More than 50% of patients experiencing long COVID-19 did not improve after 18 months, according to new study findings that included more than 800 patients.
The research was published Oct. 31 in the International Journal of Infectious Diseases, and is based on an analysis of 806 patients referred to a long COVID-19 clinic in Denmark. Referred patients had persistent symptoms at least 12 weeks after the onset of COVID-19. Overall, 70% of patients were female, with a median age of 48.
Researchers used the results of a symptom questionnaire to assess whether patients improved over a 1.5 year follow-up period. Patients were given standard health scores four times between enrollment and after 18 months of follow-up.
Of the 429 patients they were able to follow up with at 1.5 years, 57% "failed to improve in long COVID-19 severity" regardless of the variant they were infected with, the findings showed. There was a significant drop in median scores from the symptom questionnaires 7 to 10 months after infection, before plateauing 12 to 18 months after infection.
"We suggest the search for long COVID treatments focus on those severely affected patients to develop future new treatments, which we believe will be effective across all SARS-CoV-2 variants."