Smoking, alcohol and tea drinking on Alzheimer's disease

Objectives: To investigate the risk of Alzheimer's disease (AD) associated with smoking, tea-drinking and alcohol-drinking. Methods: We conducted a population based, m: n matched case-control study on 402 AD patients, and 384 controls matched for age, sex and education. Univariate and multivariate analysis was conducted using conditional Logistic model. Cross analysis was conducted between smoking and vascular events. Results: In multivariate analysis, the OR (odds ratio) was 0. 757 for individuals over 50 years old regular tea drinking 1 -3 times per month compared with those less than once per month (P =0. 0001). And the OR for AD decreased as the frequency of tea-drinking was increased. The OR was 0.4338 for those who drink tea almost everyday. Compared with those who didn't smoke over 50 years old, the OR was 0. 769 for 0.1 ≃ 1-9.9 pack-year smokers(P = 0. 0602). While the OR for those who smoked over 10 pack-year was O. 5914 . There were negative cross effects between smoking and vascular events. There was no relation between alcohol-drinking and AD. Conclusion: This preliminary case-control study suggests that the regular tea-drinking may be the protective factors of AD. Smoking might reduce the risk of AD by itself and increase the risk of AD through the effect of vascular events. There should be dose-response association between regular tea-drinking or smoking and AD. The study might also benefit to the therapy and prevention of AD.