Predictors of medication prescription in nursing homes.

Objectives: To identify patient characteristics associated with higher numbers of prescribed drugs or risk of receiving one or more inappropriate medications.

Design: A cross-sectional survey using chart reviews.

Participants: A total of 414 long-stay residents of 20 nursing homes in three states

Measurements: Current medication orders, sociodemographic information, and diagnoses and health status information as indicated by the MDS. The number of routine, total, and inappropriate medications were tabulated.

Results: Higher numbers of medications were associated with higher total numbers of diseases. In addition, several diseases (congestive heart failure, hypertension, depression, anxiety, and diabetes) were associated with higher numbers of medications even after controlling for total disease burden. Cognitive impairment was associated with fewer medications after controlling for total number of diseases. Advanced age also attenuated the effect of disease burden on the number of total and routine medications. The only independent predictor of more inappropriate medications was higher numbers of routine medications.

Conclusion: Several specific disease states predispose patients to prescription of higher numbers of medication, and, these patients must be managed more carefully to prevent adverse drug-drug or drug-disease interactions. Why patients with compromised cognitive status receive fewer medications requires further study.