NEJM: Higher intensity practice regions = more testing; no survival impact
Medicare beneficiaries who moved to a region with higher intensity medical services are associated with greater increases in diagnostic testing, more recorded chronic conditions and higher Hierarchical Condition Categories (HCC) risk scores when compared with beneficiaries who moved to a region with lower practice intensity, with no apparent survival benefit, according to a study published July 1 in the New England Journal of Medicine.

The study sought to determine the magnitude of differences in diagnostic practices, using changes in Medicare beneficiaries’ place of residence as a natural experiment. “We hypothesized that those moving to higher intensity regions would undergo more diagnostic tests and imaging services, would receive more diagnoses, and would thus have higher risk scores over time than those moving to lower intensity regions,” wrote study author Yunjie Song, PhD, of the Dartmouth Institute for Health Policy and Clinical Practice in Lebanon, N.H., and colleagues.

Researchers used the End-of-Life Expenditure Index, a Medicare spending measure closely affiliated with physician practice, to define local practice intensity. They calculated the End-of-Life Expenditure Index for each of the 306 U.S. Hospital Referral Regions (HRRs) from 2001 through 2003 and grouped HRRs into quintiles according to the intensity of hospital and physician services beneficiaries in the region.

Researchers analyzed Medicare claims data from 1999 through 2006 to measure practice trends including diagnostic testing, imaging rates, numbers of major chronic conditions and assignment of HCCs among beneficiaries who moved to regions with a higher or lower intensity of practice.

The study population was comprised of 255,264 Medicare beneficiaries enrolled in Medicare Part A and Part B who were at least 65 years old as of Jan. 1, 1999, resided in one of the 50 U.S. states or Washington, D.C., and changed residence in 2001, 2002 or 2003.

Using regression models and sensitivity analyses, researchers found that residents of higher intensity regions generally had more office visits, underwent more diagnostic tests, had a higher number of diagnoses and had higher risk scores than residents in lower intensity regions.

By the end of the study, beneficiaries who had moved to quintile 5 regions with the highest intensity of practice had risk scores that were an average of 19 percent higher than patients who moved to quintile 1 regions with the lowest practice intensity, the authors wrote. The relative risk of death at one year among beneficiaries who moved to either higher or lower intensity practice regions was identical, reported the author. After three years, researchers did not find evidence of a survival benefit in either group.

The study identified additional concerns surrounding risk adjustment. For example, higher compensation for treating patients with more diagnoses could encourage providers to perform more intensive screening and diagnostic testing. The impact on cost is clear, and effect on health outcomes is uncertain, the authors wrote.

In contrast, if risk adjustment does not account for the difficulty of caring for truly high-risk patients, some providers might be discouraged from treating such patients. Comprehensive EHRs could improve risk adjustment if they incorporate nonclinical factors that may predict patient adherence to clinical advice and clinical data like cancer stage and grade, posed the authors.

Results of the study should not be interpreted as implying that greater diagnostic intensity offers no benefits, but rather, underscores the need for research to determine the specific clinical settings in which greater diagnostic intensity does–or does not—confer a benefit, concluded the authors.