Electroconvulsive Therapy - Adverse Effects - Effects On Brain Structure

Effects On Brain Structure

Considerable controversy exists over the effects of ECT on brain tissue, although a number of mental health associations — including the American Psychiatric Association — have concluded that there is no evidence that ECT causes structural brain damage. A 1999 report by the United States Surgeon General states, "The fears that ECT causes gross structural brain pathology have not been supported by decades of methodologically sound research in both humans and animals". However, not all experts agree that ECT does not cause brain damage, and two studies have been published since 2007 finding that at least some forms of ECT may result in widespread, persisting, generalized cognitive dysfunction, which might support claims that ECT causes brain damage.

Psychiatrist, Peter Breggin has published books and journalistic reviews of the literature purporting to show that ECT routinely causes brain damage as evidenced by a considerable list of studies in humans and animals. In particular, Breggin asserts that animal and human autopsy studies have shown that ECT routinely causes 'widespread pinpoint hemorrhages and scattered cell death.' According to Breggin, the 1990 APA task force report on ECT ignored much of the scientific literature pointing out the negative effects of electroshock therapy. For example, in 1952 Hans Hartelius conducted and published an animal study on cats entitled Cerebral Changes Following Electrically Induced Convulsions in which a double-blind microscopic pathology examination showed that it was possible to distinguish the 8 shocked animals from the 8 non-shocked animals with remarkable accuracy based on statistically significant structural changes to the brain, including vessel wall changes, gliosis, and nerve cell changes. Based on the detection of shadow cells and neuronophagia, Hartelius determined that there was irreversible damage to neurons associated with electroshock.

Proponents argue that the addition of hyperoxygenation and refinement in technique in the last thirty years has made ECT safe, and a majority of published reviews in recent decades have reflected this position. In a 2004 study designed to evaluate whether modern ECT techniques lead to identifiable brain damage, twelve monkeys underwent daily electroshock for six weeks under conditions meant to simulate human ECT; the animals were then sacrificed and their brains were compared to monkeys undergoing anesthesia alone. According to the researchers, "None of the ECT-treated monkeys showed pathological findings."

There are recent animal studies that have documented significant brain damage after an electroshock series. For example, in 2005, Russian researchers published a study entitled, Electroconvulsive Shock Induces Neuron Death in the Mouse Hippocampus: Correlation of Neurodegeneration with Convulsive Activity. In this study, the researchers found that after an electroshock series, there was a significant loss of neurons in parts of the brain and particularly in defined parts of the hippocampus where up to 10% of neurons were killed. The researchers conclude that "the main cause of neuron death is convulsions evoked by electric shocks." In 2008, Portuguese researchers conducted a rat study aimed at answering the question of whether an electroshock series causes structural changes in vulnerable parts of the brain. According to the authors, "This study answers positively the question of whether repeated administration of ECS seizures can cause brain lesions. Our data are consistent with findings from other animal models and from human studies in showing that neurons located in the entorhinal cortex and in the hilus of the dentate gyrus are particularly vulnerable to repeated seizures." However, they question the applicability of their own research with respect to Electroconvulsive therapy in humans: "An important caveat of our results is that it is unclear to what extent they are relevant to the use of electroconvulsive therapy in psychiatry, because the protocol employed in this study is different from that used clinically. Evidence from previous studies (Gombos et al., ; Vaidya et al., ) and from our pilot experiments indicates that treating rats either with five to ten widely spaced ECS (at 24- or 48-hr schedules) or with two stimulations only 2 hr apart does not lead to loss of hippocampal neurons".

Many expert proponents of ECT maintain that the procedure is safe and does not cause brain damage. Dr. Charles Kellner, a prominent ECT researcher and former chief editor of the Journal of ECT, stated in a 2007 interview that, "There are a number of well-designed studies that show ECT does not cause brain damage and numerous reports of patients who have received a large number of treatments over their lifetime and have suffered no significant problems due to ECT." Dr. Kellner cites a study purporting to show an absence of cognitive impairment in eight subjects after more than 100 lifetime ECT treatments. Dr. Kellner stated "Rather than cause brain damage, there is evidence that ECT may reverse some of the damaging effects of serious psychiatric illness." However, one of the authors of the cited study, Harold Sackeim, published a large-scale study shortly after this interview concluding that the type of ECT, bilateral sine wave, used in the eight patients receiving the 100 lifetime treatments routinely leads to persistent, global cognitive deficits (discussed above).