Is polypharmacy a risk factor for aspiration pneumonia in older adults? A case-control study

The incidence of aspiration pneumonia and the number of medicines prescribed increase with older age. Many medicines pose a risk for aspiration pneumonia, especially those that decrease swallowing function. Older adults with polypharmacy often receive a combination of these medicines. This study aimed to clarify whether polypharmacy is a risk factor for aspiration pneumonia.

Older adults aged ≥ 65 years receiving oral medicines were included in this case-control study. Patients hospitalized for pneumonia served as the case group, and other age-matched hospitalized patients served as the control group. Patient data were collected retrospectively, and logistic regression analysis was performed using items that showed significant differences in the univariate analysis as explanatory variables.

Logistic regression analysis revealed that the number of medicines was not a risk factor for aspiration pneumonia; however, it was associated with the Functional Oral Intake Scale score, male sex, body mass index, and number of comorbidities.

Although polypharmacy is often defined only by the number of medicines, it is not a risk factor for aspiration pneumonia. A detailed comparison of prescription medicines between the pneumonia and non-pneumonia groups is necessary.