Association Of Serum Klotho Level With Vascular Dysfunction In Patients With Chronic Kidney Disease

Objective: To investigate the association of serum Klotho level with vascular dysfunction in patients with chronic kidney disease(CKD).Methods: 107 patients with CKD in our hospital from January 2014 to December 2014 and 20 age and sex-matched healthy controls were enrolled in this study. Serum Klotho levels were measured by ELISA.Flow-mediated dilatation(FMD) and carotid intima-media thickness(cIMT) were determined by Doppler ultrasound. Brachial-ankle pulse wave velocity(baPWV) were measured by a volume plethysmographic apparatus. Abdominal aortic calcification(AAC)was assessed by abdominal lateral X-rays. The difference between CKD patients and healthy people was compared. The relationship between the serum Klotho level and markers of CKD-mineral and bone disorder(CKD-MBD) and vascular dysfunction was investigated.Results: 1. Compared to healthy controls, serum Klotho levels and FMD were significantly lower and cIMT, baPWV and AAC were significantly higher in CKD patients. 2. Serum Klotho levels were negatively correlated with age, and positively correlated with eGFR in CKD patients, and were significantly decreased along with the progression of CKD. 3. Serum Klotho levels were positively correlated with 1,25-dihydroxyvitamin D [1,25-(OH)2-D3] level and fractional excretion of phosphorus(FEP), and negatively correlated with log iPTH in CKD patients. 4. Serum Klotho levels in CKD patients were positively correlated with FMD, and negatively correlated with baPWV, cIMT and AAC scores. 5.The levels of Klotho in patients with FMD≥6.0, baPWV≤1400cm/s, cIMT<1.0mm and AAC=0 were significantly higher than those patients with FMD<6.0, baPWV>1400cm/s, cIMT≥1.0mm and AAC>0. 6.Multivariate Logistic analysis showed that age(OR=3.63, 95%CI: 1.75-8.89, P=0.002), MBP(OR=2.98, 95%CI: 1.45-7.69, P=0.009), albuminuria(OR=1.97, 95%CI: 1.16-3.73, P=0.022)、decreased serum Klotho level(OR=0.60, 95%CI: 0.39-0.98, P=0.008) were the independent predictors of vascular calcification in CKD patients.Conclusions: 1.The serum Klotho levels were significantly lower in CKD patients, and the levels were significantly decreased along with CKD progression. 2. Serum Klotho levels were closely related to age, eGFR, iPTH, 1,25-(OH)2-D3, FEP and signs of vascular dysfunction(including FMD, baPWV, cIMT and AAC scores) in CKD patients. 3. Decreases in serum Klotho levels were the independent predictors of vascular calcification in CKD patients.