A new study provides another reason why the coronavirus pandemic is disproportionately killing people from low-income communities: Residents in these areas often lack access to intensive care unit (ICU) beds, showing how patients’ zip code can affect whether they get lifesaving care.

Intensive care units, or critical care units, are essential to providing life support for coronavirus patients who are so sick, they must be put on ventilators so they can breathe.

Since the pandemic started, there have been shortages of ICU beds in parts of the United States, including some urban areas. But the new study from the University of Pennsylvania published Monday in the August issue of Health Affairs shows many low-income communities are particularly at risk.

“The distribution of ICU beds is uneven across the country. What was striking to me was the percentage of communities with zero ICU beds,” said Genevieve Kanter, lead author of the study and assistant professor of medicine, medical ethics, and health policy in the Perelman School of Medicine at the University of Pennsylvania.

According to the study, approximately half of the communities with the lowest median household incomes (less than $35,000) have zero ICU beds per 10,000 residents over age 50. Multiple areas in Pennsylvania face this complete lack of ICU beds, while many more communities in Pennsylvania and New Jersey have no more than a handful of ICU beds.

There are some low-income communities, especially in urban areas with major academic medical centers, that have good access to ICU beds. Philadelphia is one example. But overall, access to ICU beds is considerably better in higher-income communities, as just 3% of communities with household incomes of at least $90,000 have zero ICU beds per 10,000 residents.

In rural areas, the relationship between household income and ICU bed availability is much more pronounced compared with urban areas — as is the case in Pennsylvania. This is cause for concern as coronavirus outbreaks rise in rural areas. There are approximately 1,821 rural hospitals in the United States, according to the American Hospital Association, and approximately 1,350 of these have only 25 or fewer inpatient beds. Most of these “critical-access” hospitals are not equipped to deal with severe coronavirus cases.

“Critical access hospitals do primary care and general surgeries,” said Alan Morgan, CEO of the National Rural Health Association. “That’s what they were built for. They were not built for global pandemics and outbreaks.”

Morgan added that rural hospitals often don’t have many ICU beds — on average from one to five. These hospitals all have transfer relationships with larger institutions. For instance, if a patient needs an ICU bed, the standard protocol is to transfer the patient to the closest hospital that has one.

“That’s part of the concern we’re facing now from a rural perspective – it’s not always an option [to transfer a patient] with the volume of [coronavirus] cases, especially when urban hospitals are experiencing surges the same time rural ones are,” Morgan said.

What’s worse, the pandemic has also placed considerable financial strain on rural hospitals, with many struggling to keep normal services, like nonemergency procedures, operating. Still, low-income communities, rural and urban, have been disproportionally harmed by the coronavirus, due to factors including housing situations, occupation-related exposure risks, and use of public transportation.

“At the first level, these social conditions lead to higher infection rates,” Kanter said. “At the second level, these populations tend to have a higher prevalence of underlying, chronic conditions like hypertension and chronic obstructive pulmonary disease.”

Now researchers have identified the third level: some people who get infected and need to go to the hospital but can’t get the right level of care.

“You cannot possibly design a worse scenario than what we’re facing right now,” Morgan said. “Those most in need of care are clustered in these small towns with the fewest resources available.”

Better coordination of hospital transfers that often mean the difference between life and death for patients is needed. In a study recently published in JAMA Internal Medicine, researchers found that patients admitted to smaller hospitals were more than three times likelier to die than patients admitted to larger hospitals.

“If a patient is at a small hospital and isn’t getting better, and it doesn’t have all the resources – it makes sense to be transferred to a larger hospital,” said David Leaf, assistant professor of medicine at Brigham and Women’s Hospital and senior author of the JAMA Internal Medicine study.

But the pandemic has also made hospital transfers challenging.

“The hospitals that have capacity, they are feeling the effects of the pandemic on their bottom line,” Kanter said. “A lot of them haven’t been able to do as many elective procedures. They have little incentive to accept transfers. At a higher level, it comes down to some higher-level coordination of resources and efforts, whether at the federal, state, or local levels, to the communities that would be most affected.”