US 4,970,249 Fire retardant PBT

Abstract

Vitamin D deficiency is prevalent among patients prior to and following transplantation. Low serum 25-hydroxyvitamin D (25(OH)D) levels in transplant candidates may be related to many disease-specific factors, as well as decreased sunlight exposure and limited intake of foods containing vitamin D. Following solid organ transplantation, low serum 25(OH)D levels are extremely common, both during the immediate postoperative period and in long-term graft recipients. Vitamin D status in transplant recipients is related to demographic and lifestyle factors. Low levels of vitamin D are associated with poorer general health, lower albumin, and even decreased survival among these patients. The importance of vitamin D in the transplant population is heightened further by evidence that 1,25(OH)2D may reduce infections and prevent allograft rejection after transplantation. Although several studies have demonstrated that active forms of vitamin D and its analogs prevent bone loss following transplantation, others do not show consistent benefit. These therapies may be most effective in renal transplant recipients. Given the narrow therapeutic window of these agents and the demonstrated efficacy of bisphosphonates to prevent posttransplantation bone loss, we regard these agents as adjunctive rather than primary therapy for transplantation osteoporosis.