Diabetic Retinopathy, Inflammation
Conditions
Keywords
Diabetes mellitus, type 1, Inflammation, Cytokines, Vascular reactivity
Brief summary
There is much evidence that localized low grade inflammatory processes may contribute to the microvascular complications of type 1 and type 2 diabetes mellitus including sight-threatening diabetic retinopathy. Some biomarkers for inflammation have been found to be elevated in diabetes patients and correlations between those biomarkers and the severity of diabetic complications have been found in the last years. The relation between this low grade inflammation and the microvascular changes observed in diabetic retinopathy is, however, not well characterized. In the present study patients with different stages of non-proliferative diabetic retinopathy will be included. Several markers of inflammation will be measured from blood samples. These markers will be related to vascular factors including flicker-induced vasodilatation as a marker of endothelial dysfunction and perifoveal leukocyte velocity and density as measured with the blue field entoptic phenomenon. In addition, the ophthalmologic status of the patients will be assessed according to the Modified Airlie House classification. A multiple regression model will be employed to study the association between the different methods.
Interventions
PROCEDUREBlood sampling
Determination of cytokine plasma levels (ELISA)
PROCEDURENoninvasive measurement of systemic hemodynamics
performed once
PROCEDUREVisual acuity assessment
ETDRS charts
DEVICEBlue field entoptic technique (Blue field stimulator, BFS-2050)
performed once
PROCEDUREOphthalmic examination and fundus photography
7 + 1 standard fields
DEVICERetinal Vessel Analyzer (DVA)
Assessment of retinal vessel reactivity to stimulation with flickering light
DEVICEHigh resolution optical coherence tomography (OCT)
performed once
Sponsors
Medical University of Vienna
Study design
Observational model
COHORT
Time perspective
CROSS_SECTIONAL
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Patients with type 1 diabetes mellitus with duration of \> 1 year * Men and women, age ≥ 18, nonsmokers * Body mass index between 16 and 30 kg/m² * Normal findings in the medical history and physical examination unless the investigator considers an abnormality to be clinically irrelevant or diabetes-related * Mild, moderate or severe non-proliferative diabetic retinopathy
Exclusion criteria
* Abuse of drugs or alcoholic beverages * Participation in a clinical trial in the 3 weeks preceding the study * Treatment with anti-inflammatory drugs in the 3 weeks before the study day * Symptoms of a clinically relevant illness in the 3 weeks before the study day * Blood donation or equivalent blood loss in the 3 weeks before the study day * Other ocular pathologies than non-proliferative diabetic retinopathy * Ametropia \> 6 dpt * History or family history of epilepsy * Pregnant or lactating women
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| Plasma biomarkers for inflammation (CRP, TNF-α, IL-6, vWF, e-Selektin) | 1 day |
| Perifoveal white cell blood flow (Blue field entoptic technique) | 1 day |
| Retinal vessel reactivity to flicker stimulation (Retinal Vessel Analyzer) | 1 day |
| Arteriolar to venous ratio | 1 day |
Secondary
| Measure | Time frame |
|---|---|
| Capillary blood glucose | 1 day |
| Systolic/diastolic arterial blood pressure, pulse rate | 1 day |
| Stage of diabetic retinopathy | 1 day |
| Visual acuity | 1 day |
| Intraocular pressure | 1 day |
Countries
Austria
Outcome results
None listed