Retinal Vascular Caliber: 6 to 12 Months and 15 to 25 Years Following Hypertensive Pregnancy.

BACKGROUND: Women display retinal vessel caliber abnormalities after hypertensive pregnancy, but whether these predate or reflect vascular aging is unknown. METHODS: Retinal imaging was performed in 2 cohorts: 196 women at 6 to 12 months postpartum (167 hypertensive, 29 normotensive), and 105 women at 15 to 25 years postpartum (64 hypertensive, 41 normotensive), using identical imaging/analysis protocols (Imedos Health, GmbH). Central retinal arteriolar and venular equivalents were calculated, corrected for mean arterial pressure at the time of imaging, and compared across hypertensive and normotensive pregnancy groups using multivariable linear regression models adjusted for body mass index and time postpartum. Z tests were used to compare effect sizes across time points. RESULTS: At both time points, corrected central retinal arteriolar and venular equivalents were lower after hypertensive pregnancies compared with normotensive pregnancies (P<0.001). Between-group differences were larger at 6 to 12 months than 15 to 25 years postpartum for both arteriolar (β=-0.53 versus -0.15; Z=-4.19; P<0.001) and venular calibers (β=-0.50 versus β=-0.18, Z=-3.83; P<0.001), consistent with age-related reductions after normotensive pregnancy. Arteriovenous ratio was significantly different at 6 to 12 months postpartum (P<0.001), but not at 15 to 25 years postpartum. Differences were not explained by blood pressure at the time of imaging, but 6 to 12 months postpartum, related to early pregnancy blood pressure (β=0.01; P<0.001). CONCLUSIONS: Hypertensive pregnancy is associated with retinal vessel changes up to 25 years postpartum that predate age-related reductions and are associated with early pregnancy blood pressure. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT04273854 and NCT05434195.