Incidence of vitamin D deficiency rickets among Australian children: an Australian Paediatric Surveillance Unit study

Med J Aust. 2012 Apr 16;196(7):466-8. doi: 10.5694/mja11.10662.

Abstract

Objective: To determine the incidence of and factors associated with vitamin D deficiency rickets in Australian children.

Design: 18-month questionnaire-based prospective observational study, using Australian Paediatric Surveillance Unit (APSU) data.

Setting: Australian paediatricians and child health workers, January 2006 - July 2007.

Participants: Children aged ≤ 15 years with vitamin D deficiency rickets (25-hydroxyvitamin D [25OHD] ≤ 50 nmol/L, and elevated alkaline phosphatase levels [> 229 IU/L] and/or radiological rickets).

Main outcome measures: Incidence of vitamin D deficiency rickets. Description of demographics, clinical presentation, identification and further analysis of overrepresented groups, and treatment regimens compared with best-practice guidelines.

Results: We identified 398 children with vitamin D deficiency (55% male; median age, 6.3 years [range, 0.2-15 years]). The overall incidence in children ≤ 15 years of age in Australia was 4.9/100 000/year. All had a low 25OHD level (median, 28 nmol/L [range, 5-50 nmol]) and an elevated alkaline phosphatase level (median, 407 IU/L [range, 229-5443 IU/L]), and 48 (12%) were hypocalcaemic. Ninety-five children had wrist x-rays, of whom 67 (71%) had rachitic changes. Most (98%) had dark or intermediate skin colour and 18% of girls were partially or completely veiled. Most children were born in Africa (252; 63%) and 75% of children were refugees. Duration of exclusive breastfeeding was inversely related to serum vitamin D levels in children < 3 years of age. Empirical vitamin D treatment was given to 4% of children before diagnosis.

Conclusions: Vitamin D deficiency rickets is a significant problem in Australia among known high-risk groups. Public health campaigns to prevent, identify and tre@vitamin D deficiency, especially in high-risk groups, are essential.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Africa / ethnology
  • Alkaline Phosphatase / blood
  • Australia / epidemiology
  • Child
  • Child, Preschool
  • Female
  • Humans
  • Incidence
  • Infant
  • Male
  • Refugees
  • Rickets / diagnosis
  • Rickets / epidemiology*
  • Rickets / etiology
  • Vitamin D / analogs & derivatives
  • Vitamin D / blood
  • Vitamin D Deficiency / diagnosis
  • Vitamin D Deficiency / epidemiology*

Substances

  • Vitamin D
  • 25-hydroxyvitamin D
  • Alkaline Phosphatase