In:
BMJ Open, BMJ, Vol. 11, No. 6 ( 2021-06), p. e045415-
Abstract:
The aim of this study was to determine the relationship of haemoglobin A1c (HbA1c) level with flow-mediated vasodilation (FMD) and nitroglycerine-induced vasodilation (NID) in patients with type 2 diabetes. Design Cross-sectional study. Setting 22 university hospitals and affiliated clinics in Japan. Participants 1215 patients with type 2 diabetes including 349 patients not taking antidiabetic drugs. Measures We evaluated FMD and HbA1c level. All patients were divided into four groups based on HbA1c level: 〈 6.5%, 6.5%–6.9%, 7.0%–7.9% and ≥8.0%. Results An inverted U-shaped pattern of association between HbA1c level and FMD was observed at the peak of HbA1c of about 7%. FMD was significantly smaller in the HbA1c 〈 6.5% group than in the HbA1c 6.5%–6.9% group and HbA1c 7.0%–7.9% group (p 〈 0.001 and p 〈 0.001), and FMD values were similar in the HbA1c 〈 6.5% group and HbA1c ≥8.0% group. There were no significant differences in NID values among the four groups. After adjustments for confounding factors, FMD was significantly smaller in the HbA1c 〈 6.5% group than in the HbA1c 6.5%–6.9% and HbA1c 7.0%–7.9% group (p=0.002 and p=0.04). In patients not taking antidiabetic drugs, FMD was also significantly smaller in the HbA1c 〈 6.5% group than in the HbA1c 6.5%–6.9% group and HbA1c 7.0%–7.9% group (p 〈 0.001 and p=0.02), and there were no significant differences in NID values among the four groups. Conclusions These findings suggest that there is an inverted U-shaped pattern of association between FMD and HbA1c and that a low HbA1c level of 〈 6.5% is associated with endothelial dysfunction. Trial registration number UMIN000012950, UMIN000012951, UMIN000012952 and UMIN000003409.
Type of Medium:
Online Resource
ISSN:
2044-6055
,
2044-6055
DOI:
10.1136/bmjopen-2020-045415
Language:
English
Publisher:
BMJ
Publication Date:
2021
detail.hit.zdb_id:
2599832-8
