In an era of physician shortages and insurance expansion, the American health system is struggling to keep pace with increasing demand from patients. Although the last decade has produced some growth in the number of American medical schools, residency programs havent kept pace. In addition, the aging of the Baby Boomer generation will bring a silver tsunamiof patients into the healthcare system. The culmination of these factors has led to massive additions in advanced practice providers (APPs): physicians assistants and nurse practitioners.
as they would with any other system reform. Numerous studies of APPs have been performed in the past to examine quality and costs. However, a common criticism of these studies is that they arent apples to apples comparisons between physicians and APPs. Typically, the argument states that physicians see sicker, more complicated patients while nurse practitioners and physicians assistants see younger, healthier patients.
A recent study in the journal Medical Care sought to address this critique. Utilizing retrospective nationwide data from CMS Chronic Disease Data Warehouse, the researchers compared the health outcomes for elderly, diabetic patients who received care from only nurse practitioners vs. only physicians. Specifically, the study examined rates of potentially avoidable hospitalizations.
The average patient age was 77 years old with diabetes and 2 additional co-morbidities. Patients who solely received care by a nurse practitioner had decreased risk of avoidable hospitalization compared to patients who saw only physicians (OR 0.9; 95% CI 0.87-0.93). Overall mortality for both groups was similar.
As with any retrospective study, differentiating between correlation and causation can be difficult. To address this, the authors performed several additional analyses utilizing advanced statistics to examine for potential confounding factors. Even when controlling for factors such as age, burden of comorbidity, Medicaid eligibility, and others, the authors found similar results.
Although encouraging, these findings will by no means end the ongoing debate on the role of APPs in todays health system. Debates on autonomy, training, and scope of practice are likely to continue for the foreseeable future. Still, these results are promising in the realm of patient safety. should further examine this issue in other settings and patient populations.
commentary by Kyle Fischer
Background: Few comparisons exist of the quality of primary care provided by nurse practitioners (NPs) versus physicians.
Methods: Patients with a diagnosis of diabetes in 20072010 (n=345,819) who received all primary care from NPs or from generalist physicians in a given year were selected from a national sample of Medicare beneficiaries. We compared the rate of potentially preventable hospitalizations among patients who received primary care from NPs versus generalist physicians. Various statistical methodsincluding multivariable analysis, inverse probability weighting of propensity score, nonpooling propensity score adjustment and matching, and instrumental variable (IV) analysiswere used to control for differences in patient characteristics between the 2 groups.
Results: Patients who received all of their primary care from NPs or from physicians differed by age, sex, race/ethnicity, socioeconomic status, residential area, and number of provider visits in the previous year. Nonpooling propensity score matching substantially reduced the differences, but neither IV approach satisfactorily reduced the differences. In multivariable analyses, receipt of primary care from an NP was associated with a decreased risk of hospitalization for potentially preventable conditions (OR: 0.90; 95% CI, 0.870.93). Similar results were found using conditional logistic regression models with propensity methods. We found smaller reductions in our analyses of other hospitalizations (OR: 0.96; 95% CI, 0.950.98). Both IV analyses showed associations between NP care and lower potentially preventable hospitalizations, but only 1 result was statistically significant.
Conclusions: Using potentially preventable hospitalizations as a quality indicator, primary care provided by NPs was at least comparable with that provided by generalist physicians.