Abstract
PURPOSE: We aimed to identify prototypical functional aging trajectories of US cancer survivors aged 50 and older, overall and stratified by sociodemographic and health-related characteristics. METHODS: Data were from 2986 survivors of a first incident cancer diagnosis (except non-melanoma skin cancer) after age 50 in the population representative U.S. Health and Retirement Study from 1998-2016. Cancer diagnoses, episodic memory function, and activity of daily living (ADL) limitations were assessed at biennial study interviews. Using time of cancer diagnosis as the baseline, we used group-based trajectory modeling to identify trajectories of memory function and ADL limitations following diagnosis. RESULTS: We identified five memory loss trajectories (high: 8.4%; medium-high: 18.3%; medium-low: 21.5%; low: 25.5%; and, very low: 26.2%), and four ADL limitation trajectories (high/increasing limitations: 18.7%; medium limitations: 18.7%; low limitations: 8.14%; no limitations: 60.0). The high memory loss and high/increasing ADL limitation trajectories were both characterized by older age, being female (52% for memory, 58.9% for ADL), having lower pre-cancer memory scores, and a higher prevalence of pre-cancer comorbidities including stroke (30.9% for memory and 29.7% for ADL), hypertension (64.7% for memory and 69.8 for ADL), and depressive symptoms. In joint analyses, we found that generally those with higher memory were more likely to have fewer ADL limitations and vice versa. CONCLUSION: Older cancer survivors experience heterogeneous trajectories of functional aging that are largely characterized by comorbidities prior to diagnosis. IMPLICATION FOR CANCER SURVIVORS: Results can help identify older cancer survivors at increased risk for accelerated functional decline.