‘Inappropriate’ Antipsychotics to Treat Depression in Elderly Parkinson’s Patients Linked to Pneumonia Risk

Inappropriate antipsychotic medications — those approved for ills like schizophrenia but used to treat depression — given to elderly people with Parkinson’s disease increase their risk of pneumonia, a study suggests.

The study, “Risk of pneumonia associated with atypical antipsychotic use in nursing home residents with Parkinson’s disease,” was published in the Journal of Psychiatric Research.

Certain antipsychotic medications can be prescribed to help handle some of the behavioral problems evident in Parkinson’s disease (PD). But use of antipsychotics in these patients must be done cautiously, since many affect dopamine signaling — which is dysregulated in PD — and can aggravate other disease symptoms.

According to the 2019 American Geriatrics Society (AGS) Beers criteria, atypical antipsychotics are not appropriate for Parkinson’s patients, with exceptions being Nuplazid (pimavanserin), clozapine (brand names, Clozaril and FazaClo), and quetiapine (Seroquel). (Nuplazid, an oral Parkinson’s psychosis treatment that does not impact motor abilities, was approved in 2016, outside the years of this study.)

Atypical antipsychotics are considered inappropriate due to the risk of worsening Parkinson symptoms, like voluntary movements in general and swallowing abilities in particular.

Researchers in the U.S. investigated the link between inappropriate antipsychotic use and pneumonia, which can be a serious complication when swallowing or breathing are impaired.

Using Medicare data, they identified 16,161 nursing home residents diagnosed with Parkinson’s and depression (mean age, 82; two-thirds female), who were treated with antipsychotic medications between 2007 and 2010. Over a third of these individuals (37.62%; 6,126 people) were given an inappropriate antipsychotic, while the remainder were prescribed an appropriate one, with the most common being quetiapine.

Among these elderly patients, rates of dysphagia (difficulty swallowing), dementia, and levodopa use were similar between groups treated with appropriate and inappropriate antipsychotics.

Rates of pneumonia were significantly higher in patients prescribed inappropriate antipsychotics, 18.78% vs. 16.35%, than in those given appropriate ones over a six-month follow-up. Inappropriate antipsychotic use was also associated with a 20% greater chance of pneumonia, statistical analyses found; this finding was validated through sensitivity analyses that work against uncertainty in given sets of assumption.

Researchers also noted that rates of stopping antipsychotics were higher among those on inappropriate medications (21.17% vs. 15.22%).

“The risk of pneumonia was significantly higher for inappropriate AAP [antipsychotic] users in comparison to the appropriate AAP users,” the researchers wrote.

“The study findings suggest that selection of appropriate antipsychotics in PD is critical to prevent serious adverse events related to antipsychotic use in PD, given that pneumonia is one of the most common causes of mortality in PD patients. Further research is needed to evaluate the risk of pneumonia in PD patients using newer antipsychotic medications,” they concluded.