title: The role of serum magnesium and calcium on the association between adiponectin levels and all-cause mortality in end-stage renal disease patients.
abstract: BACKGROUND
  Adiponectin (ADPN) is the most abundant adipocyte-specific cytokine that plays an important role in energy homeostasis by regulating lipid and glucose metabolism. Studies of the impact of ADPN on clinical outcomes have yielded contradictory results so far. Here, we examined the association of ADPN with serum magnesium (s-Mg) and calcium (s-Ca) levels and explored the possibility whether these two factors could modify the relationship between ADPN and all-cause mortality in patients with end-stage renal disease.
  
  
  RESULTS
  After baseline assessment, 47 hemodialysis and 27 peritoneal dialysis patients were followed- up for a median period of 50 months. S-Mg and s-Ca levels emerged as positive and negative predictors of ADPN levels, respectively. During the follow-up period 18 deaths occurred. There was a significant 4% increased risk for all-cause mortality for each 1-µg/ml increment of ADPN (crude HR, 1.04; 95% CI, 1.01-1.07), even after adjustment for s-Mg and s-Ca levels, dialysis mode, age, albumin and C-reactive protein. Cox analysis stratified by s-Mg levels (below and above the median value of 2.45 mg/dl) and s-Ca levels (below and above the median value of 9.3 mg/dl), revealed ADPN as an independent predictor of total mortality only in the low s-Mg and high s-Ca groups. Furthermore, low s-Mg and high s-Ca levels were independently associated with malnutrition, inflammation, arterial stiffening and risk of death.
  
  
  CONCLUSIONS
  The predictive value of ADPN in all-cause mortality in end-stage renal disease patients appears to be critically dependent on s-Mg and s-Ca levels. Conversely, s-Mg and s-Ca may impact on clinical outcomes by directly modifying the ADPN's bioactivity.
authors.affiliation: Department of Nutrition and Dietetics, Technological Educational Institute of Crete, Crete, Greece.
authors.forename: Anastasia
authors.initials: A
authors.lastname: Markaki
authors.forename: John
authors.initials: J
authors.lastname: Kyriazis
authors.forename: Kostas
authors.initials: K
authors.lastname: Stylianou
authors.forename: George A
authors.initials: GA
authors.lastname: Fragkiadakis
authors.forename: Kostas
authors.initials: K
authors.lastname: Perakis
authors.forename: Andrew N
authors.initials: AN
authors.lastname: Margioris
authors.forename: Emmanuel S
authors.initials: ES
authors.lastname: Ganotakis
authors.forename: Eugene
authors.initials: E
authors.lastname: Daphnis
mesh_terms: D052242:Adiponectin / Q000097:blood*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001823:Body Composition / Q000502:physiology; D002118:Calcium / Q000097:blood*; D005260:Female; D006801:Humans; D007676:Kidney Failure, Chronic / Q000097:blood* / Q000401:mortality*; D008274:Magnesium / Q000097:blood*; D008297:Male; D008875:Middle Aged; D055815:Young Adult
chemical_list: D052242:Adiponectin; D008274:Magnesium; D002118:Calcium