Hobby engagement, disability transitions, and life expectancy: a multinational longitudinal study.

Background: Hobby engagement has been identified as a potentially modifiable determinant of healthy ageing, associated with reduced mortality and better cognitive outcomes. However, its role in functional disability transitions and life expectancy across diverse cultural contexts remains insufficiently characterised. In this study, we aimed to examine associations between hobby engagement and functional disability transitions among middle-aged and older adults across Mexico, UK, China, USA, and Europe, and to further quantify the life expectancy implications of hobby engagement across diverse cultural contexts. Methods: We conducted a prospective cohort study using harmonised data from five major longitudinal ageing surveys, encompassing 127 650 participants aged >50 years from 24 countries. Hobby engagement was assessed as binary participation in activities such as volunteering, clubs, reading, or games. Functional disability states were defined as no disability, mild disability, severe disability, and death. Using continuous-time multi-state Markov models, we analysed transitions between states, with life expectancy difference measures calculated at five-year intervals from ages 50-90. Results: Hobby engagement prevalence varied substantially across regions (25.2-83.3%). Hobby participation was associated with a lower risk of transitioning from no disability to mild disability, a higher likelihood of recovery from severe disability to functional independence, and a lower mortality risk from severe disability across the four countries and Europe. These associations translated into differences in life expectancy. At the age of 50 years, functional life expectancy differences ranged from 4.73-5.17 years, and total life expectancy differences ranged from 2.46-4.64 years across the four countries and Europe, with associations between hobby engagement and life expectancy persisting through age 90 (except in China). Life expectancy differences varied by gender, chronic disease status, and geographic location in some countries. Conclusions: Hobby engagement is consistently associated with favourable functional disability transitions and longer life expectancy across diverse cultural contexts, with findings remaining stable in sensitivity analyses, supporting its consideration in healthy ageing strategies.