BACKGROUND: Systemic inflammation (SI) is a risk factor for atherosclerotic cardiovascular disease (ASCVD) and is most commonly assessed by measuring levels of high-sensitivity C-reactive protein (hsCRP). OBJECTIVE: This study aimed to determine hsCRP testing rates and SI prevalence in patients with ASCVD and in a subset of patients with chronic kidney disease (CKD). METHODS: This was a retrospective, cross-sectional analysis using US-based data from the Optum® de-identified Electronic Health Record data set (Optum® EHR
1/1/2017-12/31/2021). hsCRP testing rates and SI prevalence (hsCRP ≥2 to <
10 mg/L) were evaluated by calendar year. Demographics, comorbidities, and treatment patterns were compared between patients with ASCVD, ASCVD + CKD, and ASCVD + stage 3/4 CKD, with and without SI. RESULTS: 1,658,476 patients with ASCVD were eligible for study inclusion. Per calendar year, 44.9 %-68.8 % and 14.9 %-18.9 % of patients had any CKD and stage 3/4 CKD, respectively. hsCRP testing was performed in 0.87 %-0.98 % (ASCVD), 0.90 %-1.17 % (ASCVD + CKD), and 0.99 %-1.41 % (ASCVD + stage 3/4 CKD) of patients. SI was present in 37.16 %-38.62 % (ASCVD), 40.61 %-44.44 % (ASCVD + CKD), and 49.44 %-53.92 % (ASCVD + stage 3/4 CKD) of tested patients. Among those with SI, patients with CKD had a greater comorbidity burden than those without. CONCLUSION: While rates of hsCRP testing were low in patients with ASCVD, the prevalence of SI was high in hsCRP-tested patients with ASCVD, irrespective of CKD presence or severity. Given the low rate of testing, patients with SI may not be identified and treated.