Bone mineral density, growth, pubertal development and other parameters in Brazilian children and young adults with sickle cell anaemia

Trop Med Int Health. 2013 Dec;18(12):1539-46. doi: 10.1111/tmi.12211. Epub 2013 Oct 18.

Abstract

Objectives: To evaluate the occurrence of low bone mineral density (BMD) and its relationship with clinical and laboratorial characteristics in children and young adults with sickle cell anaemia living in Northeast-Brazil, and to assess the role of radiography in diagnosing low BMD.

Methods: Bone mineral density of lumbar spine was measured by dual energy X-ray absorptiometry (DXA) in 27 patients with Sickle cell anaemia (SCA) aged 7-28 years. Clinical history, calcium and calorie intake, laboratory measurements, anthropometrics and pubertal development were assessed, and X-rays were obtained. Z-scores and T-scores for weight, height, Body Mass Index (BMI) and BMD were calculated using age and gender matched reference data.

Results: Mean lumbar spine BMD Z-scores and T-scores were -1.81 SD in boys and -0.80 SD in girls. BMD Z-scores were below -2 SD in 33.3% of girls and in 46.7% of boys. Low BMD (<-2 SD) occurred significantly more in patients with low height-for-age (P = 0.02), low weight-for-age (P = 0.001) and low BMI-for-age (P = 0.006). No significant relationships were found between BMD and other clinical and laboratory parameters. Radiography had a sensitivity of 75% and a specificity of 36% to detect low BMD, and was considered not useful in this context.

Conclusions: Patients with low height and/or low weight-for-age seem to be at high risk for developing low BMD.

Keywords: Brazil; Paediatrics; Sickle cell anaemia; bone mineral density.

MeSH terms

  • Adolescent
  • Adult
  • Anemia, Sickle Cell / complications
  • Anemia, Sickle Cell / pathology
  • Anemia, Sickle Cell / physiopathology*
  • Body Height
  • Body Mass Index
  • Body Weight
  • Bone Density*
  • Brazil
  • Child
  • Female
  • Growth Disorders / etiology*
  • Growth Disorders / pathology
  • Growth Disorders / physiopathology
  • Humans
  • Lumbar Vertebrae / pathology
  • Male
  • Puberty*
  • Young Adult