my personal edition > alzheimer's > news


  E-Mail this DGDispatch to a colleague

DGDispatch

Smoking Significantly Increases Risk of Alzheimer's Disease Among Those Who Have No Genetic Predisposition: Presented at IADRD

By Peggy Peck
Special to DG News

STOCKHOLM, SWEDEN -- July 25, 2002 -- In a case-control study, a history of cigarette smoking doubled the risk of developing Alzheimer's disease among individuals who were not apolipoprotein E (ApoE) carriers but did not influence risk among ApoE genotype individuals.

The findings were reported here July 23 at the 8^th International Conference on Alzheimer's Disease and Related Disorders.

Sara M. Debanne, PhD, of Case Western Reserve University, Cleveland, Ohio, United States, said these findings do not confirm those of earlier studies that suggested a protective effect for smoking on risk of Alzheimer's disease (AD).

Dr. Debanne and colleagues compared smoking effects in 223 AD patients to 396 controls. Data were collected on smoking history during subjects' teenage years, 20s, 40s, and 60s based on surrogate responses for the AD patients and self-responses for controls. Previous research has shown that this design does not introduce recall bias.

Analysis of the full dataset compared ever smokers to never smokers using logistic regression to adjust for birth year, gender, and years of education.

There was no significant statistical association between cigarette smoking and AD among the study cohort. The adjusted odds ratio (OR) for AD in ever smokers was 1.005 (95 percent confidence interval [CI] 0.71- 1.41). Similar results were observed when smoking was analysed in terms of lifetime pack-years (OR 0.996; 95 percent CI 0.98 - 1.01) and across age periods. Inclusion of dietary intake of fat and antioxidants did not change the initial findings.

However, in a secondary analysis of subjects with APOE genotype information (135 AD patients and 278 controls), a statistically significant interaction was found between the APOE-e4 allele presence and smoking.

Among non-carriers of the APOE-e4 allele, there was a significant positive association between AD and smoking (OR 2.16; 95 percent CI 1.03 - 4.52). There was no association between smoking and AD among the carriers of the APOE-e4 allele (OR 0.85; 95 percent CI 0.38 - 1.90).

E-Mail this DGDispatch to a colleague

To print, use this version