Changing Prescription Profiles for Diabetics in Nursing Homes

According to recent estimates, between 25% and 35% of nursing home residents have diabetes mellitus. The authors of a paper published in JAMDA sought to describe how prescribers who care for nursing home residents employ glucose-lowering medications to manage diabetes.

The researchers used a random 20% of Medicare enrollees’ claims for Part A and D from the Minimum Data Set (MDS) for 2007-2010. Researchers obtained information about beneficiaries from the Medicare claims data (e.g., Medicare eligibility, patient demographics, hospitalizations, and prescriptions that were dispensed for each patient). They also obtained information about the nursing homes from the Minimum Data Set and Online Survey, Certification, and Reporting database.

The study cohort included residents with diabetes who were at least 65 years old and had been residents for more than 90 days. All subjects began a glucose-lowering treatment between January 2008 and December 2010. The authors examined all noninsulin glucose lowering medications (biguanides, sulfonylureas, thiazolidinediones, dipeptidyl peptidase-4 inhibitors, meglitinides, alpha-glucosidase inhibitors, glucagon-like peptide-1 receptor agonists, and amylin mimetics). They classified insulins as short-acting, intermediate-acting, or long-acting and subcategorized them by onset of effect, either basal or bolus.

The cohort included 11,531 nursing home residents in 7,518 different nursing homes. The mean age was 81 years and 60% of the cohort was female. Residents had many comorbidities, with the most common being hypertension (77.8%), congestive heart failure (29.0%), and ischemic heart disease (26.1%). Almost one-third (30.1%) were hospitalized in the year before they began glucose-lowering medication.

The researchers report that the newer glucose-lowering medications (DPP-4 inhibitors and GLP-1 agonists) did not grow in market share in nursing homes. They credited limited prescriber experience, cost, route of administration, Medicare Part D plan formulary inclusion and status, lack of studies in older patients, and concern about undesirable side effects in a frail population.

The majority of nursing homes were for-profit (72.7%), had 100 beds or more (67.2%), and were part of a corporation with multiple facilities (55.3%).

A key finding was a dramatic change in how prescribers used insulin. They tended to use more rapid-acting insulin. In the first quarter of 2008, 21% of newly initiated insulin was asprartane; by the third quarter of 2010, that percentage had risen to 40%, and use of both regular and lispro insulins decreased.

Second-generation sulfonylureas, once the cornerstone of diabetes pharmacotherapy, were used significantly less often than expected. The researchers postulate that the decline was related to the FDA’s 2007 boxed warning that cautioned against cardiovascular adverse events including myocardial infarction with the thiazolidinedione rosiglitazone, plus concerns about increased heart failure risk with both rosiglitazone and pioglitazone.