Prevalence of low bone mineral density in inflammatory bowel disease and factors associated with it

Abstract

Background: Patients with inflammatory bowel disease (IBD) have numerous risk factors for low bone mineral density (BMD). We aimed to study the prevalence of low BMD in IBD and the factors associated with it.

Methods: BMD was measured by radial quantitative ultrasound, and clinical and biochemical characteristics were compared in prospectively enrolled patients and healthy age and gender-matched controls. Chi-square test, t test for independent samples, analysis of variance (ANOVA), Mann-Whitney U test and Kruskal-Wallis H tests were used as appropriate for univariate analysis to compare the characteristics between patients with and without abnormal BMD. Binary logistic regression analysis was done to determine the factors associated with low BMD in IBD patients.

Results: One hundred and six patients (Crohn's disease [CD] = 35, ulcerative colitis [UC] = 71) and 55 controls were included. Low BMD was equally prevalent in CD, UC and controls (42.9%, 36.6%, 36.4% respectively, p = 0.791). Serum calcium and vitamin D were significantly lower in IBD patients compared to controls (p < 0.001 and p = 0.003, respectively) but not between patients with low and normal BMD. Older age (Odds ratio [OR] = 66.12 [9.299-470.243], p < 0.001), late onset of disease (OR = 4.795 [1.067-21.543], p = 0.041) and absence of steroid usage (OR = 0.272 [0.089-0.832], p = 0.022) were significantly associated with low BMD.

Conclusions: The prevalence of low BMD in patients with IBD was similar to controls and this was associated with increasing age, late onset of disease, and absence of steroid usage. Judicious use of steroids can help preserve bone health in IBD.

Keywords: Bone densitometry; Bone health; Bone mineral density; Corticosteroid; Crohn’s disease; Dual-energy X-ray absorptiometry; Inflammatory bowel disease; Quantitative ultrasound; Radial quantitative ultrasound; Ulcerative colitis; Vitamin D.