America’s public hospitals are privatizing. That’s bad news for low-income patients.

Over the past four decades, US hospitals have gradually moved from public hands to private ones. The share of hospitals owned and operated by a government body — as opposed to a private entity, either a for-profit enterprise or a nonprofit — declined by 42 percent from 1983 to 2019.

That trend has brought serious consequences for the poorer patients who seek care at these hospitals. When private companies assume control of public hospitals, low-income patients on Medicaid lose access to health care, according to new research on this longstanding but under-analyzed...