McNally has lead two observational studies to look at vitamin D status in
critical illness. The first study measured
vitamin D levels in 326 children in 6 PICUs across Canada and found that 70% of
children had vitamin D levels that were too low. Low vitamin D levels were
associated with worse clinical outcomes. The second, a
prospective longitudinal study, looked at vitamin D levels in children after
heart surgery. This study showed that 85% of children have vitamin D levels
that are too low following heart surgery. Vitamin D levels right after surgery were associated with a greater need
for cardiovascular support.
Systematic reviews of published pediatric trialsTo identify
the best vitamin D doses to use in clinical trials in PICU, we identified all
clinical trials (n>150) of high-dose vitamin D in children as part of a
systematic review. These trials were used to evaluate how different dosing
regimens affect vitamin D status, and confirmed that approved daily high-dose
regimens require more than a month to bring low vitamin D levels back to normal.
This review also showed that it was possible to normalize levels over a 48 to
72 hour period with a single loading dose of vitamin D (> 40000 IU), and
that a dose based on weight would help prevent both under and over dosing.
Pilot Clinical Trial in Congenital Heart Disease
designed a pilot clinical trial of vitamin D supplementation to determine
whether pre-operative daily vitamin D supplementation, at Health Canada
approved daily upper tolerable intake level, can safely prevent low vitamin D
levels in children following heart surgery. Enrollment was completed in 2015.
Pilot Randomized Controlled Trial of High Dose Vitamin D in Critically Ill Children
Dr. McNally designed a pilot dose evaluation clinical trial of high dose vitamin D supplementation to determine if high-dose vitamin D can safely and rapidly restore vitamin D levels in critically ill children within 7 days.. Enrollment was completed in November 2017.
Dr. McNally and his team recently completed a systematic review and meta-analysis of observations studies in the pediatric intensive care unit. They found that approximately 50% of critically ill children have vitamin D deficiency at the time of PICU admission. They also found that vitamin D deficiency was associated with more severe illness, multiple organ dysfunction, and mortality in the PICU setting.
Systematic review of pediatric observational studies