ECT Does Not Appear to Increase Risk of Dementia

Electroconvulsive therapy (ECT) does not appear to increase long-term dementia risk in patients, according to a study published online this week in Lancet Psychiatry.

“The findings from this study support the continued use of ECT in patients with severe episodes of mood disorders, including those who are elderly,” wrote Merete Osler, D.Msc., of the Center for Clinical Research and Prevention at the Bispebjerg and Frederiksberg Hospitals in Denmark and colleagues.

ECT is considered a highly effective treatment for severe episodes of mood disorder, particularly major depression, the authors noted. Temporary memory loss is a common side effect, especially with bilateral lead placement and increasing number of treatments. Although such memory loss tends to resolve within weeks, few studies have examined whether patients who receive ECT have a greater risk of long-term adverse cognitive outcomes.

For the study, researchers identified about 168,000 patients aged 10 or older in the Danish National Patient Registry who were hospitalized with a first-time diagnosis of affective disorder from 2005 through 2015. Of these patients, nearly 6,000 (3.5%) underwent at least one ECT during the median 5-year follow-up, with the percentage highest among middle-aged patients. ECT was most common in those with severe depression, comorbid schizophrenia, or in those who used antidepressants or antipsychotic medication.

Of patients who underwent ECT, 3.6% developed dementia. Of some 162,000 patients not treated with ECT, 3.1% developed dementia. Researchers found that after adjusting for the potential effect of patient selection or competing mortality, ECT was not associated with risk of dementia.

In patients younger than 69 years old, ECT was not associated with an increased risk of dementia, compared with age-matched patients who were not given ECT. In patients aged 70 years and older, ECT was associated with a decreased rate of dementia. Furthermore, the risk of developing dementia was lower for patients aged 70 and older who had more than ten sessions of ECT.

“The potential adverse effects of ECT on cognitive function might have fueled the fear of dementia in patients and clinicians, and for that reason they might hesitate to choose ECT as a treatment,” the authors wrote. “The findings from this study show that notwithstanding other possible adverse long-term cognitive effects, ECT did not increase the risk of dementia, and support the continued use of ECT in patients with severe episodes of mood disorders, including those who are elderly.”

Reprinted from http://alert.psychnews.org.
For more information, see the Psychiatric News article “High-Dose, Unilateral ECT Found as Effective as Bilateral ECT.”