Hospital readmission reductions aren’t as positive as previously reported

Medicare’s Hospital Readmissions Reduction Program (HRRP) has been given a lot of credit for trimming readmission rates, but the real results may be far less impressive, according to a recent study published in Health Affairs.

Since the passage of the Affordable Care Act, general acute care hospitals have been incentivized to reduce readmissions—or face a financial penalty if they report higher-than-anticipated 30-day readmission rates for certain conditions. Since 2012, hospitals have been penalized for high readmission rates for acute myocardial infarction, heart failure and pneumonia.

Over time, studies revealed 30-day readmission rates declined after the program was established. However, a big portion of the lower readmission rates were due to increased patient risk scores, according to the Health Affairs study, which analyzed risk-adjusted readmission rates from Medicare’s 100 percent Research Identifiable Files.

Researchers found changes between risk-adjusted readmissions and rates that used fewer diagnosis codes right around the time HRRP was set to go into effect. In other words, hospitals coded differently once the program was coming into effect by increasing the number of claims having 11 or more diagnosis codes and decreasing the claims with nine or 10 diagnosis codes.

“The timing of this divergence, combined with the evidence above that documented a concurrent change in coding, suggests that a change in coding, rather than in true patient risk, explained the divergence,” study author Christopher Ody, PhD, research professor at the Kellogg School of Management at Northwestern University, et al. wrote.

This happened also as a result of an unrelated electronic transactions standards update that enabled hospitals to enter more diagnosis codes than previously allowed, but it had an impact. Patients with HRRP-targeted conditions typically had more diagnoses.

“By coincidence, the HRRP was implemented just before a change in electronic transaction standards that increased diagnostic coding and therefore created the illusion that risk-adjusted readmission rates had decreased,” Ody and colleagues wrote.

Readmission rates began to decline much faster once HRRP went into effect than during the previous time period. From January 2007 to March 2010, risk-adjusted readmission rates declined at a rate of roughly 0.18 percentage points. From April 2010 to September 2012, readmission rates dropped 0.54 percentage points among rates that used nine or fewer diagnosis codes, a 48 percent difference from the previous period.

Researchers stated the data can be interpreted two ways: either HRRP reduced readmission rates systemwide or the program had no effect on readmissions. The researchers are not the first to call HRRP into question––another recent study linked HRRP to higher mortality among heart failure and pneumonia patients.

If HRRP has not lowered readmission rates, its existence becomes questionable, and the topic should be further examined as pay-for-performance measures continue to expand throughout the healthcare system.