Parathyroid Hormone Levels, Calcium-Channel Blockers, and the Dyslipidemia of Nondiabetic Hemodialysis Patients

Abstract

Background. Experimental studies have shown that increased levels of parathyroid hormone (PTH) in uremia may cause elevation of intracellular calcium, predisposing to insulin resistance and lipid metabolism abnormalities. Administration of calcium-channel blockers (CCBs) in these models protects against the development of lipid profile abnormalities. This study evaluates the combined effect of intact PTH (iPTH) levels and administration of CCB on the lipid profiles of nondiabetichemodialysis patients. Methods. One hundred and eight nondiabetic hemodialysis patients were studied for 6 months. The population was divided into four groups, according to iPTH levels and administration of CCB: (A) iPTH < 70 pg/mL, administration of CCB (n = 16), (B) iPTH> 300 pg/mL without administration of CCB (n = 43), (C) iPTH < 70 pg/mL without CCB administration (n = 19), and (D) iPTH> 300 pg/mL with CCB administration (n = 30). Serum concentrations of total cholesterol, high-density lipoprotein (HDL), triglycerides, and albumin were measured on a monthly basis. Results. All results are shown as mean ± SE. Total cholesterol values (in mg/dL) were for group (A) 186 ± 4, for group (B) 205 ± 3, for group (C) 200 ± 3, and for group (D) 203 ± 4 [p NS between (C) and (D), p < .05 for all other comparisons]. Triglycerides values (in mg/dL) were for group (A) 171 ± 9, for group (B) 199 ± 6, for group (C) 190 ± 6, and for group (D) 191 ± 9 (p NS for all comparisons). HDL values (in mg/dL) were for group (A) 43.8 ± 1, for group (B) 35.8 ± 1, for group (C) 38.3 ± 0.7, and for group (D) 37.2 ± 0.7 mg/dL [p NS between (C) and (D), p < .001 for all other comparisons]. Low-density lipoprotein values (in mg/dL) were for group (A) 107.6 ± 4.4, for group (B) 149.3 ± 2.5, for group (C) 131.2 ± 2.9, and for group (D) 126.8 ± 4.1 [p NS between (C) and (D), p < .001 for all other comparisons]. Atherogenic index values, calculated as [triglycerides/HDL] ratio, were for group (A) 4.6 ± 0.04 , for group (B) 6.2 ± 0.04 , for group (C) 4.9 ± 0.03, and for group (D) 5.9 ± 0.03 [p NS between (C) and (D), p < .004 for all other comparisons]. Conclusion. In nondiabetic hemodialysis patients, lipid profile abnormalities often accompany high levels of iPTH. The decrease in iPTH and/or the administration of CCB are accompanied by significant improvements in the main lipid profiles, including the atherogenic index.