Bone Mineral Density in Females after Jejunoileal Bypass: A 25-year Follow-up Study

Background: Jejunoileal (JI) bypass was a widely performed operation for morbid obesity in the 1970s.The aim of this study was to investigate the long-term status of bone mineral density (BMD) after weight loss induced by this technique. Subjects and Methods: 18 female patients (age 48-79 y, BMI 23-43 kg/m2) had BMD measurements performed 25 years after JI bypass. Dual energy x-ray absorptiometry was used, and measured sites were the lumbar spine L2-L4, left femoral neck and total hip. Vitamin and mineral supplementation had not routinely been prescribed. An assessment was made on age-adjusted BMD values, and as to whether present BMD was related to present demographic and biochemical variables. Results: No significant reduction of BMD was found beyond that which was expected for age. BMD was inversely and separately related to age and body weight. The serum level of vitamin D was low in 45% of the patients, and inversely correlated to body weight and BMI. Alk phosphatase and parathyroid hormone were the best markers for low BMD. Conclusion: These results suggest that JI bypass has not been detrimental to bone density in females. We recommend, however, vitamin D and calcium supplements after malabsorptive procedures for morbid obesity.