P312 Trabecular bone score in patients with inflammatory bowel diseases

Abstract

Introduction Osteoporosis and osteopenia are known chronic complications of inflammatory bowel diseases (IBD). It is known that areal bone mineral density (aBMD) does not sufficiently reflect bone strength and quality. The trabecular bone score (TBS) provides an indirect measurement of bone microarchitecture, independent of areal bone mineral density (aBMD). Aims and Methods The aim was to assess bone involvement in IBD patients with regard to disease behaviour using TBS in comparison with lumbar spine (LS) BMD. The cohort consisted of 84 IBD patients - 53 with Crohn's disease (CD) and 31 with ulcerative colitis (UC). Clinical characteristics of every patient were recorded, i.e. age, sex, anthropometry, clinical behaviour, location of disease according to the Montreal classification, medication. The BMD was determined by dual-energy X-ray absorptiometry (DXA, Hologic Discovery) at the lumbar spine. TBS was determined by TBS Insight® soft ware (Medimaps, France). Results The mean age of the cohort was 42 ± 14.2 years with the average disease duration of 11 ± 7 years. 12/84 (14 %) of the cohort were postmenopausal women. 39.6 % (21/53) of CD patients had prior resection of the ileum. At the time of assessment 8/84 (9.5 %) of the IBD patients (3 CD vs 5 UC patients) were on glucocorticoid therapy with > 5 mg equivalent to prednisolone daily. The percentage of patients with substitution of vitamin D3 (800 IU) and calcium (0.5- 1 g) was similar between CD and UC (24.5 % vs 29 %), none of the patients were on anti-porothic treatment. Biological treatment was common in the study population (48.4 % UC vs 50.9 % CD). The aver age LS BMD was 0.964 ± 0.113 g/cm2 and TBS 1.36 ± 0.14. The median serum 25(OH)D level was in the deficiency range in IBD patients (mean ± SD, 20.3 ± 8.2 ng/mL). There was a modest correlation between LS BMD and spine TBS (r = 0.42). Significantly lower TBS although not LS BMD was found in patients with fistulising CD as compared to those with luminal disease (p = 0.0039). We did not observe any difference in TBS or BMD in UC patients according to the disease behaviour. Conclusion We observed that spine TBS can identify quality of bone mineral density in patients with Crohn's disease better than BMD itself. CD patients with severe disease are at higher risk of low bone mineral density.