The current presidential administration’s hard-line stance on immigration has caused serious concerns among health care employers, as any efforts that could shrink the available pool of workers will only exacerbate persistent workforce pressures.

But in addition to representing a sizable chunk of the average nursing home’s staff, immigrant workers also contribute more to the trust fund that supports Medicare than they receive from it, making their presence in the American workforce vial to operators’ both top and bottom lines.

That’s the conclusion of Cambridge Health Alliance physician Leah Zallman, whose work on the role of immigrants in macro-level medical policy has spanned multiple data analyses — including a new dive into the proportions of naturalized citizens, documented immigrants, and unauthorized workers in the long-term care workforce.

Nearly 3.3 million immigrants worked in the health care sector in 2017, or about 18.2% of the total workforce, according to a study published Monday in the June edition of the journal Health Affairs. That’s higher than the overall share of immigrants of in the U.S. population, which sits at around 15.5%.

Among non-medical employees at nursing homes — including maintenance staff, housekeeping, and construction workers — a full 30.3% were non-U.S. born, with about 13.1% having an unauthorized immigration status.

Zallman — who is affiliated with Harvard Medical School — and her team also took a new look into the population of immigrants in more non-formal care settings.

“A lot of our elderly and disabled are living in assisted living and hiring people privately, and living in group homes where there’s no nursing — but there are privately hired direct care workers,” she said. “We really wanted to accurately reflect them by including that non-formal component, non-formal sector.”

Of the 27.5% of direct care workers who came to the United States from other countries, about 25.7% work in those non-formal settings, compared with 24.2% in nursing homes and 31.1% employed at home health agencies.

As in many other discussions of the topic, Zallman and her team expressed great concerns over current immigration policy, which includes significant anti-immigrant rhetoric from the president and other top officials — as well as a shift toward preferring highly educated immigrants who would likely not choose to work in the health care setting.

“A lot of the policies right now are aimed at reducing poor immigrants coming into this country, and a lot of these roles, as you know, are not high-paying, high-skilled roles,” Zallman said. “And they’re not going to be filled by the highly educated, affluent immigrants that are increasingly going to become a part of the face of immigration under these current policies.”

This will only become more of a problem as the baby boom generation ages and the population of younger, native-born care workers does not keep up with the demand: Zallman’s team cited research from the Health Resources and Services Administration finding that 34% more direct care workers will be needed over the next decade, or an increase of 650,000 new jobs.

But it isn’t simply a matter of finding qualified candidates to fill open positions; a vital immigrant workforce is necessary for the health of the Medicare Trust Fund, which pays for Medicare Part A services. In 2009, according to another study Zallman conducted in 2016, immigrants represented 14.7% of the money paid into the trust fund, while only using 7.9% of the outlays — a surplus of $13.8 billion. Native-born citizens, meanwhile, took out far more than they put in, for a deficit of $30.9 million. Age demographics play a considerable role in that math, as immigrant workers tend to be younger and less likely to use Medicare services.

Even beyond the numbers game, Zallman emphasized that a climate in which immigrants are welcomed and valued is essential to ensuring quality care in nursing homes.

“General anti-immigrant rhetoric and policies that are meant to induce fear in immigrants — obviously, that’s going to have effects on the wellbeing of the population that is ensuring the wellbeing of our elderly and disabled,” she said.