Anticholinergic drugs linked to higher risk for pneumonia in elderly

Taking commonly used medications with anticholinergic effects is associated with a significantly higher risk for developing pneumonia, according to a study published recently in the Journal of the American Geriatrics Society.

The study of more is the first to address whether oral anticholinergic medications affect the risk of pneumonia in older people.

Dr DublinSenior author Sascha Dublin, MD, PhD, a Group Health physician and Group Health Research Institute (GHRI) associate investigator, and colleagues conducted a nested case-control study including more than 3,000 Group Health immunocompetent patients aged 65 to 94 years who were living in the community-not in nursing homes.

“What this means is, from within a well-defined population, we identified cases of pneumonia and people without pneumonia [controls],” Dr Dublin said. “They were all patients at Group Health, a managed care system that integrates care and coverage.”

Related: Corticosteroids recommended for severe penumonia

The researchers identified pneumonia cases (n=1,039) according to ICD-9 diagnosis codes from 2000 to 2003 and validated them using chart review. Controls (n=2,022) were matched 2:1 to cases according to age, sex, and year.

“We ascertained anticholinergic medication exposure using prescription data, and we had partial tracking of over-the-counter anticholinergics too,” Dublin said. “We used conditional logistic regression to analyze the link between anticholinergic use and pneumonia, adjusted for comorbidities.”

They found a statistically significant association between both acute and chronic utilization of commonly used medications with anticholinergic effects and a higher risk for developing pneumonia in older people, according to Dr Dublin.

Dr Dublin and colleagues observed acute use of anticholinergics in 59% of cases and 35% of controls (adjusted odds ratio (aOR)=2.55, 95% confidence interval (CI)=2.08–3.13). They observed chronic use of anticholinergics in 53% of cases and 36% of controls (aOR 2.07, 95% CI=1.68–2.54).

“Our study adds to substantial evidence suggesting that these medications are high risk,” Dr Dublin says. “Many older people use these medications. And pneumonia is a common cause of illness and death in older people. Many of these medications are already included in lists of high-risk medications in older people, and many institutions are already doing work to try to reduce use.  Our results support the importance of this work and confirms that clinicians should review them regularly to identify potential risks.”

Related:Anticholinergic medications linked to dementia

It’s especially important for patients to tell their doctors about any over-the-counter medications that they are taking, Dr Dublin advises.

“Patients often assume over-the-counter medicines must be safe for them, but this isn’t always true,” she says. “No one should stop taking a medication without consulting their healthcare provider. But together, patients and providers can weigh the pros and cons-and discuss alternatives, making decisions in a shared decision-making process.

“Sometimes providers have to prescribe a medication with anticholinergic effects because it is best for their patient,” Dr Dublin added.

But there are possible alternatives for anticholinergic drugs for:

• Insomnia: Consider trying melatonin or behavior change strategies (such as exercising more or avoiding caffeine) instead of benzodiazepines or antihistamines.

• Depression: Instead of tricyclic antidepressants such as doxepin (Sinequan), a provider might suggest a selective serotonin reuptake inhibitor (SSRI), such as citalopram (Celexa) or sertraline (Zoloft), with fewer anticholinergic effects. Counseling can also help treat depression.

• Allergies: Instead of first-generation antihistamines such as diphenhydramine (Benadryl) or chlorpheniramine (Chlor-Trimeton), consider a second-generation antihistamine such as loratadine (Claritin).

• Urinary incontinence: It’s more difficult to find alternative medications to antimuscarinics for bladder control such as oxybutynin (Ditropan); but behavior change strategies can be more effective. For instance, it can help to set an alarm as a reminder to urinate every hour or two.

“It isn’t clear why anticholinergic medications might raise pneumonia risk, but one possibility is that by causing sedation and altered mental status, they raise the risk for breathing problems-and lung infections,” according to Dr Dublin. “But more research is needed.”

Related: High-dose flu vaccine more effective in prevention of influenza hospitalizations in elderly