Monocyte to HDL ratio: a novel marker of resistant hypertension in CKD patients

Background Inflammation, oxidative stress (OS), atherosclerosis and resistant hypertension (RH) are common features of chronic kidney disease (CKD) leading to a higher risk of death from cardiovascular disease. These effects seem to be modulated by impaired anti-oxidant, anti-inflammatory and reverse cholesterol transport actions of high-density lipoprotein cholesterol (HDL). HDL prevents and reverses monocyte recruitment and activation into the arterial wall and impairs endothelial adhesion molecule expression. Recently, monocyte count to HDL-cholesterol ratio (MHR) has emerged as a potential marker of inflammation and OS, demonstrating to be relevant in CKD. Our research was aimed to assess, for the first time, its reliability in RH. Methods We performed a retrospective study on 214 patients with CKD and arterial hypertension who were admitted between January and June 2019 to our Department, 72 of whom were diagnosed with RH. Results MHR appeared inversely related to eGFR (rho = - 0.163; P = 0.0172). MHR was significantly higher among RH patients compared to non-RH ones (12.39 [IQR 10.67-16.05] versus 7.30 [5.49-9.06]; P < 0.0001). Moreover, MHR was significantly different according to the number of anti-hypertensive drugs per patient in the whole study cohort (F = 46.723; P < 0.001) as well as in the non-RH group (F = 14.191; P < 0.001). Moreover, MHR positively correlates with diabetes mellitus (rho = 0.253; P = 0.0002), white blood cells (rho = 0.664; P < 0.0001) and C-reactive protein (rho = 0.563; P < 0.0001). Conclusions MHR may be a reliable biomarker due to the connection between HDL and monocytes. Our study suggests that MHR is linked with the use of multiple anti-hypertensive therapy and resistant hypertension in CKD patients, and can be a useful ratio to implement appropriate treatment strategies.