The aim of this study was to assess the occurrence of polypharmacy and excessive polypharmacy in very old hospitalized patients based on their comorbidities.
The documentation of patients aged 80 years or older admitted to our department in the year 2010 was analyzed. Based on the Charlson index of comorbidity, a multiple logistic regression model with stepwise backward elimination was performed. Patients were stratified by gender and four age-groups, and factors of a change in the number of medications during the hospital stay were assessed.
Chronic pulmonary disease [odds ratio (OR): 2.40], diabetes mellitus with (OR: 4.65) or without (OR: 1.65) microvascular complications, congestive heart failure (OR: 2.37), connective tissue disease (OR: 3.02), and peripheral vascular disease (OR: 2.30) were statistically significantly associated with polypharmacy, while some of these diseases were also associated with excessive polypharmacy. The number of medications showed a gradual decrease with age, which was concordant with a decrease in total Charlson index score. “Admission for myocardial infarction” was associated with an increase in pharmaceuticals during hospital stay, whereas a known diagnosis of dementia or metastatic malignant disease was protective against a further increase in medications.
Several medical conditions seem to predispose to polypharmacy in very old patients. To attain old age seems to be associated with few comorbidities, which reduces the need for a high number of pharmaceuticals. Physicians should pay attention to the identified predictors in very old patients, as polypharmacy may lead to adverse events and unnecessary hospitalization.