Levels of circulating microparticles in patients with chronic cardiorenal disease

Aim: Cardiac and renal diseases are common disorders that frequently coexist. We tested the hypothesis that the levels of circulating endothelial-derived apoptotic microparticles (EDA-MPs; CD31⁺CD42b⁻AN⁻V⁺) and platelet-derived apoptotic microparticles (PDA-MPs; CD31⁺CD42b⁺AN⁻V⁺) are useful biomarkers for predicting the presence of cardiorenal disease (CRD). Methods: A total of 68 patients with chronic kidney disease (CKD) and angina pectoris (CKD-AP) undergoing cardiac catheterization were prospectively enrolled into group 1, 10 patients with coronary artery disease (CAD) without CKD were enrolled into group 2 (CAD⁺CKD⁻) and 10 patients without CAD and CKD were enrolled into group 3 (CAD⁻CKD⁻). Results: The serum creatinine levels were significantly higher, whereas the estimated glomerular filtration rates (eGFRs) were significantly lower, in group 1 than in the other two groups (all p<0.02). The circulating levels of EDA-MPs and PDA-MPs did not differ between the patients with and without CKD (all p>0.2). However, the circulating levels of EDA-MPs and PDA-MPs were significantly higher in group 2 than in groups 1 and 3 (all p<0.03). In addition, differences were noted in the circulating EDA-MP and PDA-MP levels between groups 1 and 3, although without statistical significance (all p>0.09). Meanwhile, among the CKD patients, the subgroup analysis showed that the levels of MPs were significantly higher in those with CAD than in those without (all p=0.001), while a multivariate analysis demonstrated that CAD was the only factor independently predictive of high levels of circulating EDA-MPs and PDA-MPs (p=0.033). Conclusions: The link with increased circulating levels of MPs is more consistent in patients with CAD than in those with CKD.