Early-life risk factors and the development of Alzheimer's disease.
OBJECTIVE
To investigate the association of early-life factors with AD.


BACKGROUND
The early-life environment and its effect on growth and maturation of children and adolescents are linked to many adult chronic diseases (heart disease, stroke, hypertension, and diabetes mellitus), and these effects are also linked to maternal reproduction. AD may have an early-life link. The areas of the brain that show the earliest signs of AD are the same areas of the brain that take the longest to mature during childhood and adolescence. A poor-quality childhood or adolescent environment could prevent the brain from reaching complete levels of maturation. Lower levels of brain maturation may put people at higher risk for AD.


METHODS
In a community-based case-control study (393 cases, 377 controls), we investigated the association of early-life factors and AD. Early-life variables include mother's age at patient's birth, birth order, number of siblings, and area of residence before age 18 years. Patient education level and apolipoprotein E (APOE) genotypes were also included in the analysis.


RESULTS
Area of residence before age 18 years and number of siblings are associated with subsequent development of AD. For each additional child in the family the risk of AD increases by 8% (OR = 1.08, 95% CI = 1.01 to 1.15). More controls compared with cases grew up in the suburbs (OR = 0.45, 95% CI = 0.25 to 0.82). APOE epsilon 4 and the patient's education level did not confound or modify the associations.


CONCLUSIONS
The early-life childhood and adolescent environment is associated with the risk of AD.
Moceri
V M
VM
Department of Epidemiology, University of Washington, Seattle 98195-7236, USA. moceri@u.washington.edu
Kukull
W A
WA
Emanuel
I
I
van Belle
G
G
Larson
E B
EB
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000483:Alleles; D000544:Alzheimer Disease / Q000453:epidemiology* / Q000235:genetics; D053327:Apolipoprotein E4; D001057:Apolipoproteins E / Q000235:genetics; D016022:Case-Control Studies; D002648:Child; D002908:Chronic Disease; D004522:Educational Status; D005260:Female; D005838:Genotype; D006801:Humans; D008297:Male; D008423:Maternal Age; D008875:Middle Aged; D009679:Nuclear Family; D012307:Risk Factors; D012424:Rural Population; D013383:Suburban Population; D014505:Urban Population
D053327:Apolipoprotein E4; D001057:Apolipoproteins E