The effect of cognition and age on the efficacy of psychotherapy in late-life depression.

BACKGROUND

Cognitive impairment is prevalent in older age and in patients with depression, which may limit the efficacy of psychotherapy for late-life depression (LLD). We analyzed the effect of age and baseline cognition on the efficacy of psychotherapy in LLD.

METHODS

This secondary analysis of a randomized controlled multicenter study included 213 participants (60-92 years) with moderate to severe depression who had received either supportive psychotherapy (SUI) or an LLD-specific cognitive behavioral therapy (LLD-CBT), both of which led to a substantial reduction in depressive symptoms. We examined the influence of age and baseline cognition, assessed with the CERAD-plus neuropsychological battery, on changes in the Geriatric Depression Scale (GDS) at the end of treatment and at 6-month follow-up. Trial registration at ClinicalTrials.gov (NCT03735576) and DRKS (DRKS00013769).

FINDINGS: Baseline cognition was slightly below norms (<1SD), with 15 % of patients meeting criteria for Mild Cognitive Impairment (MCI). GDS change at the end of treatment was not significantly associated with baseline cognition or MCI status, although additional interaction analyses suggest that, in the SUI group, lower baseline cognitive performance was associated with reduced treatment efficacy at follow-up only. Additionally, we found that higher age predicted a smaller reduction in GDS scores both at end-of-treatment and at follow-up in both treatment groups.

INTERPRETATION: Higher age, but not lower cognitive performance, was associated with reduced psychotherapy efficacy. Thus, age-related factors should be considered in psychotherapy.