Polypharmacy and possible drug-drug interactions among diabetic patients receiving home health care services.

Objectives: In this study, we examined the drug regimens of diabetic patients receiving home health care services to measure the prevalence of polypharmacy and to assess the likelihood of drug-drug interactions, a consequence of polypharmacy.

Design: The sample consisted of 139 diabetic patients who received home health care services from one home health agency in a large mid-Atlantic city. The data were collected from March 1, 1998 to September 30, 1999. Information regarding medications was collected by the home health nurse during the initial home visit and was recorded on the medication sheet in the patient's clinical record. Any changes in medications were noted on the medication sheets.

Methods: We identified all systemic medications prescribed for 139 home health patients. To assess drug-drug interactions, we used Micromedex formulary DRUG-REAX System.

Outcomes: We calculated (1) the number of systemic medications taken, and (2) the number of possible severe, moderate, and mild drug-drug interactions.

Results: We found that the average number of medications taken was 8.9 (SD 3.4) prescribed medications per day. Our results show that 38.8% of the patients in the sample could potentially be subject to at least one severe drug-drug interaction. Nearly all of the patients (92.8%) were at risk for moderate drug-drug interactions, and 70.5% could have mild drug- drug interactions.

Conclusion: We conclude that polypharmacy is a concern for home health care patients with diabetes and the potential for drug-drug interactions is substantial. Our results indicate that the drug regimens of diabetic patients should be monitored systematically to avoid adverse events such as hospitalization. Family practitioners and home health care takers are in a unique position to identify polypharmacy and to modify drug regimens.