Association Between Chronic Caregiving Stress and Impaired Endothelial Function in the Elderly

OBJECTIVES: We examined the relationship between chronic caregiving stress and endothelial function. BACKGROUND: Evidence suggests that caregiving stress is associated with pathophysiologic processes related to atherosclerosis. Endothelial dysfunction is a possible underlying mechanism explaining the relationship between caregiving stress and cardiovascular morbidity. We investigated the relationship between chronic caregiving stress and endothelial dysfunction assessed by reactive hyperemia-induced flow-mediated dilation (FMD). METHODS: Seventy-eight elderly individuals participated in the study. Fifty-five were providing in-home care to a spouse with Alzheimer's disease, and 23 were married and living with a healthy, nondemented spouse. Analysis of covariance was used to examine the relationships between advancing dementia severity (Clinical Dementia Rating scores) and FMD and nitroglycerin-induced vasodilation of the brachial artery. Multiple linear regression was used to examine the relationship between years of caregiving and FMD. RESULTS: Clinical Dementia Rating scale scores were significantly related to FMD (p = 0.033), with participants caring for a spouse with moderate to severe dementia showing significantly worse FMD than those caring for a spouse with mild dementia (p = 0.028) and noncaregivers (p = 0.032). Within the caregiver sample, the number of years of caregiving was significantly related to FMD (r = -0.465, p < 0.001). CONCLUSIONS: These results suggest that the chronic stress of caregiving is associated with impaired endothelial function, which may be a potential mechanistic link to the observed increased risk of cardiovascular disease in elderly caregivers.