Association of Medicare Spending With Subspecialty Consultation for Elderly Hospitalized Adults.

Importance: High use of subspecialty care is an important source of health care spending. Medical subspecialty care in particular may duplicate the scope of practice of the primary attending physicians for patients hospitalized for medical conditions. Under value-based payments, which aim to control overall spending during an episode of hospitalization (including Part B physician fees), subspecialty consultations may be a target for hospitals working to reduce costs. Objectives: To measure the use of subspecialty consultation for Medicare beneficiaries hospitalized for nonsurgical conditions; to compare payments for consultative and nonconsultative care, adjusted for case mix and demographics; and to measure variation in payments across hospital referral regions (HRRs). Design, Setting, and Participants: This retrospective cross-sectional study included a 15% random sample of Medicare fee-for-service beneficiaries enrolled in Parts A and B and identified all discharges after acute care hospital stays for nonsurgical conditions from January 1 through December 31, 2014. A total of 735 627 discharges were included. The analyses were conducted from December 1, 2017, through February 12, 2019. Total Part B payments were extrapolated to the population of Medicare fee-for-service beneficiaries. Main Outcomes and Measures: Probability of any consultation during a hospitalization was estimated using logistic regression. The number of consultations per stay and the number of consultative visits per hospital day were estimated using Poisson regression. Part B payments for consultative and nonconsultative care were estimated using generalized linear regression with gamma-log link. All models were adjusted for patient demographics and case mix. Payment models also included HRR fixed effects. Results: A total of 735 627 discharges from 4534 hospitals in 2014 were included in the analysis (41.2% men and 58.8% women; mean [SD] age, 79.6 [8.9] years; 84.7% white, 10.1% black, and 5.2% other race). After adjusting for patient case mix and demographics, a 6-fold variation between the top and bottom quintiles of hospitals (relative difference, $401 [95% CI, $368-$434]) and HRRs (relative difference, $363 [95% CI, $337-$389]) was found in payments per stay for consultative care. Part B payments for consultative care by medical subspecialists accounted for 41.3% of payments for physician visits during hospitalization and totaled $1.3 billion in 2014. Conclusions and Relevance: The substantial variation in the use of subspecialty consultative care suggests potential opportunities for cost savings.