Systemic inflammation in patients with atherosclerotic cardiovascular and chronic kidney disease in Spain: a population-based study using electronic medical records from a primary care database
Authors: Pesce G , Khachatryan A , Lopez Ledesma B , Gusto G , Vukmirica J , Scheffer Apecechea N , Cases A 
Published: October 2024

Abstract

Background
Systemic inflammation (SI) is recognized as a critical driver of atherosclerotic cardiovascular disease (ASCVD), and it is frequently observed in ASCVD patients with comorbid chronic kidney disease (CKD). Elevated C-reactive protein (CRP) levels, a common biomarker for SI, have been associated with poor prognosis in ASCVD and CKD patients, increased risk of major adverse cardiovascular events and renal disease progression, as well as greater mortality.

Purpose
To estimate the prevalence of SI in patients with ASCVD in Spain overall and by CKD status, and to describe patients’ clinical characteristics.

Methods
In this population-based observational study, data from THIN Spain, a database of electronic medical records from a large network of general practitioners, were used to identify adult patients with a diagnosis code of ASCVD (atherosclerotic coronary or cerebrovascular event, peripheral arterial disease, or other atherosclerotic vascular event) and ≥1 eligible CRP measurement between January 1st 2014 to July 31st 2023 (latest data available at time of data extraction).[Figure] SI was defined as CRP ≥ 2mg/L. Point prevalence of SI at the end of the study (among patients alive with ≥1 CRP in the prior 18 months) and the proportion of patients with evidence of SI during the study period (2014-2023) were estimated overall and by CKD status (defined as CKD stage 3+, or eGFR &lt;60 mL/min/1.73m², or urinary albumin-to-creatinine ratio ≥30 mg/g). Patients’ comorbidities (defined using primary care diagnoses), and laboratory values were reported by SI status at first CRP measurement during the study period.

Results
Among 76,423 patients with ASCVD diagnosis, 15,798 patients (20.7%) were included in the study (mean age: 71.1 years; 43% females), of whom 5,111 (34%) had CKD at first eligible CRP (n=975 with unknown CKD status). Mean CRP in ASCVD patients with CKD was 24% higher than in those without CKD (4.36 vs 3.53 mg/L, p&lt;0.001). The proportion of ASCVD patients with SI at first CRP measurement was 58% overall (65% among CKD patients; 55% among patients without CKD; p&lt;0.001). The point prevalence of SI at the end of the study was 56% among ASCVD patients overall (62% among CKD patients; 52% among patients without CKD; p&lt;0.001), while 64% of ASCVD patients had evidence of SI at any time during the study period (72% among CKD patients; 59% among patients without CKD; p&lt;0.001). Compared to ASCVD patients without SI, higher proportion of SI patients were smokers and with comorbidities. Also, ASCVD patients with SI had lower baseline eGFR levels and higher levels of LDL-C and triglycerides than ASCVD patients without SI.[Table]

Conclusions
SI prevalence is high among patients with ASCVD in Spain, especially among patients with comorbid CKD. Strategies to target SI may have beneficial effects in prevention of cardiovascular events and mortality in ASCVD patients.