#DYK that smoking increases your risk of dementia? Ahead of #NoSmokingDay we’re raising awareness that if you stop smoking it will help protect your brain health and reduce your risk of dementia.

Objective

The aim of this study was to investigate the risk of developing dementia in relation to the duration of smoking cessation, using a nationwide health claims database.

Methodology

This cohort study examined 46,140 men aged 60 years or older, who were part of the Korean National Health Insurance System – National Health Screening Cohort, a population-based national health screening program conducted between 2002 and 2013. Based on changes in smoking habits between the first (2002-2003) and second (2004-2005) health examinations, participants were categorised as continual smokers, short-term quitters (less than 4 years), long-term quitters (4 years or more), and never smokers. Participants were monitored for eight years from January 1, 2006, to assess their risk of developing overall dementia, Alzheimer’s disease, and vascular dementia.

Results

Compared to continual smokers, long-term quitters and never smokers had a reduced risk of overall dementia (hazard ratio [HR]: 0.86; 95% confidence interval [CI]: 0.75–0.99 and HR: 0.81; 95% CI: 0.71–0.91, respectively). Never smokers had a lower risk of Alzheimer’s disease (HR: 0.82; 95% CI: 0.70–0.96) than continual smokers. Lastly, both long-term quitters (HR: 0.68; 95% CI: 0.48–0.96) and never smokers (HR: 0.71; 95% CI: 0.54–0.95) had a reduced risk of vascular dementia compared to continual smokers.

Conclusion

The study findings indicate that smoking is linked to an increased risk of dementia, and prolonged smoking cessation could potentially reduce the risk of developing dementia. Therefore, encouraging smokers to quit is important, particularly for the elderly population who are already at risk of developing dementia.