Prevalence and Predictors of Reduced Bone Density in Child and Adolescent Patients With Crohn's Disease

: Reduced bone mineral density (BMD) has broadly been found to be associated with inflammatory bowel disease across a number of geographical locations and cultures. We aimed to estimate the prevalence of reduced BMD and identify clinical predictors in a cohort of Crohn's disease patients (CD) in Saudi Arabia. We conducted a retrospective study involving children and adolescents with CD between 2013 and 2018. BMD was evaluated using dual-energy X-ray absorptiometry scans of the spine and body. A multivariate analysis was performed for the detection of predictors of low BMD. Sixty-four patients were enrolled. The median age was 16 years (range, 8-19 years) and 55% of patients were males. Total body BMD scanning identified 25 patients (39%) with osteoporosis. Twenty patients (31.3%) were found to have z scores consistent with osteopenia. A multivariate regression analysis identified a low weight-for-age z score (B coefficient = 0.347, 95% confidence interval [CI] = 0.211-0.482, p < 0.001 for Spine BMD and B coefficient = 0.321, 95% CI = 0.170-0.472, p < 0.001 for total body BMD), a low height-for-age z score (B coefficient = 0.187, 95% CI = 0.035-0.338, p = 0.017 for spine BMD and B coefficient = 0.0.258, 95% CI = 0.089-0.427, p = 0.004 for total body BMD), a low 25-hyroxyvitamin D level (B coefficient = 0.026, 95% CI = 0.013-0.038, p < 0.001 for spine BMD and B coefficient = 0.016, 95% CI = 0.002-0.031, p = 0.026 for total body BMD), and a higher number of corticosteroid induction courses (B coefficient = -0.567, 95% CI = -0.923 to -0.212, p = 0.003 for spine BMD and B coefficient = -0.566, 95% CI = 0.963-0.169, p = 0.007 for total body BMD) as predictors of low BMD. In the spine BMD analysis, older age at the time of presentation was identified as a significant predictor for low bone density (B coefficient = 0.254, 95% CI = 0.141-0.368, p < 0.001). In conclusion, Saudi Arabian children and adolescents with CD have a high prevalence rate of low bone density compared to Western populations. Several clinical characteristics are identified as significant predictors for low BMD.