Background: Studies of caregiver burden and somatic illness tend to be based on relatively small, clinical samples. Longitudinal, population based studies on this topic are still scarce and little is known about the long-term impact of partner illness on spousal mental health in the general population. In this study we investigate whether spouses of partners who either have become somatically ill or cured from illness in an 11 year period - or who have long-term illness - have different mental health scores compared to spouses of healthy partners.
Methods: Approximately 9000 couples with valid self-report data on a Global Mental Health (GMH) scale and somatic illness status were identified. The diagnoses stroke, angina pectoris, myocardial infarction and severe physical disability, were transformed into a dichotomous 'any illness'-scale, and also investigated separately. Analyses of variance (ANOVA) stratified by sex were conducted with spousal GMH score at follow-up (1995-97, T2) as the outcome variable, adjusting for spousal GMH score at baseline (1984-86, T1) and several covariates.
Results: Results showed that male and female spouses whose partners had become somatically ill since T1 had significantly poorer mental health than partners in the reference category, comprising couples healthy at both time points. Further, female spouses of partners who had recovered from illness since T1 had significantly better mental health than controls. Of the somatic conditions, physical disability had the most significant contribution on spousal GMH, for both sexes, in addition to stroke on male spouses' GMH. The effect sizes were small. Some of the loss of spousal mental health seems to be mediated by the ill persons' psychological distress.
Conclusion: The occurrence of partner illness during the follow-up period affect the mental health of spouses negatively, while partner recovery appeared to be associated with improved mental health scores for female spouses. Of the measured conditions, physical disability had the largest impact on spousal distress, but for some conditions the distress of the ill person mediated much of the loss of mental health among spouses.