Cognitive-behavioural therapy does not meaningfully reduce depression in most people with epilepsy: a systematic review of clinically reliable improvement

Psychological treatment is recommended for depression and anxiety in those with epilepsy. This review used standardised criteria to evaluate, for the first time, the clinical relevance of any symptom change these treatments afford patients. Databases were searched until March 2017 for relevant trials in adults. Trial quality was assessed and trial authors asked for individual participants’ pre-treatment and post-treatment distress data. Jacobson’s methodology determined the proportion in the different trial arms demonstrating reliable symptom change on primary and secondary outcome measures and its direction. Search yielded 580 unique articles; only eight eligible trials were identified. Individual participant data for five trials—which included 398 (85%) of the 470 participants randomised by the trials—were received. The treatments evaluated lasted ~7 hours and all incorporated cognitive-behavioural therapy (CBT). Depression was the primary outcome in all; anxiety a secondary outcome in one. On average, post-treatment assessments occurred 12 weeks following randomisation; 2 weeks after treatment had finished. There were some limitations in how trials were conducted, but overall trial quality was ‘good’. Pooled risk difference indicated likelihood of reliable improvement in depression symptoms was significantly higher for those randomised to CBT. The extent of gain was though low—the depressive symptoms of most participants (66.9%) receiving CBT were ‘unchanged’ and 2.7% ‘reliably deteriorated’. Only 30.4% made a ‘reliable improvement. This compares with 10.2% of participants in the control arms who ‘reliably improved’ without intervention. The effect of the treatments on secondary outcome measures, including anxiety, was also low. Existing CBT treatments appear to have limited benefit for depression symptoms in epilepsy. Almost 70% of people with epilepsy do not reliably improve following CBT. Only a limited number of trials have though been conducted in this area and there remains a need for large, well-conducted trials.

Quality ratings for eligible trials providing individual patient data Notes: Each item is scored as yes (1) or no (0). According to guidelines for this instrument, scores for items 2-11 are added to form an overall score: 9-10 indicates a methodologically "excellent" trial, 6-8 "good" quality, 4-5 "fair" and ≤3 "poor" quality.

Eligibility
Inclusion criteria: Stated 'adults' with neurologist confirmed epilepsy diagnosis referred to study with "significant psychosocial problems and inadequate seizure control." Exclusion criteria: "Mental retardation"; psychosis.

Treatment conditions
Compared: CBT to WLC. CBT: Group intervention comprising of 8*120 minute weekly face-to-face sessions, delivered by a clinical psychologist. Receipt of intervention: CBT participants attended an average of 7.4/8 session.
Baseline mean age provided only for sample completing outcome assessment. It was 33.4. Epilepsy: Mean years since diagnosis was reported for total sample as 15.5 and said to be comparable between groups. Distress: Mean BDI score for CBT group 11.13, for the WLC group it was 12.00.

Treatment conditions
Compared: CBT to RT. CBT: Group intervention comprising of 6*120 minute weekly face-to-face sessions delivered by a clinical psychologist. RT: Comprised of group relaxation training, 6*60 minute weekly face-to-face. Training of facilitator not specified.

Receipt of intervention: No information reported
Sample Recruitment: 37 participants enrolled, 18 allocated to CBT, 19 to RT. Demographics: Participants mean age was 67.5 in CBT group and 67.3 in RT group. 10 (56%) of CBT and 9 (47%) of RT participants were female. Epilepsy: Mean years since diagnosis for CBT group was 28.56 compared to 25.89 in RT group. In CBT group, 8 (44.4%) participants had generalized seizures, and 10 (52.6%) partial. In the RT group, 9 (47.3%) had generalized seizures, and 10 (52.6%) partial.
Distress: Mean GDS score for CBT group 12.50, compared to 11.37 for RT group Outcome assessment//s Timing: 8 and ~18 weeks post-randomisation. Retention: 100% of CBT group and 100% of RT group completed both assessments.
Outcome measure/s Primary: Depression, GDS.  Notes: Timing of assessments were: Ciechanowski et al. (2010) follow-up assessment 1 ("post-treatment assessment")= 6 months, follow-up assessment 2= 12 months; follow-up assessment 3= 18 months (reported within Chaytor et al., 2011) ;Gandy et al. (2014) follow-up assessment 1 ("post-treatment assessment")= 9 weeks, follow-up assessment 2= CBT, cognitive behavioural therapy; HADS-A, Hospital Anxiety and Depression Scale -Anxiety subscale; HADS-D, Hospital Anxiety and Depression Scale -Depression subscale; HSCL-20, Hopkins Symptom Checklist-20; NDDI-E, Neurological Disorders Depression Inventory for Epilepsy; WLC ,waitlist control. † The designation of outcome measures as being the primary or secondary outcome measure was taken directly from trial reports, except for Gandy et al.(2014)    When participants without clinical distress at baseline are excluded, difference in proportion of participants showing "reliable improvement" within the eligible trials on primary outcomes of depression post-treatment according to whether treatment was individual face-to-face CBT or of another form