Variability in midlife systolic blood pressure is related to late-life brain white matter lesions: the Honolulu-Asia Aging study.
OBJECTIVE
Although white matter lesions (WMLs) on brain MRI in older persons are common, the mechanisms are unclear. Besides the associations with advanced age and high blood pressure (BP), variability in systolic BP (SBP) and the resulting changes in blood flow to the deep arteries of the brain may be contributing factors.


METHODS
Japanese-American men in Hawaii have participated in a long-term study of cardiovascular disease, including midlife BP measurements at 3 clinical examinations in the period from 1965 to 1974. In the period from 1991 to 1993, dementia status was added to the fourth examination, and a brain MRI was completed in a fifth examination, which was from 1994 to 1996, on a subset of 575 men, who averaged 82 years. WMLs and ventricular atrophy were determined as the upper fifth in a standardized semiquantitative measure. Excess SBP variability was defined as greater than average increases in BP measurements from up to 3 examinations over 6 years. Logistic regression was used for the association of this variability with WMLs and atrophy, controlling for age, apolipoprotein E4 status, dementia diagnosis, and history of stroke.


RESULTS
There were significant (2-fold) increased risks for WMLs among those with moderate and high SBP variability (third and fifth quintiles compared with the lowest quintile). Those in the highest SBP variability category (the fifth quintile) also had significantly more atrophy.


CONCLUSIONS
These SBP variability-MRI relationships suggest that variation in SBP in midlife may be a contributing factor to the development of WMLs and ventricular atrophy in late life.
Havlik
Richard J
RJ
Laboratory of Epidemiology, Demography, and Biometry, Intramural Research Program, National Institute on Aging, National Institutes of Health, Bethesda, MD 20892, USA. havlikr@gw.nia.nih.gov
Foley
Daniel J
DJ
Sayer
Bryan
B
Masaki
Kamal
K
White
Lon
L
Launer
Lenore J
LJ
D000367:Age Factors; D000368:Aged; D001213:Asian; D001284:Atrophy / Q000473:pathology; D001794:Blood Pressure; D001921:Brain / Q000473:pathology; D001927:Brain Diseases / Q000208:ethnology / Q000209:etiology* / Q000473:pathology*; D002552:Cerebral Ventricles / Q000473:pathology; D015331:Cohort Studies; D003704:Dementia / Q000175:diagnosis; D014644:Genetic Variation; D006254:Hawaii / Q000453:epidemiology; D006801:Humans; D007564:Japan / Q000208:ethnology; D008137:Longitudinal Studies; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D013599:Systole