By Susan Shand
03 July, 2018

A new study of a popular medicine could ease concerns about its link to depression.

The drug, efavirenz, is used to fight the human immunodeficiency virus, HIV. The virus weakens the body's natural defenses.

Some researchers once feared that using efavirenz caused patients to become depressed or consider the possibility of suicide. Researchers working in Uganda reported recently that the drug did not cause those negative side effects.

A newly diagnosed HIV-positive woman receives treatment at the Mildmay Uganda clinic, Kampala, Feb. 27, 2014.
A newly diagnosed HIV-positive woman receives treatment at the Mildmay Uganda clinic, Kampala, Feb. 27, 2014.

Efavirenz is a low-cost, once-a-day pill used around the world to treat and prevent HIV and the disease AIDS. It is "the treatment of choice" in most of the world, especially in countries that depend on international aid to treat HIV. That information comes from Mark Siedner of the Africa Health Research Institute.

Some studies in the United States and Europe found the drug increased patients' risk of depression or suicide. But other studies did not reach the same finding.

The mixed results led many doctors in the United States to suggest more costly but possibly safer drugs.

Siedner wanted to take another look at the risk of depression, this time in Africa. From 2005 until 2015, he and a team of Ugandan and U.S. doctors followed 694 patients. All of the patients took either efavirenz or another antiretroviral medication. The doctors asked the subjects whether they experienced depression or ideas of suicide.

No difference

A report on the study was published in the Annals of Internal Medicine.

Siedner says he and his team found there was no difference between the two treatments.

He told VOA, "In other words, efavirenz was not associated with a risk of depression. If anything, there seems to be a signal that...potentially it was associated with a decreased risk. But it wasn't a strong enough [signal] for us to say that."

The researchers also noted that 17 of the patients died during the study. But there was not a single death from suicide.

Siedner has two possible explanations for why their findings differed from those in Western countries. He said one possible cause "is that every single ethnic group in the world, of course, is different, and different in many different ways. Different socially, different environmentally, and in this case, they may be different genetically." His team is looking at whether the genes that control the metabolism of the drug have an effect to play in this story.

A second explanation could be the effectiveness of the drug. Because efavirenz is so powerful, it could be keeping people healthier than they expected. As a result, patients might be less likely to report depression or suicidal thoughts.

Anthony Fauci, a leader in AIDS research for over 30 years, praised the new study as important. He heads the U.S. National Institute of Allergy and Infectious Diseases.

He said the study pushes back against "the initial observation of suicidal ideation, and suicide and depression" as caused by efavirenz.

He told VOA, "I think now what you're seeing is that with these conflicting reports, it's likely someone will come in [with] the proposal to do a randomized study and take a look. So the story isn't ended with this paper."

As more research on the safety of efavirenz is done, new and less costly drugs that might replace it are likely in the future. One of them, dolutegravir, might also create a health risk, however. A study in Botswana found dolutegravir was linked to neural tube defect in embryos. That means it might not be safe for pregnant women.

As always, more research is needed to confirm whether this is a common problem or only affected the population in Botswana.

I'm Susan Shand.

This story was reported by Sadie Witkowski of VOA News. Susan Shand adapted it. George Grow was the editor.

Write to us in the Comments Section or on 51VOA.COM.

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Words in This Story

negativeadj. harmful or bad; unwanted

associate – v. to think of one person or thing when you think of another person or thing

metabolism – n. the chemical processes by which a plant or an animal uses food and water to grow and heal and to make energy

randomizedadj. of or related to something lacking aim, direction or rule

neural tube – n. a structure from which the brain and spinal cord form