the Effect of Vitamin D in Crohn's Disease

the Effect of Target-oriented Vitamin D Treatment in Refractory Crohn's Disease

To evaluate the efficacy and safety of 12-week goal-directed therapy in the treatment of refractory inflammatory patients, and to initially explore treatment options. Patients with potential risk factors for recurrence after surgery for Crohn's disease and a serum 25(OH)D concentration <75 nmol/L were prescribed oral liquid vitamin D supplementation over 12 weeks using a specific protocol with dose adjusted 4-weekly to aim for a target level of 100-125 nmol/L.

The patients received oral liquid cholecalciferol supplementation (OsteVit DTM, Key Pharmaceuticals, Macquarie Park, NSW, Australia), supplied in 50 mL bottles (5000 units in 1 mL). A target 25(OH)D of 100-125 nmol/L was planned and the dose titrated 4-weekly.

Patients were evaluated at week 0 (screening visit), then 2- weekly until week 12, and at a follow-up visit at week 16. Key study endpoints were change in total 25(OH)D and attainment of level of 100e125 nmol/L. Intestinal inflammation was assessed via clinical disease activity (CDAI), faecal calprotectin (Calprotectin ELISA, Buhlmann, Basel, Switzerland), and circulating inflammatory markers (platelet count, serum albumin and C- reactive protein). Safety was assessed by direct questioning and 24- h urinary calcium excretion . Compliance was checked by dosing diaries completed by patients and measuring remaining cholecalciferol in bottles of the study drug.

Statistical analyses were performed using SPSS v20 (IBM Corporation, 2011) and GraphPad Prism v5.04 (Graphpad software, 2010). Dependent and independent samples t-tests, analysis of variance (ANOVA) and KruskaleWallis tests were used where appropriate. Associations with rise in 25(OH)D were examined by bivariate correlations. A p-value of 0.05 was considered statistically significant.

Inclusion Criteria:

1. Clinical diagnosis of Crohn's Disease

2. Must be able to swallow tablets

3. Have certain factors increase the risk of surgery in CD. include:

   • current smoking
   • fistulizing and stricturing disease behaviour
   • early steroid use (medical need for steroids for treatment of first flare)
   • disease in the end of the small bowel (i.e. ileum)
   • disease in the middle part of the small bowel (i.e. jejunum), and
   • young age at the time of the diagnosis.

Exclusion Criteria:

1. Other serious gastrointestinal diseases
2. pregnancy
3. hypercalcemia
4. hyperparathyroidism
5. chronic kidney disease and cardiovascular disease