Objective: To study cognitive ability in psychiatric inpatients before and after receiving electroconvulsive therapy.

Materials and Methods: The study was a prospective observational cohort. The authors administered Mini-Mental State Examination, Thai version [MMSE-Thai 2002] with patients, who treated with non-maintenance electroconvulsive therapy in the inpatient psychiatric unit, Siriraj Hospital, before ECT, and at 0 to 3 days, 2-week and 2-month after ECT. The data were analyzed by descriptive statistical analysis and one-way repeated measures ANOVA.

Results: 29 subjects participated in the present study. The intention-to-threat analysis showed a statistically significant difference in MMSE scores before ECT and at 0 to 3 days, 2-week, and 2-month after ECT. There was cognitive function decline at 0 to 3 days after treatment but improved at 2-week, and 2-month after ECT. There were significant differences in attention-calculation and recall of cognitive function domains.

Conclusion: The difference of MMSE showed declination in cognitive function in 0 to 3 days after ECT. However, the cognitive function improved significantly at 2-weeks and 2-months after ECT.

Keywords: Electroconvulsive therapy, Cognitive effect, MMSE