Rehabilitation Psychology 2014, Vol. 59, No. 2, 230-235
In the public domain DOl: 10.1037/a0036312
BRIEF REPORT
Social Support and Depressive Symptoms Among Caregivers of Veterans With Multiple Sclerosis Jennifer K. Bambara
Aaron P. Turner
VA Puget Sound Health Care System, Seattle, Washington
VA Puget Sound Health Care System, Seattle, Washington, VA MS Center of Excellence West, Seattle, Washington, and University of Washington
Rhonda M. Williams
Jodie K. Haselkom
VA Puget Sound Health Care System, Seattle, Washington and University of Washington
VA Puget Sound Health Care System, Seattle, Washington, VA MS Center of Excellence West, Seattle, Washington, and University of Washington
Purpose/Objective: The primary aim of this study was to examine the relationship between perceived social support and depressive symptoms among family caregivers of veterans with multiple sclerosis (MS). A secondary aim of this study was to examine the relationship between caregiver perceived social support and caregiver demographic variables, veteran health-related variables, and caregiver depressive symptoms. Research Method/Design: As part of a larger study, 42 family caregivers of veterans with MS completed questionnaires by telephone. Hierarchical regression was used to examine the relationship between caregiver depressive symptoms and perceived social support. Results: Greater MS disease severity and poorer overall veteran health were associated with higher levels of depressive symptoms among caregivers. Caregiver perceived social support was associated with depressive symptoms after controlling for veterans’ MS disease severity and overall physical health. Conclusions/Implications: Psychosocial interventions aimed at enhancing social support among caregivers of veterans with MS in multiple life domains, such as work, finances, housing, social life, marriage, and family, may be important for family caregiver mood management, particularly as MS disease severity increases. Keywords: multiple sclerosis, caregiver, social support, depression, veterans
• The study confirms that, even after controlling for veteran comorbid health conditions and greater MS disease severity, caregivers of veterans with MS who perceive more social support also report fewer depressive symptoms compared to those who perceive less support. • Providers should assess perceived social support among caregivers of veterans with MS and intervene to bolster caregiver support when indicated to minimize caregiver depressive symptoms.
Impact and Implications • Although veterans with multiple sclerosis (MS) often require assistance from family members, research examining this caregiving population is limited. This investigation extends the current caregiving literature by exploring the relationship between social support and depressive symptoms among family caregivers of veterans with MS.
Introduction This article was published Online First April 14, 2014. Jennifer K. Bambara, VA Puget Sound Health Care System, Seattle, Washington; Aaron P. Turner, VA Puget Sound Health Care System, VA MS Center of Excellence West, and Department of Rehabilitation Medi cine, University of Washington; Rhonda M. Williams, VA Puget Sound Health Care System, and Department of Rehabilitation Medicine, Univer sity of Washington; Jodie K. Haselkorn, VA Puget Sound Health Care System, VA MS Center of Excellence West, and Department of Rehabil itation Medicine and Epidemiology, University of Washington. This material is based upon work supported by VA Rehabilitation Research and Development Service Career Development grant (B4972W) awarded to Aaron P. Turner. Correspondence concerning this article should be addressed to Jennifer K. Bambara, PhD, Veterans Administration Puget Sound Health Care System, Seattle Division, Rehabilitation Care Services, S-117-RCS, 1660 S. Columbian Way, Seattle, WA 98108. E-mail: [email protected]
Multiple Sclerosis (MS) is a demyelinating and axonal disease with an unknown etiology that may be impacted by both genetic and environmental factors. Prevalence estimates in the United States range from 250,000 to 350,000 individuals (Noseworthy, Lucchinetti, Rodriguez, & Weinshenker, 2000). MS can impact functional abilities and psychosocial well-being (Williams et al., 2005; Zwibel & Smrtka, 2011), and individuals with MS often rely on assistance from family members who may receive little to no formal training or preparation (Dunn, 2010). Family members providing care to individuals with MS may be asked to manage the physical and emotional needs of the individ ual coping with an unpredictable disease course, address financial strains (lost wages, direct and indirect costs of disease manage ment), and navigate changes in relationships (lost intimacy with 230
MS CAREGIVER SUPPORT AND DEPRESSIVE SYMPTOMS
the person with MS, strained relations with other family members, and changes in family roles). There may also be additional care giving demands associated with assisting veterans with MS. Spe cifically, there is evidence to suggest that male veterans with MS age 50 and older have a higher prevalence of comorbid medical conditions compared to the general male population (Lavela, Pro haska, Fumer, & Weaver, 2012); male and female veterans with MS report greater levels of disability compared with nonveterans with MS (Lo, Hadjimichael, & Vollmer, 2005); and outpatients seeking care within the Veterans Affairs Health Care System (VA) report poorer health-related quality of life compared to those seeking outpatient services at non-VA facilities (Kazis et ah, 1998). Despite their efforts, family members caring for individuals with MS are often not compensated and are at risk for neglecting their own needs, interests, and personal/family relationships (Dunn, 2010). With new demands and responsibilities, it is perhaps not surprising that almost one third of MS caregivers experience clinically significant psychological distress (Pakenham, 2001). Social supports and stresses, used here to refer to one’s per ceived availability of support in multiple psychosocial domains, have been shown to impact one’s response to the caregiving role among those providing assistance to individuals with disabilities. For example, among adult family caregivers of stroke survivors, higher levels of social support were found to predict fewer depres sive symptoms (Grant et ah, 2006). Further, a meta-analysis by Pinquart and Sorensen (2011) examining family caregivers found that less informal social support was associated with more depres sive symptoms even after controlling for marital status and so ciodemographic variables. Conversely, there is evidence total life stresses can predict depression recurrence after controlling for demographic variables (Lethbridge & Allen, 2008). The strength of association between social supports and stresses and caregiver depressive symptoms is modest but consistent. It is important to consider that caregiver depression may impact both the caregiver and the care recipient. A longitudinal study by Smith, Williamson, Miller and Schulz (2011) found that increases in caregiver depres sive symptoms were associated with an increase in the frequency of potentially harmful behaviors when interacting with care recip ients (e.g., yelling, threatening nursing facility placement, etc.). While there is evidence to suggest that supports and strains are related to caregiver depressive symptoms, little is known about the relationship between perceived social support and depressive symptoms among caregivers of veterans with MS. This becomes important when one considers the many stressors caregivers of veterans with MS may face, including assisting individuals who may have multiple chronic medical issues in addition to MS and assisting individuals who report greater functional difficulties compared to the nonveteran MS population. The primary aim of this study was to examine the extent to which a measure of global social support would be associated with depressive symptoms among family caregivers of veterans with MS. We hypothesized that less perceived social support would be associated with greater depressive symptoms among caregivers of veterans with MS. A secondary aim of this study was to examine the relationship between caregiver perceptions of social support and caregiver demographic variables, Veteran health-related variables, and care giver depressive symptoms.
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Research Method Participants Participants were veterans recruited as part of a larger project examining medication adherence in MS, which has been de scribed in prior reports (Siegel, Turner, & Haselkorn, 2008; Turner, Williams, Sloan, & Haselkorn, 2009; Turner, Kivlahan, Sloan, & Haselkorn, 2007). Fifty-four of the 90 veterans re cruited from an outpatient MS clinic at a Veterans Affairs (VA) regional medical center identified individuals who provided at least some MS-related assistance. We chose to focus on family caregivers given the potential unique challenges faced by fam ily (vs. hired/formal) caregivers. Of the 54 identified caregiv ers, four were ineligible (formal/hired or “other” caregiver), eight declined to participate, so that 42 of 54 (78%) of care givers participated. Caregivers were adult family members (age a l 9 years) who provided some form of assistance to the individual with MS.
Procedure Veterans eligible for the study completed demographic, medi cal, and psychosocial questionnaires via interview. Participants were also asked to identify a primary caregiver, who was invited via letter to participate in the study. Consenting caregivers com pleted demographic and psychosocial measures via telephone. All study procedures were approved by the local institutional review board.
Measures Data gathered from veterans with MS. MS disease severity. The Mobility subscale of the Perfor mance Scales (Schwartz, Vollmer, & Lee, 1999) uses a single item to assess MS disease severity. Possible scores ranged from 0 (normal) to 6 (total gait disability). This measure has demonstrated excellent test-retest reliability (r = .91; Schwartz et a l, 1999). It is also highly correlated (r = .90) with the Expanded Disability Status Scale (Kurtzke, 1983), a well validated clinician-rating tool that provides an estimate of disease-related impairment and dis ability in persons with MS (Vollmer, Ni, Stanton, & Hadjimichael, 1999). Self-reported MS duration was assessed using a single item that inquired the year of diagnosis of MS. The difference between the year first diagnosed and the year the assessment was completed was used to indicate disease duration in years. Demographic and medical information. Demographic data (i.e., age, gender, race, education) were gathered from single-item questions. Overall physical health was assessed using the Seattle Index of Comorbidity (SIC), which combines information regard ing individuals’ comorbid health conditions (i.e., myocardial in farction, cancer, chronic obstructive pulmonary disease, conges tive heart failure, diabetes mellitus, pneumonia, and stroke), age, and tobacco use. Higher scores reflect more comorbid health conditions and an increased risk of hospitalization and mortality.
BAMBARA, TURNER, WILLIAMS, AND HASELKORN
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The SIC is a reliable and valid measure of health status among veteran populations (Fan et ah, 2002). Family caregiver data. Demographic information. Caregivers completed single-item demographic questions regarding their age, education, gender, race, and relationship to the veteran. Global social support. The Social Stress and Support Inter view (SSSI; Jenkins, Mann, & Belsey, 1981) was used to assess the degree of support perceived by family caregivers in the last 30 days across six life domains: occupation, finances, housing, social life, marriage, and family. Possible responses on this 6-item measure range from —1 (overall stress) to + 1 (overall support); thus, stress and support were considered to be at opposing ends of a continuum for each domain. A score of 0 reflects that neither stress nor support is experienced. Scores were summed so that the total score reflected global social support with higher scores reflecting greater perceived support. The SSSI has been used to assess perceived social support among those with MS (Korostil & Feinstein, 2007) and has demonstrated adequate internal consistency in the current sam ple (a = .70). Depressive symptoms. The Patient Health Questionnaire-9 (PHQ-9; Spitzer, Kroenke, & Williams, 1999) consists of nine items reflecting the symptoms of a major depressive episode. Individuals rate the frequency of the nine depressive symptoms over the last 2 weeks from 0 (not at all) to 3 (nearly every day). This is a continuous measure, with higher scores reflecting greater depressive symptomatology. The PHQ-9 demonstrated good internal consistency in the current sample (a = .81) and has established good test-retest reliability in the literature (r = .84 when administered within a 48-hr period; Kroenke, Spitzer, & Williams, 2001).
Analytic Strategy Hierarchical multiple regression was used to investigate the extent to which overall perceived support was related to de pressive symptoms among family caregivers of veterans with MS. As a first step, exploratory correlational analyses were conducted to examine the relationship between caregiver de mographic variables, veteran health-related variables, caregiver perceived social support, and caregiver depressive symptoms. Veteran age, gender, education, years with MS, and depressive symptoms, as well as caregiver age and gender were not asso ciated with caregiver depressive symptoms at a univariate level. Given the limited sample size of this study, only factors that were correlated with depressive symptoms (PHQ-9 score) at a univariate level were entered into the regression model exam ining depressive symptoms. A hierarchical regression equation was used to concurrently predict family caregiver depressive symptoms from veteran med ical variables and caregiver perceived social support. SIC scores and the Mobility subscale of the Performance Scales were signif icantly associated with caregiver depressive symptoms, and thus were entered in the first step of the regression equation. Family caregiver global social support was added at the second/final step. All analyses used the SPSS software Version 16.
Results Demographics Demographic characteristics of the veteran and caregiver sam ples are provided in Table 1.
Table 1 Demographic and Medical Characteristics o f Veterans With MS and Their Caregivers Characteristic Age, M (SD) Highest level of education, M (SD) Gender, n (%) Men Women Race/Ethnicity (may report more than one), n (%) Caucasian American Indian/native Alaskan African American Hawaiian/Pacific Islander Asian Other MS disease severity, M (SD) MS duration, M (SD) Caregiver relationship to the veteran, n (%) Spouse Sibling Son/daughter Parent Other relative # Comorbid chronic health conditions, M (SD) Note.
Veterans (n = 42) 51.5 (8.7) 15.0 (2.2)
Caregivers (n = 42) 51.6 (9.8) 13.8(2.7)
37 (88.1%) 5(11.9%)
4 (9.5%) 38 (90.5%)
39 (92.5%) 4 (9.5%) 3(7.1%) 0 (0%) 0 (0%) 3(7.1%) 3.3 (1.8) 12.7 (7.4)
37 (88.1%) 8 (19.0%) 1 (2.4%) 1 (2.4%) 0 (2.2%) 4 (9.6%)
2.6(1.9)
37 (88.1%) 1 (2.4%) 1 (2.4%) 1 (2.4%) 2 (4.8%)
Individuals could identify multiple racial/ethnic backgrounds. M = mean. SD = Standard deviation.
MS CAREGIVER SUPPORT AND DEPRESSIVE SYMPTOMS
Caregiver Perceived Social Support and Depressive Symptoms Mean perceived global social support reported by caregivers suggested that on average caregivers perceived slightly more so cial support than stress in the various life domains examined (see Table 2).
Univariate Correlates of Veteran Physical Health and Caregiver Perceived Support Table 2 contains the univariate correlations for the veteran MS disease severity and medical comorbidity, caregiver perceived global social support, and caregiver depressive symptoms. Poorer veteran physical health status was related to worse caregiver adjustment. Greater veteran medical comorbidity and greater MS disease severity were associated with greater depressive symptoms among caregivers.
Relationship of Caregiver Depressive Symptoms to MS Disease Severity and Veteran Physical Health The veterans’ number of comorbid medical conditions and MS disease severity were added at the first step and were concurrently predictive of caregiver depressive symptoms. At the second step, caregiver perceived social support was associated with lower lev els of depressive symptoms after controlling for veteran medical variables (see Table 3).
Relationship Between Amount of Social Support and Depressive Symptoms Qualitatively, caregivers with lower levels of social support (< median SSSI) reported a broad range of depressive symptoms. No caregivers who reported social support above the median on the SSSI scored above a 9 on the PHQ-9.
Discussion A better understanding of the relationship between perceived support and depressive symptoms among caregivers of veterans with MS becomes important when one considers the many de mands associated with this complex role. In this study, caregivers
Table 2 Correlations fo r Veteran Health Variables and Caregiver Self-Reported Psychosocial Variables Variables 1. 2. 3. 4.
MS Severity V-Comorbid C-SSSI C-PHQ-9
1
2
___
___
_
_
—
—
—
—
—
.07 -.0 5 .32*
-.2 2 .34*
3
- .45“’
4
-
M
SD
3.3 2.6 0.3 5.3
1.8 1.9 0.4 5.2
Note. M = mean; SD = Standard deviation; MS disease severity = Self-reported mobility disability (higher scores associated with greater disability); Comorbidity = Number of comorbid medical conditions; SSSI = Social Supports and Strains Interview; PHQ-9 = total score Patient Health Questionnaire-9; variables preceded with “V” indicate veteran variables; Variables preceded with “C” indicate caregiver variables. * Statistically significant (p < .05). ** Statistically significant (p < .01).
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Table 3 Multiple Regression o f Veterans ’ Overall Physical Health, Veterans’ MS Disease Severity, and Caregiver Perceived Support on Caregiver Depressive Symptoms Variable
ß
Caregiver depressive symptoms Step 1 MS Disease Severity V-SIC Step 2 C-SSSI
.3* .3*
F 1 inc
rl
^íotal
Ajd R2
5.05*
.20
.20
.17
7.82**
.14
.34
.29
-.4**
Note. Depressive symptoms = total score on Patient Health Question naire-9; SIC = Seattle Comorbidity Index score; SSSI = Social Stresses and Support Interview; variables preceded with “V” indicate veteran vari ables; variables preceded with “C” indicate caregiver variables; Adj R2 = Adjusted R squared. * Statistically significant (p < .05). ** Statistically significant (p < .01).
who perceived more available overall social support also reported fewer depressive symptoms compared to caregivers who perceived less support. This is consistent with the greater family caregiving literature. A meta-analysis by Schulz and Sherwood (2008) found that family caregivers with limited social support networks de scribed poorer psychological well-being compared to family care givers with more interpersonal resources. Our findings are also consistent with the MS social support literature, which has shown that those who perceived more overall social support also reported fewer depressive symptoms (Bambara, Turner, Williams, & Haselkom, 2011; Dennison, Moss-Morris, & Chalder, 2009). Another finding was that more veteran comorbid health condi tions and greater MS disease severity were associated with more caregiver depressive symptoms. This suggests that as the care recipient’s overall care requirements and medical complexities increase, this may adversely impact caregiver mood. It could be that as caregiving demands and stressors increase, family caregiv ers may need to expend more personal, financial, and social resources to meet the care recipient needs. Family caregivers may successfully adjust to the extent that they are able to access social support within and outside the home (Wakui, Saito, Agree, & Kai, 2012 ). The availability of, and access to, social support in a variety of life domains may reduce general life stress as well as caregiver burden. For example, flexibility from an employer may enable caregivers to attend to unpredictable care recipient needs, greater financial resources can increase the accessibility of applicable interventions, and distribution of caregiving responsibilities among multiple family members may provide time for the primary caregiver to engage in self-care. Clinicians should assess and monitor caregiver perceived social support prior to increasing caregiver demands. Interventions that enhance low levels of perceived social sup port may improve caregiver and veteran responsiveness to treat ment. Social support interventions have been shown to be more likely to improve caregiver well-being over time when both care recipient and the caregiver are involved in the intervention as compared to interventions targeting caregivers alone (Schulz et ah, 2009). In addition, a meta-analysis examining 52 randomized controlled trials of caregivers of individuals with cardiovascular
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disease, cancer, and arthritis revealed small but significant effects favoring family member involvement in interventions for individ uals with chronic medical conditions with a trend toward greater effects for relationship-focused family interventions as compared to educational interventions (Hartmann, Bazner, Wild, Eisler, & Herzog, 2010). Social support interventions incorporating veterans with MS and their caregivers may be particularly helpful, as greater perceived social suppoxt has been found to be related to fewer depressive symptoms among veterans with MS (Bambara et al., 2011), and it has been suggested that veterans with MS may benefit from social support enhancing interventions (Williams et al., 2005). Our results highlight the importance of perceived social support among family caregivers of veterans with MS. However, limita tions must also be acknowledged. The psychosocial self-report measures limit our ability to objectively assess the type and quality of social support; additionally, there was only one item measuring each type of perceived social support across the six social support domains examined. Future studies may include additional mea sures of perceived support and measures of the provision of support. Further, our adequate but small sample size precluded the use of more complex analyses that would require a more favorable subject to variable ratio. Another limitation of the study is the cross-sectional design, which limits the ability to examine these important and interrelated phenomena over time. The relationship between per ceived social support and caregiver depressive symptoms may be bidirectional. Future studies may utilize longitudinal designs to examine the extent to which low perceived social support contrib utes to depressive symptoms or whether depressive symptoms contribute to less perceived social support. Regarding possible concerns about generalizability, information was not collected regarding the veterans’ VA disability compensation. Future inves tigations exploring the relationship between veterans’ service con nection and VA service utilization may provide additional insights into caregiver supports and stresses among those assisting veterans with MS. Additionally, a formal measure of caregiver burden would have enhanced our understanding of factors that influence adjustment to caring for a family member with MS.
Conclusions Perceived social support is independently associated with MS caregiver depressive symptoms even after controlling for veteran overall physical health and MS disease severity. Additional re search is needed to examine temporal aspects of these relation ships. The inclusion of measures of caregiver burden will also enhance our understanding of care recipient and caregiver rela tionships. Clinical implications include assessing, monitoring, and providing psychosocial interventions to enhance perceived social support and minimize caregiver depressive symptoms.
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Clinical Psychology Review, 29, 141-153. doi: 10.1016/j.cpr.2008.12 .001 Dunn, J. (2010). Impact of mobility impairment on the burden of caregiv ing in individuals with multiple sclerosis. Expert Review o f Pharmacoeconomics & Outcomes Research, 10, 433-440. doi:10.1586/erp.l0.34 Fan, V. S., Au, D., Heagerty, P., Deyo, R., McDonell, M., & Fihn, S. (2002). Validation of case-mix measures derived from self-reports of diagnoses and health. Journal o f Clinical Epidemiology, 55, 371-380. doi:10.1016/S0895-4356(01)00493-0 Grant, J. S., Elliott, T. R., Weaver, M., Glandon, G. L., Râper, J. L., & Giger, J. N. (2006). Social problem-solving abilities, social support, and adjustment of family caregivers of stroke survivors. Archives o f Physical Medicine and Rehabilitation, 87, 343-350. doi:10.1016/j.apmr.2005.09 .019 Hartmann, M., Bazner, E., Wild, B., Eisler, I., & Herzog, W. (2010). Effects of interventions involving the family in the treatment of adult patients with chronic physical diseases: A meta-analysis. Psychotherapy and Psychosomatics, 79, 136-148. doi: 10.1159/000286958 Jenkins, R., Mann, A., & Belsey, E. (1981). The background, design, and use of a short interview to assess social stress and support in research and clinical settings. Social Science & Medicine. Part E: Medical Psy chology, 15, 195-203. Kazis, L. E., Miller, D. R., Clark, J., Skinner, K., Lee, A., Rogers, W .,. . . Linzer, M. (1998). Health-related quality of life in patients served by the Department of Veterans Affairs: Results From the Veterans Health Study. Archives o f Internal Medicine, 158, 626 - 632. doi:10.1001/ archinte. 158.6.626 Korostil, M., & Feinstein, A. (2007). Anxiety disorders and their clinical correlates in multiple sclerosis patients. Multiple Sclerosis Journal, 13, 67-72. doi: 10.1177/1352458506071161 Kroenke, K., Spitzer, R. L„ & Williams, J. B. (2001). The PHQ-9: Validity of a brief depression severity measure. Journal o f General Internal Medicine, 16, 606-613. doi:10.1046/j,1525-1497.2001.016009606.x Kurtzke, J. F. (1983). Rating neurological impairment in multiple sclerosis (MS): An Expanded Disability Status Scale (EDSS). Neurology, 33, 1444-1452. doi: 10.1212/WNL.33.11.1444 Lavela, S. L., Prohaska, T. R., Fumer, S., & Weaver, F. M. (2012). Chronic diseases in male veterans with multiple sclerosis. Preventing Chronic Disease, 9, 110121. doi: 10.5888/pcd9.110121 Lethbridge, R., & Allen, N. B. (2008). Mood induced cognitive and emotional reactivity, life stress, and the prediction of depressive relapse. Behaviour Research and Therapy, 46, 1142-1150. doi:10.1016/j.brat .2008.06.011 Lo, A. C., Hadjimichael, O., & Vollmer, T. L. (2005). Treatment patterns of multiple sclerosis patients: A comparison of veterans and non veterans using the NARCOMS registry. Multiple Sclerosis Journal, 11, 33-40. doi: 10.119 l/1352458505ms 1136oa Noseworthy, J. H., Lucchinetti, C., Rodriguez, M., & Weinshenker, B. G. (2000). Multiple sclerosis. The New England Journal o f Medicine, 343, 938-952. doi: 10.1056/NEJM200009283431307 Pakenham, K. I. (2001). Application of a stress and coping model to caregiving in multiple sclerosis. Psychology, Health & Medicine, 6, 13-27. doi: 10.1080/13548500125141 Pinquart, M., & Sorensen, S. (2011). Spouses, adult children, and childrenin-law as caregivers of older adults: A meta-analytic comparison. Psy chology and Aging, 26, 1—14. doi:10.1037/a0021863 Schulz, R., Czaja, S. J., Lustig, A., Zdaniuk, B., Marbre, L. M., & Perdomo, D. (2009). Improving the quality of life of caregivers of persons with spinal cord injury. A randomized controlled trial. Rehabil itation Psychology, 54, 1-15. doi:10.1037/a0014932 Schulz, R.. & Sherwood, P. R. (2008). Physical and mental health effects of family caregiving. American Journal o f Nursing, 108(9), 23-27. doi: 10.1097/01 .NAJ.0000336406.45248.4c
MS CAREGIVER SUPPORT AND DEPRESSIVE SYMPTOMS Schwartz, C. E., Vollmer, T., & Lee, H. (1999). Reliability and validity of two self-report measures of impairment and disability for MS. Neurol ogy, 52, 63-70. doi:10.1212/WNL.52.1.63 Siegel, S. D., Turner, A. P., & Haselkom, J. K. (2008). Adherence to disease-modifying therapies in multiple sclerosis: Does caregiver social support matter? Rehabilitation Psychology, 53, 73-79. doi: 10.1037/ 0090-5550.53.1.73 Smith, G. R„ Williamson, G. M„ Miller, L. S., & Schulz, R. (2011). Depression and quality of informal care: A longitudinal investigation of caregiving stressors. Psychology and Aging, 26, 584-591. doi:10.1037/ a0022263 Spitzer, R. L., Kroenke, K., & Williams, J. (1999). Validation and utility of a self-report version of the PRIME-MD: The PHQ primary care study. Primary care evaluation of mental disorders, Patient Health Question naire. Journal of the American Medical Association, 282, 1737-1744. doi:10.1001/jama.282.18.1737 Turner, A. P., Kivlahan, D. R., Sloan, A. P., & Haselkom, J. K. (2007). Predicting ongoing adherence to disease modifying therapies in multiple sclerosis: Utility of the health beliefs model. Multiple Sclerosis Journal, 13, 1146-1152. doi: 10.1177/1352458507078911 Turner, A. P., Williams, R. M., Sloan, A. P., & Haselkom, J. K. (2009). Injection anxiety remains a long-term barrier to medication adherence in
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multiple sclerosis. Rehabilitation Psychology, 54, 116-121. doi: 10.1037/a0014460 Vollmer, T. L., Ni, W., Stanton, S., & Hadjimichael, O. (1999). The NARCOMS Patient Registry: A resource for investigators. International Journal of MS Care, 1, 28-34. doi:10.7224/1537-2073-1.1.28 Wakui, T., Saito, T„ Agree, E. M„ & Kai, I. (2012). Effects of home, outside leisure, social, and peer activity on psychological health among Japanese family caregivers. Aging & Mental Health, 16, 500-506. doi: 10.1080/13607863.2011.644263 Williams, R. M., Turner, A. P., Hatzakis, M., Jr., Bowen, J. D., Rodriquez, A. A., & Haselkom, J. K. (2005). Prevalence and correlates of depres sion among veterans with multiple sclerosis. Neurology, 64, 75-80. doi: 10.1212/01. WNL.0000148480.31424.2A Zwibel, H. L., & Smrtka, J. (2011). Improving quality of life in multiple sclerosis: An unmet need. American Journal o f Managed Care, 17, S139-S145.
Received May 27, 2013 Revision received February 10, 2014 Accepted February 10, 2014 ■
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In the public domain DOl: 10.1037/a0036312
BRIEF REPORT
Social Support and Depressive Symptoms Among Caregivers of Veterans With Multiple Sclerosis Jennifer K. Bambara
Aaron P. Turner
VA Puget Sound Health Care System, Seattle, Washington
VA Puget Sound Health Care System, Seattle, Washington, VA MS Center of Excellence West, Seattle, Washington, and University of Washington
Rhonda M. Williams
Jodie K. Haselkom
VA Puget Sound Health Care System, Seattle, Washington and University of Washington
VA Puget Sound Health Care System, Seattle, Washington, VA MS Center of Excellence West, Seattle, Washington, and University of Washington
Purpose/Objective: The primary aim of this study was to examine the relationship between perceived social support and depressive symptoms among family caregivers of veterans with multiple sclerosis (MS). A secondary aim of this study was to examine the relationship between caregiver perceived social support and caregiver demographic variables, veteran health-related variables, and caregiver depressive symptoms. Research Method/Design: As part of a larger study, 42 family caregivers of veterans with MS completed questionnaires by telephone. Hierarchical regression was used to examine the relationship between caregiver depressive symptoms and perceived social support. Results: Greater MS disease severity and poorer overall veteran health were associated with higher levels of depressive symptoms among caregivers. Caregiver perceived social support was associated with depressive symptoms after controlling for veterans’ MS disease severity and overall physical health. Conclusions/Implications: Psychosocial interventions aimed at enhancing social support among caregivers of veterans with MS in multiple life domains, such as work, finances, housing, social life, marriage, and family, may be important for family caregiver mood management, particularly as MS disease severity increases. Keywords: multiple sclerosis, caregiver, social support, depression, veterans
• The study confirms that, even after controlling for veteran comorbid health conditions and greater MS disease severity, caregivers of veterans with MS who perceive more social support also report fewer depressive symptoms compared to those who perceive less support. • Providers should assess perceived social support among caregivers of veterans with MS and intervene to bolster caregiver support when indicated to minimize caregiver depressive symptoms.
Impact and Implications • Although veterans with multiple sclerosis (MS) often require assistance from family members, research examining this caregiving population is limited. This investigation extends the current caregiving literature by exploring the relationship between social support and depressive symptoms among family caregivers of veterans with MS.
Introduction This article was published Online First April 14, 2014. Jennifer K. Bambara, VA Puget Sound Health Care System, Seattle, Washington; Aaron P. Turner, VA Puget Sound Health Care System, VA MS Center of Excellence West, and Department of Rehabilitation Medi cine, University of Washington; Rhonda M. Williams, VA Puget Sound Health Care System, and Department of Rehabilitation Medicine, Univer sity of Washington; Jodie K. Haselkorn, VA Puget Sound Health Care System, VA MS Center of Excellence West, and Department of Rehabil itation Medicine and Epidemiology, University of Washington. This material is based upon work supported by VA Rehabilitation Research and Development Service Career Development grant (B4972W) awarded to Aaron P. Turner. Correspondence concerning this article should be addressed to Jennifer K. Bambara, PhD, Veterans Administration Puget Sound Health Care System, Seattle Division, Rehabilitation Care Services, S-117-RCS, 1660 S. Columbian Way, Seattle, WA 98108. E-mail: [email protected]
Multiple Sclerosis (MS) is a demyelinating and axonal disease with an unknown etiology that may be impacted by both genetic and environmental factors. Prevalence estimates in the United States range from 250,000 to 350,000 individuals (Noseworthy, Lucchinetti, Rodriguez, & Weinshenker, 2000). MS can impact functional abilities and psychosocial well-being (Williams et al., 2005; Zwibel & Smrtka, 2011), and individuals with MS often rely on assistance from family members who may receive little to no formal training or preparation (Dunn, 2010). Family members providing care to individuals with MS may be asked to manage the physical and emotional needs of the individ ual coping with an unpredictable disease course, address financial strains (lost wages, direct and indirect costs of disease manage ment), and navigate changes in relationships (lost intimacy with 230
MS CAREGIVER SUPPORT AND DEPRESSIVE SYMPTOMS
the person with MS, strained relations with other family members, and changes in family roles). There may also be additional care giving demands associated with assisting veterans with MS. Spe cifically, there is evidence to suggest that male veterans with MS age 50 and older have a higher prevalence of comorbid medical conditions compared to the general male population (Lavela, Pro haska, Fumer, & Weaver, 2012); male and female veterans with MS report greater levels of disability compared with nonveterans with MS (Lo, Hadjimichael, & Vollmer, 2005); and outpatients seeking care within the Veterans Affairs Health Care System (VA) report poorer health-related quality of life compared to those seeking outpatient services at non-VA facilities (Kazis et ah, 1998). Despite their efforts, family members caring for individuals with MS are often not compensated and are at risk for neglecting their own needs, interests, and personal/family relationships (Dunn, 2010). With new demands and responsibilities, it is perhaps not surprising that almost one third of MS caregivers experience clinically significant psychological distress (Pakenham, 2001). Social supports and stresses, used here to refer to one’s per ceived availability of support in multiple psychosocial domains, have been shown to impact one’s response to the caregiving role among those providing assistance to individuals with disabilities. For example, among adult family caregivers of stroke survivors, higher levels of social support were found to predict fewer depres sive symptoms (Grant et ah, 2006). Further, a meta-analysis by Pinquart and Sorensen (2011) examining family caregivers found that less informal social support was associated with more depres sive symptoms even after controlling for marital status and so ciodemographic variables. Conversely, there is evidence total life stresses can predict depression recurrence after controlling for demographic variables (Lethbridge & Allen, 2008). The strength of association between social supports and stresses and caregiver depressive symptoms is modest but consistent. It is important to consider that caregiver depression may impact both the caregiver and the care recipient. A longitudinal study by Smith, Williamson, Miller and Schulz (2011) found that increases in caregiver depres sive symptoms were associated with an increase in the frequency of potentially harmful behaviors when interacting with care recip ients (e.g., yelling, threatening nursing facility placement, etc.). While there is evidence to suggest that supports and strains are related to caregiver depressive symptoms, little is known about the relationship between perceived social support and depressive symptoms among caregivers of veterans with MS. This becomes important when one considers the many stressors caregivers of veterans with MS may face, including assisting individuals who may have multiple chronic medical issues in addition to MS and assisting individuals who report greater functional difficulties compared to the nonveteran MS population. The primary aim of this study was to examine the extent to which a measure of global social support would be associated with depressive symptoms among family caregivers of veterans with MS. We hypothesized that less perceived social support would be associated with greater depressive symptoms among caregivers of veterans with MS. A secondary aim of this study was to examine the relationship between caregiver perceptions of social support and caregiver demographic variables, Veteran health-related variables, and care giver depressive symptoms.
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Research Method Participants Participants were veterans recruited as part of a larger project examining medication adherence in MS, which has been de scribed in prior reports (Siegel, Turner, & Haselkorn, 2008; Turner, Williams, Sloan, & Haselkorn, 2009; Turner, Kivlahan, Sloan, & Haselkorn, 2007). Fifty-four of the 90 veterans re cruited from an outpatient MS clinic at a Veterans Affairs (VA) regional medical center identified individuals who provided at least some MS-related assistance. We chose to focus on family caregivers given the potential unique challenges faced by fam ily (vs. hired/formal) caregivers. Of the 54 identified caregiv ers, four were ineligible (formal/hired or “other” caregiver), eight declined to participate, so that 42 of 54 (78%) of care givers participated. Caregivers were adult family members (age a l 9 years) who provided some form of assistance to the individual with MS.
Procedure Veterans eligible for the study completed demographic, medi cal, and psychosocial questionnaires via interview. Participants were also asked to identify a primary caregiver, who was invited via letter to participate in the study. Consenting caregivers com pleted demographic and psychosocial measures via telephone. All study procedures were approved by the local institutional review board.
Measures Data gathered from veterans with MS. MS disease severity. The Mobility subscale of the Perfor mance Scales (Schwartz, Vollmer, & Lee, 1999) uses a single item to assess MS disease severity. Possible scores ranged from 0 (normal) to 6 (total gait disability). This measure has demonstrated excellent test-retest reliability (r = .91; Schwartz et a l, 1999). It is also highly correlated (r = .90) with the Expanded Disability Status Scale (Kurtzke, 1983), a well validated clinician-rating tool that provides an estimate of disease-related impairment and dis ability in persons with MS (Vollmer, Ni, Stanton, & Hadjimichael, 1999). Self-reported MS duration was assessed using a single item that inquired the year of diagnosis of MS. The difference between the year first diagnosed and the year the assessment was completed was used to indicate disease duration in years. Demographic and medical information. Demographic data (i.e., age, gender, race, education) were gathered from single-item questions. Overall physical health was assessed using the Seattle Index of Comorbidity (SIC), which combines information regard ing individuals’ comorbid health conditions (i.e., myocardial in farction, cancer, chronic obstructive pulmonary disease, conges tive heart failure, diabetes mellitus, pneumonia, and stroke), age, and tobacco use. Higher scores reflect more comorbid health conditions and an increased risk of hospitalization and mortality.
BAMBARA, TURNER, WILLIAMS, AND HASELKORN
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The SIC is a reliable and valid measure of health status among veteran populations (Fan et ah, 2002). Family caregiver data. Demographic information. Caregivers completed single-item demographic questions regarding their age, education, gender, race, and relationship to the veteran. Global social support. The Social Stress and Support Inter view (SSSI; Jenkins, Mann, & Belsey, 1981) was used to assess the degree of support perceived by family caregivers in the last 30 days across six life domains: occupation, finances, housing, social life, marriage, and family. Possible responses on this 6-item measure range from —1 (overall stress) to + 1 (overall support); thus, stress and support were considered to be at opposing ends of a continuum for each domain. A score of 0 reflects that neither stress nor support is experienced. Scores were summed so that the total score reflected global social support with higher scores reflecting greater perceived support. The SSSI has been used to assess perceived social support among those with MS (Korostil & Feinstein, 2007) and has demonstrated adequate internal consistency in the current sam ple (a = .70). Depressive symptoms. The Patient Health Questionnaire-9 (PHQ-9; Spitzer, Kroenke, & Williams, 1999) consists of nine items reflecting the symptoms of a major depressive episode. Individuals rate the frequency of the nine depressive symptoms over the last 2 weeks from 0 (not at all) to 3 (nearly every day). This is a continuous measure, with higher scores reflecting greater depressive symptomatology. The PHQ-9 demonstrated good internal consistency in the current sample (a = .81) and has established good test-retest reliability in the literature (r = .84 when administered within a 48-hr period; Kroenke, Spitzer, & Williams, 2001).
Analytic Strategy Hierarchical multiple regression was used to investigate the extent to which overall perceived support was related to de pressive symptoms among family caregivers of veterans with MS. As a first step, exploratory correlational analyses were conducted to examine the relationship between caregiver de mographic variables, veteran health-related variables, caregiver perceived social support, and caregiver depressive symptoms. Veteran age, gender, education, years with MS, and depressive symptoms, as well as caregiver age and gender were not asso ciated with caregiver depressive symptoms at a univariate level. Given the limited sample size of this study, only factors that were correlated with depressive symptoms (PHQ-9 score) at a univariate level were entered into the regression model exam ining depressive symptoms. A hierarchical regression equation was used to concurrently predict family caregiver depressive symptoms from veteran med ical variables and caregiver perceived social support. SIC scores and the Mobility subscale of the Performance Scales were signif icantly associated with caregiver depressive symptoms, and thus were entered in the first step of the regression equation. Family caregiver global social support was added at the second/final step. All analyses used the SPSS software Version 16.
Results Demographics Demographic characteristics of the veteran and caregiver sam ples are provided in Table 1.
Table 1 Demographic and Medical Characteristics o f Veterans With MS and Their Caregivers Characteristic Age, M (SD) Highest level of education, M (SD) Gender, n (%) Men Women Race/Ethnicity (may report more than one), n (%) Caucasian American Indian/native Alaskan African American Hawaiian/Pacific Islander Asian Other MS disease severity, M (SD) MS duration, M (SD) Caregiver relationship to the veteran, n (%) Spouse Sibling Son/daughter Parent Other relative # Comorbid chronic health conditions, M (SD) Note.
Veterans (n = 42) 51.5 (8.7) 15.0 (2.2)
Caregivers (n = 42) 51.6 (9.8) 13.8(2.7)
37 (88.1%) 5(11.9%)
4 (9.5%) 38 (90.5%)
39 (92.5%) 4 (9.5%) 3(7.1%) 0 (0%) 0 (0%) 3(7.1%) 3.3 (1.8) 12.7 (7.4)
37 (88.1%) 8 (19.0%) 1 (2.4%) 1 (2.4%) 0 (2.2%) 4 (9.6%)
2.6(1.9)
37 (88.1%) 1 (2.4%) 1 (2.4%) 1 (2.4%) 2 (4.8%)
Individuals could identify multiple racial/ethnic backgrounds. M = mean. SD = Standard deviation.
MS CAREGIVER SUPPORT AND DEPRESSIVE SYMPTOMS
Caregiver Perceived Social Support and Depressive Symptoms Mean perceived global social support reported by caregivers suggested that on average caregivers perceived slightly more so cial support than stress in the various life domains examined (see Table 2).
Univariate Correlates of Veteran Physical Health and Caregiver Perceived Support Table 2 contains the univariate correlations for the veteran MS disease severity and medical comorbidity, caregiver perceived global social support, and caregiver depressive symptoms. Poorer veteran physical health status was related to worse caregiver adjustment. Greater veteran medical comorbidity and greater MS disease severity were associated with greater depressive symptoms among caregivers.
Relationship of Caregiver Depressive Symptoms to MS Disease Severity and Veteran Physical Health The veterans’ number of comorbid medical conditions and MS disease severity were added at the first step and were concurrently predictive of caregiver depressive symptoms. At the second step, caregiver perceived social support was associated with lower lev els of depressive symptoms after controlling for veteran medical variables (see Table 3).
Relationship Between Amount of Social Support and Depressive Symptoms Qualitatively, caregivers with lower levels of social support (< median SSSI) reported a broad range of depressive symptoms. No caregivers who reported social support above the median on the SSSI scored above a 9 on the PHQ-9.
Discussion A better understanding of the relationship between perceived support and depressive symptoms among caregivers of veterans with MS becomes important when one considers the many de mands associated with this complex role. In this study, caregivers
Table 2 Correlations fo r Veteran Health Variables and Caregiver Self-Reported Psychosocial Variables Variables 1. 2. 3. 4.
MS Severity V-Comorbid C-SSSI C-PHQ-9
1
2
___
___
_
_
—
—
—
—
—
.07 -.0 5 .32*
-.2 2 .34*
3
- .45“’
4
-
M
SD
3.3 2.6 0.3 5.3
1.8 1.9 0.4 5.2
Note. M = mean; SD = Standard deviation; MS disease severity = Self-reported mobility disability (higher scores associated with greater disability); Comorbidity = Number of comorbid medical conditions; SSSI = Social Supports and Strains Interview; PHQ-9 = total score Patient Health Questionnaire-9; variables preceded with “V” indicate veteran variables; Variables preceded with “C” indicate caregiver variables. * Statistically significant (p < .05). ** Statistically significant (p < .01).
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Table 3 Multiple Regression o f Veterans ’ Overall Physical Health, Veterans’ MS Disease Severity, and Caregiver Perceived Support on Caregiver Depressive Symptoms Variable
ß
Caregiver depressive symptoms Step 1 MS Disease Severity V-SIC Step 2 C-SSSI
.3* .3*
F 1 inc
rl
^íotal
Ajd R2
5.05*
.20
.20
.17
7.82**
.14
.34
.29
-.4**
Note. Depressive symptoms = total score on Patient Health Question naire-9; SIC = Seattle Comorbidity Index score; SSSI = Social Stresses and Support Interview; variables preceded with “V” indicate veteran vari ables; variables preceded with “C” indicate caregiver variables; Adj R2 = Adjusted R squared. * Statistically significant (p < .05). ** Statistically significant (p < .01).
who perceived more available overall social support also reported fewer depressive symptoms compared to caregivers who perceived less support. This is consistent with the greater family caregiving literature. A meta-analysis by Schulz and Sherwood (2008) found that family caregivers with limited social support networks de scribed poorer psychological well-being compared to family care givers with more interpersonal resources. Our findings are also consistent with the MS social support literature, which has shown that those who perceived more overall social support also reported fewer depressive symptoms (Bambara, Turner, Williams, & Haselkom, 2011; Dennison, Moss-Morris, & Chalder, 2009). Another finding was that more veteran comorbid health condi tions and greater MS disease severity were associated with more caregiver depressive symptoms. This suggests that as the care recipient’s overall care requirements and medical complexities increase, this may adversely impact caregiver mood. It could be that as caregiving demands and stressors increase, family caregiv ers may need to expend more personal, financial, and social resources to meet the care recipient needs. Family caregivers may successfully adjust to the extent that they are able to access social support within and outside the home (Wakui, Saito, Agree, & Kai, 2012 ). The availability of, and access to, social support in a variety of life domains may reduce general life stress as well as caregiver burden. For example, flexibility from an employer may enable caregivers to attend to unpredictable care recipient needs, greater financial resources can increase the accessibility of applicable interventions, and distribution of caregiving responsibilities among multiple family members may provide time for the primary caregiver to engage in self-care. Clinicians should assess and monitor caregiver perceived social support prior to increasing caregiver demands. Interventions that enhance low levels of perceived social sup port may improve caregiver and veteran responsiveness to treat ment. Social support interventions have been shown to be more likely to improve caregiver well-being over time when both care recipient and the caregiver are involved in the intervention as compared to interventions targeting caregivers alone (Schulz et ah, 2009). In addition, a meta-analysis examining 52 randomized controlled trials of caregivers of individuals with cardiovascular
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disease, cancer, and arthritis revealed small but significant effects favoring family member involvement in interventions for individ uals with chronic medical conditions with a trend toward greater effects for relationship-focused family interventions as compared to educational interventions (Hartmann, Bazner, Wild, Eisler, & Herzog, 2010). Social support interventions incorporating veterans with MS and their caregivers may be particularly helpful, as greater perceived social suppoxt has been found to be related to fewer depressive symptoms among veterans with MS (Bambara et al., 2011), and it has been suggested that veterans with MS may benefit from social support enhancing interventions (Williams et al., 2005). Our results highlight the importance of perceived social support among family caregivers of veterans with MS. However, limita tions must also be acknowledged. The psychosocial self-report measures limit our ability to objectively assess the type and quality of social support; additionally, there was only one item measuring each type of perceived social support across the six social support domains examined. Future studies may include additional mea sures of perceived support and measures of the provision of support. Further, our adequate but small sample size precluded the use of more complex analyses that would require a more favorable subject to variable ratio. Another limitation of the study is the cross-sectional design, which limits the ability to examine these important and interrelated phenomena over time. The relationship between per ceived social support and caregiver depressive symptoms may be bidirectional. Future studies may utilize longitudinal designs to examine the extent to which low perceived social support contrib utes to depressive symptoms or whether depressive symptoms contribute to less perceived social support. Regarding possible concerns about generalizability, information was not collected regarding the veterans’ VA disability compensation. Future inves tigations exploring the relationship between veterans’ service con nection and VA service utilization may provide additional insights into caregiver supports and stresses among those assisting veterans with MS. Additionally, a formal measure of caregiver burden would have enhanced our understanding of factors that influence adjustment to caring for a family member with MS.
Conclusions Perceived social support is independently associated with MS caregiver depressive symptoms even after controlling for veteran overall physical health and MS disease severity. Additional re search is needed to examine temporal aspects of these relation ships. The inclusion of measures of caregiver burden will also enhance our understanding of care recipient and caregiver rela tionships. Clinical implications include assessing, monitoring, and providing psychosocial interventions to enhance perceived social support and minimize caregiver depressive symptoms.
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multiple sclerosis. Rehabilitation Psychology, 54, 116-121. doi: 10.1037/a0014460 Vollmer, T. L., Ni, W., Stanton, S., & Hadjimichael, O. (1999). The NARCOMS Patient Registry: A resource for investigators. International Journal of MS Care, 1, 28-34. doi:10.7224/1537-2073-1.1.28 Wakui, T., Saito, T„ Agree, E. M„ & Kai, I. (2012). Effects of home, outside leisure, social, and peer activity on psychological health among Japanese family caregivers. Aging & Mental Health, 16, 500-506. doi: 10.1080/13607863.2011.644263 Williams, R. M., Turner, A. P., Hatzakis, M., Jr., Bowen, J. D., Rodriquez, A. A., & Haselkom, J. K. (2005). Prevalence and correlates of depres sion among veterans with multiple sclerosis. Neurology, 64, 75-80. doi: 10.1212/01. WNL.0000148480.31424.2A Zwibel, H. L., & Smrtka, J. (2011). Improving quality of life in multiple sclerosis: An unmet need. American Journal o f Managed Care, 17, S139-S145.
Received May 27, 2013 Revision received February 10, 2014 Accepted February 10, 2014 ■
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