A comparative study of retinal layer changes among patients with schizophrenia and healthy controls.

Aim: This study aimed to evaluate the retinal nerve fibre layer changes among different group of patients with schizophrenia and compare it with healthy controls by using swept-source optical coherence tomography.

Methodology: Patients with first-episode schizophrenia (n = 21) in remission (n = 35) or with treatment-resistant schizophrenia (TRS) (n = 35) and 36 healthy controls were evaluated for retinal thickness.

Results: Patients with psychotic illnesses had significantly lower sub-foveal choroidal thickness (effect size 0.84-0.86), when compared to the healthy controls. When patients with first-episode schizophrenia were compared with patients with TRS, TRS patients had significant lower sub-foveal choroidal thickness (left eye) when the various confounders (such as age, gender, duration of treatment, smoking, current medications, body mass index, waist circumference, blood pressure, fasting glucose, HbA1c, presence or absence of metabolic syndrome) were taken into account. When the patients with TRS were compared with healthy controls, initially significant differences were observed for the macular volume (left and right) and the ganglion cell thickness (right eye) but these differences disappeared after controlling for the various covariates.

Conclusions: Compared to healthy controls, patients with schizophrenia, psychotic illnesses have thinning of the retina, especially in the sub-foveal choroidal thickness.