Researchers have failed to find evidence of a strong link between hospital readmission rates and mortality rates, calling into question concerns that the two might be inversely related.

For the study, which appeared in the Journal of the American Medical Association, researchers examined three years of Medicare data, assessing 30-day readmission and mortality rates among patients hospitalized with heart attack, pneumonia and heart failure. They found no relationship between readmissions and mortality for heart attack and pneumonia patients and only a weak association for heart failure patients.

A number of researchers and policy experts have suggested recently that hospitals with lower mortality rates could, as a result, have higher readmission rates. One reason, they say, is because very sick patients who are kept alive are then eligible to be readmitted.

The authors of this latest study, including Dr. Harlan Krumholz, a professor of cardiology at Yale University, New Haven, Conn., argued instead that CMS data reveals no such relationship.

“These findings should allay concerns that institutions with good performance on (risk-standardized mortality rates) will necessarily be identified as poor performers on their (risk-standardized readmission rates),” the authors wrote in the study, adding that they had identified high and low performers on readmissions at all levels of mortality.

“Our findings indicate that many institutions do well on mortality and readmission and that performance on one does not dictate performance on the other,” they wrote.