title: Determinants of vitamin D levels in children, adolescents, and young adults with juvenile idiopathic arthritis.
abstract: OBJECTIVE
  Deficiency of 25-hydroxyvitamin D [25(OH)D] is reported to be common in patients with rheumatoid arthritis (RA); data in patients with juvenile idiopathic arthritis (JIA) are inconsistent. We assessed serum 25(OH)D in children, adolescents and young adults with JIA, in order to identify the risk factors for vitamin D deficiency in patients with JIA.
  
  
  METHODS
  We evaluated 152 patients with JIA: 115 female, 37 male, mean age 16.2 ± 7.4 yrs; evaluated by onset type, 96 had oligoarticular, 35 polyarticular, 7 systemic, and 14 enthesitis-related arthritis (ERA). Patients were compared with a control group matched for sex and age. All patients and controls underwent laboratory tests of plasma 25(OH)D, parathyroid hormone (PTH), calcium, phosphorus, and bone alkaline phosphatase levels, and dual-energy x-ray absorptiometry examination.
  
  
  RESULTS
  Patients with JIA showed significantly reduced 25(OH)D levels compared to controls (p < 0.001), even divided into subtypes (oligoarticular, p < 0.05; polyarticular, p < 0.005; systemic, p < 0.001; ERA, p < 0.005). Patients with active disease and/or frequent relapses had significantly reduced 25(OH)D levels compared to patients with no active disease and no frequent flares (p < 0.005, respectively). Nevertheless, JIA patients had significantly higher PTH levels compared to controls (p < 0.0001). JIA patients with 25(OH)D deficiency showed a significantly lower bone mineral apparent density than those with normal 25(OH)D levels (p < 0.001).
  
  
  CONCLUSIONS
  JIA patients have reduced 25(OH)D and higher PTH values. This may explain at least in part why JIA patients, despite more effective current drugs, do not achieve bone-normal condition over time. JIA patients with more severe disease could require higher supplementation of vitamin D to maintain normal 25(OH)D serum levels. Longterm studies are needed to investigate the relationship between serum 25(OH)D levels and disease activity in JIA.
authors.affiliation: From the Health Sciences Department, University of Florence, Anna Meyer Children's University Hospital, Florence; Department of BioMedicine, Section of Rheumatology, Transition Clinic, University of Florence, Florence; and Department of Internal Medicine, Endocrinology Unit, University of Florence, Florence, Italy.S. Stagi, MD, Health Sciences Department, University of Florence, Anna Meyer Children's University Hospital; F. Bertini, MD, Department of BioMedicine, Section of Rheumatology, Transition Clinic, University of Florence; L. Cavalli, MD, Department of Internal Medicine, Endocrinology Unit, University of Florence; M. Matucci-Cerinic, MD, Department of BioMedicine, Section of Rheumatology, Transition Clinic, University of Florence; M.L. Brandi, MD, Department of Internal Medicine, Endocrinology Unit, University of Florence; F. Falcini, MD, Department of BioMedicine, Section of Rheumatology, Transition Clinic, University of Florence.
authors.forename: Stefano
authors.initials: S
authors.lastname: Stagi
authors.affiliation: From the Health Sciences Department, University of Florence, Anna Meyer Children's University Hospital, Florence; Department of BioMedicine, Section of Rheumatology, Transition Clinic, University of Florence, Florence; and Department of Internal Medicine, Endocrinology Unit, University of Florence, Florence, Italy.S. Stagi, MD, Health Sciences Department, University of Florence, Anna Meyer Children's University Hospital; F. Bertini, MD, Department of BioMedicine, Section of Rheumatology, Transition Clinic, University of Florence; L. Cavalli, MD, Department of Internal Medicine, Endocrinology Unit, University of Florence; M. Matucci-Cerinic, MD, Department of BioMedicine, Section of Rheumatology, Transition Clinic, University of Florence; M.L. Brandi, MD, Department of Internal Medicine, Endocrinology Unit, University of Florence; F. Falcini, MD, Department of BioMedicine, Section of Rheumatology, Transition Clinic, University of Florence.
authors.forename: Federico
authors.initials: F
authors.lastname: Bertini
authors.affiliation: From the Health Sciences Department, University of Florence, Anna Meyer Children's University Hospital, Florence; Department of BioMedicine, Section of Rheumatology, Transition Clinic, University of Florence, Florence; and Department of Internal Medicine, Endocrinology Unit, University of Florence, Florence, Italy.S. Stagi, MD, Health Sciences Department, University of Florence, Anna Meyer Children's University Hospital; F. Bertini, MD, Department of BioMedicine, Section of Rheumatology, Transition Clinic, University of Florence; L. Cavalli, MD, Department of Internal Medicine, Endocrinology Unit, University of Florence; M. Matucci-Cerinic, MD, Department of BioMedicine, Section of Rheumatology, Transition Clinic, University of Florence; M.L. Brandi, MD, Department of Internal Medicine, Endocrinology Unit, University of Florence; F. Falcini, MD, Department of BioMedicine, Section of Rheumatology, Transition Clinic, University of Florence.
authors.forename: Loredana
authors.initials: L
authors.lastname: Cavalli
authors.affiliation: From the Health Sciences Department, University of Florence, Anna Meyer Children's University Hospital, Florence; Department of BioMedicine, Section of Rheumatology, Transition Clinic, University of Florence, Florence; and Department of Internal Medicine, Endocrinology Unit, University of Florence, Florence, Italy.S. Stagi, MD, Health Sciences Department, University of Florence, Anna Meyer Children's University Hospital; F. Bertini, MD, Department of BioMedicine, Section of Rheumatology, Transition Clinic, University of Florence; L. Cavalli, MD, Department of Internal Medicine, Endocrinology Unit, University of Florence; M. Matucci-Cerinic, MD, Department of BioMedicine, Section of Rheumatology, Transition Clinic, University of Florence; M.L. Brandi, MD, Department of Internal Medicine, Endocrinology Unit, University of Florence; F. Falcini, MD, Department of BioMedicine, Section of Rheumatology, Transition Clinic, University of Florence.
authors.forename: Marco
authors.initials: M
authors.lastname: Matucci-Cerinic
authors.affiliation: From the Health Sciences Department, University of Florence, Anna Meyer Children's University Hospital, Florence; Department of BioMedicine, Section of Rheumatology, Transition Clinic, University of Florence, Florence; and Department of Internal Medicine, Endocrinology Unit, University of Florence, Florence, Italy.S. Stagi, MD, Health Sciences Department, University of Florence, Anna Meyer Children's University Hospital; F. Bertini, MD, Department of BioMedicine, Section of Rheumatology, Transition Clinic, University of Florence; L. Cavalli, MD, Department of Internal Medicine, Endocrinology Unit, University of Florence; M. Matucci-Cerinic, MD, Department of BioMedicine, Section of Rheumatology, Transition Clinic, University of Florence; M.L. Brandi, MD, Department of Internal Medicine, Endocrinology Unit, University of Florence; F. Falcini, MD, Department of BioMedicine, Section of Rheumatology, Transition Clinic, University of Florence.
authors.forename: Maria L
authors.initials: ML
authors.lastname: Brandi
authors.affiliation: From the Health Sciences Department, University of Florence, Anna Meyer Children's University Hospital, Florence; Department of BioMedicine, Section of Rheumatology, Transition Clinic, University of Florence, Florence; and Department of Internal Medicine, Endocrinology Unit, University of Florence, Florence, Italy.S. Stagi, MD, Health Sciences Department, University of Florence, Anna Meyer Children's University Hospital; F. Bertini, MD, Department of BioMedicine, Section of Rheumatology, Transition Clinic, University of Florence; L. Cavalli, MD, Department of Internal Medicine, Endocrinology Unit, University of Florence; M. Matucci-Cerinic, MD, Department of BioMedicine, Section of Rheumatology, Transition Clinic, University of Florence; M.L. Brandi, MD, Department of Internal Medicine, Endocrinology Unit, University of Florence; F. Falcini, MD, Department of BioMedicine, Section of Rheumatology, Transition Clinic, University of Florence. falcini@unifi.it.
authors.forename: Fernanda
authors.initials: F
authors.lastname: Falcini
mesh_terms: D000293:Adolescent; D001171:Arthritis, Juvenile / Q000097:blood* / Q000150:complications / Q000000981:diagnostic imaging; D015519:Bone Density / Q000502:physiology; D002648:Child; D005260:Female; D006801:Humans; D008297:Male; D010281:Parathyroid Hormone / Q000097:blood; D011859:Radiography; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000097:blood; D014808:Vitamin D Deficiency / Q000097:blood* / Q000150:complications / Q000000981:diagnostic imaging; D055815:Young Adult
chemical_list: D010281:Parathyroid Hormone; D014807:Vitamin D; C104450:25-hydroxyvitamin D
keywords: 25 OH VITAMIN D; BONE MINERAL DENSITY; JUVENILE IDIOPATHIC ARTHRITIS; OSTEOPOROSIS; PARATHYROID HORMONE