The frequency of vitamin D deficiency in adults with Crohn's disease
JS Siffledeen | K Siminoski | H Steinhart | G Greenberg | et al
Vitamin D deficiency is a putative, pathogenic cofactor
in the increase in osteopenia and osteoporosis seen
in patients with Crohn's disease.
To determine the frequency of low serum 25-hydroxy-vitamin
D3 (25-OHD) levels and the associated alterations
in bone mineral density in a cohort of adults with Crohn's
25-OHD levels were determined in 242 consecutive patients
with Crohn's disease seen in two tertiary inflammatory
bowel disease referral centres. Bone mineral density
was assessed by dual energy x-ray absorptiometry.
Nineteen (8%) patients exhibited vitamin D deficiency
(25-OHD less than 25 nmol/L) and 52 (22%) patients exhibited
vitamin D insufficiency (25-OHD less than 40 nmol/L).
Mean T-scores at the lumbar spine, femoral neck, total
hip and ultradistal radius in the group with low 25-OHD
did not differ from those of the normal
25-OHD group. Serum alkaline phosphatase and parathyroid
hormone levels were higher in the low 25-OHD group than
in the normal group. Decreased red blood cell (RBC)
folate predicted low 25-OHD in male patients, while
smoking, RBC folate and serum iron predicted low 25-OHD
in female patients. The rate of low 25-OHD deficiency
in the winter was significantly higher than that in
the summer (11.9% versus 2.8%, respectively).
Vitamin D-deficient Crohn's disease patients exhibit
biochemical evidence of metabolic bone disease, without
detectable differences in bone mineral density. Sunlight
exposure, nutrition and smoking status were predictors
of vitamin D deficiency in this patient cohort.