Article

Impact of metformin versus repaglinide on non-glycaemic cardiovascular risk markers related to inflammation and endothelial dysfunction in non-obese patients with type 2 diabetes.

Steno Diabetes Center, Niels Steensens Vej 2, 2820 Gentofte, Denmark.
European Journal of Endocrinology (impact factor: 3.42). 05/2008; 158(5):631-41. DOI:10.1530/EJE-07-0815
Source: PubMed

ABSTRACT In patients with type 2 diabetes mellitus (T2DM), biomarkers reflecting inflammation and endothelial dysfunction have been linked to cardiovascular disease (CVD biomarkers) and metabolic regulation. In T2DM patients, metformin and insulin secretagogues have demonstrated equal anti-hyperglycaemic potency. Here, we report the effect of metformin versus an insulin secretagogue, repaglinide, on CVD biomarkers in non-obese T2DM patients.
Single-centre, double-masked, double-dummy, crossover study during 2x4 months involving 96 non-obese (body mass index< or =27 kg/m(2)) insulin-naïve T2DM patients. At enrolment, previous oral hypoglycaemic agents were stopped and the patients entered a 1-month run-in on diet-only treatment. Hereafter, patients were randomized to either 2 mg repaglinide thrice daily followed by 1 g metformin twice daily or vice versa each during 4 months with a 1-month washout between interventions.
Levels of tumour necrosis factor-alpha, plasminogen activator inhibitor-1 antigen, tissue-type plasminogen activator antigen, von Willebrand factor, soluble intercellular adhesion molecule-1 and soluble E-selectin were significantly lower during metformin versus repaglinide treatments. In contrast, Amadori albumin and heart rate were higher during metformin versus repaglinide. Levels of interleukin-6, fibrinogen, soluble vascular cell adhesion molecule-1, asymmetric dimethylarginine and advanced glycation end products as well as glycaemic levels (previously reported) and 24-h blood pressure were similar between treatments. Adjustment for known macrovascular disease did not affect the between-treatment effects.
In non-obese T2DM patients, metformin was more effective in reducing selected biomarkers reflecting inflammation and endothelial dysfunction compared with repaglinide despite similar glycaemic levels between treatments.

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Keywords

1 g metformin
 
1-month run-in
 
2 mg repaglinide thrice
 
2x4 months
 
4 months
 
asymmetric dimethylarginine
 
body mass index<
 
cardiovascular disease
 
diet-only treatment
 
endothelial dysfunction
 
equal anti-hyperglycaemic potency
 
glycation end products
 
insulin secretagogue
 
insulin secretagogues
 
macrovascular disease
 
plasminogen activator inhibitor-1 antigen
 
previous oral hypoglycaemic agents
 
soluble E-selectin
 
tissue-type plasminogen activator antigen
 
tumour necrosis factor-alpha