Outpatient follow-up, readmission rates higher for direct-arrival vs. transferred-in MI patients, study finds

Likelihood of follow-up in an outpatient clinic and 30-day mortality and readmission risks were compared between patients who presented directly to a hospital with MI and those who were transferred for MI care.

Patients who present directly to a hospital with myocardial infarction (MI) may have better outpatient follow-up rates and lower readmission rates than patients with MI who are transferred in, according to a recent study.

Researchers looked at Medicare claims data from 451 U.S. hospitals participating in the Acute Coronary Treatment and Intervention Outcomes Network Registry-Get With the Guidelines to determine how well patients transferred to a facility for MI care were transitioned back to communities. Likelihood of follow-up in an outpatient clinic and risks of all-cause mortality and all-cause or cardiovascular readmission at 30 days after MI were compared between patients who presented directly to a hospital with MI and those who were transferred for MI care. The study results were published online Jan. 26 by Circulation: Cardiovascular Quality and Outcomes.

The study included postdischarge outcomes of 39,136 patients at least 65 years of age who were discharged alive after acute MI from 2007 to 2010. Of these patients, 14,060 (36%) were transferred for MI care, with a median distance traveled of 43 miles (interquartile range, 27 to 68 miles). Hospitals that transferred patients had a median bed size of 74 (interquartile range, 27 to 145), and most were nonteaching hospitals. Rates of percutaneous coronary intervention capability and coronary artery bypass grafting capability were 8% each at transferring hospitals. Of the hospitals that received patients for transfer, 22% were teaching hospitals and 91% had coronary artery bypass grafting capability. Median bed size of receiving hospitals was 337 (interquartile range, 230 to 505).

Patients who were transferred for care were slightly younger than those who arrived directly, with a median age of 73 years versus 74 years. They were also more likely to be men and more likely to be white. However, transferred patients were less likely to have previous MI, heart failure, and previous revascularization. Patients who were transferred for care were less likely to receive outpatient follow-up 30 days after discharge (risk-adjusted incidence, 69.9% vs. 78.2%; hazard ratio, 0.90; 95% CI, 0.87 to 0.92) than those who were direct arrivals; they also had higher adjusted 30-day risks for all-cause (14.5% vs. 14.0%; hazard ratio, 1.08; 95% CI, 1.01 to 1.15) and cardiovascular readmissions (9.5% vs. 9.1%; hazard ratio, 1.13; 95% CI, 1.04 to 1.22). Risk-adjusted 30-day mortality rates, however, did not differ significantly between transferred and direct-arrival patients (1.6% vs. 1.6%; hazard ratio, 1.05; 95% CI, 0.86 to 1.27).

The authors noted that they could not account for the potential effect of regional care networks on patterns and transfers of follow-up, that they had no data on barriers to care after hospitalization, and that their results may have been affected by confounding, among other limitations. However, they concluded that interhospital transfer is fairly common among older adults who present with acute MI and that transferred patients are less likely to receive timely outpatient follow-up and more likely to be readmitted 30 days after discharge than those who present directly to a hospital for acute MI care, although they are not at increased risk of mortality during that time. “These patients may represent an opportunity for improving post-MI discharge care coordination among those initially transferring in,” the authors wrote.