Vitamin D insufficiency among hospitalised children in the N orthern T erritory

Aim Acute lower respiratory infections ( ALRI s) are the most common reason for hospitalisation of young children in the N orthern T erritory of A ustralia. International studies have linked vitamin D deficiency with increased risk of ALRI in paediatric populations, but this has not been explored in tropical regions such as the Top End of the N orthern T erritory. The aim of this study is to determine the prevalence of vitamin D insufficiency among children hospitalised with ALRI in the N orthern T erritory. Methods Vitamin D serum metabolite (25 OHD 3) levels were retrospectively measured using liquid chromatography–mass spectrometry in 74 children (64% male; 57% I ndigenous) aged less than 3 years admitted to R oyal D arwin H ospital in the N orthern T erritory of A ustralia between M ay 2008 and M ay 2010. Results There were 44 (59%) ALRI ‐classified hospitalisations and 30 (41%) non‐ ALRI ‐classified hospitalisations. The most common ALRI diagnoses were bronchiolitis ( n = 22, 30%) and pneumonia ( n = 21, 28%), whereas the most common non‐ ALRI diagnosis was gastroenteritis ( n = 20, 27%). Overall, 24/74 (32%) children had 25 OHD 3 levels <75 nmol/L (insufficiency). For children hospitalised with ALRI , 23% (10/44) had vitamin D insufficiency compared with 47% (14/30) among children hospitalised for other reasons (odds ratio 0.34, 95% confidence interval 0.11–1.03; P = 0.043). Twelve of the 20 (60%) children hospitalised for gastroenteritis had vitamin D insufficiency. Conclusions Vitamin D insufficiency was observed in almost one‐third of these hospitalised children. Children hospitalised with an ALRI were less likely to have vitamin D insufficiency compared with children hospitalised for other conditions (predominantly gastroenteritis).