May 2008
Volume 49, Issue 13
Free
ARVO Annual Meeting Abstract  |   May 2008
Abnormal Retinal Vascular Reactivity in Response to Posture Change in Well-Controlled Type 1 Diabetic Patients With No Retinopathy
Author Affiliations & Notes
  • G. T. Feke
    Ocular Circulation and Imaging Laboratory, Schepens Retina Associates Foundation, Boston, Massachusetts
    Harvard Medical School, Boston, Massachusetts
  • J. Kolodjaschna
    Ocular Circulation and Imaging Laboratory, Schepens Retina Associates Foundation, Boston, Massachusetts
    Harvard Medical School, Boston, Massachusetts
  • L. Pitler
    Schepens Eye Research Institute, Boston, Massachusetts
  • J. W. McMeel
    Ocular Circulation and Imaging Laboratory, Schepens Retina Associates Foundation, Boston, Massachusetts
    Harvard Medical School, Boston, Massachusetts
  • M. Lorenzi
    Schepens Eye Research Institute, Boston, Massachusetts
    Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts
  • Footnotes
    Commercial Relationships  G.T. Feke, None; J. Kolodjaschna, None; L. Pitler, None; J.W. McMeel, None; M. Lorenzi, None.
  • Footnotes
    Support  Juvenile Diabetes Research Foundation
Investigative Ophthalmology & Visual Science May 2008, Vol.49, 3263. doi:https://doi.org/
  • Views
  • Share
  • Tools
    • Alerts
      ×
      This feature is available to authenticated users only.
      Sign In or Create an Account ×
    • Get Citation

      G. T. Feke, J. Kolodjaschna, L. Pitler, J. W. McMeel, M. Lorenzi; Abnormal Retinal Vascular Reactivity in Response to Posture Change in Well-Controlled Type 1 Diabetic Patients With No Retinopathy. Invest. Ophthalmol. Vis. Sci. 2008;49(13):3263. doi: https://doi.org/.

      Download citation file:


      © ARVO (1962-2015); The Authors (2016-present)

      ×
  • Supplements
Abstract

Purpose: : We recently reported that patients with well-controlled type 1 diabetes with no or minimal retinopathy do not show retinal circulatory abnormalities at steady state. We suggested that it may be necessary to apply a challenge to uncover subtle abnormalities. A change in posture from sitting to lying down produces an increased blood pressure at the entrance to the retinal circulation. We thus tested the retinal vascular response to posture change in a group of patients with the above characteristics.

Methods: : We tested 13 patients with type 1 diabetes and no retinopathy (age 30.7± 9.1 years, mean ± SD, duration of diabetes 12.5 ± 5.9 years, and HbA1c 7.2 ± 0.5%) and 6 healthy control subjects (age 29.0 ± 10.1 years). Arterial diameter, blood speed, and blood flow rate in the superior temporal retinal artery of the left eye were measured first while sitting and then while reclining for approximately 30 minutes using a Canon retinal laser Doppler instrument. Brachial artery blood pressure and heart rate were measured periodically during the test. Nonparametric statistical tests were used in the analysis.

Results: : In the controls, arterial diameter decreased by 5.4 ± 2.2% (p=0.027) and blood speed increased by 16.2 ± 12.3% (p=0.028). The 4.7 ± 12.7% increase in blood flow rate was not significant (p=0.92). In contrast, only 7 of the 13 diabetic patients exhibited a decrease in arterial diameter (5.5 ± 1.6%, p=0.018) while reclining. The remaining 6 failed to show a decrease, instead showing a non-significant increase of 3.1 ± 3.5% (p=0.102). The arterial diameter response to posture change in this subgroup was significantly (p=0.003) different compared to the responses in the other diabetic subgroup and in the controls. This subgroup also failed to show a significant increase in blood speed while reclining (p=0.46). There were no significant differences in age, duration of diabetes, HbA1c, or arterial diameter while sitting between the two subgroups.

Conclusions: : Our results show that the retinal vascular response to posture change is abnormal in a substantial portion of the well-controlled type 1 diabetic patients with no retinopathy that we tested. Studies are in progress to ascertain whether this abnormality in retinal vascular reactivity can be used as a marker for the development of clinical retinopathy and as a surrogate endpoint for preemptive treatments.

Keywords: diabetes • blood supply • diabetic retinopathy 
×
×

This PDF is available to Subscribers Only

Sign in or purchase a subscription to access this content. ×

You must be signed into an individual account to use this feature.

×