorbid conditions, such as hypertension or dyslipidemia; 27.2% were postmenopausal; 6.4% and 9.6% were current smokers and alcohol drinkers (two or more times per week), respectively.

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TABLE 1 Participants’ Characteristics: Sociodemographic and Health-Related Variables (N = 125) Sociodemographic variables Age (years) Marital status Married Separated/widowed/divorced Single Education College educated or higher High school diploma or less Monthly household income (won)a ≤ 4,000,000 > 4,000,000 Employment (yes) Health-related variables Body weight (kg) BMI (kg/m2 ) Overweight (BMI < 30 kg/m2 ) Obese (BMI ≥ 30 kg/m2 ) Obesity-related co-morbid conditions (yes) Post-menopause (yes) Current smoking (yes) Alcohol drinking (≥ 2 times/week)

N (%)

Mean (SD) 42.8 (9.4)

100 (80.0) 5 (4.0) 20 (16.0) 75 (60.0) 50 (40.0) 56 (44.8) 69 (55.2) 50 (40.0) 72.3 (10.3) 28.5 (3.8) 95 30 33 34 8 12

(76) (24) (26.4) (27.2) (6.4) (9.6)

a

Participants were asked to report their income in millions of won, which is the South Korean currency; a million won is approximately equal to 889 U.S. dollars (The World’s Favorite Currency Site 2012). Abbreviations: BMI, body mass index; SD, standard deviation.

HRQOL and Psychosocial Independent Variables The self-esteem subscale of the IWQOL–Lite showed the lowest score (48.2 out of a possible 100), and the public distress subscale had the highest score (80.0 out of a possible 100) with regard to different aspects of quality of life (Figure 1). The mean total WEL score was approximately 106 out of a possible 180 points, and among the five subscales of the WEL, the availability subscale showed the lowest score (16.5 out of a possible 36), and the positive activities subscale had the highest score (25.4 out of a possible 36) (Table 2). The mean of BDI–II scores fell into the category of mild depressive symptoms. Approximately 29.6% of the participants were categorized as having moderate or severe depressive symptoms. The mean of the total ISEL scores revealed a moderate level of social support, and the mean scores of the four subscales of the ISEL (appraisal, tangible, self-esteem, and belonging) were similar (ranging from 19.0 to 22.2 out of a possible 30).

Correlations Between Study Variables Increased BMI was significantly correlated with lower total scores of the IWQOL (r = −0.23, p = .011), but was not correlated with WEL, BDI, and

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FIGURE 1 Health-related quality of life among overweight and obese women: IWQOL–Lite and its subscales. Abbreviations: IWQOL–Lite = Impact of weight on quality of life, brief version.

TABLE 2 Participants’ Characteristics: Psychosocial Variables (N = 125) Characteristic Self-efficacy: WEL scores Total Negative emotion Availability Social pressure Physical discomfort Positive activities Depressive symptoms: BDI–II scores Total Minimal (0–13) Mild (14–19) Moderate (20–28) Severe (29–63) Social support: ISEL scores Total Appraisal Tangible Self-esteem Belonging

n (%)

Mean (SD)

Range

Possible range

105.9 20.6 16.5 19.1 24.3 25.4

6–178 0–36 0–36 0–36 0–36 4–36

0–180 0–36 0–36 0–36 0–36 0–36

(37.1) (10.0) (8.7) (9.1) (7.9) (8.0)

13.7 (9.1)

0–63

68 (54.0) 20 (16.0) 28 (22.4) 9 (7.2) 82.5 22.2 20.5 19.0 20.6

(15.4) (4.5) (4.6) (3.7) (4.6)

30–114 8–30 7–30 4–27 6–30

0–120 0–30 0–30 0–30 0–30

Abbreviations: BDI-II, Beck Depression Inventory-II; ISEL, Interpersonal Support Evaluation List; SD, standard deviation; WEL, Weight Efficacy Life-Style.

ISEL scores (Table 3). Increased levels of self-efficacy and social support were significantly correlated with higher scores of total IWQOL (r = 0.34, p < .001; r = 0.19, p = .038, respectively), while increased levels of depressive symptoms were significantly correlated with lower total IWQOL scores

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TABLE 3 Pearson Correlations Between Study Variables (N = 125) r

BMI BMI Self-efficacy (WEL total) Depressive symptoms (BDI–II) Social support (ISEL total) IWQOL total

Self-efficacy (WEL total)

Depressive symptom (BDI–II total)

Social support (ISEL total)

1.00 0.06

1.00

−0.04

−0.08

0.13

0.07

−0.49∗∗∗

1.00

0.34∗∗∗

−0.30∗∗

0.19∗

−0.23∗

IWQOL total

1.00

1.00

Abbreviations: BDI-II, Beck Depression Inventory–II; BMI, Body Mass Index; ISEL, Interpersonal Support Evaluation List; IWQOL, Impact of Weight on Quality of Life; SD, standard deviation; WEL, Weight Efficacy Lifestyle. ∗ p < .05, ∗∗ p < .01, ∗∗∗ p < .001.

(r = −0.30, p = .001). Reduced levels of social support significantly correlated with increased levels of depressive symptoms (r = −0.49, p < .001).

Associations Between BMI and Psychosocial Factors with Aspects of HRQOL In multiple regression analyses controlling for age and marital status, BMI was significantly negatively associated with the total IWQOL (beta = −0.24, p = .004) and the subscale scores for physical function, public distress, and work (Table 4). The total WEL score was significantly positively associated with the total IWQOL score (beta = 0.32, p = < .001) and all the subscale scores. BDI–II scores were significantly and negatively associated with the total IWQOL score (beta = −0.23, p = .013) and the subscale scores for work. The total ISEL scores were not significantly associated with the total IWQOL score or any subscale scores.

DISCUSSION This study examined factors associated with obesity-specific HRQOL among overweight and obese women seeking weight management treatment. As expected, increased BMI was significantly associated with impairments in obesity-specific HRQOL; higher levels of depressive symptoms were also significantly associated with lower levels of obesity-specific HRQOL. Higher levels of self-efficacy for weight control were significantly associated with

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TABLE 4 Factors Associated With HRQOL—Total and Subscale IWQOL Scores (N = 125) Regression model beta valuesa

BMI Self-efficacy (WEL total) Depressive symptoms (BDI–II) Social support (ISEL total) Fb Adjusted R 2

Total

Physical function

Selfesteem

Sexual life

Public distress

Work

−0.24∗∗ 0.32∗∗ −0.23∗

−0.19∗ 0.19∗ −0.17

−0.12 0.29∗∗ −0.18

−0.07 0.27∗ −0.15

−0.43∗∗ 0.19∗ −0.13

−0.24∗∗ 0.35∗∗ −0.25∗

0.08

0.13

0.02

0.01

0.09

0.07

7.23∗∗ 0.23

3.61∗∗ 0.11

5.29∗∗ 0.17

2.42∗ 0.07

8.19∗∗ 0.25

6.82∗∗ 0.22

a

The regression model included all of study variables after adjustment for age and marital status. F-test and adjusted R 2 were conducted to assess model fit. Abbreviations: BDI-II, Beck Depression Inventory–II; BMI, Body Mass Index; HRQOL, Health-related Quality of Life measured by IWQOL–Lite; ISEL, Interpersonal Support Evaluation List; IWQOL, Impact of Weight on Quality of Life; WEL, Weight Efficacy Lifestyle. ∗ p < .05, ∗∗ p < .01. b

greater levels of obesity-specific HRQOL. In particular, the benefit of higher levels of self-efficacy for weight control was exhibited across all the HRQOL subscales, i.e., physical function, self-esteem, sexual life, public distress, and work. However, interpersonal social support was not significantly associated with obesity-specific HRQOL. We found that increased BMI was significantly associated with impairment in total IWQOL scores, although it was not significantly associated with all the subscales. In South Korea, the prevalence of overweight and obesity has gradually increased over the last 15 years. Among Koreans aged 19 years and over, 25.1% of men and 26.2% of women were overweight or obese in 1998. By 2012 this figure had risen to 36.1% of men and 29.9% of women (Ministry of Health & Welfare and Korea Center for Disease Control & Prevention 2013). In this context, impaired HRQOL associated with increased BMI may be a significant health issue to be addressed among the Korean population. Moreover, to the best of our knowledge, the present study is the first to report a significant association of BMI with total IWQOL in a multivariable-adjusted model; in particular, we reported significant associations between BMI and IWQOL scores among individuals who were mostly in the category of overweight (i.e., 76% of total participants). Although the IWQOL–Lite questionnaire is known to reflect weight-related HRQOL, most previous studies elucidated a significant relation of BMI to IWQOL among obese or morbidly obese individuals, specifically those awaiting bariatric surgery, compared to those having a normal-weight (Andrés et al. 2012; de A Mariano et al. 2010; Mueller et al. 2011). Our study adds to the body of knowledge about how excess weight is related to quality of life of women who are only overweight.

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We found that higher self-efficacy scores were significantly associated with higher HRQOL scores, independent of BMI, levels of depressive symptoms, and other covariates. This significant association was found across all the IWQOL–Lite subscales. To the best of our knowledge, our study is the first to report an association between self-efficacy and HRQOL among overweight and obese individuals or individuals seeking weight management. Previously, such a positive association between selfefficacy and HRQOL has been found in patients with chronic medical conditions, including stroke, chronic obstructive pulmonary disease, cancer, and spinal cord injuries (Kohler, Fish, and Greene 2002; Korpershoek, van der Bijl, and Hafsteinsdóttir 2011; Kreitler, Peleg, and Ehrenfeld 2007; Middleton, Tran, and Craig 2007). Based on those data, we suggest individuals with low levels of self-efficacy for controlling their medical condition may perceive their functioning in multiple domains as poorer than those with high levels of self-efficacy; this same belief may be true of overweight or obese individuals. Therefore, strategies focused on enhancing self-efficacy as a weight management intervention may be essential for improving HRQOL levels for those who are overweight and obese. The participants in our study exhibited a mean BDI–II score of 13.8 points, and 46% had mild or greater levels of depressive symptoms, based on that14.0 point cut-off score for the BDI–II. A solid body of literature exists demonstrating that individuals seeking weight management intervention exhibit depressive symptoms (Goldstein et al. 1996). Because depression has also been shown to be clinically associated with major, obesity-related diseases, such as coronary heart diseases and type II diabetes (Campayo et al. 2010; Nabi et al. 2010; Schnatz et al. 2011), these findings highlight the need for assessing levels of depressive symptoms among individuals seeking a weight management intervention. We found that higher levels of depressive symptoms were significantly and independently associated with lower levels of HRQOL. This finding was consistent with previous findings of an inverse association between depressive symptoms and HRQOL among obese adults (Fabricatore et al. 2005; Vetter et al. 2011). Vetter et al. (2011) demonstrated that in 390 obese individuals (82.5% female; mean BMI: 38.3 kg/m2 ), a higher level of depressive symptoms was associated with decreased HRQOL, as measured by obesity-specific IWQOL–Lite. Therefore, depressive symptoms for individuals seeking weight management intervention need to be alleviated to improve their HRQOL. Interpersonal social support, as measured by ISEL, was not significantly associated with obesity-specific HRQOL in a fully-adjusted model. This result may be due to the fact that depressive symptoms were significantly correlated (r = −0.49) with ISEL scores, and these depressive

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symptoms, in turn, may have been confounded with the significant association between social support and obesity-specific HRQOL. On the other hand, Herzer et al. reported that perceived social support was significantly associated with obesity-specific HRQOL in obese youth; this significant association may differ from ours because of different sources of support, i.e., close friends, parents, and teachers (Herzer et al. 2011). Further research is needed using various social support measures among overweight and obese individuals to identify the association between social support and HRQOL. A strength of our study is that this is the first study of which we are aware to reveal the relations of self-efficacy, depressive symptoms, and social support to HRQOL among female participants seeking weight management using an obesity-specific HRQOL measure. Limitations of our study included the cross-sectional nature of the study design, which made it impossible to assess the temporal direction of psychosocial factors in relation to HRQOL; a longitudinal approach would help to clarify these relations. In addition, we were unable to generalize our findings to males, the elderly, or other ethnic groups. Further, potential social acceptability bias was also possible, with respondents over- and under-rating their HRQOL as impaired. Moreover, it would be informative to carry out a further study with a larger sample size in the future. Finally, our findings support a conceptual link of self-efficacy and depressive symptoms to obesity-specific HRQOL among Korean women seeking weight management treatment, and also provide baseline data for designing strategies for improving HRQOL in a weight management intervention. One of the outcomes of weight management may be the improvement of an individual’s HRQOL. Along with strategies for weight loss, those for improving self-efficacy and alleviating depressive symptoms may be essential for improving HRQOL among overweight and obese women.

ACKNOWLEDGMENT The authors have no conflicts of interest to disclose.

FUNDING This research was supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology (No. 2010-0022022).

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Factors associated with health-related quality of life among overweight and obese Korean women.

Health-related quality of life (HRQOL) tends to be lower among individuals who are overweight and obese than those of normal weight, and women may be ...
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