Association of cardiorespiratory fitness with retinal vessel diameters as a biomarker of cardiovascular risk.

OBJECTIVE: We aimed to investigate the association of retinal microvascular health with cardiorespiratory fitness (VO2peak) and cardiovascular risk factors. METHODS: In a population of 260 obesity-enriched participants we investigated the association of retinal vessel diameters with cardiorespiratory fitness (CRF), body mass index (BMI) and blood pressure (BP). Retinal vessel imaging was performed by use of a fundus camera and a semi-automated processing software, calculating the central retinal arteriolar (CRAE) and venular equivalent (CRVE) as well as the arteriolar-to-venular diameter ratio (AVR). RESULTS: Participants had a mean age of 45.8 ±â€¯12.5 years and a BMI of 35.8 ±â€¯6.8 kg/m2. 45% of patients were diagnosed with hypertension, 26% with diabetes and 30% with dyslipidemia. Increasing VO2peak was independently associated with lower CRVE (ß = -0.600; CI -1.141, -0.060; p = 0.030). Higher BMI and mean arterial pressure were independently associated with narrower CRAE (ß = -0.492; CI -0.909, -0.076; p = 0.021 and ß = -0.268; CI -0.471, -0.066; p = 0.009, respectively) and lower AVR (ß = -0.002; CI -0.003, -0.000; p = 0.026 and ß = -0.001; CI -0.002, -0.000; p = 0.001, respectively). CONCLUSIONS: Higher cardiorespiratory fitness is associated with beneficial retinal microvascular health. Higher BMI and BP were associated with an impairment of retinal microvascular health. Exercise is known for its potential to improve body composition and reduce BP but may also prove to be an efficient therapy to counteract small vessel disease in cardiometabolic disease.