Effects of caregiver burden and satisfaction on affect of older end-stage renal disease patients and their spouses.

We examined the extent to which a 2-factor model of affect explains how the burdens and satisfactions experienced by caregivers influence their own well-being and that of the spouses for whom they provide care. Using data from 315 older patients with end-stage renal disease and their spouses, we extended tests of Lawton et al.'s (1991) 2-factor model both longitudinally and dyadically. Multilevel modeling analyses partially support the 2-factor model. Consistent with the model, mean caregiver burden has a stronger effect on both caregiver and patient negative affect than does mean caregiver satisfaction. Contrary to the model, mean caregiver satisfaction has an effect on caregiver positive affect that is similar to that of mean caregiver burden, and it has no effect on patient positive affect. Time-varying effects of caregiver burden are consistent with the 2-factor model for caregiver but not patient negative affect. Time-varying effects of caregiver satisfaction are not consistent with the 2-factor model for either patients or caregivers. Results highlight the powerful role of caregiver burden for both caregivers and patients and suggest important new directions for conducting health-related research with late-life marital dyads.