Aging affects the retrobulbar circulation differently in women and men

Background: While aging clearly has protean biological effects on every org an system, the differential effects of aging in women and men in the retrob ulbar vasculature, to our knowledge, have never been investigated. Because glaucoma and age-related macular degeneration are closely linked to advance d age, we performed a cross-sectional study using color Doppler imaging of 4 retrobulbar vessels in both healthy women and men. Objective: To define the influence of aging per se on ocular hemodynamics. Methods: Women (n=73) and men (n=55), aged from 20 to 90 years, free of ocu lar and systemic disease, and with normal intraocular pressure, were recrui ted for this study. Postmenopausal women who were not receiving estrogen re placement therapy were also recruited. Studies involved color Doppler imagi ng analysis of the ophthalmic, central retinal, and nasal and temporal post erior ciliary arteries. Ophthalmic arterial peak systolic and end-diastolic velocities and a Pourcelot resistance index were determined for each vesse l. Results: In both sexes, ophthalmic arterial end-diastolic velocity decrease d and the Pourcelot resistance index rose with advancing age teach P<.001); peak systolic velocity in the ophthalmic vessel was age-independent. In co ntrast, central retinal arterial Row velocities were unaffected by age in b oth sexes. In the posterior ciliary arteries, in men, flow velocities and t he Pourcelot resistance index were independent of age. However, in women, e nd-diastolic velocity decreased with age in both the nasal and temporal pos terior ciliary vessel teach P<.05); peak systolic velocity was constant; th e Pourcelot resistance index in each ciliary artery rose with advancing age teach P<.05). Conclusions In healthy women and men, aging-induced changes in retrobulbar hemodynamics are comparable to alterations seen in patients with glaucoma o r age-related macular degeneration, suggesting that vascular changes with s enescence may contribute to increased risk for these diseases in older age.