The relationship between aortic knob width and various demographic, clinical, and laboratory parameters in stable hemodialysis patients

Abstract

Accelerated atherosclerosis is very common in hemodialysis (HD) patients and is related to morbidity and mortality. The aortic knob width (AKW), which can easily be calculated on chest radiographs has also been found to be related to atherosclerosis in patients with normal renal function. The importance of AKW in HD patients is not known. The current study is aimed to investigate factors associated with increased AKW in HD patients. The study participants had their medical history taken and a physical examination conducted, with calculation of dialysis adequacy and AKW. AKW was calculated from the chest x-rays at the end of the dialysis session, when the patients were in their dry weight. A total of 91 HD patients and 65 patients with normal renal function (as a control group) were included. The mean of the AKW was 35.0 ± 5.8 mm in HD patients and 26.6 ± 4.3 mm in the control group (P <0.0001). Stepwise linear regression analysis of both groups combined revealed that age (P: 0.001), male gender (P <0.0001), systolic BP (P <0.0001), presence of HD treatment (P: 0.016), and albumin levels (P: 0.021) were inde-pendently related with increased AKW. On the other hand, in HD patients stepwise linear regression showed that age (P <0.0001), pre-dialysis systolic BP (P: 0.003), male gender (P <0.0001), being a non-smoker (P: 0.002), total cholesterol (P: 0.001), and intact parathormone levels (P: 0.005) were independently associated with increased AKW. In conclusion, AKW is increased in HD patients when compared with the normal population. These preliminary findings may enhance the use of chest radiography as a screening method, and if confirmed, can assist risk stratification in HD patients.