Late-life body mass index and dementia incidence: nine-year follow-up data from the Kungsholmen Project.
OBJECTIVE
To describe the association between late-life body mass index (BMI) and dementia development with a time perspective and to investigate the effect of weight changes on dementia incidence.


METHODS
Three-, 6-, and 9-year follow-up study.


METHODS
The Kungsholmen Project.


METHODS
One thousand two hundred fifty-five subjects aged 75 and older with baseline BMI data available.


METHODS
Cox-regression models were used to estimate hazard ratios (HRs) for dementia detected at different risk periods in relation to baseline BMI. The association between BMI changes and development of dementia after 3 and 6 years was also analyzed.


RESULTS
Subjects with a BMI of 25.0 kg/m2 or higher had a lower risk of developing dementia than subjects with a BMI of 20.0 to 24.9 (HR=0.75, 95% confidence interval (CI)=0.59-0.96), even when cases occurring only during the last follow-up period (6-9 years after BMI assessment) were included (HR=0.66. 95% CI=0.40-1.07). Severe BMI loss (>10%) was related to a greater risk of dementia, but this association was present only for dementia cases detected in the subsequent 3 years (HR=2.18, 95% CI=1.27-3.74).


CONCLUSIONS
This study does not confirm that being overweight in late life is a risk factor for dementia, although a protective effect for a BMI greater than 25.0 is suggested. In addition, BMI loss is confirmed as a marker of incipient dementia. The findings suggest that, from a clinical perspective, the cognitive profile of elderly persons with unexplained weight loss should be considered and that being moderately overweight at older ages might be indicative of good health status.
Atti
Anna Rita
AR
Aging Research Center, Karolinska Institutet and Stockholm Gerontology Research Center, Stockholm, Sweden. anna.rita.atti@ki.se
Palmer
Katie
K
Volpato
Stefano
S
Winblad
Bengt
B
De Ronchi
Diana
D
Fratiglioni
Laura
L
D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology* / Q000523:psychology; D015992:Body Mass Index; D003704:Dementia / Q000175:diagnosis / Q000453:epidemiology* / Q000209:etiology; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D008297:Male; D009765:Obesity / Q000150:complications / Q000453:epidemiology; D011379:Prognosis; D012189:Retrospective Studies; D012307:Risk Factors; D012737:Sex Factors; D013548:Sweden / Q000453:epidemiology; D013997:Time Factors