Bone Mineral Density and Bone Remodeling in Tunisian Patients with Inflammatory Bowel Disease

A high prevalence of osteopenia and osteoporosis is observed in patients with Inflammatory Bowel Disease (IBD).

The aim of our study was to investigate the prevalence of bone loss, bone remodeling and risk factors in Tunisian patient with IBD.

The study included 40 patients with IBD and 32 age- and sex-matched healthy controls subjects. All participants underwent bone densitometry by dual energy X-ray absorptiometry at the femoral neck and lumbar spine. Serum levels of 25-hydroxy vitamin D (25(OH)D), parathyroid hormone (PTH), osteocalcin(OC), and urinary degradation products of C-terminal telopeptide of type I collagen (CTXI) were measured in all participants to assess the bone metabolism status.

Twelve (30%) patients were normal, 32.5% were osteopenic and 37.5% were osteoporotic. Osteoporosis was more frequent in IBD patients than controls (p=0.0001). Age and inflammation were associated with low bone mineral density (BMD). Mean calcium, phosphorus and alkaline phosphatase levels were similar in both groups. Median 25(OH) D levels were significantly lower in IBD patients compared with controls (p=0.0001). Median urinary CTXI levels were significantly higher in IBD patients compared with healthy controls (p=0.007). No significant differences between IBD patients and controls concerning the median serum OC and PTH levels were found.

In our study, there is a high prevalence of low BMD in IBD patients and an increase in bone resorption without a change of bone formation. Low BMI and hypovitaminoses D were identified as risk factors for low BMD.