Avaliação dos efeitos do fumo sobre os marcadores do metabolismo mineral em pacientes com doença renal crônica

Abstract

Introduction: Chronic kidney disease is a highly prevalent disease, considered a public health problem. Disorders of mineral and bone metabolism of chronic kidney disease (CKD-BMD) is defined as changes in serum calcium (Ca), phosphorus (P), vitamin D, parathyroid hormone (PTH), fibroblast growth factor 23 (FGF-23) and Klotho, which is a specific FGF-23 cofactor. Both CKD-MBD and smoking habits are associated with an increased risk of cardiovascular disease. However, there is no study, so far, that has evaluated whether there is an association between CKD-MBD and smoking. Objective: To analyze the relationship between smoking habits, chronic kidney disease and serum levels of FGF-23, Klotho and hypoxia induced event (HIF-1α). Methods: We have evaluated 92 patients divided into three groups: Control without CKD, CKD stages III and IV on conservative treatment, and dialytic group, with smokers and non-smokers. We collected data from August 2016 to January 2017. Measurements of HIF-1α, and Klotho were performed using commercial ELISA assays, and FGF-23 assays by chemiluminescence according to the manufacturers protocols. Results: Patients on dialysis performed less time of physical activity than the other groups. P was higher among patients on conservative treatment with smoking habits; serum uric acid level was lower in smokers, regardless the group. FGF-23 was higher in dialysis patients than in conservative patients. There were no differences in Klotho and HIF1α levels among groups. Conclusion: Our results did not show differences in FGF-23 levels when comparing patients with and without smoking habits, but the finding of lower serum uric acid and higher serum phosphate in smokers is new. Considering that, further studies are necessary to a better understanding of the role of smoking on serum phosphate and uric acid.