New study links COVID to fewer long-term health problems

A study published Nov. 3 in Annals of Internal Medicine found that about half of adults with long COVID experienced sustained symptom improvement within three years of infection, according to Nature World News. The research followed 1,019 adults who still had likely long COVID 12 months after their initial infection, tracking symptoms for up to three years after infection, Nature World News reported. By two years, 36.2% had sustained symptom improvement. By three years, that figure rose to 50.1%. At the three-year mark, 56.4% had substantial symptom reductions with good quality of life, and 26.9% reached complete remission, meaning they reported none of the tracked symptoms at that time, Nature World News reported.

Outlook varied heavily by symptom type. Roughly 60% of people whose illness centered on lost or changed smell and taste improved, compared with fewer than 1 in 5 of those whose symptoms spread across multiple body systems, Nature World News reported. Adjusted estimates showed improvement by three years for 59.6% of the smell-or-taste group, 54.6% of the chronic cough group, and 48.5% of the brain fog group. Patients in the palpitations group and the multisystem group did worse, with the multisystem group faring the poorest at fewer than 1 in 5 improving within three years, according to Nature World News.

Other patterns emerged: adults under 46 improved more often than older participants, and people infected during the Omicron period improved more often than those infected with earlier variants. Men and women improved at similar rates, Nature World News reported.

Harrison Reeder, a biostatistician at Massachusetts General Hospital and the study's corresponding author, said the multisystem group "might be a group where an effective intervention can make a bigger difference." He told Live Science he deliberately avoided calling participants "recovered," because symptoms can fluctuate and patient advocates raised concerns about implying permanence, Nature World News reported.

Outside experts raised questions about the scoring system. Louis Health Care System, told the Japan Times that the index gives substantial weight to smell and taste loss and chronic cough, symptoms common after COVID-19 but not central to the chronic multisystem illness he associates with long COVID, Nature World News reported. Nisreen Alwan of the University of Southampton noted that the index has not yet been independently validated in other populations, Nature World News reported.

The study did not track whether people who improved later relapsed, leaving open whether some improvements will hold beyond three years, Nature World News reported. The authors said the study was not designed to determine what causes some people to improve faster than others, Nature World News reported. The findings point to a need for placebo-controlled studies of possible treatments, with the multisystem group standing to gain the most from an effective therapy, Nature World News reported.