Loading...
 
Toggle Health Problems and D

Crohn’s disease associated with vitamin D and latitude – meta-analysis Dec 2015

Vitamin D status in relation to Crohn’s disease: meta-analysis of observational studies

Nutrition DOI: http://dx.doi.org/10.1016/j.nut.2015.11.008
Mehdi Sadeghian, Parvane Saneei, Fereydoun Siassi, Ahmad Esmaillzadeh

Study Highlights

  • Growing evidence suggests a relationship between vitamin D status and the progression of Crohn’s disease.
  • Vitamin D status in Crohn’s disease compared with healthy controls
    has inconsistent results in deficiency and correlations with disease activity.
  • Summarizing earlier evidence on the association of vitamin D status and Crohn’s disease,
    this meta-analysis revealed that CD patients had lower mean levels of 25(OH)D compared with healthy controls.
  • A significant correlation was seen between latitude and 25(OH)D levels.
    More than half of the patients with CD had vitamin D deficiency.
  • Individuals with lower concentrations of 25(OH)D had greater disease activity than those with sufficient concentrations.


Background and Aims
Inconsistent findings were published regarding vitamin D status among patients with Crohn’s Disease (CD) and the association with disease severity. We aimed to perform a meta-analysis evaluating serum 25-hydroxyvitamin D and 1,25dehydroxyvitamin D among CD patients compared with healthy and non-healthy controls and the prevalence of vitamin D deficiency as well as the association with disease activity.

Methods
We searched MEDLINE, SCOPUS, EMBASE and Google Scholar up to March 2015 for observational studies assessed serum vitamin D levels in CD patients. A total of 63 studies were included in the following four meta-analyses:

  • 1) a meta-analysis on the mean difference of 25(OH)D levels in CD patients compared with healthy (number of studies=27) and non-healthy (n=25) controls;
  • 2) a meta-analysis on the mean difference of 1,25(OH)2D3 levels in CD patients compared with healthy (n=7) and non-healthy (n=8) controls;
  • 3) a meta-analysis on the prevalence of vitamin D deficiency (n=34);
  • 4) a meta-analysis on the correlation coefficients between vitamin D status severity of CD (n=6).

Subgroup analysis and meta-regression were used to discover possible sources of between-study heterogeneity.

Results
It was found that CD patients had lower levels of 25(OH)D compared with healthy (-3.99 ng/mL; 95% Confidence Interval CI: -5.91 to -2.08) but not non-healthy controls (-1.07 ng/mL; 95% CI: -2.84 to 0.70). There was also no significant mean difference for 1,25(OH)2D3 for both healthy and non-healthy controls. Meta-analysis on the prevalence of vitamin D deficiency showed an overall prevalence of 57.7% (95% CI: 0.502 to 0.649). An inverse association was observed between serum vitamin D and severity of CD (-0.36; 95% CI: -0.48 to -0.24). Meta-regression showed that mean levels of 25(OH)D was decreased 0.09 for each unit change of latitude among CD patients compared with healthy controls (B=-0.09, P=0.004, I2residual=86.08%).

Conclusion
we found that patients with Crohn’s disease had lower serum 25(OH)D concentrations compared with their healthy counterparts and more than half of them have hypovitaminosis D. Moreover, there was an inverse correlation between circulating 25(OH)D concentrations and severity of Crohn’s disease.

Publisher wants $31 for the PDF