Cognitive disturbance comparison among drug-naïve depressed cases and healthy controls.

Objective: To assess and compare cognitive disturbances among newly diagnosed depressed and healthy control cases on the McNair and Kahn auto-evaluation scale.

Study Design: Comparative, cross-sectional study.

Place And Duration Of Study: Out-patients Department of Psychiatry, Jinnah Postgraduate Medical Centre, Karachi, Pakistan, from February to May, 2007.

Methodology: All consecutive new cases reporting at the out patient department were screened for depressive illness. They were matched with healthy-controls aged between 18-40 years. Clinical assessment was carried out on the basis of detailed history, physical examination, mental state examination by psychiatrists. For diagnostic purpose, application of ICD-10 followed by administration of Scale for Cognitive Difficulties.

Results: Sixty subjects, 30 depressed patients (20 females and 10 males) and 30 healthy-controls (18 females and 12 males) were assessed. The age of cases with depressive disorder ranged 18-38 years. It was found that 63.3% (65% females and 60% males) depressed patients had cognitive difficulties compared to 3.3% of healthy-controls (p < 0.001). Proportions were compared using chi-square test with significance at p < 0.05.

Conclusion: Depression is not merely an emotional (mood) disorder but has an impact on cognition domain as well. Attention/concentration was the most common domain of cognition affected, followed by memory disturbance among the drug-naïve depressed patients.