Choroidal vessel density in major depressive disorder using swept-source optical coherence tomography angiography

Background: Previous studies have revealed the retinal structural impairment in major depressive disorder (MDD). The choroid is more affected by systemic changes compared to the retina and provides nutrients to the retina. It is uncertain whether the choroidal structure was damaged in MDD. Therefore, this study aimed to investigate choroidal vessel density (VD) in MDD patients using swept-source optical coherence tomography angiography (SS-OCTA).Methods: This study investigated the choroidal and retinal VD of subjects with SS-OCTA. MDD was identified based on the Diagnostic and International Classification of Diseases, 10th edition (ICD-10). The VD was automatically calculated as the ratio of the pixel areas of the vessels divided by the total area of the regions by the device.Results: Compared with healthy controls (HCs) (n = 45 eyes), the MDD group (n = 66 eyes) demonstrated significantly lower supranasal and temporal choroidal vessel volume (CVV), temporal choroidal vessel volume index (CVI), and supranasal and temporal choroidal stroma volume (CSV) (all p < 0.05). After adjustment for age and sex, we found that temporal CVV (beta = -9.31, p = 0.040) and supranasal (beta = -15.28, p = 0.034) and temporal CSV (beta = -11.82, p = 0.036) were significantly associated with MDD. Both choroidal thickness and retinal VD indicators did not differ significantly between MDD patients and HCs (both p > 0.05).Limitations: Conclusions about progressive changes in choroidal vascular structures during the course of MDD are limited by the our cross-sectional study.Conclusions: We found the choroidal VD in MDD was lower compared with HCs, which suggests that decreased choroidal VD is associated with the MDD.