Abstract
BACKGROUND: To investigate trends over age by comorbidity status for the risk of limitations in individual activities of daily living for community-living older persons. METHODS: A longitudinal population-based study was conducted in 9,319 community-living Dutch persons aged 60 years and older. Self-reported multiple chronic conditions (MCC) and nine instrumental activities of daily livings (IADLs) were assessed in 15 studies of the Dutch National Care for the Elderly Program (TOPICS-MDS). Risks of limitations in IADLs, odds ratios (per 5 years), and rate ratios (per 5 years) were calculated with mixed logistic and negative binomial regression models with age as the underlying timescale, stratified by number of MCC (no, 1-2, ≥ 3 MCC), and corrected for confounders. RESULTS: At inclusion, the number of IADL limitations was highest for the "≥3 MCC" group (2.00 interquartile range [1.00-4.00]) and equal for "no MCC" or "1-2 MCC" (1.00 interquartile range [0.00-2.00]). Trends of individual IADLs depicted a higher risk in IADL limitation with increasing age over 2 years of follow-up, except for handling finances for the "no MCC" group. The longitudinal age effect on IADL limitations varied subject to MCC, being strongest for the "no MCC" group for most IADLs; grooming and telephone use were almost unaltered by age and MCC. CONCLUSION: We observed a decline in IADL functioning with increasing age over 2 years of follow-up in persons with and without MCC. The impact of MCC on IADL decline varied per IADL activity.