Auricular acupuncture, recommended by the World Health Organization (WHO) and offered as an integrative practice since 2006 by the SUS (Sistema Única de Saúde), Brazil's national health service, is safe for patients with depression and effectively reduces symptoms of this mental health disorder, according to a study conducted by researchers at the University of São Paulo (USP) and the University of Southern Santa Catarina (UNISUL).

The results of the study are reported in an article published in the journal JAMA Network Open. They confirm the efficacy of auricular acupuncture as an alternative treatment for depression, a mood disorder for which rising numbers are seeking care from the SUS, judging from data provided by the Ministry of Health.

Depression is one of the leading causes of disability worldwide, according to the WHO. In Brazil, the lifetime prevalence of depression is 15.5%, one of the highest globally, and depressive disorders account for 10.3% of years of life lost (YLL), a measure of premature mortality calculated by subtracting the age at death from the longest possible life expectancy for a person at that age.

However, fewer than half of the people affected globally receive treatment considered adequate, including psychotherapy and medication. In some countries, the proportion is less than 10%. The reasons include the high cost of antidepressants and their adverse side effects, such as gastric discomfort and decreased libido. Interest in non-pharmacological and more affordable options is growing as a result. In the United States, for example, a third of the population prefers alternative treatments for depression.

One such alternative is auricular acupuncture, an ancient Chinese technique in which thin needles are inserted into points on the outer ear with the aim of stimulating various organs, including the brain and vagus nerve. The needles are inexpensive: a pack of 50 (enough for ten sessions) costs less than BRL 10.00 (now about USD 2.00).

Simple and quick (a session lasts between 5 and 15 minutes), the technique does not require long periods of training and can be applied by nurses or physical therapists, unlike full-body acupuncture, which can only be offered by licensed practitioners. On the downside, its efficacy and safety in treating depression have not yet been completely established.

The researchers sought evidence of this kind in the study, which took place between March and July 2023, involving 74 patients whose scores on Patient Health Questionnaire 9 (PHQ9) indicated moderate or moderately severe depression. Prospective participants were not included if they had previously undergone auricular acupuncture or were severely depressed and at risk of suicide. They were given 12 sessions of 15 minutes each during a period of six weeks.

The average age of the participants was 29. Most of them (84%) were women. They were divided into two groups of 37. One received specific auricular acupuncture (SA) to treat depression according to traditional Chinese medicine, stimulating six points on the outer ear corresponding to shenmen (spirit), subcortex, heart, lung, liver, and kidney.

The other received non-specific treatment (NSA) using non-points or auricular points not associated with symptoms of mental illness: pinna, cheek, face, and four points on the helix. For ethical reasons, all participants continued with their usual treatment. The efficacy and safety of the acupuncture were assessed after four weeks, six weeks, and three months.

At the end of the follow-up period, the PHQ9 scores of 58% of the patients in the SA group were found to have improved by at least 50%. The proportion for the NSA group was 43%. This difference was not considered statistically significant.

Nevertheless, the authors note that some of the results were promising: for example, the proportion of patients with depression recovery and remission was higher in the SA group after four weeks, and a statistically significant difference in favor of the SA group was observed in remission after three months.

"Our results showed almost 60% recovering from depression thanks to specific auricular acupuncture. According to other published studies on this topic, this is similar to the recovery rate for treatment with drugs," said Daniel Maurício de Oliveira Rodrigues, first author of the article and a professor of neurology at UNISUL.

"Moreover, 46% of these participants reported cessation of symptoms, in contrast with 13% of the NSA group. For comparison, the proportion is about 35% in patients treated with drugs."

Another promising result was a lack of severe adverse effects, with no significant differences between the groups. A large majority of participants (94% in the SA group and 91% in the NSA group) reported only mild pain at the needle application site. "This evidences the safety of the intervention for more than six weeks," Rodrigues said.

More safety

"We're witnessing a veritable epidemic of mood disorders. I believe there has never been so much anxiety and depression as has been the case since the COVID-19 pandemic. Acceptance of the gold standard for treatment is far from ideal," said Alexandre Faisal Cury, a researcher in the Department of Preventive Medicine at the University of São Paulo's Medical School (FM-USP).

"In clinical practice, we see patients with chronic depression who have been taking medication for a long time and have side effects and relapses, so we need complementary options with proven benefits."

Three important lessons can be learned from the study, Faisal added. For the SUS, it validates a technique that is already in widespread use and is, in fact, the most frequently practiced integrative method in the public system. For patients, it confirms that auricular acupuncture is a safe option for the treatment of mental illness. And for health workers, it destigmatizes non-allopathic therapy.

Despite the encouraging results, the researchers pointed out that the study had noteworthy limitations and that longer studies with more participants are needed to investigate the efficacy of this treatment in greater depth. "I believe participation by more people would produce results even more favorable to the intervention," Faisal said.