Objective: The objective of this study was to identify and describe long-term trajectories of bothersome pain and activity-limiting pain in a population-based sample of older adults.
Materials and methods: We conducted a retrospective cohort study of 6783 community-dwelling participants using 6 years of longitudinal data from the National Health and Aging Trends Study (NHATS). NHATS is a cohort of older adults that is representative of Medicare Beneficiaries aged 65 years and older. NHATS data collection began in 2011, and demographic and health data are collected annually through in-person interviews. Participants were asked if they had bothersome pain and activity-limiting pain in the past month. We used group-based trajectory modeling to identify longitudinal patterns of bothersome pain and activity-limiting pain over 6 years. We used weighted, multinomial logistic regression to examine associations with each trajectory.
Results: The cohort was 57% female, 68% white, and 58% were 75 years and older. Four trajectories were identified for the probability of bothersome pain: persistently high (n=1901, 35%), increasing (n=898, 17%), decreasing (n=917, 17%), and low (n=1735, 32%). Similar trajectories were identified for activity-limiting pain: persistently high (n=721, 13%), increasing (n=812, 15%), decreasing (n=677, 12%), and low (n=3241, 60%). The persistently high bothersome and activity-limiting pain groups had worse health characteristics, were more likely to have fallen in the past year, and had slower gait speed and worse physical capacity compared with the low groups.
Discussion: Approximately one half of older adults had a high or increasing probability of long-term bothersome pain, and over one quarter had a high or increasing probability of long-term activity-limiting pain.