In 1515 subjects (753 females) from the population-based Study of Health in Pomerania, the relationship between flow-mediated vasodilatation of the brachial artery (cuff occlusion of the forearm for 5 min) and glomerular filtration rate, estimated on the basis of serum cystatin C levels, was analyzed under consideration of various cardiovascular risk factors.
Flow-mediated vasodilatation was 5.75 ± 0.16 % in women and 4.29 ± 0.12 % in men (mean ± SEM). Glomerular filtration rate amounted to 94.2 ± 0.7 ml/min/1.73 m2, with 8.1 % subjects with glomerular filtration rate ≤ 60 ml/min/1.73 m2. Flow-mediated vasodilatation significantly correlated with glomerular filtration rate in the entire population (r = 0.237, p < 0.001), in women (r = 0.224, p < 0.001) and in men (r = 0.168, p < 0.001). Adjusting for age and multiple cardiovascular risk factors and also for high-sensitive C-reactive protein levels revealed a significant association of flow-mediated vasodilatation and glomerular filtration rate in women (p = 0.01), but not in men, with similar results when the analyses were restricted to individuals with glomerular filtration rate >60 ml/min/1.73 m2.
Mild reduction in renal function is associated with alterations in endothelial function in females. Hence, very mild alterations in kidney function may also be regarded as a cardiovascular risk factor at least in women.