Gastric Bypass

Patients, including those aged 65 years or older, who undergo Roux-en-Y gastric bypass (RYGB) for severe obesity should be followed long term for fractures, because they face a substantially increased risk compared with those who undergo adjustable gastric banding (AGB), say US investigators. Elaine W. Yu, MD, Endocrine Unit, Massachusetts General Hospital, Boston, and colleagues examined the Medicare claims data of more than 42,000 individuals who underwent bariatric surgeries during an 8-year period.

Risk for nonvertebral fractures

They found that after an average follow-up of 3.5 years; RYGB patients had a 73% increase risk for nonvertebral fractures in comparison with AGB patients. The risk for hip fractures was almost threefold higher among RYGB patients vs those in the AGB group. The risk for wrist fracture was 70% higher; so that for pelvis fracture was almost 50% greater.

The study, publish online in JAMA Surgery on May 15; so show that the increase risk could not be explain by age, sex, diabetes status, or race. The fracture risk patterns seen among individuals aged 65 years or older were similar to those of younger patients.

The team writes that, despite the “myriad health benefits” associate with bariatric surgery; so increase fracture risk is an important factor to discuss with patients seeking RYGB. In an accompanying editorial, Margaret E. Smith, MD, and Amir A. Ghaferi, MD, from the Department of Surgery, University of Michigan, Ann Arbor, commend the authors for conducting the study, although they note that it has several limitations.

They highlight the fact that although the fracture rate; so may be significantly different between RYGB and AGB patients, “the clinical effect of minimal absolute differences in fractures is likely insignificant.” For example, despite a hazard ratio of 2.81, only 103 patients who underwent RYGB (0.4%); so experience a hip fracture, compare with 25 (0.2%) of the gastric band cohort.

As bariatric surgery is often refer to as a ‘life-long’ treatment for obesity; so physicians focus on long-term outcomes and managing the longitudinal effects of this life saving treatment. In explaining the increase fracture risk following RYGB, the researchers say that the mechanism is “likely multifactorial” and may include skeletal unloading due to the weight loss and calcium malabsorption post surgery.

Studies have shown that vitamin D, calcium supplementation, and exercise can slow bariatric surgery-relate bone loss. The authors note that guidelines for health management recommend supplementation and that exercise and protein supplements may be beneficial. In theory, careful use of antiresorptive osteoporosis agents could inhibit high bone turnover associate with RYGB, but no trials have conduct to test the safety and efficacy of this therapeutic strategy,” they conclude.