Background
Depression and low perceived social support (PSS) have been found to deleteriously affect quality of life (QoL) among myocardial infarction (MI) survivors. The complex relationship between these variables has not been assessed. We wanted to assess first the prevalence of depression among MI survivors and whether depression mediates the effect of PSS on QoL and, second, whether the physical and social domains of QoL mediated the effect of depression and PSS on the emotional domain. This cross-sectional study was done among MI survivors using Cardiac Depression Scale, MacNew Quality of Life After Myocardial Infarction Questionnaire and Multidimensional Scale of Perceived Social Support to assess for depression, QoL and PSS respectively.
Results
A total of 103 MI survivors were included in the study, and the mean age was 59.66 (± 10.42) years. Depression was found in 21.36% of the participants. The indirect effect of PSS on QoL with depression as a mediator was significant (b = 0.15, p < 0.001, 95% CI = 0.12, 0.18). The direct effect of PSS on QoL controlling for depression was also significant (b = 0.05, p < 0.001, 95% CI = 0.02, 0.07). Depression as a mediator in the relationship explained 75.3% of the effect of PSS on QoL. PSS and depression did not have a significant direct effect on emotional QoL, but it became significant when the physical and social domains were included in the model. The total indirect effects of PSS and depression on emotional QoL were b = 0.16, p < 0.001, 95% CI = 0.05, 0.17 and b = − 0.05, p < 0.001, 95% CI = − 0.06, − 0.03, respectively.
Conclusion
Depression and poor PSS impair physical and social domains, which impairs the emotional domain of QoL; as such, overall QoL is undermined. As limited physical and social activity because of depression and poor PSS may increase the risk of further cardiovascular events, a holistic approach which includes mental health care is warranted.