Smoking cessation and 16-year trajectories of functional limitations among Dutch older adults: Results from the Longitudinal Aging Study Amsterdam

Background: This study examined whether smoking cessation in middle age and old age is associated with following a successful trajectory of functional limitations over time in Dutch older adults. Methods: We used 16-year longitudinal data from 645 participants of the Longitudinal Aging Study Amsterdam. Three types of trajectories regarding functional limitations over time were defined: successful (high initial level of functioning and limited decline), late decline (high initial level of functioning and late onset of decline), and early decline (lower initial level of functioning and early onset of decline). Smoking cessation status was self-reported and categorized into: early quitters (stopped in middle age [35-40 years]), late quitters (already smoked in middle age and stopped in old age [≥55 years]), and continued smokers (smoked in middle age and still smoking in old age). Multinomial Logistic Regression Analyses were used to assess the association between smoking cessation and trajectory membership. Results: The sample (55-85 years at baseline) consisted of 20.3% early quitters, 22.9% late quitters, and 56.8% continued smokers. After adjustment for confounders, the model showed that late quitters were less likely to follow an early decline trajectory instead of a successful trajectory compared to continued smokers (odds ratio [OR] = 0.48, 95% confidence interval [CI] = 0.24-0.97). After adjustment for clinically relevant level of depressive symptoms, this association remained substantial but was no longer statistically significant (OR = 0.50, 95% CI = 0.24-1.02). Conclusions: Although not statistically significant in the full model, the observed associations suggest that smoking cessation in old age may have an important impact on daily functioning in old age.