Pattern electroretinography in individuals with major depression

Aim of the study
Investigation of pattern electroretinography in individuals with major depression (MD).

Material and methods
In 25 untreated individuals with MD (mean age 46.8 years) and in 25 of age- and sex-matched healthy controls (mean age 46.9 years) the following examinations were performed: visual acuity (Snellen), intraocular pressure, biomicroscopy of anterior and posterior segment of eye, macular structure (SD-OCT-Zeiss) and pattern electroretinogram (PERG-ISCEV standards). An analysis of correlation between the parameters of PERG and depression severity (the Hamilton Scale) was performed. To estimate the diagnostic power of the PERG test a receiver operating characteristics (ROC) curve was used. Obtained data were used to analyze the significance level p < 0.05.

Results
In both groups the clinical results and macular structure were normal. In the PERG test in the MD group a significant decrease of amplitudes of P50 (AP50) and N95 (AN95) waves (p < 0.001) was detected. The most frequent abnormality was the reduction of AN95 (32.0%). The Hamilton Scale correlated negatively and significantly with AN95 (p = 0.036). The analysis of ROC curve revealed that in the case of AP50 the cut-off point was 6.75 with sensitivity 0.960 and specificity 0.840. The area under the curve (AUC) was 0.931 (p < 0.001). In the case of AN95, the cut-off point was 9.0, with sensitivity 0.920 and specificity 0.920. The AUC was 0.923 (p < 0.001).

Conclusions
In major depression, a dysfunction of the ganglion cells in the macular region is present with the ability to be registered by PERG recording. The abnormalities in function of the ganglion cells detected in PERG examination have the potential to be an objective marker of MD.