Tag: antispychotics

Older Antipsychotic Drugs Linked to Breast Cancer

Source: National Cancer Institute

A number of commonly prescribed older antipsychotic drugs, and some newer ones, are associated with a significant increase in risk of breast cancer, according to a new study.  The findings are published online in the Journal of Clinical Psychopharmacology.

Previous research uncovered the link between antipsychotic drug use, prescribed for a wide array of mental health problems, and breast cancer risk. This study compared newer antipsychotics to older drugs, and examined how the drugs affect prolactin levels, which have been associated with breast cancer. However, many antipsychotics elevate prolactin levels and can produce side effects such as menstrual cycle irregularities, abnormal breast milk production and abnormal breast tissue growth.

“Many women with psychiatric illnesses such as schizophrenia and bipolar disorder will take antipsychotics for decades, and they are essential to keeping symptoms in check,” said first author Tahir Rahman, MD. “But both older antipsychotic medicines and some newer drugs raise levels of prolactin and increase the risk of breast cancer, which is concerning. Our study confirms findings from a smaller European study that advised women and their doctors to first try drugs that don’t affect prolactin levels. We agree with that advice and believe psychiatrists should start to monitor prolactin levels in their patients taking antipsychotics.”

Antipsychotic drugs were classified into three categories, based on their established effects on prolactin. Category 1 included drugs associated with high prolactin levels, such as haloperidol, paliperidone and risperidone. Category 2 had mid-range effects and included iloperidone, lurasidone and olanzapine. Category 3 had low-effect drugs such as aripiprazole, asenapine, brexpiprazole, cariprazine, clozapine, quetiapine and ziprasidone.

Comparing the three drug categories to anticonvulsant drugs and lithium, the relative risk of breast cancer was 62% higher for women who took Category 1 drugs and 54% higher for those taking Category 2 drugs, whereas Category 3 antipsychotics were not associated with any increase in breast cancer risk.

“Certain drugs are known to elevate prolactin, and the women taking those drugs were more likely to have breast cancer,” Dr Rahman said. “But we didn’t detect any increased risk in women taking antipsychotics that don’t raise prolactin levels.”

In mouse models, prolactin can help weaken systems keeping precancerous lesions from becoming breast cancer. In humans, prolactin levels tend to be lower in women who have had more children at a younger age than in women who have fewer children or wait until they are older to do so.

In this study using data collected from 2012 through 2016, the research team performed a retrospective, observational study of breast cancer risk in women ages 18 through 64 who took antipsychotics.

The researchers identified which patients were treated for breast cancer during a 12-month period and matched that information to patients taking antipsychotic drugs. Of the 540 737 women in the database taking antipsychotics, only 914 were identified as having breast cancer – a significant number of whom were taking drugs known to increase prolactin.

“Antipsychotic medications can be lifesaving for patients who have psychotic episodes where they experience symptoms such as hallucinations and delusions,” Dr Rahman said. “In recent years, the drugs have been approved to treat other conditions, too, including depression and bipolar disorder. As those high-prolactin agents are used more widely, the number at risk could increase. We’ve been advising against using these high-prolactin agents in women who already have breast cancer, but we’d like to investigate whether keeping prolactin levels lower even might prevent some of these cancers.”

In another recent study, the antipsychotic drug aripiprazole did not increase prolactin levels in women and that a few women who began the study with high prolactin levels experienced decreases in prolactin levels after 12 weeks of treatment.

Those findings, combined with preclinical evidence of the anticancer effects of some antipsychotics, have inspired Dr Rahman and colleagues to propose repurposing some antipsychotic drugs in the fight against breast cancer.

“We don’t want to alarm patients taking antipsychotic drugs for life-threatening mental health problems, but we also think it is time for doctors to track prolactin levels and vigilantly monitor their patients who are being treated with antipsychotics,” Dr Rahman said.

Source: Washington University School of Medicine

Sustained Antipsychotic Benefits of Pimavanesirn Shown in Study

Photo by Kindel Media from Pexels

Evidence of the sustained benefits of an investigational antipsychotic treatment for people with dementia-related psychosis has been published.

Up to half of the 45 million people worldwide who are living with Alzheimer’s disease will experience psychotic episodes, a figure that is even higher in some other forms of dementia. Psychosis is linked to a faster deterioration in dementia, and currently there is no safe and effective treatment for it. Widely-used antipsychotics have significant drawbacks in people with dementia, leading to sedation, falls and increased risk of deaths.

Pimavanserin works by blocking serotonin 5HT2A receptors, with no interaction with dopamine receptors. In the US, it is licensed to treat hallucinations and delusions in people with Parkinson’s disease psychosis.

To test this drug, a clinical trial was conducted in 392 people with psychosis associated with Alzheimer’s disease, Parkinson’s disease, Lewy body, frontotemporal, or vascular dementia. All participants were given pimavanserin for 12 weeks, with those reaching a certain level of symptom improvement were then assigned to pimavanserin or placebo for up to 26 weeks. Due to positive efficacy results however, the trial was concluded early. 

Of the 351 participants, 217 (61.8%) had a sustained initial treatment benefit, of whom 112 were assigned to placebo and 105 to pimavanserin. Relapse occurred in 28/99 (28.3%) of the placebo group, compared to 12/95 (12.6%) of the pimvanserin group, with pimvanserin more than halving the relapse rate and significantly improving the sustained benefit.

Professor Clive Ballard, Executive Dean of the University of Exeter Medical School, said: “Psychosis affects up to half of all people with dementia, and it’s a particularly distressing symptom – yet there’s currently no safe and effective treatment. Currently used antipsychotics are known to cause harms, and best practice guidelines recommend prescribing for no longer than 12 weeks for people with dementia as a result. We urgently need alternatives. It’s exciting that the relapse rate in the pimavanserin group was lower than the placebo group, indicating that the treatment benefits may be sustained over time. We now need longer and larger scale trials to explore this further.”

The trial found headache, urinary tract infection and constipation occurred more frequently in the pimavanserin group, but there was no increase in mortality or the other serious events, such as stroke, which are seen in other antipsychotics.

The full paper is published in the New England Journal of Medicine.

Source: EurekAlert!