Effect of low molecular weight heparin on bone metabolism and hyperlipidemia in patients on maintenance hemodialysis

The effect of low molecular weight heparin (LMWH) on serum lipid profile in hemodialysis remains controversial and its effect on bone metabolism has n ot been studied. A crossover study was conducted in 40 patients on stable h emodialysis using unfractionated heparin (UFH) for more than 24 months. The se patients were then treated with a LMWH (nadroparin-Ca) for 8 months duri ng hemodialysis and subsequently switched back to UFH for 12 months. Serum lipid profile, biochemical markers for bone metabolism, and bone densitomet ry (BMD) were monitored at four-month intervals while all medications remai ned unchanged. Cholesterol (TC), triglyceride (TG), low-density lipoprotein-cholesterol (L DL-C), lipoprotein(a) (Lp(a)), apolipoprotein B (Apo B) were raised in 35%, 29%, 12%, 24% and 24% of patients respectively. High-density lipoprotein-c holesterol (HDL-C) and apolipoprotein A1 (Apo A-1) were reduced in 47% and 9% of patients. Bone-specific alkaline phosphatase (BALP) and intact osteoc alcin (OSC), both reflecting osteoblastic activity, were raised in 65% and 94% of patients. Tartrate-resistant acid phosphatase (TRACP) reflecting ost eoclastic activity and parathyroid hormone (PTH) were elevated in 35% and 8 8% of patients. Following LMWH treatment TC, Tg, Lp(a) and Apo B were reduc ed by 7%, 30%, 21% and 10% respectively (p<0.05 or <0.01) while Apo A-1 wer e raised by 7% (p<0.01). Simultaneously, TRACP was reduced by 13% (p<0.05). These biochemical changes were detected soon after 4 months of LMWH admini stration, Although BMD values in our patients were lower than those of age- matched normal subjects, significant changes were not observed with LMWH tr eatment. After switching back to UFH for hemodialysis, these biochemical in dices reverted to previous values during UFH treatment with a significant h igher level in TC and Apo B while serum Apo A-1 remained elevated. Our stud y suggests LMWH may partially alleviate hyperlipidemia and, perhaps, osteop orosis associated with UFH administration in patients on maintenance hemodi alysis.