When you hear “nursing home,” you probably think of a place where older folks live or maybe stay temporarily to recover after surgery. But a lot of nursing home beds in the U.S. are going to people experiencing serious mental illness. In fact, as much as 90% of the patients at some nursing homes are people with schizophrenia, bipolar disorder or psychosis. And the economics of health care play a role in how this came to be.

This is according to a new investigation from APM Research Lab, part of Marketplace’s parent organization American Public Media. Elisabeth Gawthrop is a data journalist there, and she spoke with “Marketplace Morning Report” host David Brancaccio. The following is an edited transcript of their conversation.

David Brancaccio: How do so many people with mental illness find themselves in nursing homes?

Elisabeth Gawthrop: It usually starts with a hospital stint. Hospitals are supposed to discharge patients somewhere safe, somewhere they can get the care that they need, and nursing homes are a relatively easy way for hospitals to check that box.

Brancaccio: I see. This is not, say, an elderly patient with dementia, where a properly equipped nursing home would be expected to be able to care for that patient. This might be what an able-bodied person suffering from, perhaps, schizophrenia. Are nursing homes equipped to deliver appropriate care in that case?

Gawthrop: It seems like many are not. We analyzed tons of government inspection records, and we found some extreme cases in there. Sometimes people with mental illness were treated so poorly that they ended up in the hospital or even dead. And we found cases where people with mental illness hurt other people, which shouldn't happen if people are getting the right treatment, and if there's enough staff. And it's not just that there are some isolated, extreme cases. We actually analyzed every home in the country and found that nursing homes with higher rates of mental illness were more likely to be cited for abuse.

Brancaccio: And your work shows that financial incentives play a role in people with mental health conditions going to nursing homes instead of other health care facilities, perhaps more appropriate for their care.

Gawthrop: That's right. Part of this is basically that the federal government won't let Medicaid dollars pay for psychiatric institutions, so states have to pick up the bill there. But the feds will pay for nursing homes, and we're talking about a lot of money. Medicaid pays roughly $6,000 a month for a person's nursing home stay.

Brancaccio: What are ways being discussed to address this?

Gawthrop: Studies have found that many people with mental illness don't need the kind of 24/7 care that nursing homes provide, and that they could actually instead live in a house or apartment. In fact, institutions like nursing homes can actually make those conditions worse. But the problem is, the kinds of treatment programs that allow people to stay in their homes aren't available everywhere, and they often have long waitlists. So advocates for people with mental illness argue we should make it easier for Medicaid to pay for those programs. There's actually a provision in the Trump administration's big tax and spending law that could help states with that, but the law also has provisions that are likely to result in a lot of people on Medicaid losing their health insurance. So it's not clear how effective that'll be.