Renal function and markers of cardiovascular risk

Abstract Patients with chronic renal insufficiency (CRI), also at its early stages, have an elevated risk of cardiovascular disease (CVD). Many well-established risk factors of CVD co-occur in CRI, e.g. dyslipidemia and hypertension. The present studies investigated the association between renal function and selected CVD risk factors. The fractional catabolic rate of low-density lipoprotein apolipoprotein B (LDL FCR) has previously been found to be reduced in patients with severe CRI or on dialysis. This study investigated the LDL FCR in 57 patients with moderate to severe CRI and not on dialysis. Although the mean LDL FCR was comparable between the CRI patients and healthy controls, among the renal patients the LDL FCR was correlated with renal function, whereas it was significantly reduced only in patients with advanced CRI (estimated glomerular filtration rate <15 mL/min/1.73 m2). Leptin is a protein regulating food intake and energy expenditure and it is also involved in lipid metabolism. Hyperleptinaemia is a known feature of CRI patients; they are thought to be leptin resistant. The association between leptin and the lipoprotein profile was studied in 73 CRI patients with moderate to severe CRI and not on dialysis. Leptin was associated with lipid and lipoprotein concentrations in the renal patients, as in the control subjects, pointing towards a poorer lipoprotein profile with higher leptin levels. Hypertensive subjects in whom nocturnal blood pressure (BP) declines by less than 10% (non-dippers) show more organ damage than those in whom it falls by more than 10% (dippers). Here, non-dipping was found in 19% of middle-aged subjects (226 males, 234 females) evaluated with ambulatory BP monitoring. The non-dippers had significantly lower renal function as compared with the dippers, and dipping status was a significant predictor of the variation in eGFR. Furthermore, an increased risk of non-dipping was observed among subjects with only minor decreases in renal function. Carotid intima-media thickness (cIMT) can be used as a surrogate marker of early atherosclerosis. The present study investigated the association between renal function and cIMT in middle-aged subjects (247 males, 258 females). Renal function was independently associated with cIMT among males and also among postmenopausal women. The increased cIMT was seen in conjunction with mild renal impairment. In conclusion, the catabolism of LDL correlated with the renal function among CRI patients, but it was significantly reduced only in patients with advanced CRI. Leptin concentrations correlated with the lipoprotein profile in CRI patients. Among general middle-aged subjects, even a mild decrease in renal function was associated with derangements in BP regulation and with increased carotid atherosclerosis