REWARD: Using the REtina as a Window To Detect Cardiac microvasculAR Dysfunction In Diabetes Mellitus

Study Overview
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Brief Summary
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Retinopathy may be associated with diastolic dysfunction and/or coronary flow reserve in the heart, and albuminuria in diabetic patients. The objective of this study is to examine the cross-sectional relationships of retinopathy with indices of left ventricular diastolic function, coronary flow reserve and urinary albumin excretion, among diabetic patients.

Detailed Description
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Diabetes is a potent risk factor for macrovascular coronary disease, leading to systolic dysfunction and heart failure. More recently diabetic microvascular disease has been recognized to play a key role in the development of diastolic dysfunction and heart failure with preserved ejection fraction. A new paradigm in diabetic heart disease centers on microvascular endothelial dysfunction involving the intra-myocardial capillaries and leading to cardiomyocyte dysfunction and diastolic dysfunction. This is analogous to the microvascular dysfunction well-described in the diabetic retinopathy and nephropathy. Yet, whereas diabetic retinal screening for retinopathy and screening for microalbuminuria are routine, diabetic cardiac screening for microvascular dysfunction is practically non-existent. The retinal vasculature may represent a window of opportunity to detect concurrent microvascular disease in the heart and kidneys before the onset of clinical symptoms. However, there are limited studies that directly attempt to correlate retinopathy to diastolic dysfunction and microalbuminuria. Hence this study aims to examine the cross-sectional relationships of retinopathy with indices of left ventricular diastolic function, coronary flow reserve and urinary albumin excretion, among diabetic patients.

Official Title
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Using the REtina as a Window To Detect Cardiac microvasculAR Dysfunction In Diabetes Mellitus

Conditions
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Retinopathy, Diabetic, Diastolic Dysfunction, Microalbuminuria

Intervention / Treatment
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* Diagnostic Test: Cardiac Assessments and Eye Assessments


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age greater than equal to 21 years old Exclusion Criteria: Known history of active eye lens or corneal opacity Known allergy to eye drops Kidney disease with estimated GFR < 60 Pregnant or lactating women Asthmatic status of the moderate persistent and above categories Chronic obstructive pulmonary disease Thyroid dysfunction

Ages Eligible for Study
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Minimum Age: 21 Years
Maximum Age: 120 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Diseased Group<br>Patients with type 2 diabetic retinopathy and known cardiac dysfunction. | Diagnostic Test: Cardiac Assessments and Eye Assessments<br>* Cardiac Assessments, include the following: transthoracic echocardiography computed tomography of coronary arteries position emission tomography computed tomography or single photon emission tomography computed tomography Eye examinations, include the following: pupil dilation retinal photography dynamic vessel analyser IOL master<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Eye Examination | Retinal photography on diabetic patients will be performed to identify those with retinopathy. | 1 day | 
| Cross-sectional analyses will be performed to look at the association between diabetic retinopathy with left ventricular diastolic function, coronary flow reserve and urinary albumin excretion. | These data will provide initial evidence of the mechanistic link between microvascular dysfunction in the eye, heart and kidneys among patients with diabetes. | 2 days |