ABSTRACT
Patients with inflammatory bowel disease [IBD] are at high risk for low bone mineral density [BMD]. This study aimed to evaluate BMD in IBD patients and its relationship with bone metabolism in a group of Iranian patients. A cross-sectional study was conducted on patients with IBD to assess BMD status and serum biochemical factors. After getting the demographic data from 200 patients, they were screened using dual-energy X-ray absorptiometry of the lumbar spine [L2-L4] and femoral neck for BMD status. Serum levels of calcium, phosphate, alkaline phosphatase [ALP], and 25-hydroxyvitamin D [25-OH vitamin D] were measured to assess the bone metabolism status. Two hundred patients with IBD were enrolled in the study. One hundred and eighty three [91.5%] patients were identified as having ulcerative colitis [UC] and 17 [8.5%] as having Crohn's disease [CD]. Based on the lumbar and femoral neck bone mass densitometry, 148 [74.4%] patients had low BMD at either lumbar spine or femoral neck. Of these, 100 patients [50.3%] were osteopenic and 48 patients [24.1%] were osteoporotic. A 58.6% and 61% of patients with UC had low BMD in the lumbar and femoral neck, respectively. These results for those with CD were 76.5% and 70.6%, respectively. The mean of femoral neck and lumbar T-scores in patients with UC were -1.14 and -1.38, and in patients with CD were -1.24 and -1.47, respectively [P > 0.05]. The mean [ +/- SD] levels for calcium [Ca] in UC and CD were in the normal range. The mean [ +/- SD] levels of ALP and 25-OH vitamin D in both the groups were in the normal range, and in comparison between groups [UC and CD], no significant differences were observed [P = 0.20 for ALP and P = 0.44 for 25-OH vitamin D]. In the assessment of correlation between biochemical markers and BMD, an inverse correlation between lumbar T-score and ALP or 25-OH vitamin D only in patients with UC was observed. The high prevalence of low BMD in the Iranian population with IBD needs attention. The subclinical vitamin D deficiency may contribute to bone loss in IBD patients, which is more pronounced in patients with UC in this study because of the small population of patients with CD