Long-term exposure to PM2.5 increases risk of long COVID in young adults: The Lancet

Long COVID is a condition where individuals experience persistent symptoms after being infected with SARS-CoV-2 for two months or longer.

The study used data from the BAMSE cohort, which included 753 participants who had contracted SARS-CoV-2. Of those participants, 116 reported experiencing long COVID symptoms, which included altered sense of smell or taste, dyspnea (difficulty breathing), and fatigue.

The researchers estimated each participant's exposure to air pollution by analyzing levels of PM2.5, PM10, black carbon (BC), and nitrogen oxides (NOx) at their individual-level addresses through dispersion modeling. There were 753 participants with SARS-CoV-2 infection in total, with 116 (15.4%) reporting long COVID. The most common symptoms encountered among the participants were altered smell/taste, dyspnea, and fatigue.

The study concluded with the following findings:

1. 1.The study found that the adjusted odds ratios for PM2.5 per IQR (Interquartile range) increase were 1.28 for long COVID, 1.65 for dyspnea symptoms, and 1.29 for altered smell/taste.
2. 2.Positive associations were also found for the other air pollutants, and these associations tended to be stronger among participants with asthma and those who contracted COVID-19 in 2020 rather than in 2021.

The lead author Dr. Zhebin Yu added that “Ambient long-term PM2.5 exposure may affect the risk of long COVID in young adults, further emphasizing the importance of improving air quality. This study is significant because it provides insight into the underlying risk factors for long COVID and highlights the need for efforts to continuously improve air quality.”

The findings of this study will be important for policymakers and public health officials, who can use this information to implement policies and interventions to improve air quality and reduce the risk of long COVID. The study also emphasizes the importance of taking steps to protect oneself from exposure to air pollution, particularly for individuals who are at a higher risk of developing long COVID.

Reference:

Yu Z, Ekström S, Bellander T, et al. Ambient air pollution exposure linked to long COVID among young adults: a nested survey in a population-based cohort in Sweden. The Lancet Regional Health - Europe. 2023; 100608 doi: https://doi.org/10. 1016/j.lanepe.2023. 100608