Association of smoking and alcohol drinking with dementia risk among elderly men in China.

BACKGROUND

Previous studies relating smoking and alcohol drinking with the incidence of dementia have been inconsistent.

OBJECTIVES

We assessed whether smoking and alcohol drinking was associated with the risk of dementia, including Alzheimer disease (AD) and vascular dementia (VaD) after seven years of follow-up.

DESIGN

We prospectively analysed the incidence of dementia from 2004 to 2011 among 2959 elderly men, according to their smoking and alcohol drinking status.

SETTING

six neighbourhoods from three districts mentioned in Chongqing city.

PARTICIPANTS

A total of 3170 men were followed up annually for 7 years.

MEASUREMENTS: Cox proportional hazards models were established to evaluate the association between smoking, alcohol drinking and the risk of dementia.

RESULTS

The incidences of AD and VaD were higher respectively in current smoking than never smoking, daily drinking than never drinking over 7 years of follow-up (p<0.01). After adjusting for age and other potential confounders, current smoking was associated with increased risk of AD (HR= 2.14, 95% CI 1.20-4.46) and VaD (HR= 3.28, 95% CI 1.14-4.52), meanwhile, daily drinking was related to increased risk of AD (HR= 2.25, 95% CI 1.43-3.97) and VaD (HR= 3.42, 95% CI 1.18-4.51). In addition, co-smoking and drinking were related to with a significantly higher risk of AD and VaD than non-smoking and drinking (HR= 3.03, 95% CI 1.65-4.19) and VaD (HR= 3.96, 95% CI 1.64-4.71). Moreover, co-smoking and drinking had higher risk of AD and VaD compared with current smoking and daily drinking.

CONCLUSIONS

Current smoking and daily drinking were found to be significantly associated with dementia in elderly men.