Serum levels of 1,25-dihydroxyvitamin D, 24,25-dihydroxyvitamin D, and 25-hydroxyvitamin D in nondialyzed patients with chronic renal failure

Serum levels of 1,25-dihydroxyvitamin D, 24,25-dihydroxyvitamin D, and 25-hydroxyvitamin D in nondialyzed patients with chronic renal failure.BackgroundIn patients with chronic renal failure (CRF), abnormalities in vitamin D metabolism are known to be present, and several factors could contribute to the abnormalities.MethodsWe measured serum levels of three vitamin D metabolites, 1,25(OH)2D, 24,25(OH)2D and 25(OH)D, and analyzed factors affecting their levels in 76 nondialyzed patients with CRF (serum creatinine> 1.6 and < 9.0 mg/dl), 37 of whom had diabetes mellitus (DM-CRF) and 39 of whom were nondiabetic (nonDM-CRF).ResultsSerum levels of 1,25(OH)2D were positively correlated with estimated creatinine clearance (CCr; r = 0.429; P < 0.0001), and levels of 24,25(OH)2D were weakly correlated with CCr (r = 0.252, P < 0.05); no correlation was noted for 25(OH)D. Serum levels of all three vitamin D metabolites were significantly and positively correlated with serum albumin. Although there were no significant differences in age, sex, estimated CCr, calcium and phosphate between DM-CRF and nonDM-CRF, all three vitamin D metabolites were significantly lower in DM-CRF than in nonDM-CRF. To analyze factors influencing vitamin D metabolite levels, we performed multiple regression analyses. Serum 25(OH)D levels were significantly and independently associated with serum albumin, presence of DM and serum phosphate (R2 = 0.599; P < 0.0001). 24,25(OH)2D levels were significantly and strongly associated with 25(OH)D (β; = 0.772; R2 = 0.446; P < 0.0001). Serum 1,25(OH)2D levels were significantly associated only with estimated CCr (R2 = 0.409; P < 0.0001).ConclusionsThese results suggest that hypoalbuminemia and the presence of DM independently affect serum 25(OH)D levels, probably via diabetic nephropathy and poor nutritional status associated with diabetes, and that 25(OH)D is actively catalyzed to 24,25(OH)2D in CRF, probably largely via extrarenal 24-hydroxylase. Serum levels of 1,25(OH)2D were significantly affected by the degree of renal failure. Thus, this study indicates that patients with CRF, particularly those with DM, should receive supplements containing the active form of vitamin D prior to dialysis

Impact of diabetes on sarcopenia and mortality in patients undergoing hemodialysis

Abstract Background Sarcopenia has become a serious disorder in modern society. Chronic kidney disease requiring dialysis and diabetes are some of the disorders that accelerate the onset and progression of sarcopenia. We, therefore, investigated the prevalence of sarcopenia in patients undergoing hemodialysis (HD) and confirmed the impact of diabetes mellitus (DM) on this population. Methods This study included 308 patients whose muscle strength and mass had been evaluated using handgrip strength and dual-energy X-ray absorptiometry, respectively. Sarcopenia was defined according to the criteria established by the Asian Working Group on Sarcopenia. In addition, this cohort had been followed up for 9 years. Results The prevalence of sarcopenia was 40% (37% in males and 45% in females) with gender differences being insignificant (p = 0.237). The DM morbidity rate was significantly higher in those with sarcopenia than in those without sarcopenia (41% vs. 27%, p = 0.015). Multivariate regression analyses showed that the presence of DM was an independent contributor to sarcopenia in patients undergoing HD (odds ratio 3.11; 95% confidence interval 1.63–5.93; p <  0.001). During the follow-up of 76 ± 35 months, 100 patients died. Patients with sarcopenia demonstrated significantly higher rates of all-cause mortality than those without sarcopenia (p <  0.001 using the log-rank test). Multivariate Cox proportional hazards analyses revealed that the presence of DM was significantly associated with higher all-cause mortality (adjusted hazard ratio: 2.39; 95% confidence interval 1.51–3.81; p <  0.001). Conclusions The prevalence of sarcopenia among this cohort of patients undergoing HD was determined to be 40%. Moreover, the presence of DM was an independent contributor to sarcopenia and an independent predictor of all-cause mortality in this population

Significant Association Between Bone-Specific Alkaline Phosphatase and Vascular Calcification of the Hand Arteries in Male Hemodialysis Patients

Background/Aims: Bone-specific alkaline phosphatase (BAP) hydrolyzes pyrophosphate, which inhibits vascular calcification. We examined association between serum BAP and vascular calcification of male hemodialysis patients. Methods: Hand roentgenography of 167 male maintenance hemodialysis patients was conducted, and visible vascular calcification of the hand arteries was evaluated. Serum levels of 3 bone formation markers (BAP, osteocalcin, and N-terminal propeptide of type I collagen) and 2 bone resorption markers (C-terminal telopeptide of type I collagen, and cross-linked N-telopeptide of type I collagen) were measured, along with serum intact parathyroid hormone (PTH). Results: Of 167 patients, visible vascular calcification was seen in 37 patients. Among the bone formation and resorption markers, serum BAP was significantly higher in patients with vascular calcification than in those without (pConclusions: Higher serum BAP, but not other bone markers, is significantly associated with the presence of vascular calcification in male hemodialysis patients