Effect of Depressive Symptoms Change and Social Support Change on Self-Care Behaviors Among Low-Income, Predominantly Hispanic Patients: A Longitudinal Study

Background: Self-care behaviors are recommended to any diabetes patients for better health. Comorbid depression and lack of social support are known risk factors undermining self-care behaviors. A variety of psychosocial programs have been developed to treat depression and activate social support.  Yet, empirical evidence still lacks to answer to whether depressive symptoms change and social support change are responsible for improved self-care behaviors in these programs. Existing studies offer mixed findings at best. We conducted a longitudinal study that examined relationships between depressive symptoms change and social support change, and self-care behaviors with data collected from a randomized clinical trial (RCT) testing effectiveness of promotora-led intervention. Self-efficacy to manage diabetes and adherence to self-care behaviors were outcomes.

Methods: Among data of 333 patients at baseline, 251 (75.38%) Hispanic patients were analyzed for this study. Patients were recruited from three federally qualified health centers in inner city Los Angeles inner city. The study analyzed data from patients who completed a baseline and a 6-month follow-up surveys. Participants had to be diagnosed with diabetes and were screened for depression with the Patient Health Questionnaire-9 (PHQ-9; cutoff ≥10). 82 patients (24.62%) didn’t complete the 6-month survey, and no difference of demographic and clinical factors at baseline were found compared to the analyzed group. Depressive symptoms were measured with PHQ-9. Social support was measured with Medical Outcomes Study (MOS) Social Support Survey and this tool has two subdomains, including instrumental social support and emotional social support. Difference between values between at a baseline and a 6-month follow-up surveys were calculated to find changes in depressive symptoms, social support, instrumental social support, and emotional social support. Self-Efficacy for Managing Chronic Disease measured self-efficacy. Lastly, 9 items from MOS Specific Adherence Recommendations and Behaviors measured adherence to self-care behaviors. Two hierarchical models were examined with self-efficacy and adherence to self-care behaviors, which were measured at 6-month follow-up. Each hierarchical regression model had four models that examined a set of covariates and baseline value of the outcomes: depressive symptoms change, social support change, and changes in instrumental and emotional social support. For significance tests, we used 0.05 as the rejection level.

Results: The hierarchical regression model focusing on self-efficacy at 6 month-follow-up found a decline in depressive symptoms (p<.001), increased social support (p<.01) and increased emotional social support (p<.05) were significantly correlated with the outcome, yet instrumental social support was not (p>.05). Another hierarchical regression model with adherence to self-care behaviors at 6-month follow-up demonstrated that decline in depressive symptoms were correlated with higher adherence level (p<.01). However, no significant relationship was observed with social support change (p>.05), instrumental social support change (p>.05) and emotional social support change (p>.05).

Conclusions: Treating depression symptoms is an important component in programs that intend to improve self-efficacy in the management of chronic disease and adherence to self-care behaviors.  This study suggests social support change is important to improve self-efficacy, yet not for self-care behaviors. Further studies with different ways in measuring adherence to self-care behaviors and social relationships are recommended.