(HealthDay News) — Routine clinical laboratory values do not serve as biomarkers for postacute sequelae of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection (PASC), according to a study published online Aug. 13 in the Annals of Internal Medicine.
Kristine M. Erlandson, MD, from the University of Colorado Anschutz Medical Campus in Aurora, and colleagues examined clinical laboratory markers of SARS-CoV-2 and PASC. Differences in mean laboratory measures were assessed by prior infection and PASC index in propensity score-weighted linear regression models. Participants included 10,094 adults from 83 sites with or without SARS-CoV-2 infection with a study visit and laboratory measures six months after the index date.
Of the participants, 8,746 had prior SARS-CoV-2 infection and 1,348 were uninfected; 1,880 had a PASC index of 12 or higher and 3,351 had a PASC index of 0. The researchers found that participants with prior infection had a lower mean platelet count than those without known prior infection after propensity score adjustment, and they had a higher mean hemoglobin A1c (HbA1c) level and urinary albumin-creatinine ratio, with the differences of modest clinical significance. After exclusion of patients with preexisting diabetes, the difference in HbA1c levels was attenuated. No meaningful differences were seen in mean laboratory values between those with a PASC index of 12 or higher versus 0 among participants with prior infection.
“Understanding the basic biological underpinnings of persistent symptoms after SARS-CoV-2 infection will likely require a rigorous focus on investigations beyond routine clinical laboratory studies (for example, transcriptomics, proteomics, metabolomics) to identify novel biomarkers,” the authors write.
