Quebec tackles electroconvulsive therapy issue

Electroconvulsive therapy (ECT) may remain the only treatment alternative for some psychiatric patients, a study commissioned by the Quebec government has concluded, but there are still many “uncertainties” surrounding its efficacy and use.

“We believe there is a risk of retrograde amnesia … but we don't know the incidence because the research isn't there,” says Dr. Reiner Banken, the author. The report says the most significant risk is cardiovascular complications, but proper anesthetic technique can help prevent this. The mortality rate is approximately 1 death per 80 000 treatments.

The Use of Electroconvulsive Therapy in Québec (www.aetmis.gouv.qc.ca) calls for ECT patient registries, evidence-based clinical practice guidelines and “particular emphasis” on patient consent because of the inherent risks. Banken says additional education is crucial: “Medical students in psychiatry don't get adequate training, and there is no CME.”

The report says ECT is an effective treatment for patients with severe forms of drug- and therapy-resistant depression. “It's not a cure,” cautions Banken, because it is effective for only 4 to 6 weeks. After that, psychotherapy or drug therapy is required.

The report also presents data on the usefulness of ECT to treat different problems. While there is “excellent evidence” for using it to treat major depression that is drug and psychotherapy resistant, there is little evidence supporting its use to treat schizophrenia.

Banken's report was commissioned after Québec Science reported that the number of ECT treatment sessions in the province had nearly doubled between 1988 and 1995, from 4000 to 7200. The health minister asked the Agence d'évaluation des technologies et des modes d'intervention en santé to assess usage. In his foreword to the report, agency CEO Renaldo Battista described ECT use as “a sensitive issue” but said usage rates in Quebec are similar to international rates. Banken confirmed that practices in Quebec correspond to international standards, but told CMAJ that these “aren't that good.”

Banken found it difficult to gather data. He asked every province and territory how often ECT was used, but got no response. “There's a lack of systematic surveillance of ECT use,” he concludes. The Canadian Institute for Health Information's in-hospital data indicate that about 3000 patients receive ECT per year, including 700 in Quebec.

Banken says the appropriate rate of use is unknown because “there's no epidemiologic evidence.”

ECT has proved controversial since its introduction into psychiatric use in 1938. Proponents claim it is one of the safest and most effective therapies available, while opponents consider it degrading because of the adverse effects, including memory loss. Banken says the report recognizes the differing opinions and “we've made this report as impartial as possible.” — Barbara Sibbald, CMAJ