Impact of potentially inappropriate medications on emergency ambulance admissions in geriatric patients after discharge.

This study aimed to determine the risk of emergency admission by ambulance in patients taking potentially inappropriate medications (PIMs). We included 273,932 patients aged over 75 years of age admitted between January 1, 2019, and December 31, 2019, using the Japan Medical Data Center medical insurance database containing anonymized patient data. We excluded patients without a history of admission. In total, 22,017 patients were included in the analysis. The commonly prescribed PIMs were diuretics, benzodiazepines, non-benzodiazepines, H2 receptor blockers, and nonsteroidal anti-inflammatory drugs. The primary endpoint, which was the incidence rate of emergency admission by ambulance after discharge, was 31.5/100,000 person-days in patients aged over 75 years. The secondary endpoints, which were risk factors for admission, included the use of PIMs, age over 85 years, male sex, history of congestive heart failure, history of chronic respiratory disease, and the number of medications at discharge. In contrast, body mass index was observed to have a negative trend in relation to admission. In conclusion, we observed 31.5/100,000 person-days of emergency admission by ambulance after discharge in patients aged over 75 years. Administration of PIMs upon discharge poses a risk for admission. To avoid emergency admissions via ambulances, it is important to discontinue or reduce the prescription of PIMs while considering the risks and benefits for each patient.