A recent small pilot study has shown promise for the benefit of vitamin D in the treatment of inflammatory bowel disease (IBD) in both active ulcerative colitis (UC) and Crohn's disease (CD).
Ten patients were recruited, five of each suffering from UC and CD with mild-to-moderately active disease as evidenced by faecal calprotectin levels > 100μg/g. The participant's vitamin D (25(OH)D) level was initially less than 75nmol/L.
When given vitamin D over a 12 week period to raise their levels between 100-125nmol/L, the patients' reported decreased disease activity scores. The mean total dose of vitamin D for the 12 week study period was 492,000IU, with doses being titrated down as their vitamin D levels improved. Vitamin D supplementation was ceased if patients' vitamin D level exceeded 125nmol/L.
The study further reported that no effect was seen on faecal calprotectin levels, nor for other measures of inflammation, but that this may be attributable to the mildness of their condition. Though one patient needed to drop out of the study in week 4 due to viral illness, no serious adverse events such as hypercalcaemia or hyperphosphataemia were reported. One patient did however, develop hypercalcuria. No treatment for worsening IBD was required.
The authors concluded:
Short-term effect of this regimen on disease activity showed improved symptom-based activity scores, but had no impact on objective measures of intestinal or systemic inﬂammation. Whether this represents a placebo response or was of insufﬁcient duration to signiﬁcantly change inﬂammatory indices now requires an adequately powered randomised placebo-controlled trial.
- While this is only a pilot trial, there is great need for further study in the role of vitamin D in IBD, since other researchers have demonstrated benefits in other inflammatory diseases.
- IBD patients are at increased risk of malabsorption-induced vitamin D deficiency which has deleterious effects on bones, and may potentially worsen their disease progression.
- Follow-up vitamin D, serum calcium, serum phosphate and parathyroid hormone (PTH) levels after 3 months is prudent to track supplementation success and ward against adverse effects.
- IBD patients are an approved group for screening of vitamin D levels and this same research group has demonstrated significant deficiency among this population. Vitamin D was restricted from use as a screening tool in Australia from November 2014 because of hugely unnecessary costs to the healthcare system.
Garg M, Barr A, Rosella O, et al. A specified oral vitamin D supplementation regimen is effective for increasing serum 25(OH) vitamin D and is associated with a reduction in disease activity scores. J Gastroenterol Hepatol 2015;30(3):126.