Bone mineral density in spanish children at the diagnosis of inflammatory bowel disease

The association between low bone mineral density (BMD) and inflammatory bowel disease (IBD) is already known. Our study, performed in Spanish pediatric IBD patients at diagnosis onset, shows that low BMD already existed at the beginning of the disease. Low weight and height are also associated with low BMD and have to be considered as risk factors.

Inflammatory bowel disease (IBD) has been reported to be associated, even at disease onset, with low bone mass. The aim of this study was to know the bone mineral density (BMD) status in the IBD pediatric population of group of Spanish children, at the time of diagnosis.

Retrospective review of patients' records from pediatric IBD patients diagnosed in our unit in the last 10 years. BMD was measured at the time of diagnosis and was expressed by Z-score.

Fifty-seven patients were included. Sixty-one percent were male and 47.4% had Crohn's disease (CD). Average age was 11.18 (SD 2.24) years old. Median BMD Z-score was - 0.30 (interquartile range: - 1.10 to + 0.10). Low BMD, defined as Z-score ≤  - 2SD, was present in 5% of patients, but there was no single patient with osteoporosis. There were no differences in BMD between Ulcerative Colitis (UC) and CD. Statistical differences appeared between healthy Spanish pediatric population and our IBD cohort, these having lower BMD for the same age and gender. A linear regression analysis showed a significant association between BMD Z-score and patient´s weight and height Z-score with a p values of 0.001 and 0.048, respectively.

Suboptimal bone density is present at diagnosis in Spanish pediatric patients with IBD. There is no difference in BMD between patients with CD and UC. Lower weight and height are associated with a lower BMD; thus these data at IBD diagnosis should be considered as a risk factor for bone disease in the pediatric population.