Comparative assessment of cognitive impairment in psychiatric disorders using Addenbrooke’s Cognitive Assessment-III and PGI-brain dysfunction inventory

Background: Cognitive impairment is a core feature of psychiatric disorders, yet its detection varies depending on the assessment tool used. Aim: To compare the Addenbrooke’s Cognitive Assessment-III (ACE-III) and PGI-Brain Dysfunction Inventory (PGI-BBD) in Indian psychiatric patients. Materials and Methods: One hundred adults with schizophrenia, major depressive disorder, bipolar disorder, anxiety disorder, or obsessive-compulsive disorder were evaluated with ACE-III and PGI-BBD at baseline, 1 month, and 3 months. Sociodemographic and clinical correlates were analyzed by Chi square, paired t-tests, and the Cohen kappa correlation. Results: At baseline, 80 (80%) were impaired on ACE-III and 84 (84%) on PGI-BBD, with substantial agreement (κ =0.70). Impairment rates were highest in schizophrenia and major depressive disorder. Both tools showed significant improvement over 3 months (ACE-III: 39.4 ± 16.1 to 67.7 ± 14.8; PGI-BBD: 39.5 ± 13.2 to 9.3 ± 6.8; P < 0.001). Age, male gender, low socioeconomic status, rural location, diabetes, acute onset psychiatric symptoms, substance use, and positive psychiatric past and family history were all significantly correlated with disability. The diagnosis itself was not an important predictor, which supports a transdiagnostic pattern. Conclusion: ACE-III and PGI-BBD provide comparable and robust assessments of cognitive impairment in the Indian Psychiatric population. Both tools are responsive to cognitive change and are strongly influenced by sociodemographic and clinical factors. The routine use of both tools for complex cognitive assessments and monitoring in psychiatric practice is recommended.