Chronic Inflammation as an Overlooked Link Between Cardiovascular and Kidney Disease: A Focus on Interleukin-6 and C-Reactive Protein

The role of chronic subclinical inflammation in both chronic kidney disease (CKD) and cardiovascular disease (CVD) is well established, with the residual risk of inflammation also key to the interaction between CKD and CVD as part of cardiorenal syndrome. Inflammation, alongside oxidative stress, leads to a self-perpetuating cycle of kidney and cardiovascular damage, which contributes to worse mortality and disease outcomes in patients with CKD and CVD. Interleukin-6 and C-reactive protein (CRP), often measured as high-sensitivity CRP (hsCRP), are key inflammatory biomarkers that correlate with more severe CKD and CVD as well as with worse mortality and disease outcomes. Therefore, CRP and hsCRP are implicated as prognostic markers of residual inflammatory risk. Given these observations, clinicians could consider assessment of individuals with CKD, especially if they have CVD, for chronic inflammation, by monitoring changes in hsCRP values or other surrogate markers of inflammation. Despite current standard treatments, inflammation continues to drive disease progression in patients with CKD and CVD, making inflammatory risk an appealing target for novel therapies. This review provides an overview of the role of inflammation in patients with CKD and CVD, and the potential role of anti-inflammatory drugs to reduce residual risk in patients with these diseases.