Association between elevated C-reactive protein and mortality, healthcare resource utilization and costs in patients with atherosclerotic cardiovascular disease and/or chronic kidney disease

Abstract Background and Aims Atherosclerotic cardiovascular disease (ASCVD) and chronic kidney disease (CKD) impact health and healthcare systems. Inflammation is a potential modifiable risk factor for both conditions. The case for evaluating the modification of inflammation in these conditions could be strengthened by evidence that systemic inflammation (C-reactive protein [CRP] ≥2 mg/L) was associated with a considerable health burden. Methods A retrospective observational cohort study of 179 261 individuals in mutually exclusive cohorts (ASCVD only, CKD stages 3–4 only, ASCVD+CKD stages 3–4) and a reference cohort (no ASCVD or CKD) with ≥1 CRP measurement after diagnosis. Outcomes included all-cause mortality, healthcare resource utilization (HCRU) and direct healthcare costs. Results CKD stages 3–4, ASCVD only and ASCVD+CKD stages 3–4 cohorts compared with the reference cohort were associated with increasing all-cause mortality (death/100 000 person-years) of 1637, 2090, 5163 and 946, respectively. HCRU events per person per year (PPPY) and mean direct costs PPPY were 20.4, 21.4, 34.2 and 8.2 and £2593, £3098, £6810 and £1144, respectively. Within cohorts, all-cause mortality increased progressively across CRP quartiles (Q) and was highest in Q4 among the ASCVD+CKD stages 3–4 cohort, with a hazard ratio (Q4 vs Q1) of 2.75 in this cohort compared with 1.22 in the reference cohort. Conclusions While the clinical impact of targeting inflammation is being evaluated in ongoing trials, this real-world study demonstrates that assessing inflammation in patients with ASCVD and CKD stages 3–4 can help to identify a population with a high healthcare burden.