Effects of vitamin D supplementation on glycated haemoglobin and fasting glucose levels in hypertensive patients: a randomized controlled trial

source extracted confidence: high 2026-04-09
#aged #blood-glucose #dietary-supplements #double-blind-method #fasting

Effects of vitamin D supplementation on glycated haemoglobin and fasting glucose levels in hypertensive patients: a randomized controlled trial

Grübler et al., 2016 | Diabetes Obes Metab | Rct

Citation

Grübler M R, Gaksch M, ... Pilz S. Effects of vitamin D supplementation on glycated haemoglobin and fasting glucose levels in hypertensive patients: a randomized controlled trial. Diabetes Obes Metab. 2016-Oct;18(10):1006-12. doi:10.1111/dom.12709

Abstract

AIM: To investigate the efficacy of vitamin D supplementation on glycaemic control. METHODS: The Styrian Vitamin D Hypertension Trial was a single-centre, double-blind, placebo-controlled study conducted between 2011 and 2014 at the Medical University of Graz, Austria. We enrolled 200 people with arterial hypertension and 25-hydroxyvitamin D [25(OH)D] concentrations <30 ng/mL. Study participants were randomized to receive either 2800 IU of vitamin D or placebo per day for 8 weeks. The present study was a post hoc analysis that incorporated an analysis of covariance (ancova) approach, while adjusting for baseline differences. RESULTS: A total of 185 participants [mean ± standard deviation age, 60.1 ± 11.3 years; 47% women; mean 25(OH)D 21.2 ± 5.6 ng/mL, mean glycated haemoglobin (HbA1c) 44.8 ± 11.8 mmol/mol and mean body mass index 30.4 ± 5.4 kg/m(2) ] completed the trial. ancova showed a mean treatment effect [95% confidence interval (CI)] on HbA1c of -3.52 (-6.7 to -0.34) mmol/mol (p = .045). There was no difference in fasting glucose -4.7 mg/dL (95% CI -16.3 to 6.9; p = .426). CONCLUSIONS: Vitamin D supplementation in obese hypertensive patients with low 25(OH)D reduces HbA1c levels. This finding warrants further investigation into potential vitamin D effects on glucose homeostasis.

Key Findings

A total of 185 participants [mean ± standard deviation age, 60.1 ± 11.3 years; 47% women; mean 25(OH)D 21.2 ± 5.6 ng/mL, mean glycated haemoglobin (HbA1c) 44.8 ± 11.8 mmol/mol and mean body mass index 30.4 ± 5.4 kg/m(2) ] completed the trial. ancova showed a mean treatment effect [95% confidence interval (CI)] on HbA1c of -3.52 (-6.7 to -0.34) mmol/mol (p = .045). There was no difference in fasting glucose -4.7 mg/dL (95% CI -16.3 to 6.9; p = .426).

Outcomes Measured

  • Requires manual extraction

Population

Field Value
Population low 25
Sample Size 200
Age Range See abstract
Condition hypertension

MeSH Terms

  • Aged
  • Blood Glucose
  • Dietary Supplements
  • Double-Blind Method
  • Fasting
  • Female
  • Glycated Hemoglobin
  • Humans
  • Hypertension
  • Male
  • Middle Aged
  • Obesity
  • Vitamin D
  • Vitamin D Deficiency

Evidence Classification

  • Level: Rct
  • Publication Types: Journal Article, Randomized Controlled Trial
  • Vertical: vitamin-d-diabetes

Provenance

Source extracted via PubMed E-utilities API on 2026-04-09