title: Sodium and potassium excretion are related to bone mineral density in women with coeliac disease.
abstract: OBJECTIVE
  Women with coeliac disease may have a lower bone mineral density due to the malabsorption of calcium before diagnosis. A high sodium excretion is associated with increased calcium and bone loss. Our aim was to describe the bone mineral density (BMD) and sodium excretion in women with coeliac disease.
  
  
  METHODS
  In a cross-sectional study BMD of the lumbar spine and hip was assessed by dual energy X-ray absorptiometry. Sodium, potassium and calcium excretion were measured from a 24 h urine collection.
  
  
  RESULTS
  In 33 women (51 ± 16 yr) BMD was 1.14 ± 0.19 g/cm(2) and 0.94 ± 0.14 g/cm(2) at the lumbar spine and hip respectively. Age matched Z-scores were -0.1 ± 1.2 and -0.3 ± 1.1 at lumbar spine and hip respectively. Sodium excretion was 107 ± 51 mmol/d; 14 (42%) had a sodium excretion >100 mmol Na/d (145 ± 45 mmol/d). Potassium and calcium excretion were 87 ± 25 mmol/d and 4.1 ± 2.0 mmol/d respectively. In women with Na excretion >100 mmol Na/d, Ca excretion was significantly greater than those with <100 mmol/d (4.9 ± 2.0 vs 3.4 ± 1.8, p < 0.05). Sodium excretion and BMI were positively correlated (r = 0.61, p < 0.001) as were sodium and calcium excretion (r = 0.43, p < 0.05). Sodium excretion was inversely related to femoral neck BMD (t = -2.4 p = 0.023) after adjustment for weight, age, years since diagnosis and potassium excretion. Weight, but no other variable, was a predictor of BMD at the lumbar spine (t = 2.58 p = 0.018).
  
  
  CONCLUSIONS
  Sodium excretion was inversely related and potassium excretion positively related to femoral neck density which was similar to age matched women without coeliac disease.
authors.affiliation: School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, South Australia 5000, Australia. Electronic address: Kirsty.Turner@unisa.edu.au.
authors.forename: Kirsty M
authors.initials: KM
authors.lastname: Turner
authors.affiliation: School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, South Australia 5000, Australia. Electronic address: Peter.Clifton@unisa.edu.au.
authors.forename: Peter M
authors.initials: PM
authors.lastname: Clifton
authors.affiliation: School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, South Australia 5000, Australia. Electronic address: Jennifer.Keogh@unisa.edu.au.
authors.forename: Jennifer B
authors.initials: JB
authors.lastname: Keogh
mesh_terms: D015502:Absorptiometry, Photon / Q000379:methods; D000328:Adult; D000367:Age Factors; D000368:Aged; D015519:Bone Density; D002118:Calcium / Q000378:metabolism / Q000652:urine; D002446:Celiac Disease / Q000150:complications / Q000000981:diagnostic imaging / Q000378:metabolism / Q000473:pathology / Q000652:urine*; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008875:Middle Aged; D011188:Potassium / Q000097:blood* / Q000378:metabolism / Q000652:urine*; D012964:Sodium / Q000378:metabolism / Q000652:urine*; D014930:Women
chemical_list: D012964:Sodium; D011188:Potassium; D002118:Calcium
keywords: Bone mineral density; Coeliac disease; Sodium