The effect of vitamin D supplementation on glycemic status of elderly people with prediabetes: a 12-month open-label, randomized-controlled study

ABSTRACT

Background

Data on the efficacy of vitamin D in improving the glycemic status of elderly people with prediabetes are scarce. This open-label, randomized-controlled trial investigated the effect of vitamin D supplementation on glycemic markers of Greek people with prediabetes aged 60 years or above, over 12 months.

Research design and methods

Participants were randomized to a weekly vitamin D₃ dose of 25,000 IU (n = 45) or nothing (n = 45), on top of lifestyle measures. Anthropometric and glycemic markers were assessed at baseline, 3, 6, and 12 months

Results

Supplemented participants demonstrated a significant increase in 25(OH)D concentrations at 3,      6,      and 12 months     compared to baseline    . In the intervention group, fasting glucose was decreased at 6 months compared to baseline (96.12 ± 5.51 vs 103.40 ± 12.05 mg/dl, p < 0.01) and glycated hemoglobin was significantly lower at 6 and 12 months compared to baseline [5.82 ± 0.21% vs 5.87 ± 0.21%, p = 0.004 and 5.80 ± 0.23% vs 5.87 ± 0.21%, p < 0.001, respectively].

Conclusions

Vitamin D could be complementary to lifestyle change strategy for the management of prediabetes in the elderly.

Clinical trial registration

ISRCTN51643592.

KEYWORDS:

• Prediabetes
• vitamin D
• older adults
• insulin resistance

Supplementary material

Supplemental data for this article can be accessed here

Acknowledgments

The authors thank the participants in the present study for their cooperation.

Author contributions

K Kotsa, I Iakovou and A Gotzamani-Psarrakou conceptualized and designed the study. E Zaromytidou, D Drivakou, S Konstantinidou, V Antonopoulou, M Grammatiki and E Manthou collected all data. G Dimakopoulos performed the statistical analysis. E Zaromytidou, T Koufakis, G Dimakopoulos and K Kotsa analyzed and interpreted the results. E Zaromytidou, T Koufakis and G Dimakopoulos performed the literature review and drafted the first version of the manuscript. All authors have read and critically revised the manuscript and approved the final version.

Consent to participate

Written informed consent was obtained from all participants.

Declaration of interest

The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.

Ethics approval

The research protocol was approved by the Ethics Committee of the Aristotle University of Thessaloniki (approval number: 260/19-04-16).

Reviewer disclosures

Peer reviewers on this manuscript have no relevant financial or other relationships to disclose.

Supplememtary material

Supplemental data for this article can be accessed here