Researchers relying partly on reports of Alabamians experiencing long COVID have created four new subcategories of the disease to help doctors route patients toward the best treatments.

The study was published last month in Nature Medicine. Researchers relied on data from Alabama, Florida, Georgia and New York. According to the Centers for Disease Control, Alabama has the second-highest rate of long COVID in the country, at 12.1 percent of COVID-19 cases, following Kentucky at 12.7 percent.

Dr. Scott Harris, state health officer, said Alabamians are at higher risk for long COVID because of preexisting health conditions and low vaccination rates. “At baseline Alabama has a big burden of chronic disease,” he said.

The study identified the most prevalent subtype of long COVID, experienced by about 34 percent of patients, as including heart, kidney and circulation problems and tended to include older, male patients.

A second common combination of post-COVID symptoms, impacting about 33 percent of people studied with long COVID, included respiratory, sleep, anxiety, headache and chest pain. This group had a lower rate of hospitalization than the first, according to the study, and were more likely to test positive for COVID during a later surge of the pandemic, between November of 2020 and November of 2021.

“These (subtypes) can inform effective hypotheses generation for biological mechanistic studies of long-COVID, as well as treatment development strategies for long COVID,” said study author Dr. Fei Wang of Cornell University.

The third subtype included patients with musculoskeletal symptoms, accounting for 23 percent of patients. Digestive and respiratory symptoms together were found in about 10 percent of people studied, making up the fourth symptom grouping.

Dr. Nathan Erdman, a UAB professor helping to run the school’s long COVID clinic, which does treatment and research, said creating subcategories for COVID helps doctors give focused treatment. Already UAB is sending people with cardiac symptoms to cardiologists and those with skin or asthma to related specialists, he said.

UAB is one of 15 institutions in a large NIH study focused on better understanding what long COVID is and who gets it. The school is also starting clinical trials this month on whether Paxlovid, an antiviral drug used to treat acute COVID, could be helpful to relieve symptoms for some people with long COVID.

“There appears to be evidence that in at least some of the people who have long COVID, the virus doesn’t fully go away. This study is looking at, does an antiviral help deal with symptoms or resolution of the syndrome?” said Erdman.

Dr. Harris, the state health officer, said Alabama has a lack of data on long COVID, and there still isn’t a clear picture of how many people are impacted or how.

“With any kind of new disease, there’s probably a lot of frustration among the people who are the first recognized cases of it until the medical community as a whole develops more experience and expertise,” he said.