Bone health screening practices with dual-energy X-ray absorptiometry and prediction of abnormal results in pediatric inflammatory bowel disease

Abstract

Objectives: Pediatric patients diagnosed with inflammatory bowel disease (IBD) are at risk of suboptimal peak bone mass attainment. This study aimed to understand rates of bone health screening adherence, describe factors associated with dual-energy X-ray absorptiometry (DXA) acquisition, and identify factors associated with abnormal DXA.

Methods: We performed a retrospective cohort study of pediatric IBD patients over a 10-year time frame. We included IBD patients (2-20 years of age) enrolled in ImproveCareNow and excluded patients with primary metabolic bone disease. Time-to-event methods and multivariable logistic regression were employed to identify factors associated with DXA acquisition and abnormal DXA.

Results: In 676 patients, 464 (68.63%) pediatric patients with IBD had a risk factor for low bone mineral density (BMD); 137 (29.53%) underwent an initial DXA scan. Quiescent disease was significantly associated with a reduced likelihood of DXA (hazard ratio [HR]: 0.48; 95% confidence interval [CI]: 0.24-0.97), while weight z-score <-2 was significantly associated with DXA performance (HR: 2.07; 95% CI: 1.08-3.98). Abnormal DXA results (BMD z-score ≤-1) occurred in 59 (35.54%) individuals. After adjusting for visit diagnosis, delayed puberty, severe disease course, 6 months or greater of steroid exposure, and history of fracture, BMI z-score <-1 (odds ratio: 5.45; 95% CI: 2.41-12.33) was associated with abnormal DXA.

Conclusions: DXA screening occurred in less than one-third of eligible pediatric IBD patients. Compliance was more common in patients with a weight z-score <-2 and less common in those with quiescent disease. BMI strongly predicted abnormal DXA results when adjusting for risk factors for abnormal BMD.

Keywords: DXA; IBD; bone mineral density.