Hyperhomocysteinaemia is associated with osteoporosis in patients with Crohn's disease

A high prevalence of osteoporosis is observed in Crohn's disease. Recent data have shown that homocysteinaemia is an important risk factor in low-bone mineralization and fracture.

To look for an association between homocysteinaemia and low-bone mineralization in Crohn's disease patients.

Ninety-two consecutive patients (sex ratio M/F 0.87; mean age: 36.6 +/- 13.2 years) were recruited between 2003 and 2005. Bone densitometry was performed on inclusion. The following parameters were analysed: age, sex, Crohn's Disease Activity Index, duration and extent of Crohn's disease, smoking status, corticosteroid treatment, immunosuppressive drugs, plasma homocysteine, folate and vitamin B12 concentration.

The prevalence of a high homocysteine level (>15 micromol/L) was 60%. Osteoporosis and low-bone mineralization observed in 26 (28%), and 60 (65%) patients, respectively. On a multivariate analysis, associated factors for osteoporosis and low-bone mineralization were respectively: hyperhomocysteinaemia (OR: 61.4; CI: 95: 23-250; P < 0.001), and ileal Crohn's disease [OR: 13.8; CI: 95: 2.5-150; P = 0.036] for osteoporosis and hyperhomocysteinaemia [OR: 63.7; CI: 95: 8.5-250; P < 0.001] and disease duration of at least 5 years [OR: 11.4; CI: 95: 1.31-99; P = 0.039] for low-bone mineralization. Results were similar whichever site osteoporosis was detected.

Hyperhomocysteinaemia was observed in 60% of our Crohn's disease patients and was strongly associated with low-bone mineralization and osteoporosis (OR: 61.4).