Chronic multimorbidity impairs role functioning in middle-aged and older individuals mostly when non-partnered or living alone

Background Due to the aging of the population, society includes a growing proportion of older individuals prone to chronic morbidity. This study aimed to investigate the adverse effects of single and multiple chronic morbidity on psychosocial health and whether these effects are more pronounced in individuals who are non-partnered or living alone. Materials and methods Baseline data from the 'Lifelines Cohort Study' collected between 2006 and 2013 in the Netherlands were used. Individuals aged 50+ (n = 25,214) were categorized according to their health status (healthy, single chronic morbidity, multiple chronic morbidity), relationship status (partnered, non-partnered), and living arrangement (living with someone, living alone). Analyses of covariance (ANCOVA) were performed to study the main- and the interaction-effects on mental health and role functioning as assessed with the RAND-36. Results Irrespective of having chronic morbidity, having a partner was associated with better mental health when partners shared a home. Individuals with single and especially multiple chronic morbidity had impaired role functioning. Having a partner mitigated the adverse effects of multimorbidity on role functioning, but only in individuals who shared a home with their partner. Non-partnered individuals with multimorbidity and those not sharing a home with their partner demonstrated impaired role functioning. Conclusions The results demonstrate that multimorbidity negatively affects role functioning, but not the mental health, of middle-aged and older individuals. Sharing a home with a partner can mitigate these adverse effects, while other combinations of relationship status and living arrangement do not. Offering intervention to those individuals most vulnerable to impaired functioning may relieve some of the increasing pressure on the health care system. An individual's relationship status along with one's living arrangement could foster the identification of a target group for such interventions attempting to sustain physical functioning or to adapt daily goals.