title: How long is the warranty period for nil or low coronary artery calcium in patients new to hemodialysis?
abstract: BACKGROUND
  Coronary artery calcification (CAC) is common in patients with advanced chronic kidney disease on dialysis. A sizeable proportion of patients has no or minimal CAC at the inception of dialysis, but it is unclear how long they remain free of it.
  
  
  METHODS
  For the purpose of this study, 36 incident hemodialysis patients were submitted to sequential chest computed tomography to quantify CAC at baseline, 6, 12, 18 and 30 months.
  
  
  RESULTS
  Among them, 15 had absent or minimal CAC score (CACS 0 to 30) and 21 had a CACS>30 at baseline. Overall, the median baseline CACS was 129 (interquartile range [IQR]=0-709) and it increased to 364 (IQR=8.3-1683) at study completion (182% increase). Among the 15 patients with minimal CACS, only 3 progressed and the median CACS increase was 20, as opposed to 15 of 21 patients with a baseline CACS>30 whose median progression was 431 (p<0.02). The 18 patients who had CACS progression were older (68.5 vs. 57.3 years, p=0.0081) and exhibited a poorer control of mineral metabolism (phosphorus 5.2 vs. 4.9 mg/ dL, p=0.048; corrected calcium x phosphorus product [CaxP] 49.3 vs. 46.2 mg2/dL2, p=0.001) than the patients without progression. On multivariable analysis, independent predictors of progression were baseline CACS (p=0.038) and time-averaged Cax;P (p=0.077).
  
  
  CONCLUSIONS
  These data suggest that absent or low CAC at baseline is associated with minimal progression even up to 30 months. Careful management of mineral metabolism appears to be one of the main factors that limit progression of CAC.
authors.affiliation: Department of Nephrology, San Paolo Hospital, University of Milan, Milan, Italy.
authors.forename: Antonio
authors.initials: A
authors.lastname: Bellasi
authors.forename: Laura
authors.initials: L
authors.lastname: Kooienga
authors.forename: Geoffrey A
authors.initials: GA
authors.lastname: Block
authors.forename: Emir
authors.initials: E
authors.lastname: Veledar
authors.forename: David M
authors.initials: DM
authors.lastname: Spiegel
authors.forename: Paolo
authors.initials: P
authors.lastname: Raggi
mesh_terms: D000368:Aged; D002114:Calcinosis / Q000209:etiology / Q000378:metabolism / Q000517:prevention & control*; D002118:Calcium / Q000032:analysis / Q000378:metabolism*; D003324:Coronary Artery Disease / Q000209:etiology / Q000378:metabolism / Q000517:prevention & control*; D003331:Coronary Vessels / Q000378:metabolism*; D015314:Dialysis Solutions / Q000737:chemistry* / Q000627:therapeutic use; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007676:Kidney Failure, Chronic / Q000150:complications* / Q000378:metabolism / Q000628:therapy; D008297:Male; D008875:Middle Aged; D006435:Renal Dialysis / Q000379:methods*; D012189:Retrospective Studies; D012307:Risk Factors; D013997:Time Factors; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome
chemical_list: D015314:Dialysis Solutions; D002118:Calcium