An HHS spokesperson did not respond to a request for comment.<\/p>\n
The study used artificial intelligence to comb through electronic medical records of patients at 58 hospitals in four regions of the country: New England, Southeast Texas, Southern California, and Western Pennsylvania. The hospitals in New England included the two flagship hospitals of MGB, Massachusetts General Hospital and Brigham and Women\u2019s Hospital.<\/p>\n
Deploying a newly developed algorithm, the researchers hunted for chronic conditions<\/a> that were likely related to long COVID but might not have led to that diagnosis. Those conditions, which had no other apparent explanation in patients\u2019 medical histories, included sudden onset of prediabetes, heart problems, neurological disorders, persistent fatigue, and chronic pain.<\/p>\n \u201cThere\u2019s a good possibility the patients themselves didn\u2019t know this condition could be long COVID,\u201d said Hossein Estiri<\/a>, director of the Clinical Augmented Intelligence Group at MGH. He was the corresponding author on the study published Wednesday in the journal JAMA Network Open.<\/p>\n Health care systems have a federally approved code for a diagnosis of long COVID. But Estiri said that doctors use it in less than 7 percent of cases because symptoms of the disorder vary widely and long COVID has no treatment.<\/p>\n \u201cIf you go to the doctor with chronic pain, it doesn\u2019t really matter to the doctor if the pain is COVID-induced,\u201d said Estiri, an associate professor of medicine at Harvard Medical School. \u201cThey just try to treat the chronic pain.\u201d<\/p>\n The Centers for Disease Control and Prevention, which is part of HHS, defines long COVID as a chronic condition that occurs after infection with the virus that causes COVID-19 and is present for at least three months. Long COVID includes a wide range of symptoms that may improve, worsen, or persist.<\/p>\n Although many people associate long COVID with the waves of infections that occurred early in the pandemic, the researchers found that cases of the chronic condition increased through mid-2025 in all four regions that they studied \u2014 and are likely still increasing.<\/p>\n Estiri was the senior author of another AI-powered study of long COVID, in 2024, that found an even higher prevalence of long COVID \u2014 one in four Americans. Estiri said that study used a broader definition of the disorder, when the scientific understanding of long COVID was less advanced, and only examined the electronic medical records of MGB patients.<\/p>\n