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Retinal haemodynamics in individuals with well-controlled type 1 diabetes

M Lorenzi1, G T Feke, E Cagliero

  • 1Schepens Eye Research Institute and Department of Ophthalmology, Harvard Medical School, and Diabetes Center and Department of Medicine, Massachusetts General Hospital, Boston, MA, USA. mara.lorenzi@schepens.harvard.edu

Diabetologia
|November 21, 2007
PubMed

Insights

Type 1 diabetes patients with good blood sugar control and no retinopathy show normal retinal blood flow. Subtle abnormalities may only appear under stress testing, not at rest.

Area of Science:

  • Ophthalmology
  • Diabetology
  • Vascular Biology

Background:

  • Retinal hemodynamic abnormalities may precede clinical diabetic retinopathy in type 1 diabetes.
  • Good glycemic control, emphasized since the Diabetes Control and Complications Trial (DCCT), influences diabetic retinopathy progression.
  • Investigating early diabetic microangiopathy markers is crucial for disease management.

Purpose of the Study:

  • To assess if type 1 diabetes patients in the post-DCCT era with minimal retinopathy exhibit retinal hemodynamic abnormalities.
  • To determine if current management practices mitigate early vascular changes in the retina.
  • To evaluate retinal blood flow, speed, and arterial diameter in well-controlled type 1 diabetes.

Main Methods:

  • Laser Doppler flowmetry used to measure retinal hemodynamics.
  • Study included 33 type 1 diabetic individuals (no/minimal retinopathy) and 31 controls.
  • Participants excluded vasoactive medications; blood glucose maintained between 3.8-11.1 mmol/l.

Main Results:

  • Type 1 diabetes group had good glycemic control (HbA1c 7.5+/-1.2%).
  • No significant differences in retinal blood speed, arterial diameter, or blood flow were observed between diabetic and control groups.
  • This suggests stable retinal circulation in well-controlled, early-stage type 1 diabetes.

Conclusions:

  • Type 1 diabetes patients with minimal retinopathy and good glycemic control do not display resting retinal hemodynamic abnormalities.
  • Early microvascular changes in the retina may not be detectable at steady state in this cohort.
  • Further studies involving vascular stress tests may be needed to reveal subtle retinal abnormalities.
Abstract

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