The concept of “social support” and its relation to health outcomes has been a focus of study in psychosocial epidemiology for over 25 years. The intuitive sense that high levels of social support protect people from disease and early death has not always been realized in epidemiologic studies. In the history of this research, the goal has generally been to determine whether some measure of social support is an “independent” predictor of all-cause mortality or disease-specific mortality and morbidity. The strongest evidence that social support is related to health or disease comes from studies of large populations demonstrating that social support or social networks are protective against all-cause mortality. It also appears that social support is negatively associated with cardiovascular death and that it protects against recurrent events and death among persons diagnosed with disease.
Research involving the predictive relation between social support/social networks and incidence of disease, specifically cardiovascular disease, has been inconclusive and inconsistent. Study results linking social support/networks to cancer and other outcomes, such as survival from human immunodeficiency virus/acquired immunodeficiency syndrome and complications arising during pregnancy, have also been conflicting.
Inconsistencies in the findings surrounding social support/networks and physical health outcomes may result from a number of factors. First, social support/networks are defined and measured differently across studies. Second, the association between social support and health may be not unidirectional but bidirectional; for example, in some circumstances, social support may be counterproductive to healthy outcomes. Third, the effects of social support may vary by characteristics such as age, sex, socioeconomic status, cultural setting, disease, or stage of disease. Fourth, the mechanisms that may explain any associations between social support and health need further elucidation. Fifth, theoretical paradigms need to be clearly defined and utilized in designing studies and analyzing data. Lastly, automatic multivariable adjustment, as practiced in many pidemiologic studies, may not be conducive to understanding the effects of social support on health outcomes.