Age-dependency in mortality of family caregivers : a nationwide register-based study

Background: Evidence on family caregivers' health is conflicting. Aim: To investigate all-cause and cause-specific mortality in Finnish family caregivers providing high-intensity care and to assess whether age modifies the association between family caregiver status and mortality using data from multiple national registers. Methods: The data include all individuals, who received family caregiver's allowance in Finland in 2012 (n = 42,256, mean age 67 years, 71% women) and a control population matched for age, sex, and municipality of residence (n = 83,618). Information on dates and causes of death between 2012 and 2017 were obtained from the Finnish Causes of Death Register. Results: Family caregivers had lower all-cause mortality than the controls over the follow-up (8.1 vs. 11.6%) both among women (socioeconomic status adjusted hazard ratio [HR]: 0.64, 95% CI 0.61-0.68) and men (adjusted HR: 0.73, 95% CI 0.70-0.77). When modelling all-cause mortality as a function of age, younger caregivers had only slightly lower or equal mortality to their controls, but older caregivers had markedly lower mortality than their controls, up to more than 10% lower. Caregivers had a lower mortality rate for all the causes of death studied, namely cardiovascular, cancer, neurological, external, respiratory, gastrointestinal and dementia. The lowest risk was for dementia (subhazard ratio = 0.29, 95% CI 0.25-0.34). Conclusions: Older family caregivers had lower mortality than the age-matched general population while mortality did not differ according to caregiver status in young adulthood. This age-dependent advantage in mortality is likely to reflect the selection of healthier individuals into the family caregiver role.