The effect of vitamin D supplementation on the glycemic control of pre-diabetic Qatari patients in a randomized control trial

Abstract Background: Vitamin D deficiency is associated with indicators of pre-diabetes including, insulin resistance, β-cell dysfunction and elevated plasma glucose with controversial findings from current trials. This study aims to investigate the long-term effect of vitamin D on glucose metabolism and insulin sensitivity in pre-diabetic and highly vitamin-deficient subjects. Methods: 132 participants were randomized to 30,000 IU vitamin D weekly for 6 months. Participants underwent oral glucose tolerance test (OGTT) at 3-month intervals to determine the change in plasma glucose concentration at 2h after 75g OGTT (2hPCG). Secondary measurements included glycated hemoglobin, fasting plasma glucose and insulin, post-prandial insulin, indices of insulin sensitivity (HOMA-IR, Matsuda Index), β-cell function (HOMA-β, glucose and insulin area under the curve (AUC), disposition and insulinogenic indices), and lipid profile. Results: A total of 57 (vitamin D) and 75 (placebo) subjects completed the study. Mean baseline serum 25(OH) D levels were 17.0 ng/ml and 14.9 ng/ml for placebo and vitamin D group, respectively. No significant differences were observed for 2hPC glucose or insulin sensitivity indices between groups. HOMA-β significantly decreased in the vitamin D group, while area under curve for glucose and insulin showed a significant reduction in β-cell function in both groups. Additionally, HOMA-β was found to be significantly different between control and treatment group and significance persisted after adjusting for confounding factors. Conclusion: Vitamin D supplementation in a pre-diabetic and severely vitamin-deficient population had no effect on glucose tolerance or insulin sensitivity. The observed reduction in β-cell function in both placebo and vitamin D groups could be attributed to factors other than supplementation. Trial registration: The trial was registered at www.clinicaltrials.gov with number: NCT02098980.

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The effect of vitamin D supplementation on the glycemic control of pre-diabetic Qatari patients in a randomized control trial.

10.21203/rs.2.11375/v3 ◽

2019 ◽

Author(s):

Mohammed Al Thani ◽

Eman Sadoun ◽

Angeliki Sofroniou ◽

Amin Jayyousi ◽

Khaled Ahmed Mohamed Baagar ◽

...

Keyword(s):

Vitamin D ◽

Insulin Sensitivity ◽

Glucose Tolerance ◽

Plasma Glucose ◽

Cell Function ◽

Vitamin D Supplementation ◽

Oral Glucose ◽

Β Cell ◽

Baseline Serum ◽

Β Cell Function

Abstract Background: Vitamin D deficiency is associated with indicators of pre-diabetes including, insulin resistance, β-cell dysfunction and elevated plasma glucose with controversial findings from current trials. This study aims to investigate the long-term effect of vitamin D on glucose metabolism and insulin sensitivity in pre-diabetic and highly vitamin-deficient subjects. Methods: 132 participants were randomized to 30,000 IU vitamin D weekly for 6 months. Participants underwent oral glucose tolerance test (OGTT) at 3-month intervals to determine the change in plasma glucose concentration at 2h after 75g OGTT (2hPCG). Secondary measurements included glycated hemoglobin, fasting plasma glucose and insulin, post-prandial insulin, indices of insulin sensitivity (HOMA-IR, Matsuda Index), β-cell function (HOMA-β, glucose and insulin area under the curve (AUC), disposition and insulinogenic indices), and lipid profile. Results: A total of 57 (vitamin D) and 75 (placebo) subjects completed the study. Mean baseline serum 25(OH) D levels were 17.0 ng/ml and 14.9 ng/ml for placebo and vitamin D group, respectively. No significant differences were observed for 2hPC glucose or insulin sensitivity indices between groups. HOMA-β significantly decreased in the vitamin D group, while area under curve for glucose and insulin showed a significant reduction in β-cell function in both groups. Additionally, HOMA-β was found to be significantly different between control and treatment group and significance persisted after adjusting for confounding factors. Conclusion: Vitamin D supplementation in a pre-diabetic and severely vitamin-deficient population had no effect on glucose tolerance or insulin sensitivity. The observed reduction in β-cell function in both placebo and vitamin D groups could be attributed to factors other than supplementation. Trial registration: NCT02098980, 28/03/2014 (www.clinicaltrials.gov).

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The effect of vitamin D supplementation on the glycemic control of pre-diabetic Qatari patients in a randomized control trial.

10.21203/rs.2.11375/v2 ◽

2019 ◽

Author(s):

Mohammed Al Thani ◽

Eman Sadoun ◽

Angeliki Sofroniou ◽

Amin Jayyousi ◽

Khaled Ahmed Mohamed Baagar ◽

...

Keyword(s):

Vitamin D ◽

Insulin Sensitivity ◽

Glucose Tolerance ◽

Plasma Glucose ◽

Cell Function ◽

Vitamin D Supplementation ◽

Oral Glucose ◽

Β Cell ◽

Baseline Serum ◽

Β Cell Function

Abstract Background: Vitamin D deficiency is associated with indicators of pre-diabetes including, insulin resistance, β-cell dysfunction and elevated plasma glucose with controversial findings from current trials. This study aims to investigate the long-term effect of vitamin D on glucose metabolism and insulin sensitivity in pre-diabetic and highly vitamin-deficient subjects. Methods: 132 participants were randomized to 30,000 IU vitamin D weekly for 6 months. Participants underwent oral glucose tolerance test (OGTT) at 3-month intervals to determine the change in plasma glucose concentration at 2h after 75g OGTT (2hPCG). Secondary measurements included glycated hemoglobin, fasting plasma glucose and insulin, post-prandial insulin, indices of insulin sensitivity (HOMA-IR, Matsuda Index), β-cell function (HOMA-β, glucose and insulin area under the curve (AUC), disposition and insulinogenic indices), and lipid profile. Results: A total of 57 (vitamin D) and 75 (placebo) subjects completed the study. Mean baseline serum 25(OH) D levels were 17.0 ng/ml and 14.9 ng/ml for placebo and vitamin D group, respectively. No significant differences were observed for 2hPC glucose or insulin sensitivity indices between groups. HOMA-β significantly decreased in the vitamin D group, while area under curve for glucose and insulin showed a significant reduction in β-cell function in both groups. Additionally, HOMA-β was found to be significantly different between control and treatment group and significance persisted after adjusting for confounding factors. Conclusion: Vitamin D supplementation in a pre-diabetic and severely vitamin-deficient population had no effect on glucose tolerance or insulin sensitivity. The observed reduction in β-cell function in both placebo and vitamin D groups could be attributed to factors other than supplementation. Trial registration: The trial was registered at www.clinicaltrials.gov with number: NCT02098980.

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No Effect of High-Dose Vitamin D Treatment on β-Cell Function, Insulin Sensitivity, or Glucose Homeostasis in Subjects With Abnormal Glucose Tolerance: A Randomized Clinical Trial

Diabetes Care ◽

10.2337/dc15-1057 ◽

2016 ◽

Vol 39 (3) ◽

pp. 345-352 ◽

Cited By ~ 33

Author(s):

Henrik Wagner ◽

Michael Alvarsson ◽

Buster Mannheimer ◽

Marie Degerblad ◽

Claes-Göran Östenson

Keyword(s):

Clinical Trial ◽

Vitamin D ◽

Insulin Sensitivity ◽

Glucose Tolerance ◽

Cell Function ◽

High Dose ◽

Abnormal Glucose Tolerance ◽

Β Cell ◽

Β Cell Function ◽

High Dose Vitamin

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Effects of Combined Calcium and Vitamin D Supplementation on Insulin Secretion, Insulin Sensitivity and β-Cell Function in Multi-Ethnic Vitamin D-Deficient Adults at Risk for Type 2 Diabetes: A Pilot Randomized, Placebo-Controlled Trial

PLoS ONE ◽

10.1371/journal.pone.0109607 ◽

2014 ◽

Vol 9 (10) ◽

pp. e109607 ◽

Cited By ~ 64

Author(s):

Claudia Gagnon ◽

Robin M. Daly ◽

André Carpentier ◽

Zhong X. Lu ◽

Catherine Shore-Lorenti ◽

...

Keyword(s):

Type 2 Diabetes ◽

Vitamin D ◽

Insulin Secretion ◽

Insulin Sensitivity ◽

Cell Function ◽

Controlled Trial ◽

Vitamin D Supplementation ◽

Β Cell ◽

Β Cell Function

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Vitamin D and Parathyroid Hormone Status in Pregnancy: Effect on Insulin Sensitivity, β-cell Function, and Gestational Diabetes Mellitus

The Journal of Clinical Endocrinology & Metabolism ◽

10.1210/jc.2014-2341 ◽

2014 ◽

Vol 99 (12) ◽

pp. 4506-4513 ◽

Cited By ~ 27

Author(s):

Caroline K. Kramer ◽

Balakumar Swaminathan ◽

Anthony J. Hanley ◽

Philip W. Connelly ◽

Mathew Sermer ◽

...

Keyword(s):

Vitamin D ◽

Insulin Sensitivity ◽

Glucose Tolerance ◽

Vitamin D Deficiency ◽

Cell Function ◽

Β Cell ◽

Matsuda Index ◽

Β Cell Function ◽

Glucose Tolerance Status ◽

In Pregnancy

Context: Previous studies have yielded conflicting findings on the relationship between vitamin D deficiency/insufficiency and gestational diabetes mellitus (GDM). We hypothesized that PTH may be an underlying factor relevant to this potential association. Objective: This study sought to evaluate the effect of vitamin D and PTH status on insulin sensitivity, β-cell function, and glycemia in pregnancy. Setting and Design: Five-hundred-twenty-four women underwent a glucose challenge test (GCT) and oral glucose tolerance test (OGTT) in late second/early third trimester. The GCT/OGTT identified 142 women with GDM, 94 with gestational impaired glucose tolerance, 163 with an abnormal GCT and normal OGTT, and 125 with normal GCT and OGTT. Main Outcomes: Glycemia was assessed by glucose tolerance status and area under the glucose curve (AUCgluc) on the OGTT. Insulin sensitivity and β-cell function were assessed by Matsuda index and Insulin Secretion-Sensitivity Index-2 (ISSI-2), respectively. Results: There were 166 women (31.7%) with vitamin D deficiency (25-OH-D < 50 nmol/L), 178 (34%) with insufficiency (25-OH-D ≥ 50 nmol/L and < 75 nmol/L), and 180 (34.3%) with sufficiency (25-OH-D ≥ 75 nmol/L). Vitamin D status was not associated with Matsuda index, ISSI-2, AUCgluc, or glucose tolerance status. In contrast, ISSI-2 decreased and AUCgluc increased across ascending tertiles of PTH (P = .06 and P = .002, respectively). Indeed, the prevalence of GDM progressively increased from the first (22.6%) to second (25.8%) to third (33.5%) tertile of PTH (P < .001). On logistic regression analyses, the third tertile of PTH was independently associated with GDM (adjusted OR = 1.82; 95% CI, 1.09–3.02; P = .022), whereas vitamin D deficiency and insufficiency were not significant predictors of GDM. Conclusions: Increased PTH, rather than vitamin D deficiency/insufficiency, is independently associated with dysglycemia in pregnancy.

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Effects of vitamin D supplementation on insulin sensitivity and secretion in prediabetes

The Journal of Clinical Endocrinology & Metabolism ◽

10.1210/clinem/dgab649 ◽

2021 ◽

Author(s):

Neda Rasouli ◽

Irwin G Brodsky ◽

Ranee Chatterjee ◽

Sun H Kim ◽

Richard E Pratley ◽

...

Keyword(s):

Vitamin D ◽

Insulin Sensitivity ◽

Vitamin D3 ◽

Cell Function ◽

Vitamin D Supplementation ◽

Vitamin D Status ◽

Β Cell ◽

C Peptide ◽

Β Cell Function

Abstract Context Vitamin D regulates glucose homeostasis pathways, but effects of vitamin D supplementation on insulin sensitivity and β-cell function remain unclear. Objective To investigate the effects of vitamin D3 supplementation on insulin sensitivity and β-cell function. Methods This is a pre-specified secondary analysis of the Vitamin D and type 2 diabetes (D2d) study. Overweight/obese adults at high risk for type 2 diabetes were randomly treated with vitamin D3 4000 IU or matching placebo daily for 24 months. Main Outcome Disposition index (DI), as an estimate of β-cell function, was calculated as the product of HOMA2%Scpep and C-peptide response during the first 30 minutes of a 75-gram oral glucose tolerance test (OGTT). Results Mean age was 60.5±9.8 years and BMI was 31.9±4.4 kg/m 2. Mean serum 25(OH)D level increased from 27.9±10.3 ng/mL at baseline to 54.9 ng/mL at two years in the vitamin D group and was unchanged (28.5±10.0 ng/mL) in the placebo group. The baseline DI predicted incident diabetes independent of the intervention. In the entire cohort, there were no significant differences in changes in DI, HOMA2%Scpep, or C-peptide response between the two groups. Among participants with baseline 25(OH)D level <12 ng/mL, the mean percent differences for DI between the vitamin D and placebo groups was 8.5% (95%CI 0.2-16.8). Conclusions Supplementation with vitamin D3 for 24 months did not improve an OGTT-derived index of β-cell function in people with prediabetes not selected based on baseline vitamin D status; however, there was benefit among those with very low baseline vitamin D status.

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Effects of 6-month vitamin D supplementation on insulin sensitivity and secretion: a randomised, placebo-controlled trial

Acta Endocrinologica ◽

10.1530/eje-19-0156 ◽

2019 ◽

Vol 181 (3) ◽

pp. 287-299 ◽

Cited By ~ 14

Author(s):

Patricia Lemieux ◽

S John Weisnagel ◽

Annabelle Z Caron ◽

Anne-Sophie Julien ◽

Anne-Sophie Morisset ◽

...

Keyword(s):

Vitamin D ◽

Insulin Sensitivity ◽

Cell Function ◽

Controlled Trial ◽

Vitamin D Supplementation ◽

Insulinogenic Index ◽

Newly Diagnosed ◽

Β Cell ◽

Β Cell Function

Objective To determine whether vitamin D3 supplementation improves insulin sensitivity, using the hyperinsulinemic-euglycemic clamp. Design This single-centre, double-blind, placebo-controlled trial randomised 96 participants at high risk of diabetes or with newly diagnosed type 2 diabetes to vitamin D3 5000 IU daily or placebo for 6 months. Methods We assessed at baseline and 6 months: (1) primary aim: peripheral insulin sensitivity (M-value using a 2-h hyperinsulinemic-euglycemic clamp); (2) secondary aims: other insulin sensitivity (HOMA2%S, Matsuda) and insulin secretion (insulinogenic index, C-peptide area under the curve, HOMA2-B) indices using a 2-h oral glucose tolerance test (OGTT); β-cell function (disposition index: M-value × insulinogenic index); fasting and 2-h glucose post OGTT; HbA1c; anthropometry. Results Baseline characteristics were similar between groups (% or mean ± s.d.): women 38.5%; age 58.7 ± 9.4 years; BMI 32.2 ± 4.1 kg/m2; prediabetes 35.8%; diabetes 20.0%; 25-hydroxyvitamin D (25(OH)D) 51.1 ± 14.2 nmol/L. At 6 months, mean 25(OH)D reached 127.6 ± 26.3 nmol/L and 51.8 ± 16.5 nmol/L in the treatment and placebo groups, respectively (P < 0.001). A beneficial effect of vitamin D3 compared with placebo was observed on M-value (mean change (95% CI): 0.92 (0.24–1.59) vs −0.03 (−0.73 to 0.67); P = 0.009) and disposition index (mean change (95% CI): 267.0 (−343.4 to 877.4) vs −55.5 (−696.3 to 585.3); P = 0.039) after 6 months. No effect was seen on other outcomes. Conclusions In individuals at high risk of diabetes or with newly diagnosed type 2 diabetes, vitamin D supplementation for 6 months significantly increased peripheral insulin sensitivity and β-cell function, suggesting that it may slow metabolic deterioration in this population.

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