Dietary Patterns and Retinal Vessel Caliber in the Irish Nun Eye Study

Area of Science:

• Ophthalmology and Cardiovascular Health
• Nutritional Epidemiology
• Retinal Microvascular Imaging

Background:

• Retinal microvascular abnormalities, including venular widening and arteriolar narrowing, are established indicators of cardiovascular disease (CVD) risk.
• Dietary patterns significantly influence cardiovascular health, yet their association with retinal microvascular status remains underexplored.
• Previous research indicates that specific retinal vessel changes predict conditions like stroke, hypertension, coronary heart disease, and diabetes.

Purpose of the Study:

• To investigate the relationship between dietary patterns (DPs) and retinal vascular caliber (RVC) in a cohort of older women.
• To determine if specific dietary habits are associated with measurable changes in retinal venules and arterioles.
• To assess the impact of a 'healthy' versus an 'unhealthy' dietary pattern on retinal microvascular health.

Main Methods:

• A cross-sectional study involving 1233 older women (mean age 76.3 years) from the Irish Nun Eye Study (INES).
• Retinal vascular caliber (RVC) was quantified using computer-assisted software on digital eye images.
• Dietary patterns were derived using principal component analysis from food frequency questionnaire data, with regression models adjusting for key health and demographic factors.

Main Results:

• Two distinct dietary patterns were identified: a 'healthy' pattern (rich in fruits, vegetables, whole grains, oily fish) and an 'unhealthy' pattern (high in sugar, sweets, chips, high-fat dairy, French fries).
• Adherence to the 'unhealthy' dietary pattern was significantly associated with wider central retinal venular equivalent (CRVE) and narrower central retinal arteriolar equivalent (CRAE).
• No significant association was found between the 'healthy' dietary pattern and retinal vascular caliber.

Conclusions:

• In older women with a restricted lifestyle, an unhealthy dietary pattern is independently linked to adverse retinal microvascular changes.
• Specifically, a diet high in processed and unhealthy foods correlates with venular widening and arteriolar narrowing.
• These findings underscore the critical role of dietary choices in maintaining retinal vascular health and potentially mitigating cardiovascular disease risk.