Endocrine Abstracts

Physiology shows vitamin D has a role in the immune system and glucose metabolism. Experimental and epidemiological studies demonstrate associations between type 1 diabetes mellitus (T1DM) and vitamin D levels. Vitamin D deficiency appears undesirable in T1DM, although its significance in aetiology and progression is controversial.

We reviewed the outcome of implementing vitamin D screening at T1DM diagnosis. Methods were review of diabetes register, hospital case notes and pathology systems. Of the 46 T1DM cases diagnosed March 2011–2012, 42 were tested (seven sampling errors: six insufficient, one wrong tube). Within 1 month of diagnosis, three were re-sampled and a further child also tested, giving 39 evaluable vitamin D results (85% cases). Only 26% (10/39) had optimal levels (>75 nmol/l), 46% (18/39) suboptimal (50–75 nmol/l), 18% (7/39) insufficient (25–50 nmol/l) and 10% (4/39) were deficient (<25 nmol/l). Vitamin D levels showed no correlation with age, HbA1c or pH. There was a seasonal trend in vitamin D levels, with all four vitamin D deficiency cases diagnosed December–March (2/4 were non-Caucasian). 91% of hospital notes reviewed contained documented results. All four cases of deficiency had a treatment plan, although two had unclear documentation of implementation. Local practice guidelines have achieved increased identification and treatment of vitamin D deficiency.

Vitamin D deficiency is problematic in the UK. Ideally more children would receive preventative Vitamin D supplements if national recommendations are followed (all children under 5 years old, particularly children with other risk factors for vitamin D deficiency). The prevalence in our newly diagnosed T1DM population may simply reflect that of the wider community. Screening Vitamin D status at T1DM diagnosis provides an opportunity to address Vitamin D deficiency (<25 nmol/l) in this subgroup. Screening and treating Vitamin D at diagnosis can be advocated for the broader non-diabetes health benefits, although the potential effect on ameliorating T1DM progression requires further evaluation.