Psychosocial functioning does not necessarily improve concurrently with depressive symptoms in patients with major depressive disorder (MDD) being treated with electroconvulsive therapy (ECT), according to a new study.
Ching-Hua Lin MD, PhD and colleagues, of the Kaohsiung Municipal Kai-Syan Psychiatric Hospital in Taiwan, studied 130 inpatients (age ≥18) with MDD being treated with ECT to explore whether functional improvement accompanied improvement in depressive symptoms.
Subjects required a 17-item Hamilton Depression Rating Scale (HAM-D17) score of ≥18 at baseline and to meet DSM-IV criteria for MDD. Psychosocial functioning was determined using the Modified Work and Social Adjustment Scale (MWSAS). The HAM-D17 and the MWSAS were administered before ECT, and then 1 to 2 days after every 3 ECT treatments, and after the final treatment.
To compare the degree of change in depressive symptoms and functioning after ECT, the researchers converted HAM-D17 and MWSAS scores to T-score units and used structural equation modeling (SEM) to test the relationships between HAM-D17 and MWSAS.
Patients with a history of psychotic disorders were excluded from the study. Psychotropic medications — particularly antipsychotics, antidepressants, and mood stabilizers — were withdrawn prior to the study, although benzodiazepines were permitted as needed for severe anxiety if administered more than 8 hours prior to ECT treatment.
Of the 116 subjects who completed all treatments, 29.3% were men and 70.7% were women. Patients’ mean age was 26.9 (SD 12.3) and mean age at MDD onset was 38.1 (12.8). Patients who received ECT 3 times weekly experienced significantly higher rates of subjective memory impairments than did patients treated with twice-weekly ECT.
The researchers found that at assessments 2, 3, 4, and 5, the reduction in HAM-D17 T-scores was significantly greater than that in WMSAS T-scores (estimate −11.6, P <0.001), and persisted through assessments 3, 4, and 5 (estimate −16.7, P <0 .001; estimate −16.9, P <0.001; and estimate −16.04, P < 0.001 respectively).
“These results suggest that HAM-D17 scores changed sooner than MWSAS T-scores at assessments 2, 3, 4, and 5. The trajectory of symptom reduction did not parallel that of functional improvement,” the investigators wrote.
The researchers reported that the cross-lagged longitudinal data model analyzed by SEM (c=32.882, P=0.107, TLI = 0.92, CFI = 0.984, RMSEA = 0.057) “satisfied all indices of goodness-of-fit.”
Although the path between MWSAS at assessment 1 and HAM-D17 at assessment 2 was significant (P <0.05), indicating that MWSAS score change at baseline (ie, assessment 1) was significantly associated with subsequent HAM-D17 score change at assessment 2, HAM-D17 changes did not predict subsequent MWSAS change.
The investigators noted that their study was the first to explore the relationships between depressive symptoms and functioning in patients with MDD receiving acute ECT. However, their findings were consistent with previous studies, they stated.
The first finding of the study — ie, that functional improvement lagged behind, rather than paralleled, symptomatic improvement —was consistent with previous reports of depressed patients treated with psychotherapy, pharmacotherapy, or a combination of both. “Functioning may be more difficult to change than depressive symptoms” and “should therefore be regarded as a distinctive domain of therapy,” they hypothesize. They suggest that residual depressive, neurocognitive impairment, or comorbidity may be important factors impacting functional improvement.
The second finding of the study was that “symptom relief did not predict subsequent functional improvement,” suggesting that symptom reduction may not “drive” functional improvement.
The researchers concluded that depressive symptoms and functional impairment are “distinct domains.” They advised that “assessing both depressive symptom severity and functioning repeatedly throughout treatment is an important consideration when determining the efficacy of ECT” and may “provide various and complementary information.”
Lin CH, Yang WC. The relationship between symptom relief and psychosocial functional improvement during acute electroconvulsive therapy for patients with major depressive disorder [published online April 18, 2017]. Int J Neuropsychopharmacol. doi:10.1093/ijnp/pyx022