2153The relation between systemic inflammation and incident cancer in patients with stable cardiovascular disease; a cohort study

Abstract

Abstract Background Chronic systemic low-grade inflammation, measured by elevated plasma concentrations of high sensitive C-reactive Protein (CRP), is a risk factor for cardiovascular disease (CVD). There is evidence that systemic low-grade inflammation is also related to a higher risk of cancer. Purpose In the present prospective cohort study the relation between systemic low-grade inflammation and risk of cancer was evaluated in patients with clinically manifest vascular disease. Methods In total 7178 patients from the SMART cohort with manifest cardiovascular disease and plasma CRP levels ≤10 mg/L were included. Data of the cohort were linked to the Dutch national cancer registry. Cox regression models were fitted to study the relation between CRP and incident cardiovascular disease as well as incident cancer. Cancer types were classified according to anatomical location of origin, as well as histopathological subtype, irrespective of their anatomical location of origin. To adjust for potential confounding, age, sex, smoking status, packyears of smoking, and body mass index were added to the models, and additional cardiovascular risk factors, including diabetes mellitus, and systolic blood pressure. Results After a median follow-up time of 8.3 years (interquartile range 4.6–12.3) 1289 recurrent cardiovascular events (myocardial infarction, stroke, or vascular mortality) and 1072 incident cancer diagnoses were observed. CRP level was related to recurrent cardiovascular disease risk (HR 1.57; 95% CI 1.35–1.82) (Figure 1A), as well as risk of CVD and/or cancer (HR 1.45; 95% CI 1.29–1.62) (Figure 1B) comparing the third tertile of CRP to the first tertile. CRP concentration was related to total cancer risk (HR 1.33; 95% CI 1.13–1.55 for the third tertile of CRP compared to the first tertile) (Figure 1C). Especially incident lung cancer, independent of histopathological subtype, was related to CRP level (HR 2.64; 95% CI 1.77–3.93 for the third tertile of CRP compared to the first) (Figure 1D). No effect modification by smoking status or years of smoking cessation was observed of the relation between CRP and lung cancer (p-values for interaction >0.05). Incidence of epithelial neoplasms and especially squamous cell neoplasms were related to CRP concentration, irrespective of their anatomical location of origin (HR 1.17; 95% CI 1.08–1.27, and HR 1.11; 95% CI 1.02–1.20 for 1 mg/L higher CRP level respectively). Sensitivity analyses accounting for reverse causality by excluding patients with a cancer diagnosis within 1 and within 2 years of follow up showed similar results. Kaplan Meier curves per CRP tertile Conclusion Chronic systemic low-grade inflammation, measured by plasma CRP levels ≤10mg/L, is a risk factor for incident cancer, markedly lung cancer, independent of smoking status, in patients with stable cardiovascular disease.