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Retinal vessel diameters and reactivity in diabetes mellitus and/or cardiovascular disease
R Heitmar1, G Y H Lip2,3, R E Ryder4
1School of Life and Health Sciences, Aston University, Aston Triangle, Birmingham, B4 7ET, UK. r.heitmar1@aston.ac.uk.
Insights
Dynamic retinal vascular measurements using flicker light can differentiate between diabetes mellitus and cardiovascular disease. Reduced arterial constriction in diabetes patients may serve as a progression marker.
Area of Science:
- Ophthalmology
- Cardiology
- Endocrinology
Background:
- Retinal vessel calibre and reactivity to flicker light may distinguish patients with diabetes mellitus (DM) and/or cardiovascular disease (CVD).
- Assessing dynamic retinal vascular responses offers potential for early disease detection and monitoring.
Purpose of the Study:
- To investigate dynamic retinal vascular responses to flicker light provocation in patients with DM, CVD, or both.
- To determine if retinal vascular measurements can differentiate between these patient groups and serve as a disease progression marker.
Main Methods:
- 116 patients with DM, CVD, or both underwent systemic and intraocular pressure measurements.
- Retinal vessel calibres were assessed using a computer-based program (CRVE).
- Vessel dilation/constriction responses to flicker light were recorded continuously; plasma endothelial markers (vWf, sEsel) were measured.
Main Results:
- Retinal vessel calibres were similar across groups, but CRVE correlated with disease duration in DM patients.
- DM patients showed reduced arterial vasomotion and constriction compared to CVD patients.
- CVD+DM patients exhibited inconsistent arterial constriction and dilation patterns between flicker cycles; elevated vWf and sEsel levels were observed.
Conclusions:
- Dynamic retinal vascular measurements via flicker light reveal subtle differences between CVD patients with and without DM.
- The distinct reaction patterns and lack of arterial constriction in DM patients may serve as a marker for monitoring disease progression.
Background:
Retinal vessel calibre and vascular dilation/constriction in response to flicker light provocation may provide a measure distinguishing patients suffering from diabetes mellitus and/or cardiovascular disease.
Methods:
One hundred and sixteen age and sex matched patients with diabetes mellitus (DM), cardiovascular disease (CVD) and both DM and CVD (DM + CVD) underwent systemic and intraocular pressure measurements. Retinal vessel calibres were assessed using a validated computer-based program to compute central retinal artery and vein equivalents (CRVE) from monochromatic retinal images. Vessel dilation and constriction responses to flicker light provocation were assessed by continuous retinal vessel diameter recordings. Plasma endothelial markers von Willebrand factor (vWf) and soluble E selectin (sEsel) were measured by ELISA.
Results:
Retinal vessel calibres were comparable across groups but CRVE correlated significantly with disease duration in DM patients (r = 0.57, p < 0.001). Patients suffering DM only exhibited reduced arterial vasomotion at rest and reduced arterial constriction following flicker light induced vessel dilation compared to patients with CVD and those suffering both CVD + DM (p = 0.030). Patients suffering from CVD + DM exhibited significant differences between each flicker cycle in regards to arterial maximum constriction (p = 0.006) and time needed to reach arterial maximum dilation (p = 0.004), whereas the other two groups did not show such inconsistencies between individual flicker cycles. vWf was raised in CVD + DM compared to the other two groups (p ≤ 0.02), whilst sEsel was raised in CVD + DM compared to DM alone (p = 0.044).
Conclusions:
Dynamic retinal vascular calibres as obtained by continuous diameter measurements using flicker light provocation can reveal subtle differences between groups suffering from CVD with and without DM. This difference in reaction pattern and lack of arterial constriction in DM may provide a suitable marker to monitor progression.
