Objective:

To evaluate the proportion of children and young people (CYP) tested in the emergency department who had either normal, insufficient or deficient serum levels of vitamin D.

Approach:

• Study Design: Single-centre, retrospective cohort study.
• Setting: Children’s ED serving a superdiverse, urban population with high levels of deprivation.
• Participants: All CYP aged <16 years who attended the Birmingham Children’s Hospital ED and had a serum vitamin D level sent between 1 January 2021 and 31 March 2022.
• Outcome Measures: Primary outcome: rates of vitamin D deficiency (<25 nmol/L) and insufficiency (25–49 nmol/L). Secondary outcomes: associated laboratory biomarkers and patient characteristics.

Key Findings:

• Out of 239 CYP tested, 36.8% had vitamin D insufficiency and 25.9% were deficient.
• Asian British patients had higher adjusted odds of deficiency compared to White patients (OR 2.81, 95% CI 1.11–7.85, p=0.037).
• Increasing Index of Multiple Deprivation (IMD) quintile was associated with lower odds of both deficiency and insufficiency.

Interpretation:

High levels of vitamin D deficiency and insufficiency were found in CYP tested in an emergency department serving a diverse population.

Limitations:

• The study is limited to a single centre and may not be generalizable to other populations.
• Retrospective design may limit the ability to establish causation.

Conclusion:

The findings highlight a diagnostic gap for populations at risk for vitamin D deficiency.