Common antidepressant shows no benefits, higher risk of death for dementia patients

PLYMOUTH, United Kingdom — A team of researchers is urging the public to stop using a common antidepressant as a treatment for dementia-related symptoms. Their study finds mirtazapine failed to provide any benefit for dementia patients dealing with agitation. Moreover, patients taking mirtazapine had a higher likelihood of death than those taking a placebo instead.

Agitation is a common symptom of dementia; a disease which impacts more than six million people over age 65 in the United States. Study authors say those with agitation typically display inappropriate verbal, vocal, or physical movements. This behavior is often aggressive.

Although doctors usually attempt to ease agitation through non-drug means first, some patients end up taking prescription drugs when this doesn’t work. Unfortunately, previous studies have found that antipsychotics can raise the risk of death among dementia patients. With that in mind, study authors examined how well antidepressants work instead.

A team from the University of Plymouth recruited 204 people in the United Kingdom with a possible or likely case of dementia for the double-blind trial involving mirtazapine. Half the group took mirtazapine for several weeks while the other half took a placebo.

After 12 weeks, researchers found patients on mirtazapine had no less agitation in comparison to the control group. There were also more deaths among the mirtazapine group (seven) by the trial’s 16th week than in the placebo group (one).

Rethinking Alzheimer’s treatment

“Dementia affects 46 million people worldwide – a figure set to double over the next 20 years. Poor life quality is driven by problems like agitation and we need to find ways to help those affected. This study shows that a common way of managing symptoms is not helpful – and could even be detrimental. It’s really important that these results are taken into account and mirtazapine is no longer used to treat agitation in people with dementia,” says lead researcher Professor Sube Banerjee, Executive Dean of the Faculty of Health and Professor in Dementia, in a university release.

“This study has added important information to the evidence base, and we look forward to investigating further treatments that may help to improve people’s quality of life.”

“Unnecessary prescribing of antipsychotics to people with dementia is dangerous and associated with a higher risk of death, which is why we’ve been campaigning hard to reduce levels since the late 90s, saving tens of thousands of lives. The gold star treatments for agitation don’t involve drugs and are tailored to the person – like arts and crafts or movement to music. In recent years antidepressants – like mirtazapine – have been considered a fallback if non-drug approaches don’t work,” adds Dr. Richard Oakley, Head of Research at Alzheimer’s Society.

“While only a small study, these results suggest a rethink is needed. Not only was the drug ineffective at reducing agitation, it was associated with more deaths, suggesting mirtazapine should be avoided in Alzheimer’s – and research carried out to understand its effects in other types of dementia.”

Researchers published their findings in The Lancet.