Email updates

Keep up to date with the latest news and content from Cardiovascular Diabetology and BioMed Central.

Open Access Highly Accessed Original investigation

Vitamin D and 1-hour post-load plasma glucose in hypertensive patients

Angela Sciacqua1, Maria Perticone1, Nadia Grillo1, Tania Falbo1, Giuseppe Bencardino1, Elvira Angotti2, Franco Arturi1, Giuseppe Parlato2, Giorgio Sesti1 and Francesco Perticone1*

Author Affiliations

1 Department of Medical and Surgical Sciences, University Magna Græcia of Catanzaro, V.le Europa 88100, Catanzaro, Italy

2 Clinic Chemical Unit, University Hospital of Catanzaro, Catanzaro, Italy

For all author emails, please log on.

Cardiovascular Diabetology 2014, 13:48  doi:10.1186/1475-2840-13-48

Published: 20 February 2014

Abstract

Background

A plasma glucose value ≥155 mg/dl for 1-hour post-load plasma glucose during an oral glucose tolerance test (OGTT) is able to identify subjects with normal glucose tolerance (NGT) at high-risk for type-2 diabetes and with subclinical organ damage. We designed this study to address if 25-hydroxyvitamin D [25(OH)D] circulating levels are associated with glucose tolerance status, and in particular with 1-hour post-load plasma glucose levels.

Methods

We enrolled 300 consecutive Caucasian hypertensive never-treated outpatients (160 men and 140 women, aged 52.9 ± 9.2 years). Subjects underwent OGTT and measurements of 25(OH)D and standard laboratory tests. Estimated glomerular filtration rate (e-GFR) was calculated by CKD-EPI formula and insulin sensitivity was assessed by Matsuda-index.

Results

Among participants, 230 were NGT, 44 had impaired glucose tolerance (IGT) and 26 had type-2 diabetes. According to 1-h post-load plasma glucose cut-off point of 155 mg/dL, we divided NGT subjects into: NGT < 155 (n = 156) and NGT > 155 mg/dL (n = 74).

NGT ≥ 155 had higher significant fasting and post-load glucose and insulin, parathyroid hormone and hs-CRP levels than NGT < 155. On the contrary, Matsuda-index, e-GFR, and 25(OH)D were significantly lower in NGT ≥ 155 than NGT < 155 subjects. In the multiple regression analysis, 25(OH)D levels resulted the major determinant of 1-h post-load plasma glucose in all population and in the four groups of glucose tolerance status. In the whole population, Matsuda-index, hs-CRP and e-GFR explained another 12.2%, 6.7% and 1.7% of its variation.

Conclusions

Our data demonstrate a significant and inverse relationship between 25(OH)D levels and glucose tolerance status, particularly with 1-h post-load glucose.

Keywords:
Vitamin D; Glucose tolerance; Insulin resistance