Poster Session: Deep retinal layer microvasculature alterations in first episode and chronic schizophrenia.

Abstract

People with schizophrenia (SZ) demonstrate retinal microvasculature alterations that are similar to those observed in individuals with neurodegenerative disorders. Initial findings indicate that these changes are present in the superficial layer in SZ. This study examined whether changes are also present in the deep retinal layer level (DRL). Twenty-six individuals with SZ (10 with first episode psychosis [FEP]) and 37 healthy controls (HCs; 17 age-matched to FEP group) completed optical coherence tomography angiography scans. Compared to controls, people with SZ demonstrated reduced DRL perfusion density (ps < 0.04) and vessel diameter (ps < 0.01) in both eyes, and, in the left eye only, reduced vessel length and fractal dimension (ps = 0.01). We then tested for an illness progression effect by determining the degree to which the original 4 group means were characterized by a polynomial (linear) trend, using the following contrast coefficients: non-FEP SZ (-2), FEP (0), older controls (0), young controls (2). The hypothesized pattern was observed to a significant or trend level degree for 7 out of 8 variables, with effect sizes ranging from small to large. Findings also indicated that, within the SZ group, reduced DRL perfusion density and vessel length were associated with reductions in (previously reported) superficial layer indices (ps < .001). Overall, findings suggest that alterations in retinal microvasculature are present in both the superficial and DRL in SZ.