Chronic kidney disease patients who smoke have higher serum phosphorus

J Bras Nefrol. 2019 Apr-Jun;41(2):288-292. doi: 10.1590/2175-8239-JBN-2018-0156. Epub 2018 Dec 10.
[Article in English, Portuguese]

Abstract

Introduction: Mineral and bone metabolism disorders in chronic kidney disease (CKD-MBD) constitute a syndrome defined by changes in calcium, phosphorus (P), vitamin D and parathormone, fibroblast growth factor 23 (FGF-23) and its specific cofactor, Klotho. CKD-MBD, as well as smoking, are associated with an increased risk of cardiovascular disease. However, it is not known whether or not smoking impacts the cardiovascular risk in CKD- MBD.

Objective: To analyze the relationship between smoking and CKD-MBD markers.

Methods: We evaluated 92 patients divided into: 1) Control Group: non-smokers without CKD; 2) CKD group in stages III and IV under conservative treatment (20 non-smokers and 17 smokers); 3) CKD group on dialysis (21 non-smokers and 19 smokers). Clinical, demographic, and biochemical markers were compared between the groups.

Results: FGF-23 and Klotho levels were not different between smokers and non-smokers. Patients in the CKD group on conservative treatment had higher serum P than non-smokers (p = 0.026) even after adjusted for renal function (p = 0.079), gender (p = 0.145) and age (p = 0.986).

Conclusion: Smoking confers a higher cardiovascular risk to CKD patients under conservative treatment as it is associated with higher levels of P. Further studies are needed to confirm and better elucidate this finding.

MeSH terms

  • Adult
  • Age Factors
  • Aged
  • Bone Diseases, Metabolic / blood*
  • Cardiovascular Diseases / etiology
  • Conservative Treatment
  • Cross-Sectional Studies
  • Female
  • Ferritins / blood
  • Fibroblast Growth Factor-23
  • Fibroblast Growth Factors / blood
  • Glucuronidase / blood
  • Humans
  • Klotho Proteins
  • Male
  • Middle Aged
  • Parathyroid Hormone / blood
  • Phosphorus / blood*
  • Renal Dialysis
  • Renal Insufficiency, Chronic / blood*
  • Renal Insufficiency, Chronic / therapy
  • Risk Factors
  • Smoking / adverse effects
  • Smoking / blood*
  • Smoking / mortality
  • Vitamin D / blood

Substances

  • FGF23 protein, human
  • PTH protein, human
  • Parathyroid Hormone
  • Vitamin D
  • Phosphorus
  • Fibroblast Growth Factors
  • Fibroblast Growth Factor-23
  • Ferritins
  • Glucuronidase
  • Klotho Proteins