Noninvasive brain stimulation plus psychosocial intervention eases depression

Noninvasive brain stimulation (NIBS) plus psychosocial intervention is effective in alleviating moderate to severe depression, but not minimal to mild depression, according to results of a meta-analysis.

“Around 10–30 percent of people with depression experience treatment-resistant depression during pharmacotherapy. Given potential limitations of pharmacotherapy for some patients, more treatment options need to be considered,” said the researchers. “This review investigates the efficacy of NIBS plus psychosocial intervention on depressive symptoms.” [BMC Psychiatry 2022;doi:10.1186/s12888-022-03843-0]

The researchers systemically searched five online databases for randomized controlled trials (RCTs) and non-RCTs evaluating the efficacy of NIBS (transcranial direct current stimulation [tDCS] or repetitive transcranial magnetic stimulation [rTMS]) plus psychosocial intervention (ie, cognitive behavioural therapy [CBT], aerobic exercise, etc) vs control intervention in adults with depressive symptoms. The search yielded 8,593 articles, of which 17 studies were included in the meta-analysis.

The total study population comprised 660 adults with depressive symptoms (minimal to mild depression, 29.41 percent; moderate to severe depression, 70.59 percent), among whom 312 were assigned to intervention groups and 348 to control groups (ie, sham NIBS plus psychosocial intervention, NIBS alone, or psychosocial intervention alone).

Results of the meta-analysis showed that NIBS plus psychosocial therapy resulted in a notable improvement in moderate to severe depression (standardized mean difference [SMD], -0.46; 95 percent confidence interval [CI], -0.90 to -0.02; I²=73 percent; p<0.01), but no significant improvement in minimal to mild depression (SMD, -0.12; 95 percent CI, -0.42–0.18; I²=0 percent; p=0.63).

“Compared with NIBS alone, the combination treatment had a significant and large effect of 0.84 [SMD, -0.84; 95 percent CI, -1.25 to -0.42, I²=0 percent; p=0.93], suggesting that the combined intervention is a promising approach to maximize the benefits to be gained from NIBS alone,” reported the researchers. “The combined intervention could be suggested to individuals with high-severity depression or difficult-to-treat depression, or groups who fail to benefit adequately from current standard clinical therapies.”

However, NIBS plus psychosocial intervention was not significantly different from the combination of sham NIBS and psychosocial intervention (SMD, -0.12, 95 percent CI, -0.31–0.07; I²=0 percent; p=0.60). “This is in line with the high rates of placebo effects found in previous systematic reviews for depression. In fact, several meta-analyses have already demonstrated that the placebo effect plays an important role in both tDCS and rTMS trials,” the researchers explained.

Although a recent scoping review showed that NIBS combined with CBT was significantly associated with changes in depressive symptoms, the current meta-analysis showed that NIBS plus psychosocial intervention had no specific enhancing effects on depressive symptoms vs psychosocial intervention alone (SMD, -0.97, 95 percent CI, -2.38–0.38; I²=72 percent; p=0.01).

“With the limited number of studies with each type of psychosocial intervention, it is difficult to evaluate whether NIBS plus a specific type of psychosocial intervention is more effective than NIBS plus others,” commented the researchers. “Therefore, exploring the effectiveness of some specific psychosocial interventions in combination with NIBS for the treatment of depression is the priority suggested for future research.