title: Relation between serum calcium, phosphate, parathyroid hormone and 'nondipper' circadian blood pressure variability profile in patients with normal renal function.
abstract: OBJECTIVE
  In patients with renal disease, an association between abnormal circadian blood pressure profile and abnormalities in bone and mineral metabolism, including vascular calcifications, is well known. However, such a link has not yet been reported in hypertensive patients with normal renal function. We aimed to evaluate if higher serum phosphate, calcium, parathyroid hormone (PTH) level and the calcium x phosphate (Ca x P) product would be associated with a nondipper hypertension, in patients with normal renal function and without any PTH disorder.
  
  
  METHODS
  190 hypertensive subjects with the following inclusion criteria were enrolled: (1) normal phosphate and PTH levels; (2) glomerular filtration rate (GFR) >60 ml/min, and (3) no history of calcium, phosphate, vitamin D medication and hyperparathyroidism.
  
  
  RESULTS
  Of the total population, 76 patients (40%) were classified as dippers and 114 (60%) as nondippers. Nondipper patients had higher levels of phosphate (3.70 +/- 0.61 vs. 3.35 +/- 0.44 mg/dl, p = 0.001), Ca x P product (35.4 +/- 6.5 vs. 31.5 +/- 5.0, p = 0.001) and PTH (75.7 +/- 28.8 vs. 46.6 +/- 17.1 pg/ml, p = 0.000) compared to dipper patients. Independent predictors (multiple regression) for nondipper hypertension were PTH (beta = 0.43, p = 0.001) and phosphate (beta = 0.9, p = 0.03).
  
  
  CONCLUSIONS
  We demonstrate a graded independent relation between higher levels of phosphate, PTH, Ca x P product and the risk of nondipping in hypertensive patients with an estimated GFR of >60 ml/min and normal mineral metabolism.
authors: Department of Internal Medicine, Section of Nephrology, Fatih University Faculty of Medicine, Ankara, Turkey. mkanbay@fatih.edu.tr
authors: Mehmet
authors: M
authors: Kanbay
authors: Bunyamin
authors: B
authors: Isik
authors: Ali
authors: A
authors: Akcay
authors: Adem
authors: A
authors: Ozkara
authors: Feridun
authors: F
authors: Karakurt
authors: Faruk
authors: F
authors: Turgut
authors: Rabia
authors: R
authors: Alkan
authors: Ebru
authors: E
authors: Uz
authors: Nuket
authors: N
authors: Bavbek
authors: Ramazan
authors: R
authors: Yigitoglu
authors: Adrian
authors: A
authors: Covic
mesh_terms: D000328:Adult; D000368:Aged; D001794:Blood Pressure; D018660:Blood Pressure Monitoring, Ambulatory; D002118:Calcium / Q000097:blood*; D002940:Circadian Rhythm; D005260:Female; D005919:Glomerular Filtration Rate; D006801:Humans; D006973:Hypertension / Q000097:blood / Q000175:diagnosis / Q000503:physiopathology*; D007668:Kidney / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D010281:Parathyroid Hormone / Q000097:blood*; D010710:Phosphates / Q000097:blood*
chemical_list: C470125:PTH protein, human; D010281:Parathyroid Hormone; D010710:Phosphates; D002118:Calcium