Whether magnetic seizure therapy (MST) is effective and acceptable to treat treatment-resistant depression (TRD).
Why this is important
More than 30% of patients with depression respond poorly to medicine and psychotherapy. We recognise those people as patients with TRD. They suffer from much higher rates of disability and economic burden compared with non-TRD patients.
Electroconvulsive therapy (ECT) is an important treatment for people with TRD. Nevertheless, ECT is often associated with cognitive adverse effects, such as memory loss. Magnetic seizure therapy (MST) is a potential alternative to ECT with fewer cognitive adverse effects. Therefore, it is important to know how well MST works for treating people with TRD.
What we did
In March 2020, we searched randomised controlled trials (RCTs) for studies of MST for treatment-resistant depression. Participants received different treatments at random. This study design provides the most reliable evidence.
Outcomes included how well treatments worked (improvement in symptom severity, quality of life, and social functioning, as well as in numbers of participants conducting suicides, making suicide attempts, or inflicting self-harm) and whether participants experienced adverse effects (cognitive function, number of dropouts, and number of adverse events).
What we found
We included three studies involving 65 participants. These studies compared MST and ECT with up to 12 treatment sessions in six weeks. Existing evidence did not reveal differences in effectiveness or tolerance between MST and ECT.
However, we are not sure how reliable study results are. All findings are based on only a few studies with a small number of participants. Participants knew which treatment they received. Studies were conducted in a different way from their protocols. Some key information was not reported, such as how participants were allocated to different treatments and whether there were participant dropouts from these studies. All studies were conducted by a single research team in Germany and were funded in part by the manufacturer of an MST device.
Evidence regarding effects of MST on patients with TRD is currently insufficient. Our analyses of available data did not reveal clearly different effects between MST and ECT. Our certainty in the evidence is very low. Large, long, well-designed, well-reported trials are needed to further examine the effects of MST.
Evidence regarding effects of MST on patients with TRD is currently insufficient. Our analyses of available data did not reveal clearly different effects between MST and ECT. We are uncertain about these findings because of risk of bias and imprecision of estimates. Large, long, well-designed, and well-reported trials are needed to further examine the effects of MST.
Magnetic seizure therapy (MST) is a potential alternative to electroconvulsive therapy (ECT). Reports to date on use of MST for patients with treatment-resistant depression (TRD) are limited.
To evaluate the effects of MST in comparison with sham-MST, antidepressant, and other forms of electric or magnetic treatment for adults with TRD.
In March 2020, we searched a wide range of international electronic sources for published, unpublished, and ongoing studies. We handsearched the reference lists of all included studies and relevant systematic reviews and conference proceedings of the Annual Meeting of the American College of Neuropsychopharmacology (ACNP), the Annual Scientific Convention and Meeting, and the Annual Meeting of the European College of Neuropsychopharmacology (ECNP) to identify additional studies.
All randomised clinical trials (RCTs) focused on MST for adults with TRD.
Two review authors extracted data independently. For binary outcomes, we calculated risk ratios (RRs) and 95% confidence intervals (CIs). For continuous data, we estimated mean differences (MDs) between groups and 95% CIs. We employed a random-effects model for analyses. We assessed risk of bias for included studies and created a 'Summary of findings' table using the GRADE approach. Our main outcomes of interest were symptom severity, cognitive function, suicide, quality of life, social functioning, dropout for any reason, serious adverse events, and adverse events that led to discontinuation of treatment.
We included three studies (65 participants) comparing MST with ECT. Two studies reported depressive symptoms with the Hamilton Rating Scale for Depression (HAMD). However, in one study, the data were skewed and there was an imbalance in baseline characteristics. Analysis of these two studies showed no clear differences in depressive symptoms between treatment groups (MD 0.71, 95% CI -2.23 to 3.65; 2 studies, 40 participants; very low-certainty evidence). Two studies investigated multiple domains of cognitive function. However most of the outcomes were not measured by validated neuropsychological tests, and many of the data suffered from unbalanced baseline and skewed distribution. Analysis of immediate memory performance measured by the Wechsler Memory Scale showed no clear differences between treatment groups (MD 0.40, 95% CI -4.16 to 4.96; 1 study, 20 participants; very low-certainty evidence). Analysis of delayed memory performance measured by the Wechsler Memory Scale also showed no clear differences between treatment groups (MD 2.57, 95% CI -2.39 to 7.53; 1 study, 20 participants; very low-certainty evidence). Only one study reported quality of life, but the data were skewed and baseline data were unbalanced across groups. Analysis of quality of life showed no clear differences between treatment groups (MD 14.86, 95% CI -42.26 to 71.98; 1 study, 20 participants; very low-certainty evidence). Only one study reported dropout and adverse events that led to discontinuation of treatment. Analysis of reported data showed no clear differences between treatment groups for this outcome (RR 1.38, 95% CI 0.28 to 6.91; 1 study, 25 participants; very low-certainty evidence). Adverse events occurred in only two participants who received ECT (worsening of preexisting coronary heart disease and a cognitive adverse effect). None of the included studies reported outcomes on suicide and social functioning. No RCTs comparing MST with other treatments were identified.