Changes in high-sensitivity C-reactive protein testing and distribution across the COVID-19 pandemic: a 17-year laboratory-based study
Jeong Su Han, Jae-Sik Jeon, Jae Kyung KimAbstract
Introduction
COVID-19 altered health care utilization and laboratory testing. We assessed changes in routine high-sensitivity C-reactive protein (hs-CRP) testing and distributions across the pandemic.
Methods
We retrospectively analyzed hs-CRP results from a tertiary-care medical center from 2007 through 2023. We included 314 106 episodes from 116 505 patients. Annual testing volume, median values, upper-tail percentiles, and threshold categories were assessed, and distributions were compared across the prepandemic (2007-2019), pandemic (2020-2022), and postpandemic (2023) periods.
Results
The hs-CRP distribution was right skewed (median, 0.050 mg/dL; 95th and 99th percentiles, 0.440 mg/dL and 1.060 mg/dL, respectively). Annual median values remained stable, but upper percentiles and the proportion of hs-CRP results 0.3 mg/dL or higher declined (annual odds ratio, 0.985 [95% CI, 0.983-0.988]). During 2020-2022, hs-CRP values below 0.1 mg/dL were more frequent and values at or above 0.3 mg/dL less frequent than before the pandemic.
Discussion
Pandemic-period differences occurred against a preexisting decline in upper-tail hs-CRP values. These findings should be interpreted in their long-term context, considering testing volume and result distributions.