Cindy Parks Thomas

Introduction
Nurse practitioner (NP) prescribing continues to be a contentious policy issue, and studies systematically examining NP prescribing are lacking. The aim of this study was to conduct a descriptive analysis comparing the prescribing services of NPs with those of primary care physicians (PCPs) in providing care to Medicare beneficiaries.
Methods
Part D drug claims of beneficiaries who saw an NP or a PCP in 2009 and 2010 were examined for differences in the types of medications prescribed, the volume of prescriptions, and the duration of prescriptions across all drug classes in Medicare Part D.
Results
Data for 164,681 beneficiaries were analyzed. Results showed the same top 20 types of medications and the same share of generic medications for NP and PCP prescriptions. Differences in prescribing patterns were found for the number of prescriptions and for the duration of the prescriptions (days’ supply per claim). NP beneficiaries received, on average, approximately one more 30-day prescription per year than PCP beneficiaries. The mean duration for an NP prescription claim was 3 days shorter than that for a PCP prescription claim, indicating that NP beneficiaries need refills sooner than PCP beneficiaries. This pattern existed in most drug classes and was more pronounced in behavioral drug classes, such as antidepressants, antipsychotics, psychotherapeutics, and opioids and in patients with more comorbidities. Differences in state scope of practice laws did not affect these prescribing patterns.
Conclusions
Key differences were observed in the number and duration of prescriptions written by NPs and PCPs. Further research is needed to understand the impact of differences in NP and PCP patient populations on provider prescribing, such as the higher number of prescriptions issued by NPs for beneficiaries in moderate and high comorbidity groups and the implications of the duration of prescriptions for clinical outcomes, patient-provider rapport, costs, and potential gaps in medication coverage