Association between changes in the retina with major depressive disorder and sleep quality

Major depressive disorder (MDD) is linked to degenerative and inflammatory processes in the brain. The retina, as well as the brain, originates from the ectoderm. The changes in the retina that occur in concert with MDD and sleep quality are not very clear. This study aimed to detect changes in the retinal nerve fibre layer (RNFL) and macular thickness in Chinese patients in correlation with MDD and sleep quality.

Thirty-six MDD patients and 187 age- and sex-matched healthy controls were enrolled in this study. All subjects were scanned by spectral-domain optical coherence tomography (OCT) and completed the Stroop Colour-Word Test (SCWT), Pittsburgh Sleep Quality Index, and Patient Health Questionnaire-9.

The RNFL and macular thickness were significantly thinner and disc-area enlargement of the right eye and cup-volume enlargement of both eyes were present in MDD patients. Linear regression analysis revealed that the RNFL and macular thickness in patients with MDD were correlated with sleep quality and the severity of depression. SCWT scores were higher following expansion of the cup volume of the right eye (all p < 0.01) and in correlation with larger disc areas.

Serious degrees of depression and insomnia in MDD patients may reflect obvious atrophy of the inner and outer rings of the right macula and enlargement of the optic disc in both eyes. These retinal structural changes might influence the visual cognition of patients with MDD.