Abstract
PURPOSE: High levels of depressive symptoms have been shown to affect the morbidity, mortality, and functioning of patients with myocardial infarction (MI). Findings have shown that social support is associated with depression in both patient and community samples. This study examined various aspects of social support as they relate to depressive symptoms in patients with MI, both in the hospital and 2 weeks later.
METHODS: As part of the Enhancing Recovery in Coronary Heart Disease (ENRICHD) pilot study, measures of perceived social support, social networks, social support received, and social conflict were administered to 196 patients with MI. These patients also were administered the Beck Depression Inventory and the Hamilton Rating Scale for Depression. Depression was reassessed 2 weeks later. Relations between social support indicators and the depression measures were examined.
RESULTS: The prevalence of depression symptoms was high, especially among poorer and younger patients. There was modest improvement across time. Patients with high social support scores, particularly those reflecting perceived support, had lower scores on depression measures at baseline. High levels of perceived support and low social conflict at baseline were associated with less follow-up depression, as measured by the Beck cognitive scale, but not the Beck somatic scale nor the Hamilton scale. There were few associations with measures of social networks and received support.
CONCLUSIONS: Social support indicators were differentially related to depression among patients with MI while in the hospital and 2 weeks later. The pattern of associations also depended on the measure of depression. A broad assessment strategy of both social support and depression is needed for a full understanding of their interrelations.
Depression has a high prevalence among patients with coronary artery disease, and it is associated with an elevated risk of mortality and morbidity. 1-5 Depression also has been shown to have important implications for other outcomes among cardiac patients such as disability, medical care utilization, and daily functioning. 6-9
Social support also predicts the survival of cardiac patients. 10-13 Furthermore, measures of social support are correlated negatively with depressive symptoms in both cross-sectional and prospective studies. 14,15 Relatively few studies have examined the interrelations of social support and depression in cardiac patients. Oxman and Hull 16 surveyed older heart surgery patients and found that perceived adequacy of support 1 month after surgery was related to depression measured at 6 months, but that perceived support during hospitalization did not relate to depression at 1 month. However, Brummett et al 17 observed that perceived support at the time of hospitalization was associated with improvements in depressive symptoms during the first month after hospitalization. A third study of community residents with cardiac illnesses showed improvements in depressive symptoms over periods up to 4 years among those with high levels of social support. 18 Another study of post-MI patients found that social support at the time of hospitalization predicted improvements in depression over a 1-year interval. 19
These observations are important because they point to ways that the adverse consequences of depression might be alleviated. Indeed, there are indications that the association between depression and mortality may be weaker among cardiac patients reporting more social support. 19
Although these previous studies are promising, they have not adequately addressed the complexities of social support because most have treated it as a unidimensional construct. Social support may have different consequences depending on what aspect of the construct is being measured. Perceived availability of social support can have a relation to depressive symptoms different from and sometimes opposite the support the respondents report receiving. 20,21 The sources of support also can be important. 20
Furthermore, not all aspects of social relationships are supportive or beneficial. Conflicts with friends and family should be taken into account when a patient's support network is evaluated because they can increase stress and depression. 18
Previous studies also have tended to rely on a single measure of depression. It is well known that different instruments measure different aspects of depression. In particular, clinical interviews elicit information different from that elicited by self-report symptom checklists. 21-23 Therefore, it would be desirable to have several depression measures to examine the effects of social support on more than one aspect of depressive symptomatology.
The current study, conducted in preparation for the Enhancing Recovery in Coronary Heart Disease (ENRICHD) trial, 24 was designed to provide a more comprehensive picture of the relations between social support and depression in post-MI patients at the time of hospitalization and during the initial posthospitalization period. Five measures of social support were administered during hospitalization along with a clinical interview and symptom checklist measures of depression. The depression measures were readministered 2 weeks later. Special attention was paid to potential differences attributable to gender, age, and income, factors that have been associated with the magnitude of depressive symptoms in previous studies of cardiac patients. 25-26