Obesity and vascular risk factors at midlife and the risk of dementia and Alzheimer disease.
BACKGROUND
Vascular risk factors play a role in the development of dementia, including Alzheimer disease (AD). However, little is known about the effect of body mass index and clustering of vascular risk factors on the development of dementia.


OBJECTIVE
To investigate the relation between midlife body mass index and clustering of vascular risk factors and subsequent dementia and AD.


METHODS
Participants of the Cardiovascular Risk Factors, Aging, and Dementia (CAIDE) study were derived from random, population-based samples previously studied in a survey carried out in 1972, 1977, 1982, or 1987. After an average follow-up of 21 years, 1449 individuals (73%) aged 65 to 79 years participated in the reexamination in 1998.


METHODS
Dementia and AD.


RESULTS
Obesity at midlife (body mass index>30 kg/m2) was associated with the risk of dementia and AD even after adjusting for sociodemographic variables (odds ratio [OR], 2.4 [95% confidence interval (CI), 1.2-5.1]). The association was somewhat modified by further adjusting for midlife blood pressure, total cholesterol level, and smoking (OR, 2.1 [95% CI, 1.0-4.6]) and also for apolipoprotein E genotype and history of vascular disorders (OR, 1.9 [95% CI, 0.8-4.6]). Midlife obesity, high total cholesterol level, and high systolic blood pressure were all significant risk factors for dementia with ORs of around 2 for each factor, and they increased the risk additively (OR, 6.2 for the combination).


CONCLUSIONS
Obesity at midlife is associated with an increased risk of dementia and AD later in life. Clustering of vascular risk factors increases the risk in an additive manner. The role of weight reduction for the prevention of dementia needs to be further investigated.
Kivipelto
Miia
M
Aging Research Center, Division of Geriatric Epidemiology, Neurotec, Karolinska Institutet, Stockholm, Sweden. miia.kivipelto@neurotec.ki.se
Ngandu
Tiia
T
Fratiglioni
Laura
L
Viitanen
Matti
M
Kåreholt
Ingemar
I
Winblad
Bengt
B
Helkala
Eeva-Liisa
EL
Tuomilehto
Jaakko
J
Soininen
Hilkka
H
Nissinen
Aulikki
A
D000367:Age Factors; D000368:Aged; D000544:Alzheimer Disease / Q000209:etiology*; D015992:Body Mass Index; D002784:Cholesterol / Q000097:blood; D003704:Dementia / Q000209:etiology*; D005260:Female; D006801:Humans; D006973:Hypertension / Q000150:complications*; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000150:complications*; D012307:Risk Factors
D002784:Cholesterol