Life-course patterns of chronic somatic conditions and inequalities in later-life sensory health: a social sequence analysis

Knowledge about the association between chronic somatic conditions and sensory impairment (SI) is largely based on cross-sectional studies, with limited evidence from a life course perspective and longitudinal approaches. To address this gap, this study examines the association between patterns of chronic somatic conditions from early to middle adulthood and the incidence of later-life SI among Chinese older adults. Data were drawn from the China Health and Retirement Longitudinal Study implemented during 2011–2018. Sequence analysis was used to group participants based on their chronic somatic conditions during the ages of 18 to 59. The Cox proportional hazard models were used to estimate associations between patterns of chronic somatic conditions and incident SI. Among 3584 participants aged 60 years and older, three distinct patterns of chronic somatic conditions were identified: (I) “long-term health”, (II) “later fast transition to morbidity and multimorbidity”, (III) “early-onset morbidity with slow transition to multimorbidity”. Compared with older adults with pattern I, those with pattern II showed an increased risk of later-life incident any sensory impairment (ASI) [hazard ratio (HR) = 1.35, 95% confidence interval (CI): 1.18–1.55)], vision impairment (VI) (1.51, 1.26–1.81), hearing impairment (HI) (1.28, 1.09–1.50), and dual sensory impairment (DSI) (1.51, 1.17–1.95). Those with pattern III showed an increased risk of later-life incident ASI (1.34, 1.13–1.57), VI (1.36, 1.08–1.71), and HI (1.29, 1.06–1.56). Stratified analyses suggested partially sex and urban-rural differences: associations between Pattern II and higher risk of DSI were significant only in females and rural residents, whereas associations between Pattern III and higher risks of single SI were significant only in males and rural residents. These results provide a new methodological approach to studying multimorbidity from a life-course perspective and underscore the importance of early diagnosis and interventions to promote sensory health in aging populations.