title: [Low bone mineral density in juvenile idiopathic arthritis: Prevalence and related factors].
abstract: BACKGROUND
  Height adjustment is currently recommended for Z-score bone mineral density (BMD) assessed by dual energy X-ray absorptiometry. At present there are no studies that evaluate the prevalence of low BMD in paediatric patients with Juvenile Idiopathic Arthritis (JIA) in Spain following current recommendations.
  
  
  OBJECTIVE
  To evaluate low BMD in JIA in paediatric patients with JIA in Spain following the latest recommendations, as well as to assess associated factors.
  
  
  METHODS
  Observational cross-sectional study of Spanish JIA patients from 5 to 16 years-old, followed-up in a Paediatric Rheumatology Unit between July 2014 and July 2015. Anthropometric, clinical and treatment data were recorded. Dual energy X-ray absorptiometry, and bone metabolism parameters were collected, and a completed diet and exercise questionnaire was obtained.
  
  
  RESULTS
  A total of 92 children participated. The population prevalence estimation of low BMD was less than 5% (95% CI). A significant positive correlation was found in the multiple linear regression analysis between the body mass index percentile (B: 0.021; P<.001) and lean mass index (B: 0.0002; P=.012), and BMD Z-score adjusted for height (Z-SAH). A significant negative correlation was found between fat mass index (B: -0.0001; P=.018) and serum type I collagen N-propeptide (B: -0,0006; P=.036) and Z-SAH.
  
  
  CONCLUSIONS
  Low BMD prevalence in JIA patients in our population is low. An adequate nutritional status and the prevalence of lean over fat mass seem to promote the acquisition of bone mass. Those JIA patients with lower BMD could be subjected to an increase of bone turnover.
authors.affiliation: Sección de Reumatología Pediátrica, UGC Pediatría, Hospital Regional Universitario de Málaga, Málaga, España; Departamento de Pediatría y Farmacología, Facultad de Medicina, Universidad de Málaga, Málaga, España. Electronic address: rociogalin@hotmail.com.
authors.forename: Rocío
authors.initials: R
authors.lastname: Galindo Zavala
authors.affiliation: Sección de Reumatología Pediátrica, UGC Pediatría, Hospital Regional Universitario de Málaga, Málaga, España.
authors.forename: Esmeralda
authors.initials: E
authors.lastname: Núñez Cuadros
authors.affiliation: UGC Pediatría, Hospital Regional Universitario de Málaga, Málaga, España.
authors.forename: Laura
authors.initials: L
authors.lastname: Martín Pedraz
authors.affiliation: Sección de Reumatología Pediátrica, UGC Reumatología, Hospital Regional Universitario de Málaga, Málaga, España.
authors.forename: Gisela
authors.initials: G
authors.lastname: Díaz-Cordovés Rego
authors.affiliation: Sección de Gastroenterología y Nutrición Infantil, UGC Pediatría, Hospital Regional Universitario de Málaga, Málaga, España.
authors.forename: Carlos
authors.initials: C
authors.lastname: Sierra Salinas
authors.affiliation: UGC Pediatría, Hospital Regional Universitario de Málaga, Málaga, España.
authors.forename: Antonio
authors.initials: A
authors.lastname: Urda Cardona
mesh_terms: D000293:Adolescent; D001171:Arthritis, Juvenile / Q000150:complications* / Q000503:physiopathology; D015519:Bone Density; D002648:Child; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D010024:Osteoporosis / Q000150:complications* / Q000453:epidemiology* / Q000503:physiopathology; D015995:Prevalence
keywords: Artritis idiopática juvenil; Baja densidad mineral ósea para la edad cronológica; Body composition; Bone mineral density; Composición corporal; Densidad mineral ósea; Estado nutricional; Juvenile idiopathic arthritis; Low bone mineral density for chronological age; Marcadores del metabolismo óseo; Nutritional status; bone turnover markers