The effect of alcohol and tobacco consumption, and apolipoprotein E genotype, on the age of onset in Alzheimer's disease.
OBJECTIVE
This study examined the association between a history of heavy alcohol use and smoking, presence of the apolipoprotein-E epsilon 4 allele (APOE epsilon4), and age of disease onset in a community dwelling sample of 685 Alzheimer's disease (AD) patients spanning three ethnic groups.


METHODS
Cross-sectional study of AD patients evaluated at a University-affiliated outpatient memory disorders clinic.


METHODS
A clinic-based cohort of white non-Hispanic (WNH; n = 397), white Hispanic (WH; n = 264), and African-American (AA; n = 24) patients diagnosed with possible or probable AD according to NINCDS-ADRDA diagnostic criteria.


METHODS
The age of onset of AD was obtained from a knowledgeable family member. All patients were assessed for APOE genotype. History of alcohol and tobacco consumption prior to the onset of dementia was obtained via an interview with the patient and the primary caregiver. A history of heavy drinking was defined as >2 drinks per day and a history of heavy smoking was defined as > or =1 pack per day.


RESULTS
Presence of an APOE epsilon4 allele, a history of heavy drinking, or a history of heavy smoking were each associated with an earlier onset of AD by 2-3 years. Patients with all three risk factors were likely to be diagnosed with AD nearly 10 years earlier than those with none of the risk factors.


CONCLUSIONS
The results suggest that APOE epsilon4 and heavy drinking and heavy smoking lower the age of onset for AD in an additive fashion.
Harwood
Dylan G
DG
David Geffen School of Medicine at UCLA, Semel Institute for Neuroscience and Human Behavior, Los Angeles, CA, USA.
Kalechstein
Ari
A
Barker
Warren W
WW
Strauman
Silvia
S
St George-Hyslop
Peter
P
Iglesias
Casandra
C
Loewenstein
David
D
Duara
Ranjan
R
D001741:Black or African American / Q000235:genetics; D017668:Age of Onset; D000368:Aged; D000369:Aged, 80 and over; D000428:Alcohol Drinking / Q000009:adverse effects*; D000483:Alleles; D000544:Alzheimer Disease / Q000208:ethnology / Q000235:genetics*; D000704:Analysis of Variance; D053327:Apolipoprotein E4 / Q000235:genetics*; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D005260:Female; D005787:Gene Frequency; D005838:Genotype; D006630:Hispanic or Latino / Q000235:genetics; D006801:Humans; D008297:Male; D008875:Middle Aged; D012307:Risk Factors; D012907:Smoking / Q000009:adverse effects*; D014481:United States / Q000453:epidemiology; D044465:White People / Q000235:genetics
D053327:Apolipoprotein E4