24-Month effect of smoking cessation on cognitive function and brain structure in later life

Abstract

Background: Observational studies investigating the association between smoking, cognitive decline and dementia have produced conflicting results. We completed this trial to determine if smoking cessation decreases the progression of cognitive decline in later life. Methods: We recruited older smokers (n. =229) and never smokers (n. =98) and invited smokers to join a smoking cessation trial. The primary outcome of interest was change in Alzheimer's Disease Assessment Scale cognitive subscale (ADAS-cog) scores over 24. months. Secondary measures included the Logical Memory test and changes in gray matter density. Successful smoking cessation was defined as a minimum of 547 smoking free days d..