Impaired Retinal Vasoreactivity: An Early Marker of Stroke Risk in Diabetes

Area of Science:

• Ophthalmology
• Neurology
• Endocrinology

Background:

• Diabetes mellitus is a major risk factor for cerebrovascular diseases, including stroke and vascular dementia.
• Assessing the brain's microvasculature is challenging, unlike larger cerebral vessels.
• Previous research linked retinal vessel changes to stroke risk, but these appear late in the disease process.

Purpose of the Study:

• To investigate if retinal vascular status can predict early-stage cerebral small vessel dysfunction in diabetes.
• To explore the relationship between retinal and cerebral vascular function in individuals with prediabetes and type-2 diabetes.

Main Methods:

• Employed a noninvasive retinal imaging device (Dynamic Vessel Analyzer) to measure retinal vasoreactivity.
• Utilized transcranial Doppler studies to assess cerebral vascular function.
• Studied 78 participants: 19 healthy controls, 22 with prediabetes, and 37 with type-2 diabetes.

Main Results:

• Cerebral blood vessel responsiveness declined with increasing diabetes severity.
• Retinal vascular reactivity was significantly reduced in prediabetes and diabetes groups compared to controls.
• Impaired cerebral vasoreactivity in diabetic subjects was associated with attenuated retinal venous flicker response.

Conclusions:

• This study establishes a link between retinal and cerebral vascular function in diabetes.
• Attenuated retinal venous responsiveness may serve as an early indicator of vascular dysfunction in diabetes.
• This early marker could potentially predict the risk of stroke and vascular dementia.