It has previously been noted that there is a high prevalence of osteoporosis in Crohn's disease, but there is little data about fractures.
Therefore, in a large European/Israeli study, doctors have examined the relationship between low bone mineral density and the prevalence of vertebral fractures in 271 patients with ileo-cecal Crohn's disease.
A total of 181 currently steroid-free patients with active Crohn's disease (98 completely steroid-naïve) and 90 steroid-dependent patients with inactive or quiescent Crohn's disease were recruited into the study.
All patients were investigated by dual X-ray absorptiometry scan of the lumbar spine and standardized lateral X-ray of the thoracic and lumbar spine.
In addition, an assessment of potential risk factors for osteoporosis was carried out for each subject.
Following such investigations, 39 asymptomatic fractures were seen in 25 of 179 (14.0%) steroid-free patients.
|Bone mineral density - no negative correlation with previous bowel resection |
|Alimentary Pharmacology and Therapeutics |
These 39 fractures comprised 27 wedge fractures and 12 concave fractures.
In the steroid-dependent subjects 14.6% were found to have fractures, with 17 fractures (14 wedge, 3 concavity) identified in 13 of 89 such patients.
The prevalence of fractures in steroid-naïve patients was 12.4%.
The research group found the average bone mineral density, expressed as a T score, of patients with fractures did not differ significantly from that of subjects free of fractures. In fact, over half of all patients (55%) with fractures had normal T scores.
Bone mineral density did correlate negatively with lifetime steroids, but not with previous bowel resection or current disease activity.
However, in women, but not in men, there was a positive relationship between fracture rate and age.
Professor R. W. Stockbrügger, the corresponding author of the report, said that the lack of correlation between the prevalence of bone fractures on the one hand, and the bone mineral density and lifetime steroid dose on the other, necessitates new hypotheses for the pathogenesis of the former.