The Effect of Long-Term Cholecalciferol Supplementation on Vascular Calcification in Chronic Kidney Disease Patients With Hypovitaminosis D.

OBJECTIVE: The role of vitamin D supplementation on vascular calcification (VC) in patients with chronic kidney disease (CKD) is controversial. The objective of this study was to evaluate the effects of long-term cholecalciferol supplementation on VC in nondialysis patients with CKD stages 3-4 with hypovitaminosis D. DESIGN AND METHODS: Eighty patients aged 18-85 years with creatinine clearance between 15 and 60 mL/min/1.73 m2 and serum 25(OH)D level < 30 ng/mL were enrolled in a 18-month prospective study. Individuals with vitamin D insufficiency (25-hydroxyvitamin D [25(OH)D] level between 16 and 29 ng/mL) were included in a randomized, double-blind, two-arm study to receive cholecalciferol or placebo. Patients with vitamin D deficiency [25(OH)D < 15 ng/mL] were included in an observational study and mandatorily received cholecalciferol. The coronary artery calcium score was obtained by multislice computed tomography at baseline and the 18th month. RESULTS: During the study, VC did not change in the treated insufficient group (418 [81-611] to 364 [232-817] AU, P = 0.25) but increased in the placebo group (118 [37-421] to 199 [49-490] AU, P = 0.01). The calcium score change was inversely correlated with 25(OH)D change (r = -0.45; P = 0.037) in the treated insufficient group but not in the placebo group. Renal function did not change in the insufficient, treated, and placebo groups. In multivariate analysis, there was no difference in VC progression between the treated and placebo insufficient groups (interaction P = 0.92). In the deficient group, VC progressed (265 [84-733] to 333 [157-745] AU; P = 0.006) and renal function declined (33 [26-43] to 23 [17-49] mL/min/1.73 m2; P = 0.04). The calcium score change was inversely correlated with cholecalciferol cumulative doses (r = -0.41; P = 0.048) and kidney function change (r = -0.43; P = 0.033) but not with 25(OH)D change (r = -0.08; P = 0.69). CONCLUSION: Vitamin D supplementation did not attenuate VC progression in CKD patients with hypovitaminosis D. CONCLUSION: Vitamin D supplementation did not attenuate VC progression in CKD patients with hypovitaminosis D.

Cholecalciferol supplementation in chronic kidney disease: restoration of vitamin D status and impact on parathyroid hormone.

BACKGROUND/AIMS: Hypovitaminosis D is highly prevalent among patients with chronic kidney disease (CKD) and has been associated with poor outcome. We aimed to test the effect of a protocol of cholecalciferol supplementation on the restoration of vitamin D status and on parathyroid hormone (PTH) levels in patients with CKD. METHODS: This was a prospective interventional study of 6 months. Forty-five CKD patients (stages 3 and 4) with 25-hydroxyvitamin D deficiency [25(OH)D <15 ng/ml] were included. Patients received a weekly dose of 50,000 IU of cholecalciferol during 3 months, and 50,000 IU/month thereafter for those who had achieved 25(OH)D ≥30 ng/ml. RESULTS: At 3 months, 78% of the patients restored their vitamin D status. At 6 months, only 43% of those patients maintained adequate vitamin D status. PTH decreased at 3 months (p = 0.02) but returned to baseline levels after 6 months. Fibroblast growth factor 23 increased at 3 months (p = 0.001) and returned to initial levels at 6 months. No changes were found in serum 1,25(OH)(2)D, ionized calcium and phosphorus. CONCLUSIONS: A weekly dose of 50,000 IU of cholecalciferol for 3 months restored the vitamin D status of most patients and led to a reduction in PTH. The monthly dose of 50,000 IU appears not to be sufficient to maintain the levels of 25(OH)D.

Variant of adynamic bone disease in hemodialysis patients: fact or fiction?

BACKGROUND: Adynamic bone disease is a type of renal osteodystrophy characterized by low bone turnover and paucity of bone cells. It was proposed that a new type of this disease featuring high osteoclastic resorption without parathyroid hormone stimulus and designated adynamic bone disease variant occurs in hemodialysis patients. The present study is designed to evaluate the frequency and characteristics of both diseases in a large series of bone biopsy specimens. METHODS: We reviewed 1,160 bone biopsy specimens from hemodialysis patients. Specimens in which adynamic bone disease was diagnosed were selected and categorized as classic or variant based on osteoclastic surface. RESULTS: In 218 bone biopsy specimens (18.8%), adynamic bone disease was identified, whereas the variant form was identified in 35 specimens (38.8%). Biopsy specimens categorized as the variant form were from patients who were younger and had greater phosphorus and parathyroid hormone levels. Histologically, the variant form presented greater osteoid volume, fibrosis volume, osteoid surface, osteoblast surface, and eroded surface. Similarly, values for all dynamic parameters were greater in the variant group. Osteoclastic surface correlated with phosphorus level, parathyroid hormone level, and osteoblast surface. Age and osteoblast surface were identified as independent determinants of the variant form. CONCLUSION: Adynamic bone disease variant seems to occur in younger hemodialysis patients with greater levels of parathyroid hormone, which acts on cell-covered bone surfaces. It probably is a transitional phase from low- to high-turnover status, rather than a true entity within the spectrum of renal osteodystrophy.

Serum ferritin level remains a reliable marker of bone marrow iron stores evaluated by histomorphometry in hemodialysis patients.

BACKGROUND AND OBJECTIVES: As well as being a marker of body iron stores, serum ferritin (sFerritin) has also been shown to be a marker of inflammation in hemodialysis (HD) patients. The aim of this study was to analyze whether sFerritin is a reliable marker of the iron stores present in bone marrow of HD patients. DESIGN: Histomorphometric analysis of stored transiliac bone biopsies was used to assess iron stores by determining the number of iron-stained cells per square millimeter of bone marrow. RESULTS: In 96 patients, the laboratory parameters were hemoglobin = 11.3 +/- 1.6 g/dl, hematocrit = 34.3 +/- 5%, sFerritin = 609 +/- 305 ng/ml, transferrin saturation = 32.7 +/- 22.5%, and C-reactive protein (CRP) = 0.9 +/- 1.4 mg/dl. sFerritin correlated significantly with CRP, bone marrow iron, and time on HD treatment (P = 0.006, 0.001, and 0.048, respectively). The independent determinants of sFerritin were CRP (beta-coef = 0.26; 95% CI = 24.6 to 132.3) and bone marrow iron (beta-coef = 0.32; 95% CI = 0.54 to 2.09). Bone marrow iron was higher in patients with sFerritin >500 ng/ml than in those with sFerritin < or =500 ng/ml. In the group of patients with sFerritin < or =500 ng/ml, the independent determinant of sFerritin was bone marrow iron (beta-coef = 0.48, 95% CI = 0.48 to 1.78), but in the group of patients with sFerritin >500 ng/ml, no independent determinant of sFerritin was found. CONCLUSIONS: sFerritin adequately reflects iron stores in bone marrow of HD patients.

Gestação e atividade física: manutenção do programa de exercícios durante a gravidez / Pregnancy and physical activity: maintenance program of exercises during pregnancy

A conscientização sobre a importância dos exercícios para assegurar boas condições físicas e mentais faz crescer o número de praticantes de atividade física em todas as faixas-etárias e populações. Os exercícios têm sido bastante procurados pelo sexo feminino para prevenção de doenças, como garantia de longevidade e para melhora da qualidade de vida. Os benefícios da atividade física só são significativos quando essa é praticada de forma regular, contínua e ao longo da vida. Por isso, é comum encontrar mulheres grávidas ou com planos de engravidar que desejam se manter ativas durante esse período. Ainda existem muitas dúvidas a respeito dos benefícios e riscos da prática de exercícios durante a gestação. O objetivo do presente estudo é responder algumas dessas questões através de um levantamento científico sobre os aspectos fisiológicos da gravidez e adaptações que a mulher grávida apresenta ao exercício físico além de fornecer orientação para as gestantes sobre benefícios para mãe e para o bebê da manutenção dos exercícios nessa fase, cuidados necessários e pontos de alerta para uma prática de atividade física segura na gestação.

The awareness of the importance of exercises practice to ensure good physical and mental conditions have increased the number of practicing of physical activity in all ages and populations. The exercises activities have been demanded by women for disease prevention, for a guarantee of longevity and for improve the quality of life. The benefits of physical activity are only meaningful when is practiced on a regular and continuous way along all the life. Therefore, it is common to find women who are pregnant or planning to be pregnant who wish to continue with exercises activities during this period.However, there are still many doubts about the benefits and risks of physical exercises during pregnancy. The objective of this work is to answer some of these issues through a scientific survey of the physiological aspects of pregnancy and the modification that pregnant women presents to physical exercise. In addition, this paper provides guidance to the pregnant women showing the benefits of exercise on this phase for her and for the baby, and also showing the points of care for a safe physical activity.