Retinal thickness and antidepressants

Abstract

Abstract Background Depression is associated with synaptic pruning in the brain. Antidepressants reverse this process. Synaptic pruning can be inferred by measuring retinal thickness with ocular coherence tomography (OCT). With data from UK Biobank, we have done a cross-sectional study comparing retinal thickness in patients on antidepressants. Methods OCT measurements are from UK Biobank category 10016, retinal optical coherence tomography. OCT was performed with the TOPCON 3D OCT 1000 Mk2. Antidepressant medication record is from UK Biobank Data-Field 20003, medications. Information on prolonged depression is from Data-Field 20446, category depression, mental health, online follow up. Question asked: "Have you ever had a time in your life when you felt sad, blue, or depressed for two weeks or more in a row?" We computed mean macular thickness of four regions in each eye: macular thickness at the inner inferior subfield, macular thickness at the inner nasal subfield, macular thickness at the inner superior subfield, and macular thickness at the inner temporal subfield. Results Selective serotonin reuptake inhibitors (SSRIs) and tricyclics were associated with thinner retinas. The Serotonin and norepinephrine reuptake inhibitor SNRI venlafaxine does not affect retinal thickness. Subjects taking venlafaxine had retinal thickness that was not significantly different from subjects not taking antidepressants. Conclusion Patients are most likely to drop out of SSRI therapy due to decreased visual acuity. Our finding that SNRIs do not affect retinal thickness suggests that these dropout patients might do well on SNRIs.