Blood pressure and white-matter disease progression in a biethnic cohort: Atherosclerosis Risk in Communities (ARIC) study.

BACKGROUND AND PURPOSE

Blood pressure (BP) is a predictor of concurrent and subsequently measured white-matter hyperintensity (WMH), but longitudinal studies of WMH changes and data in black participants are lacking. We hypothesized that WMH progression would be (1) strongly related to BP in blacks and whites and (2) predicted more strongly by earlier (midlife) or cumulative BP measurements than by measures at older ages.

METHODS

Participants were 983 individuals (49% black) from the Atherosclerosis Risk in Communities (ARIC) Study who underwent cerebral magnetic resonance imaging in 1993-1995 and 2004-2006. Associations between BP (measured at each of 5 visits, in addition to a time-averaged cumulative BP) and progression of WMHs were analyzed and compared.

RESULTS

Cumulative systolic BP (SBP) was the strongest BP predictor of WMH progression in adjusted models. Higher cumulative SBP (by 20 mm Hg) was associated with greater progression of WMHs and was similar in blacks (2.5 cm(3), P<0.0001) and whites (2.6 cm(3), P<0.0001). Higher cumulative SBP (per 20 mm Hg) was also associated with being in the top quintile of WMH progression (adjusted odds ratio=2.0; 95% CI, 1.6 to 2.6). Earlier SBP measurements were stronger predictors of WMH progression than were later SBP measurements, but in blacks only.

CONCLUSIONS

In this population-based cohort, cumulative SBP was a stronger predictor of WMH progression than SBP from individual visits, in both blacks and whites. Earlier BPs were stronger predictors than BPs measured at later time points in blacks only.