One-year follow-up of COVID-19 recoverees with impaired pulmonary function: A prospective cohort study.

Decreased diffusion capacity for carbon monoxide (DLCO) is the most prevalent pulmonary testing abnormality among COVID-19 recoverees. We prospectively followed 51 individuals with impaired DLCO at an average of ∼3 months following COVID-19 and re-examined them at one year. At follow-up, mean DLCO increased from 68.0 % to 72.6 % (p = 0.002); while 33 % of the cohort experienced a clinically significant rise (>10 points) in DLCO, only 29 % normalized their values. While DLCO change did not correlate with symptoms, lack of improvement was more prevalent among individuals with obesity. Regardless of COVID-19 severity, a substantial proportion continued to exhibit DLCO impairment at 1-year.