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The effects of vitamin D treatment on glycemic control, serum lipid profiles, and C-reactive protein in patients with chronic kidney disease: a systematic review and meta-analysis of randomized controlled trials. Int Urol Nephrol 2019; 51:1567-1580. [DOI: 10.1007/s11255-019-02236-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Accepted: 07/15/2019] [Indexed: 01/14/2023]
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Exebio JC, Ajabshir S, Campa A, Li T, Zarini GG, Huffman FG. The Effect of Vitamin D Supplementation on Blood Lipids in Minorities with Type 2 Diabetes. INTERNATIONAL JOURNAL OF DIABETES AND CLINICAL RESEARCH 2018; 5:093. [PMID: 31497649 PMCID: PMC6731032 DOI: 10.23937/2377-3634/1410093] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
INTRODUCTION Vitamin D deficiency and type 2 diabetes are common among Hispanics and African Americans in the US. The aim of the study was to determine the effect of supplemental vitamin D intake (4000 IU/day or 6000 IU/day of vitamin D3 over a 6-month period) on blood lipids in a sample of African Americans and Hispanics with type 2 diabetes and vitamin D insufficiency. MATERIALS AND METHODS Participants (n = 75) were recruited by community outreach. Participants in both groups were required to take either 4000 IU or 6000 IU of vitamin D (Cholecalciferol) per day given in the form of a pill in a single daily dose. Mixed model was used to compare treatment effects (4000 IU vs. 6000 IU) on the outcome variables. Bonferroni multiple comparison test was used to detect significant changes from baseline, 3 months, and 6 months. RESULTS A significant decrease in total cholesterol (from 193.88 ± 41.03 to 180.48 ± 27.53 mg/dl, P = 0.040) and triglycerides (from 201.44 ± 91.35 to 172.92 ± 76.87 mg/dl, P = 0.037) was found for the 6000 IU group at 6 months. The significance was lost after adjusting for confounders. CONCLUSION Our results suggest that the positive effect of vitamin D supplementation on lipid profile may be mediated by other cofactors related to vitamin D metabolism among Hispanic and African American participants with type 2 diabetes.
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Affiliation(s)
- Joel C Exebio
- Dietetics and Nutrition Department, Robert Stempel College of Public Health and Social Work, Florida International University, USA
- Dietetics and Nutrition Department, School of Allied Health, Keiser University, USA
| | - Sahar Ajabshir
- Dietetics and Nutrition Department, Robert Stempel College of Public Health and Social Work, Florida International University, USA
- Cellular Biology and Pharmacology Department, Herbert Wertheim College of Medicine, Florida International University, USA
| | - Adriana Campa
- Dietetics and Nutrition Department, Robert Stempel College of Public Health and Social Work, Florida International University, USA
| | - Tan Li
- Biostatistics Department, Robert Stempel College of Public Health and Social Work, Florida International University, USA
| | - Gustavo G Zarini
- Dietetics and Nutrition Department, Robert Stempel College of Public Health and Social Work, Florida International University, USA
| | - Fatma G Huffman
- Dietetics and Nutrition Department, Robert Stempel College of Public Health and Social Work, Florida International University, USA
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Spoto B, Pizzini P, Cutrupi S, Tripepi G, Curatola G, Mallamaci F, Zoccali C. Vitamin D receptor activation by paricalcitol and insulin resistance in CKD. Nutr Metab Cardiovasc Dis 2018; 28:291-297. [PMID: 29307660 DOI: 10.1016/j.numecd.2017.11.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/12/2017] [Revised: 10/26/2017] [Accepted: 11/28/2017] [Indexed: 10/18/2022]
Abstract
BACKGROUND AND AIMS The nature of the link (causal vs non-causal) between low 1,25-OH vitamin D and insulin resistance (IR) in patients with chronic kidney disease (CKD) remains elusive. We have now made a post hoc analysis of the effect of vitamin D receptor activation by paricalcitol on IR in the complete dataset of a double-blind, randomized, placebo controlled trial, the Paricalcitol and ENdothelial fuNction in chronic kidneY disease (PENNY). METHODS AND RESULTS Eighty-eight patients with stage 3-4 CKD were randomized (1:1) to receive 2 μg/day paricalcitol or matching placebo for 12 weeks. IR was measured by five IR indices: the homeostasis model assessment of insulin resistance (HOMA-IR), the quantitative insulin sensitivity check index (QUICKI), the McAuley index, the HOMA corrected for adiponectin (HOMA-AD) and the Leptin-adiponectin ratio (LAR). As compared to placebo, paricalcitol produced the expected small rise in serum calcium (+0.07 mmol/L, P = 0.01) and phosphate (+0.08 mmol/L, P = 0.034) and the expected parathyroid hormone suppression (-96 pg/ml, P < 0.001). However, the drug largely failed to affect the five indices of IR which remained unchanged both in the active and the placebo arm (paricalcitol vs placebo, P ranging from 0.25 to 0.62) and no effect modification of paricalcitol on IR by vitamin D or other parameters was registered. CONCLUSION Paricalcitol treatment for 12 weeks does not improve IR in patients with stage 3-4 CKD. Low vitamin D receptor activation is not a causal factor for IR in the CKD population.
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Affiliation(s)
- B Spoto
- CNR-IFC, Clinical Epidemiology and Physiopathology of Renal Diseases and Hypertension, Reggio Calabria, Italy
| | - P Pizzini
- CNR-IFC, Clinical Epidemiology and Physiopathology of Renal Diseases and Hypertension, Reggio Calabria, Italy
| | - S Cutrupi
- CNR-IFC, Clinical Epidemiology and Physiopathology of Renal Diseases and Hypertension, Reggio Calabria, Italy
| | - G Tripepi
- CNR-IFC, Clinical Epidemiology and Physiopathology of Renal Diseases and Hypertension, Reggio Calabria, Italy
| | - G Curatola
- CNR-IFC, Clinical Epidemiology and Physiopathology of Renal Diseases and Hypertension, Reggio Calabria, Italy
| | - F Mallamaci
- CNR-IFC, Clinical Epidemiology and Physiopathology of Renal Diseases and Hypertension, Reggio Calabria, Italy; Nephrology Dialysis and Renal Transplantation Unit, Reggio Calabria, Italy
| | - C Zoccali
- CNR-IFC, Clinical Epidemiology and Physiopathology of Renal Diseases and Hypertension, Reggio Calabria, Italy.
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Abstract
Chronic kidney disease (CKD) is associated with high risk for cardiovascular disease (CVD). This association is multifactorial, but CKD is often associated with dyslipidemia, which likely contributes. Patients with CKD have dyslipidemia even at early stages of renal dysfunction and dyslipidemia tends to progress with deterioration of kidney function. The dyslipidemia in CKD is largely due to increased triglyceride levels, decreased HDL-C and varying levels of LDL-C. Current management of CKD may also affect lipid levels. Robust clinical trials demonstrate that statins are safe and efficacious in both lipid lowering and prevention of CVD events in pre-end stage CKD and post-transplant. However, there is no evidence of improved CVD outcomes with statin use in dialysis patients. This review will focus on mechanisms underlying dyslipidemia in CKD and clinical trial evidence for lipid lowering therapy in patients with CKD.
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Affiliation(s)
- Matthew R Hager
- Department of Internal Medicine University of Kentucky, Lexington, KY, USA
| | - Archana D Narla
- Division of Endocrinology and Molecular Medicine, University of Kentucky, Lexington, KY, USA
| | - Lisa R Tannock
- Division of Endocrinology and Molecular Medicine, University of Kentucky, Lexington, KY, USA.
- Department of Veterans Affairs, Lexington, KY, USA.
- University of Kentucky, 900 S. Limestone, Room 553 CTW, Lexington, KY, 40536-0200, USA.
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Abstract
Vitamin D deficiency is a worldwide public health problem. Vitamin D deficiency plays key role in the pathophysiology of risk factors of metabolic syndrome which affect cardiovascular system, increase insulin resistance and obesity, stimulate rennin-angiotensin-aldosterone system that cause hypertension. The discovery of vitamin D receptor expressed ubiquitously in almost all body cells such as immune, vascular and myocardial cells, pancreatic beta cells, neurons and osteoblasts suggests an involvement of vitamin D mediated effects on metabolic syndrome. Moreover vitamin D deficiency as well as cardiovascular diseases and related risk factors frequently co-occur. This underlines the importance of understanding the role of vitamin D in the context of metabolic syndrome. The paper provides an insight into the physiology of vitamin D and relationship of vitamin D deficiency with risk factors of metabolic syndrome through observational and supplementation studies.
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Affiliation(s)
- Priyanka Prasad
- Department of Food and Nutrition, Punjab Agricultural University, Ludhiana 141004, Punjab, India.
| | - Anita Kochhar
- Department of Food and Nutrition, Punjab Agricultural University, Ludhiana 141004, Punjab, India.
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Bushinsky DA, Messa P. Efficacy of early treatment with calcimimetics in combination with reduced doses of vitamin d sterols in dialysis patients. NDT Plus 2015; 1:i18-i23. [PMID: 25983951 PMCID: PMC4421152 DOI: 10.1093/ndtplus/sfm040] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2007] [Accepted: 09/10/2007] [Indexed: 01/08/2023] Open
Abstract
Vitamin D is an important physiologic regulator of bone and mineral metabolism. In chronic kidney disease, reduced renal production of calcitriol contributes to secondary hyperparathyroidism (SHPT). Consequently, supplementation with vitamin D sterols is an important treatment for SHPT and its associated mineral and bone disorders. However, doses of vitamin D sterols required to suppress parathyroid hormone (PTH) secretion often promote hypercalcaemia and hyperphosphataemia. Therefore, there is a trade-off between reduced serum PTH and increased levels of serum calcium, phosphorus and calcium–phosphorus product. It has been suggested that treatment of SHPT with cinacalcet, a type II calcimimetic, with reduced doses of vitamin D sterols could enhance achievement of calcium and phosphorus treatment targets while maintaining goals for PTH. Recent clinical trials have evaluated this hypothesis and demonstrated that treatment with cinacalcet in combination with reduced doses of vitamin D sterols is an effective treatment for the management of SHPT.
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Sarathy H, Pramanik V, Kahn J, Abramowitz MK, Meier K, Kishore P, Melamed ML. The effects of short-term vitamin D supplementation on glucose metabolism in dialysis patients: a systematic review and meta-analysis. Int Urol Nephrol 2015; 47:537-49. [PMID: 25636811 DOI: 10.1007/s11255-015-0909-0] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2014] [Accepted: 01/02/2015] [Indexed: 12/26/2022]
Abstract
PURPOSE We tested whether short-term vitamin D supplementation improves insulin resistance in patients with kidney disease, a condition with little intrinsic vitamin D activity. METHODS PubMed, EMBASE and CENTRAL were searched for relevant observational studies and randomized clinical trials (RCTs). Random-effects models were employed for meta-analysis, and effect sizes were summarized as standardized mean difference (SMD) with 95% confidence intervals. Separate analyses were done for RCTs and non-randomized intervention studies (NRIS). RESULTS Seventeen studies (5 RCTs and 12 NRIS) were included. The meta-analysis population (n = 131) was mostly middle aged (40-50 years), male and non-diabetic, and on hemodialysis. The duration (4-12 weeks) and type of supplementation varied between studies. Among RCTs, compared to placebo, vitamin D supplementation was associated with significant decrease in fasting glucose [SMD -1.13, (-2.11 to -0.11)] and PTH levels [SMD -1.50, (-2.95 to -0.04)] but no difference in fasting insulin levels [SMD 1.32, (-0.15 to 2.79)]. Among NRIS, there was only a significant decrease in PTH levels [SMD -1.68, (-2.55 to -0.82)] between pre- and post-vitamin D treatment levels. CONCLUSIONS Short-term (4-12 weeks) supplementation with vitamin D is associated with lower fasting glucose levels in ESRD with no change in fasting insulin levels. However, the findings from this study are limited by the studies that were used in the meta-analysis, which were mostly small, used multiple different vitamin D compounds and dosing regimens, and had large heterogeneity, and funnel plots showed that there was a dearth of studies with null or negative finding. Therefore, larger RCTs need to be performed to answer this important clinical question.
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Affiliation(s)
- Harini Sarathy
- Department of Internal Medicine, Albert Einstein College of Medicine/Jacobi Medical Center, Bronx, NY, USA
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Petchey WG, Hickman IJ, Prins JB, Hawley CM, Johnson DW, Isbel NM. Vitamin D does not improve the metabolic health of patients with chronic kidney disease stage 3-4: A randomized controlled trial. Nephrology (Carlton) 2012; 18:26-35. [DOI: 10.1111/j.1440-1797.2012.01662.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/01/2012] [Indexed: 12/30/2022]
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Hung AM, Sundell MB, Plotnikova NE, Bian A, Shintani A, Ellis CD, Siew ED, Ikizler TA. A pilot study of active vitamin D administration and insulin resistance in African American patients undergoing chronic hemodialysis. J Ren Nutr 2012; 23:185-93. [PMID: 22959781 DOI: 10.1053/j.jrn.2012.06.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2012] [Revised: 06/20/2012] [Accepted: 06/25/2012] [Indexed: 12/19/2022] Open
Abstract
OBJECTIVE Insulin resistance (IR) is associated with increased cardiovascular risk in multiple patient populations, including those undergoing chronic hemodialysis (CHD). Active vitamin D deficiency has been proposed to play a role in the extent of IR observed in patients with CHD. We postulated that administration of paracalcitol, an active vitamin D medication, influences IR in patients with CHD. DESIGN AND METHODS This was a pilot randomized controlled trial. Ten prevalent CHD patients receiving a stable dose of paracalcitol were recruited. Paracalcitol was withheld for 8 weeks in all patients (phase I). Parathyroid hormone levels were managed with the calcium-sensing receptor agonist cinacalcet. At week 8, patients were randomized to continue cinacalcet or to restart paracalcitol for 8 weeks (phase II). The primary outcome was the change in IR measured by the glucose disposal rate (GDR) using hyperinsulinemic euglycemic clamp (HEGC) method. Secondary outcomes included changes in IR between groups in indirect indices of IR, biomarkers of inflammation, and adipokine levels. RESULTS The mean age was 49 years (range, 46-57 years) and 40% of patients were women. There was no detectable change in the GDR at the end of phase I (P = .7) when compared with baseline values. There was also no statistically significant difference in GDR between groups at the end of phase II (P = .9). No changes were observed in indirect indices of IR, adipokine levels, or biomarkers of inflammation in either phase. CONCLUSION The results of this pilot study suggest that withdrawal of paracalcitol over 8 to 16 weeks and replacement for 8 weeks after withdrawal does not influence IR measured by HEGC in patients receiving CHD.
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Affiliation(s)
- Adriana M Hung
- Clinical Science Research and Development, Veterans Administration Tennessee Valley Healthcare System, Nashville, Tennessee, USA
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Paricalcitol does not improve glucose metabolism in patients with stage 3-4 chronic kidney disease. Kidney Int 2012; 83:323-30. [PMID: 22913981 PMCID: PMC3509239 DOI: 10.1038/ki.2012.311] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Patients with chronic kidney disease are often insulin resistant and glucose intolerant--abnormalities that promote cardiovascular disease. Administration of 1,25-dihydroxyvitamin D (calcitriol) has improved glucose metabolism in patients with end-stage renal disease. We conducted a randomized, placebo-controlled clinical trial to test whether paricalcitol, a 1,25-dihydroxyvitamin D analog, changes glucose tolerance in earlier stages of chronic kidney disease. In a crossover design, 22 nondiabetic patients with estimated glomerular filtration rates of stage 3-4 chronic kidney disease and fasting plasma glucose of 100-125 mg/dl were given daily oral paricalcitol for 8 weeks and matching placebo for 8 weeks, separated by an 8-week washout period. The order of interventions was random and blinded to both participants and investigators. Paricalcitol significantly reduced serum concentrations of parathyroid hormone, 1,25-dihydroxyvitamin D, and 25-hydroxyvitamin D while significantly increasing serum concentrations of fibroblast growth factor-23 and 24,25-dihydroxyvitamin D. Paricalcitol, however, had no significant effect on glucose tolerance (the primary outcome measure), insulin sensitivity, beta-cell insulin response, plasma free fatty acid suppression, or urinary F2-isoprostane excretion. Thus, despite substantial effects on vitamin D metabolism, paricalcitol did not improve glucose metabolism in nondiabetic patients with stage 3-4 chronic kidney disease.
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Wang H, Xia N, Yang Y, Peng DQ. Influence of vitamin D supplementation on plasma lipid profiles: a meta-analysis of randomized controlled trials. Lipids Health Dis 2012; 11:42. [PMID: 22433171 PMCID: PMC3325888 DOI: 10.1186/1476-511x-11-42] [Citation(s) in RCA: 166] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2012] [Accepted: 03/20/2012] [Indexed: 12/17/2022] Open
Abstract
Observational studies have shown that low serum levels of vitamin D have been associated with an atherogenic lipid profile. However, the intervention studies gave divergent results. We conducted a meta-analysis of randomized controlled trials that evaluated the effects of vitamin D supplementation on blood lipids. A systematic literature search was conducted via MEDLINE, Cochrane library, and EMBASE for randomized controlled clinical trials assessing the effects of vitamin D supplementation on lipids. The mean change in total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C) and triglycerides (TG) from baseline was treated as a continuous variable. In all, 12 clinical trials consisting of 1346 participants were included in the analysis. The pooled estimate of effect for vitamin D supplementation on LDL-C was 3.23 mg/dl (95% confidence interval, 0.55 to 5.90 mg/dl). No statistically significant effects for vitamin D supplementation were observed for TC, HDL-C and TG (differences in means were 1.52 mg/dl (-1.42 to 4.46 mg/dl), -0.14 mg/dl (-0.99 to 0.71 mg/dl) and -1.92 mg/dl (-7.72 to 3.88 mg/dl) respectively). The lipid modulating effects of vitamin D supplementation should be further investigated though large-scale, randomized trials with adequate doses which can effectively elevated the active form of vitamin D in plasma and with proper population which has hyperlipemia as an inclusion criterion.
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Affiliation(s)
- Hao Wang
- Department of Cardiology, the Second Xiangya Hospital, Central South University, Changsha, Hunan, People's Republic of China
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12
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Vitamin D3 and the risk of CVD in overweight and obese women: a randomised controlled trial. Br J Nutr 2012; 108:1866-73. [PMID: 22317756 DOI: 10.1017/s0007114512000098] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Evidence indicates that vitamin D deficiency contributes to CVD. We investigated the effect of vitamin D3 supplementation on cardiovascular risk factors in women. Healthy premenopausal overweight and obese women (n 77; mean age 38 (sd 8·1) years) were randomly allocated to the vitamin D (25 μg/d as cholecalciferol) or the placebo group in a double-blind manner for 12 weeks. Blood pressure, serum lipoproteins, apolipoproteins and anthropometric parameters were recorded. Dietary intake was recorded using 24 h food recall and FFQ. Physical activity was assessed by the International Physical Activity Questionnaire. Mean total cholesterol concentrations increased in the vitamin D group (0·08 (sd 0·56) mmol/l) but declined in the placebo group (0·47 (sd 0·58) mmol/l), and a significant effect was observed (P ≤ 0·001). In the vitamin D group, mean HDL-cholesterol concentration increased, whereas it decreased in the placebo group (0·07 (sd 0·2) v. - 0·03 (sd 0·2) mmol/l; P = 0·037). Mean apoA-I concentration increased in the vitamin D group, although it decreased in the placebo group (0·04 (sd 0·39) v. - 0·25 (sd 0·2) g/l; P ≤ 0·001). Mean LDL-cholesterol:apoB-100 ratio augmented in the vitamin D group, while this ratio declined in the placebo group (0·11 (sd 0·6) v. - 0·19 (sd 0·3); P = 0·014). Body fat mass was significantly decreased in the vitamin D group more than the placebo group ( - 2·7 (sd 2) v. - 0·4 (sd 2) kg; P ≤ 0·001). The findings showed that supplementation with vitamin D3 can significantly improve HDL-cholesterol, apoA-I concentrations and LDL-cholesterol:apoB-100 ratio, which remained significant in the multivariate model including anthropometric, dietary and physical activity measures.
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Abstract
PURPOSE OF REVIEW Insulin resistance is a known complication of end-stage renal disease that also appears to be present in earlier stages of chronic kidney disease (CKD). It is a risk factor for cardiovascular disease and an important potential therapeutic target in this population. Measurement of insulin resistance is reviewed in the context of known pathophysiologic abnormalities in CKD. RECENT FINDINGS Insulin resistance in CKD is due to a high prevalence of known risk factors (e.g. obesity) and to unique metabolic abnormalities. The site of insulin resistance in CKD is localized to skeletal muscle. Estimates based on fasting insulin concentration may not adequately capture insulin resistance in CKD because they largely reflect hepatic defects and because CKD impairs insulin catabolism. A variety of dynamic tests are available to directly measure insulin-mediated glucose uptake. SUMMARY Insulin resistance may be an important therapeutic target in CKD. Complementary methods are available to assess insulin resistance, and each method has unique advantages, disadvantages, and levels of complexity. These characteristics, and the likelihood that CKD alters the performance of some insulin resistance measurements, must be considered when designing and interpreting clinical studies.
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Petchey WG, Johnson DW, Isbel NM. Shining D' light on chronic kidney disease: mechanisms that may underpin the cardiovascular benefit of vitamin D. Nephrology (Carlton) 2011; 16:351-67. [PMID: 21323790 DOI: 10.1111/j.1440-1797.2011.01450.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Hypovitaminosis D is a significant health-care burden worldwide, particularly in susceptible populations such as those with chronic kidney disease (CKD). Recent epidemiological studies have identified that both higher serum vitamin D concentrations and use of vitamin D supplements may confer a survival benefit both in terms of all-cause and cardiovascular mortality. There is potential to investigate this inexpensive therapy for the CKD population, which suffers excessive cardiovascular events, although the mechanisms explaining this link have yet to be fully elucidated. This review discusses potential mechanisms identified in the basic science literature that may provide important insights into how vitamin D may orchestrate a change in cardiovascular risk profile through such diverse mechanisms as inflammation, atherogenesis, glucose homeostasis, vascular calcification, renin-angiotensin regulation and alterations in cardiac physiology. Where available, the clinical translation of these concepts to intervention trials in the CKD population will be reviewed.
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Affiliation(s)
- William G Petchey
- Centre for Clinical Research Excellence-Cardiovascular Disease and Metabolic Disorders, University of Queensland, Brisbane, Queensland, Australia.
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Palmer SC, McGregor DO, Craig JC, Elder G, Macaskill P, Strippoli GF. Vitamin D compounds for people with chronic kidney disease requiring dialysis. Cochrane Database Syst Rev 2009:CD005633. [PMID: 19821349 DOI: 10.1002/14651858.cd005633.pub2] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
BACKGROUND Clinical guidelines recommend vitamin D compounds to suppress serum parathyroid hormone (PTH) in chronic kidney disease (CKD), however treatment may be associated with increased serum phosphorus and calcium, which are associated with increased mortality in observational studies. Observational data also indicate vitamin D therapy may be independently associated with reduced mortality in CKD. OBJECTIVES We assessed the effects of vitamin D compounds on clinical, biochemical, and bone outcomes in people with CKD and receiving dialysis. SEARCH STRATEGY We searched The Cochrane Renal Group's specialised register, Cochrane's Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, and reference lists of retrieved articles. SELECTION CRITERIA Randomised controlled trials (RCTs) in subjects with CKD and requiring dialysis that assessed treatment with vitamin D compounds. DATA COLLECTION AND ANALYSIS Data was extracted by two authors. Results are summarised as risk ratios (RR) for dichotomous outcomes or mean differences (MD) for continuous outcomes, with 95% confidence intervals (CI). MAIN RESULTS Sixty studies (2773 patients) were included. No formulation, route, or schedule of administration was associated with altered risks of death, bone pain, or parathyroidectomy. Marked heterogeneity in reporting of outcomes resulted in few data available for formal meta-analysis. Compared with placebo, vitamin D compounds lowered serum PTH at the expense of increasing serum phosphorus. Trends toward increased hypercalcaemia and serum calcium did not reach statistical significance but may be clinically relevant. Newer vitamin D compounds (paricalcitol, maxacalcitol, doxercalciferol) lowered PTH compared with placebo, with increased risks of hypercalcaemia, although inadequate data were available for serum phosphorus. Intravenous vitamin D may lower PTH compared with oral treatment, and be associated with lower serum phosphorus and calcium levels, although limitations in the available studies precludes a conclusive statement of treatment efficacy. Few studies were available for intermittent versus daily and intraperitoneal versus oral administration or directly comparative studies of newer versus established vitamin D compounds. AUTHORS' CONCLUSIONS We confirm that vitamin D compounds suppress PTH in people with CKD and requiring dialysis although treatment is associated with clinical elevations in serum phosphorus and calcium. All studies were inadequately powered to assess the effect of vitamin D on clinical outcomes and until such studies are conducted the relative importance of changes in serum PTH, phosphorus and calcium resulting from vitamin D therapy remain unknown. Observational data showing vitamin D compounds may be associated with improved survival in CKD need to be confirmed or refuted in specifically designed RCTs.
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Affiliation(s)
- Suetonia C Palmer
- Renal Division, Brigham and Women's Hospital, Harvard Medical School, Harvard Institute of Medicine, Room 550, 4 Blackfan Street, Boston, MA, USA, 02115
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Zanos S, Mitsopoulos E, Sakellariou G. Parathyroid Hormone Levels, Calcium-Channel Blockers, and the Dyslipidemia of Nondiabetic Hemodialysis Patients. Ren Fail 2009. [DOI: 10.1081/jdi-48229] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
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Abstract
PURPOSE OF REVIEW Vitamin D deficiency has been linked with impaired glucose metabolism, an established risk factor for cardiovascular disease. Effects of vitamin D may be particularly important in chronic kidney disease, because vitamin D metabolism is substantially impaired in this setting. The present review examines the potential role of vitamin D in improving glucose metabolism and clinical health outcomes in chronic kidney disease. RECENT FINDINGS Impaired glucose metabolism is common in chronic kidney disease. Short-term studies on maintenance hemodialysis patients have shown that vitamin D treatment improves insulin secretion and sensitivity. Intervention studies on people without end-stage renal disease have yielded mixed results. Mounting evidence from observational studies links vitamin D treatment with decreased mortality. SUMMARY Vitamin D therapy holds promise for improving health outcomes in chronic kidney disease. Improved glucose metabolism is one potential mechanism through which vitamin D may exert beneficial effects. However, further data from clinical trials are needed to test whether vitamin D has clinically relevant long-term effects on glucose metabolism and overall clinical outcomes.
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Botella-Carretero JI, Alvarez-Blasco F, Villafruela JJ, Balsa JA, Vázquez C, Escobar-Morreale HF. Vitamin D deficiency is associated with the metabolic syndrome in morbid obesity. Clin Nutr 2007; 26:573-80. [PMID: 17624643 DOI: 10.1016/j.clnu.2007.05.009] [Citation(s) in RCA: 176] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2006] [Revised: 03/30/2007] [Accepted: 05/24/2007] [Indexed: 12/18/2022]
Abstract
BACKGROUND & AIMS Vitamin D deficiency has been recently associated with the metabolic syndrome. However, it is not known whether this possible association of vitamin D deficiency with the metabolic syndrome is still present at very high degrees of obesity, as in morbidly obese patients. METHODS Transversal, observational study that included 73 consecutive morbidly obese patients (body mass index 40 kg/m(2)). In every patient, anthropometric variables were recorded, fasting blood was assayed for 25-hydroxyvitamin D concentrations, lipid profiles, glucose and insulin levels, and insulin resistance was estimated by homeostasis model assessment. RESULTS Vitamin D deficiency was present in 37 of the 73 patients (50.7%). As defined by revised Adult Treatment Panel III criteria, 46 of the 73 obese patients (63%) had the metabolic syndrome. Vitamin D deficiency was more prevalent in morbidly obese patients presenting with the metabolic syndrome, compared with those who did not achieve the criteria for this syndrome (60.9% vs. 33.3% respectively, P = 0.023). When serum concentrations of 25-hydroxyvitamin D were categorized in tertiles, there was an association of the prevalence of the metabolic syndrome with the former (P = 0.038). Serum high-density lipoprotein cholesterol concentrations were lower (37.0+/-7.8 mg/dl vs. 44.9+/-8.7 mg/dl, P = 0.003), and triglycerides levels were higher (163.3+/-81.5 mg/dl vs. 95.1+/-24.2 mg/dl, P = 0.001) in the vitamin D-deficient group. CONCLUSION Vitamin D deficiency is associated with the metabolic syndrome in morbidly obese patients.
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Need AG, O'Loughlin PD, Horowitz M, Nordin BEC. Relationship between fasting serum glucose, age, body mass index and serum 25 hydroxyvitamin D in postmenopausal women. Clin Endocrinol (Oxf) 2005; 62:738-41. [PMID: 15943837 DOI: 10.1111/j.1365-2265.2005.02288.x] [Citation(s) in RCA: 110] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
OBJECTIVE Because it has been reported that vitamin D, given to mother or infant, can prevent type I diabetes in children, that diabetes is more common in adults with low serum vitamin D and that insulin secretion and action are related to vitamin D levels in healthy young adults we examined the relationship between serum vitamin D metabolites and fasting serum glucose in patients attending our outpatient clinics. DESIGN Retrospective examination of convenience sample of postmenopausal women attending our osteoporosis clinics. PATIENTS A total of 753 postmenopausal women attending a university hospital outpatient clinic and not on any treatment known to affect glucose metabolism. MEASUREMENTS Body weight and height, serum 25-hydroxyvitamin D [25(OH)D], serum 1,25-dihydroxyvitamin D [1,25(OH)2D], serum PTH and fasting serum glucose. RESULTS On simple correlation fasting serum glucose was a positive function of age (P < 0.05), weight (P < 0.001) and body mass index (BMI) (P < 0.001) and a negative function of serum 25(OH)D (P < 0.001), but it was not significantly related to either serum 1,25(OH)2D, PTH or creatinine. When fasting serum glucose was regressed simultaneously on age, BMI and 25(OH)D, glucose was still an inverse function of 25(OH)D (P = 0.006). CONCLUSIONS Fasting serum glucose increased as 25(OH)D levels fell throughout the range of serum 25(OH)D measured but the greatest increase was observed in those with 25(OH)D below 40 nmol/l.
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Affiliation(s)
- Allan G Need
- Division of Clinical Biochemistry, Institute of Medical and Veterinary Science, University of Adelaide, Adelaide, SA, Australia.
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Kronenberg F, Lingenhel A, Lhotta K, Rantner B, Kronenberg MF, König P, Thiery J, Koch M, von Eckardstein A, Dieplinger H. Lipoprotein(a)- and low-density lipoprotein-derived cholesterol in nephrotic syndrome: Impact on lipid-lowering therapy? Kidney Int 2005; 66:348-54. [PMID: 15200443 DOI: 10.1111/j.1523-1755.2004.00737.x] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
BACKGROUND Patients with nephrotic syndrome have the highest lipoprotein(a) [Lp(a)] concentrations known. Lp(a) is an low-density lipoprotein (LDL)-like particle consisting of 45% cholesterol. The usual methods to determine LDL cholesterol do not distinguish between cholesterol derived from LDL and Lp(a) and are thus the net result of cholesterol levels from both lipoproteins. High Lp(a) concentrations therefore significantly contribute to the measured or calculated LDL cholesterol levels. Since statins have no influence on Lp(a) levels, it can be expected that the LDL cholesterol-lowering effect of statins may be diminished in patients who have a pronounced elevation of Lp(a) levels accompanied by only moderate elevations of LDL cholesterol. METHODS We investigated 207 patients with nondiabetic nephrotic syndrome in whom Lp(a) concentrations were strikingly elevated when compared to 274 controls (60.4 +/- 85.4 mg/dL vs. 20.0 +/- 32.8 mg/dL, P < 0.0001). RESULTS According to National Kidney Foundation Dialysis Outcomes Quality Initiative (K/DOQI) Clinical Practice Guidelines for Managing Dyslipidemias, almost 95% of these patients are candidates for a therapeutic intervention to lower LDL cholesterol. LDL cholesterol levels corrected for Lp(a)-derived cholesterol, however, were 27 mg/dL lower than uncorrected concentrations (compared to only 9 mg/dL in controls). If Lp(a)-corrected levels instead of total LDL cholesterol levels were used, 25.7% of patients with low-molecular-weight (LMW) apolipoprotein(a) [apo(a)] isoforms were classified no longer to be in need of LDL cholesterol-lowering therapeutic intervention compared to only 2.3% of patients with high-molecular-weight (HMW) apo(a) phenotypes (P < 0.00001). This ("pseudo") pharmacogenetic effect results in incorrect determination of LDL cholesterol. CONCLUSION Our observation has an impact on the indication for, and assessment of efficacy of intervention. This potential artifact should be investigated in ongoing large trials in renal patients as well as in nonrenal African American subjects who have on average markedly higher Lp(a) levels. In nonrenal Caucasian subjects with much lower Lp(a) concentrations, this issue will be less relevant.
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Affiliation(s)
- Florian Kronenberg
- Department of Medical Biology and Human Genetics, Medical University of Innsbruck, Innsbruck, Austria.
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Current awareness: Pharmacoepidemiology and drug safety. Pharmacoepidemiol Drug Saf 2003; 12:617-32. [PMID: 14558186 DOI: 10.1002/pds.793] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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