All of the collected data will be entered into a database. The Statistical Package for the Social Sciences for Windows (SPSS Inc, Chicago, Ill) was used to perform statistical analyses. Baseline demographics, comorbidities, medication, the results of blood biochemistry tests, and parameters that are related to HD adequacy and access function are presented as means, standard deviation and proportions as appropriate. Associations between parameters regarding vascular access dysfunction and the other variables were analyzed using the t-test, one-way analysis of variance, and Pearson's correlation coefficients, as appropriate. P<0.05 was considered to indicate statistical significance.