Existing empirical literature on the prolonged or cumulative consequences of exposure to the stresses of caregiving is reviewed. Specific goals are to identify psychiatric and physical morbidity effects, report the magnitude of those effects, evaluate research and analytic methods used to assess morbidity, and make recommendations for future research. Overall, the literature indicates increases in self-report psychiatric symptomatology and increases in psychiatric illness among most caregivers when compared to population norms or appropriate control groups. However, there is little information on the population prevalence or incidence of clinically significant psychiatric conditions attributable to caregiving. Studies of physical health effects as assessed by self-report, health care utilization, and immune function are less conclusive but, nevertheless, suggest increased vulnerability to physical illness among caregivers. We conclude with a discussion of why morbidity effects are difficult to obtain in caregiver studies and with recommendations for future research.

Results from a 2-year (4 waves) longitudinal study show strong evidence for patient decline and high levels of depressive symptomatology among caregivers. Female caregivers reported high, stable rates of depressive symptomatology throughout the study, whereas male caregivers exhibited significant increases in depression over time. Cross-sectional multivariate analyses revealed significant positive relationships between depression and number of patient problem behaviors, negative social support, and concern about financial resources; negative relationships were found between depression and social support, quality of prior relationship, and satisfaction with social contacts. Three significant independent predictors of change in depression were found: Lower depression scores at Time 1 were related to increases in depression over time; men were more likely than women to experience increases; and a decline in social support resulted in increased depression.

Potentially harmful caregiver behavior is more likely in spouse caregiving situations and when care recipients have greater needs for care and caregivers are more cognitively impaired, have more physical symptoms, and are at risk for clinical depression. This risk profile is similar to that for negative caregiver outcomes.