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

BMC Nutrition ◽

10.1186/s40795-019-0311-x ◽

2019 ◽

Vol 5 (1) ◽

Cited By ~ 1

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 ◽

Β Cell ◽

Baseline Serum ◽

Link Type ◽

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 One hundred thirty-two 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 2 h after 75 g 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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Impaired β-cell function and decreased insulin sensitivity in subjects with normal oral glucose tolerance but isolated high glycosylated hemoglobin

Endocrine Journal ◽

10.1507/endocrj.ej17-0325 ◽

2018 ◽

Vol 65 (1) ◽

pp. 13-22 ◽

Cited By ~ 1

Author(s):

Qi Fu ◽

Min Sun ◽

Zhixiao Wang ◽

Wei He ◽

Yu Duan ◽

...

Keyword(s):

Insulin Sensitivity ◽

Glucose Tolerance ◽

Cell Function ◽

Glycosylated Hemoglobin ◽

Oral Glucose ◽

Oral Glucose Tolerance ◽

Β Cell ◽

Β Cell Function

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Estimation of β-cell function from the data of the oral glucose tolerance test

AJP Endocrinology and Metabolism ◽

10.1152/ajpendo.00341.2006 ◽

2007 ◽

Vol 292 (6) ◽

pp. E1575-E1580 ◽

Cited By ~ 9

Author(s):

Shinji Sakaue ◽

Shinji Ishimaru ◽

Daisuke Ikeda ◽

Yoshinori Ohtsuka ◽

Toshiro Honda ◽

...

Keyword(s):

Insulin Sensitivity ◽

Glucose Tolerance ◽

Glucose Tolerance Test ◽

Cell Function ◽

Tolerance Test ◽

Oral Glucose ◽

Sensitivity Index ◽

Β Cell ◽

Β Cell Function ◽

The Relationship

Although a hyperbolic relationship between insulin secretion and insulin sensitivity has been shown, the relationship has been often questioned. We examined the relationship using oral glucose tolerance test (OGTT)-derived indexes. A total of 374 Japanese subjects who had never been given a diagnosis of diabetes underwent a 75-g OGTT. In subjects with normal glucose tolerance (NGT), the ln [insulinogenic index (IGI)] was described by a linear function of ln ( x) ( x, insulin sensitivity index) in regression analysis when the reciprocal of the insulin resistance index in homeostasis model assessment, Matsuda's index, and oral glucose insulin sensitivity index were used as x. Because the 95% confidence interval of the slope of the regression line did not necessarily include −1, the relationships between IGI and x were not always hyperbolic, but power functions IGI × xα = a constant. We thought that IGI × xα was an appropriate β-cell function estimate adjusted by insulin sensitivity and referred to it as β-cell function index (BI). When Matsuda's index was employed as x, the BI values were decreased in subjects without NGT. Log BI had a better correlation with fasting plasma glucose (PG; FPG) and 2-h PG in non-NGT subjects than in NGT subjects. In subjects with any glucose tolerance, log BI was linearly correlated with 1-h PG and glucose spike (the difference between maximum PG and FPG). In conclusion, the relationship between insulin secretion and insulin sensitivity was not always hyperbolic. The BI is a useful tool in the estimation of β-cell function with a mathematical basis.

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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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Glucose metabolic disorder in Klinefelter syndrome: a retrospective analysis in a single Chinese hospital and literature review

BMC Endocrine Disorders ◽

10.1186/s12902-021-00893-5 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Shixuan Liu ◽

Tao Yuan ◽

Shuoning Song ◽

Shi Chen ◽

Linjie Wang ◽

...

Keyword(s):

Insulin Secretion ◽

Insulin Sensitivity ◽

Literature Review ◽

Glucose Tolerance ◽

Cell Function ◽

Klinefelter Syndrome ◽

Oral Glucose ◽

Model Assessment ◽

Β Cell ◽

Β Cell Function

Abstract Background We aimed to investigate the clinical characteristics and islet β-cell function in patients with Klinefelter syndrome (KS) and hyperglycemia. Methods This is a retrospective study. In total, 22 patients diagnosed with KS were identified from the electronic medical record system, including 9 patients with hyperglycemia (total patients with hyperglycemia, THG-KS group) and 5 hyperglycemic KS patients with oral glucose tolerance test (OGTT) results (HG-KS group). An additional 5 subjects with hyperglycemia and 5 normal glucose tolerance (NGT) subjects matched based on body mass index were included as the HG group and NGT group, respectively. Data from clinical and laboratory examinations were collected. We further performed a literature review of KS and hyperglycemia. Results We found that KS patients developed abnormal glucose metabolism earlier in life than those without KS, and the median age was 17 years, ranging from 10 years to 19 years. Six of 17 (35.3%) patients were diagnosed with diabetes mellitus and 3 of 17 (17.6%) patients were diagnosed with prediabetes. Among 10 patients with both fasting blood glucose and insulin results recorded, there were 8 out of 17 (47.1%) KS patients had insulin resistance. The prevalence of hypertension and dyslipidemia was higher in patients with hyperglycemia and KS than in patients with NGT KS. Compared with the HG group, insulin sensitivity levels were lower in HG-KS group, whereas homeostasis model assessment of β-cell function levels (p = 0.047) were significantly, indicating higher insulin secretion levels in the HG-KS group. Conclusions KS patients develop hyperglycemia earlier in life than those without KS and show lower insulin sensitivity and higher insulin secretion. These patients also have a higher prevalence of other metabolic diseases and may have different frequencies of developing KS-related symptoms.

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Early Detection of Insulin Sensitivity and β-Cell Function with Simple Tests Indicates Future Derangements in Late Pregnancy

The Journal of Clinical Endocrinology & Metabolism ◽

10.1210/jc.2007-1363 ◽

2008 ◽

Vol 93 (3) ◽

pp. 876-880 ◽

Cited By ~ 31

Author(s):

A. Lapolla ◽

M. G. Dalfrà ◽

G. Mello ◽

E. Parretti ◽

R. Cioni ◽

...

Keyword(s):

Insulin Resistance ◽

Insulin Sensitivity ◽

Glucose Tolerance ◽

Early Pregnancy ◽

Cell Function ◽

Late Pregnancy ◽

Tolerance Test ◽

Oral Glucose ◽

Β Cell ◽

Β Cell Function

Abstract Objective: Insulin sensitivity and secretion during early and late pregnancy were assessed in women with normal glucose tolerance and gestational diabetes mellitus (GDM). Research Design and Methods: The oral glucose tolerance test (OGTT) was performed in 903 women at 16–20th gestational week, of whom 37 had GDM (GDM1 group), and 859 repeated the OGTT at wk 26–30. At the second test, 55 had GDM (GDM2 group); the others remained normotolerant (ND group). Insulin sensitivity from OGTT (as quantitative insulin sensitivity check index and OGTT insulin sensitivity) and β-cell function (as the ratio of the areas under the insulin and glucose concentration curves, adjusted for insulin sensitivity) were assessed in both tests. Results: In early pregnancy the quantitative insulin sensitivity check index was not different in the three groups, whereas OGTT insulin sensitivity was lowest in GDM2, intermediate in GDM1, and highest in ND. In late pregnancy both indices were reduced in GDM compared with ND and lower than in early pregnancy. In early pregnancy GDM1, but not GDM2, had lower β-cell function than ND. During the late visit, GDM2 also showed impaired β-cell function compared with ND; furthermore, the adaptation to the increase to insulin resistance from early to late pregnancy was defective in GDM2. Conclusions: In early pregnancy insulin sensitivity, as assessed from the OGTT but not from fasting measurements, is impaired in women who developed GDM. β-Cell function impairment is evident only when GDM is manifest and is characterized by inappropriate adaptation to the pregnancy induced increase in insulin resistance.

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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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