Polypharmacy and potentially inappropriate medication use as the precipitating factor in readmissions to the hospital

Background and aim: Readmission to the hospital within 30 days of discharge from the hospital is a common occurrence. Congestive heart failure is the most common cause of readmissions in the hospital. We hypothesized that irrespective of the admission diagnosis polypharmacy and potentially inappropriate use of medications (PIM) leads to readmissions within 30 days of discharge from the hospital.

Materials and methods: A retrospective study was carried out by reviewing the hospital records of 414 patients who were readmitted to the hospital within 30 days of discharge from the hospital between January 2008 and December 2009. The data was stratified to see which patients were on polypharmacy and/or on PIM. Polypharmacy was defined as use of more than 5 medications. PIM was defined as per the modified Beers criteria. Day 0 was defined as the day of discharge and day1 was defined as the day-after Admission to the hospital. Statistical analysis was carried out using a two-way analysis of variance (ANOVA) on the data to see if polypharmacy and/or PIM was related to readmission within 30 days of discharge irrespective of admission diagnosis.

Results: Polypharmacy was related to hospital readmission at day 1 and day 0, however inappropriate drug use was found to be not related at any day. Polypharmacy and PIM combined had a positive correlation to readmission only on days 1 and 0 and it was statistically significant. The use of minimal and appropriate use of drugs was statistically significant compared to polypharmacy and PIM use.

Conclusions: Polypharmacy and PIM are under recognized cause of readmissions to the hospital.