Low blood pressure and incidence of dementia in a very old sample: dependent on initial cognition.
OBJECTIVE
To examine whether initially low blood pressure is related to the incidence of dementia.


METHODS
A population-based prospective study.


METHODS
The Kungsholmen district of Stockholm, Sweden


METHODS
Three hundred four nondemented subjects aged 75 to 96 years at baseline.


RESULTS
After an average of 3 years, 81 dementia cases were identified (67 with Alzheimer's disease cases). Compared with individuals with baseline systolic pressure of 141 to 179 mm Hg, those with systolic pressure < or = 140 mm Hg had a significantly higher risk of dementia (relative risk (RR) = 1.9, 95% confidence interval (CI), 1.2-3.2) and Alzheimer's disease (RR = 2.2, 95% CI, 1.2-3.8). However, the RR in relation to systolic pressure < or = 140 mm Hg was 1.3 (0.8-2.2) for all dementia and 1.5 (0.8-2.6) for Alzheimer's disease, when the baseline Mini-Mental State Examination (MMSE) score was included in the model as a dichotomous variable (< 24 vs > or = 24). Baseline MMSE < 24 significantly predicted the occurrence of dementia (RR = 6.9; 95% CI, 4.3-11.1). Systolic pressure < or = 140 mm Hg was significantly related to MMSE score < 24 at baseline.


CONCLUSIONS
These data suggest that low blood pressure may be an early correlate of a dementing process although a causative effect cannot be definitely ruled out.
Guo
Z
Z
Department of Clinical Neuroscience and Family Medicine, Huddinge University Hospital, Karolinska Institute, Stockholm, Sweden.
Viitanen
M
M
Winblad
B
B
Fratiglioni
L
L
D000368:Aged; D000369:Aged, 80 and over; D001794:Blood Pressure; D003071:Cognition; D003704:Dementia / Q000175:diagnosis / Q000453:epidemiology* / Q000503:physiopathology; D005260:Female; D006801:Humans; D007022:Hypotension / Q000175:diagnosis / Q000453:epidemiology* / Q000503:physiopathology; D015994:Incidence; D008297:Male; D016016:Proportional Hazards Models; D011897:Random Allocation; D012307:Risk Factors; D013548:Sweden / Q000453:epidemiology; D014505:Urban Population / Q000706:statistics & numerical data