Abstract
Purpose :
We investigated the association between age and retinal microvasculature parameters as measured by OCTA as well as the effects of diabetes with no retinopathy (DM no DR) or mild diabetic retinopathy (mild NPDR) on these associations in a diverse urban county hospital.
Methods :
In this cross-sectional study, 3x3 mm macular OCTA images were obtained from healthy adults and adults with DM no DR or mild NPDR. Parameters analyzed included foveal avascular zone (FAZ) area and perimeter, vessel density (VD), vessel length density (VLD), and adjusted flow index (AFI) of the superficial (SCP) and deep capillary plexuses (DCP). Using multivariable linear regression models adjusted for covariates of sex, race/ethnicity, signal strength, disease duration, hypertensive status, and HbgA1c, the associations between OCTA parameters and age as stratified by DR status were explored. Interaction terms between age and DR status modeled the effects of DR on the relationship between OCTA parameters and age. P values <0.05 were considered significant after multiple comparison adjustment with Benjamini-Hochberg.
Results :
2026 patients (2026 eyes) were included (48.5% male; mean age: 55.2 years), consisting of those with no diabetes (N=217), DM no DR (N=1499) and mild NPDR (N=310). Overall, both SCP and DCP VD and VLD decreased significantly with age in both the diabetic and healthy groups. FAZ parameters showed a trend of increasing with age in all groups. Younger patients with diabetes started with higher SCP and DCP AFI but experienced a significantly faster rate of decline per year compared to controls, and eventually AFI fell below controls at ages 73.0 and 64.7 years for SCP and DCP respectively. For DCP VD, mild NPDR patients had lower densities compared to controls at younger ages but had a significantly slower rate of decline and eventually overlapped with controls at age 71.9 years.
Conclusions :
There is a reduction of superficial and deep VD and VLD with aging in both controls and those with DM no DR and mild NPDR but the rate of decline is different for these groups especially in patients with clinical signs of retinopathy. Thus, it is important to consider the interaction between age and diabetic microvascular changes which may produce seemingly contradictory changes in OCTA parameters.
This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.