Association between cardiorespiratory fitness and impaired vascular function in type 2 diabetes

BACKGROUND Cardiorespiratory fitness (CRF) is inversely associated with the risk of cardiovascular disease, which is related to impaired vascular function. However, its relationship with vascular function remains unknown in patients with type 2 diabetes. AIM To assess the relationship of CRF with vascular function in type 2 diabetes. METHODS Patients with type 2 diabetes who were aged ≥ 18 years and underwent an incremental and symptom-limited exercise test were included. Vascular function was assessed by the construction of the vascular health index (VHI), which is defined as a composite score of ankle-brachial index, transcutaneous oxygen pressure, pulse wave velocity, and carotid intima-media thickness. Impaired vascular function is defined as a VHI of < 8 points. Linear and logistic regression analyses were used to assess the associations. RESULTS We included 343 patients with type 2 diabetes. CRF was positively correlated with VHI (β = 0.10, P = 0.047), particularly with ankle-brachial index and pulse wave velocity. The odds ratio (OR) of impaired vascular function was 0.44 [95% confidence interval (CI): 0.20-0.96] for the highest vs the lowest CRF category. For each one metabolic equivalent increase in CRF, the OR of impaired vascular function was 0.73 (95%CI: 0.57-0.93). CONCLUSION Higher CRF was associated with better vascular function and lower odds of impaired vascular function in patients with type 2 diabetes.