Intensive insulin therapy improves endothelial function and microvascular reactivity in young people with type 1 diabetes

Diabetologia. 2008 Feb;51(2):353-60. doi: 10.1007/s00125-007-0870-2. Epub 2007 Nov 27.

Abstract

Aims/hypothesis: Macrovascular disease is an important cause of the increased morbidity and mortality rates associated with type 1 diabetes, and this vascular impairment begins in childhood. The aim of this study was to determine whether introducing intensive diabetes management [intensive insulin therapy (IIT) and 'Sweet Talk' text-messaging support] produces measurable improvements in endothelial function.

Methods: One hundred and twenty-six patients fulfilled the eligibility criteria (type 1 diabetes for >1 year; on conventional insulin therapy (CIT); aged between 8 and 18 years), of whom 92 enrolled. Patients were randomised to group 1, CIT only (n=28); group 2, CIT and Sweet Talk (n=33); or group 3, IIT and Sweet Talk (n=31). Vascular assessments (including measures of endothelial damage, activation, dysfunction and oxidative stress) and HbA1c were performed at baseline and repeated after 12 months of the study.

Results: Glycaemic control deteriorated in patients on CIT, but improved significantly in patients allocated to IIT (p=0.007). IIT was associated with significantly greater improvements in E-selectin (p<0.0001) than CIT (group 1, p=0.026 and group 2, p=0.053). Vascular responses to acetylcholine improved in patients on IIT (p=0.017), but not in patients receiving CIT. These changes were all independent of HbA1c level.

Conclusions/interpretation: IIT appears to be associated with improvements in vascular markers, independently of changes in HbA1c, suggesting that IIT may confer vascular protection in addition to improving glycaemic control.

Publication types

  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Blood Glucose / analysis
  • Child
  • Diabetes Mellitus, Type 1 / blood
  • Diabetes Mellitus, Type 1 / complications*
  • Diabetic Angiopathies / drug therapy*
  • Diabetic Angiopathies / etiology
  • Diabetic Angiopathies / physiopathology
  • Endothelium / drug effects*
  • Endothelium / metabolism
  • Endothelium / physiopathology
  • Female
  • Glycated Hemoglobin / analysis
  • Humans
  • Hypoglycemic Agents / therapeutic use
  • Insulin / therapeutic use*
  • Lipid Metabolism / drug effects
  • Male
  • Microcirculation / drug effects*
  • Treatment Outcome

Substances

  • Blood Glucose
  • Glycated Hemoglobin A
  • Hypoglycemic Agents
  • Insulin