Mid-to Late-Life Time-Averaged Cumulative Blood Pressure and Late-Life Retinal Microvasculature: The ARIC Study

Abstract

BACKGROUND: The associations of time-averagedcumulative blood pressure (BP) from midlife to late life with microvasculatureexpressed as retinal vessel diameters is not well studied. The aim of this study was to evaluate the association of cumulativesystolic BP and diastolic BP (DBP) with retinal vessel calibers, focusing on race differences.METHODS AND RESULTS: The analysis included 1818 adults from the ARIC (Atherosclerosis Risk in Communities) study attendingthe fifth visit (2011–2013;age 77±5 years, 17.1% Black participants). Time-averagedcumulative BPs were calculatedas the sum of averaged BPs from adjacent consecutive visits (visits 1–5)indexed to total observation time (24±1 years).Summarized estimates for central retinal arteriolar equivalent and central retinal venular equivalent at the fifth visit representaverage retinal vessel diameters. The arteriole:venule ratio was calculated. We tested for effect modification by race. Resultsfrom multiple linear regression models suggested that higher time-averagedcumulative DBP (β [95% CI] per 1-SDincrease:−1.78 [−2.53, −1.02], P<0.001 and −0.005 [−0.009, −0.002], P=0.004, respectively) but not systolic BP (−0.52 [−1.30, 0.26],P=0.189 and 0.001 [−0.002, 0.005], P=0.485, respectively) was associated with smaller central retinal arteriolar equivalentand arteriole:venule ratio. The association between time-averagedcumulative DBP and arteriole:venule ratio was strongestin White participants (interaction P=0.007). The association of cumulative systolic BP and DBP with central retinal venularequivalent was strongest in Black participants (interaction P=0.015 and 0.011, respectively).CONCLUSIONS: Exposure to higher BP levels, particularly DBP, from midlife to late life is associated with narrower retinal vesseldiameters in late life. Furthermore, race moderated the association of cumulative BP exposure with retinal microvasculature.