title: Unchanged hypovitaminosis D and secondary hyperparathyroidism in morbid obesity after bariatric surgery.
abstract: BACKGROUND
  Morbidly obese patients have been reported to present with vitamin D insufficiency and secondary hyperparathyroidism. We assessed whether bariatric surgery alters the 25-hydroxyvitamin D (calcidiol) and intact parathyroid hormone (iPTH) levels in patients presenting with morbid obesity.
  
  
  METHODS
  A cross-sectional survey was conducted on 144 patients of whom 80 had not undergone bariatric surgery, while 64 had bariatric surgery at a mean of 36 months previously. Calcidiol levels were defined as being normal (>50 nmol/L), insufficient (2550 nmol/L) and deficient (<25 nmol/L). Mild secondary hyperparathyroidism was defined as iPTH >7.3 pmol/L with simultaneous normal values for creatinine, calcium and phosphorus.
  
  
  RESULTS
  80% of the patients presented low vitamin D levels and mild secondary hyperparathyroidism. Previous surgery or the presence of diabetes did not influence calcidiol levels. Corrected serum calcium, phosphorus, alkaline phosphatase, iPTH and Calcidiol were similar between subjects with and without surgery.
  
  
  CONCLUSIONS
  Vitamin D deficient states with secondary hyperparathyroidism in the morbidly obese precede and are not significantly affected by bariatric surgery. Hypovitaminosis D with secondary hyperparathyroidism due to low calcidiol bio-availability should be added to the crowded list of sequelae of morbid obesity. While further studies are warranted, it seems advisable to support vitamin D supplementation in the morbidly obese population.
authors.affiliation: Department of Endocrinology, Hospital de Sant Pau, Barcelona, Spain. juanybarra@hotmail.com
authors.forename: Juan
authors.initials: J
authors.lastname: Ybarra
authors.forename: Joan
authors.initials: J
authors.lastname: Sánchez-Hernández
authors.forename: Ignasi
authors.initials: I
authors.lastname: Gich
authors.forename: Alberto
authors.initials: A
authors.lastname: De Leiva
authors.forename: Xavier
authors.initials: X
authors.lastname: Rius
authors.forename: Jose
authors.initials: J
authors.lastname: Rodríguez-Espinosa
authors.forename: Antonio
authors.initials: A
authors.lastname: Pérez
mesh_terms: D000328:Adult; D000469:Alkaline Phosphatase / Q000097:blood; D049088:Bariatrics; D015992:Body Mass Index; D002112:Calcifediol / Q000097:blood; D002118:Calcium / Q000097:blood; D003404:Creatinine / Q000097:blood; D003430:Cross-Sectional Studies; D048909:Diabetes Complications; D005260:Female; D005500:Follow-Up Studies; D015390:Gastric Bypass; D006801:Humans; D006962:Hyperparathyroidism, Secondary / Q000209:etiology*; D008297:Male; D009767:Obesity, Morbid / Q000097:blood / Q000150:complications* / Q000601:surgery; D010281:Parathyroid Hormone / Q000097:blood; D010758:Phosphorus / Q000097:blood; D014808:Vitamin D Deficiency / Q000209:etiology*; D015431:Weight Loss
chemical_list: D010281:Parathyroid Hormone; D010758:Phosphorus; D003404:Creatinine; D000469:Alkaline Phosphatase; D002112:Calcifediol; D002118:Calcium