Background: Changes in the location and availability of surgical services change the distances that patients must travel for surgery. Identifying health effects related to travel distance is therefore crucial to evaluating policies that affect the geographic distribution of these services. We examine the health outcomes of coronary artery bypass graft (CABG) patients in Pennsylvania for evidence that traveling further to a hospital for a one-time, scheduled surgical procedure causes harm.
Methods: We perform instrumental-variable regressions to test for the effect of distance to the admitting hospital on the in-hospital mortality and readmission rates of 102,858 CABG patients in Pennsylvania during 1995-2005, where the instrumental variables are constructed based on the quality of and distance to nearby CABG hospitals.
Results: We found that patients living near a CABG hospital with acceptable quality traveled significantly less and if they were high-risk, had lower in-hospital mortality rates. Readmission rates in general are not affected by patients' travel distance.
Discussion: The positive correlation between travel distance and health outcomes observed by previous studies may reflect the confounding effects of behavioral factors and patient health risks. We found instead that living further from the admitting hospital increases in-hospital mortality for high-risk CABG patients. More research on the possible causes of these effects is necessary to identify optimal policy responses.