Patient flow networks absorbed 58% of COVID stress on doctors

A team of researchers led by Lu Zhong (Rensselaer Polytechnic Institute) analyzed billions of electronic medical records documenting patient visits to primary care physicians (PCPs) across the U.S. They constructed inter-regional patient flow networks to study how patient movement redistributed demand during the COVID-19 pandemic. The findings, posted on arXiv in October 2024 and updated in 2026, show that cross-regional patient flow rose from a pre-pandemic level of 2.08% to 2.81% during the pandemic. This relatively small shift in movement accounted for absorbing 58% of the excess stress on PCPs, meaning more than half of the surging demand was handled by patients migrating to less burdened regions. This represented a 43 percentage point improvement from the pre-pandemic baseline of 15% absorption.

The preprint (arXiv:2410.06031) further models that strengthening cross-regional patient flow could allow the healthcare system to absorb even more stress and reduce the demand for PCPs during large-scale disasters like pandemics or climate events. While the study focuses on primary care, the methodology could extend to specialists and hospitals. The authors emphasize that these structural insights can help policymakers design more resilient healthcare systems by encouraging patient redistribution strategies rather than simply adding capacity locally.