Baseline cognitive function does not predict the treatment outcome of electroconvulsive therapy (ECT) in late-life depression.

BACKGROUND: No prior study has investigated whether impairment of specific cognitive functions at baseline may predict the short-term treatment outcome of electroconvulsive therapy (ECT) in elderly non-demented patients with major depression (MD).

METHODS: This longitudinal cohort study included 65 elderly patients with unipolar or bipolar MD, aged 60-85 years, treated with formula-based ECT. Treatment outcome was assessed using the 17-item Hamilton Rating Scale for Depression (HRSD17). Cognitive function at baseline was assessed using nine neuropsychological tests or subtests measuring information processing speed, verbal learning and memory, and aspects of executive function.

RESULTS: A poorer performance on the word reading task of the Color Word Interference Test rendered higher odds of achieving remission during the ECT course (p=0.021). Remission was defined as an HRSD17 score of 7 or less. There were no other significant associations between the treatment outcome of ECT and cognitive performance parameters assessed at baseline.

LIMITATIONS: The limited number of subjects may have reduced the generalizability of the findings. Multiple statistical tests increase the risk for making a type I error.

CONCLUSIONS: How well patients perform on neuropsychological tests at baseline is most likely not a predictor of, or otherwise not significantly associated with the treatment outcome of formula-based ECT in elderly patients with MD.