Fracture risk increases with bariatric surgery
People with severe obesity who undergo bariatric surgery have a higher risk for fracture both before and after the procedure compared with controls with and without obesity, study data show.
“Obesity may not be as protective against fracture as was originally thought, Claudia Gagnon, PhD, FRCPC, of the endocrinology and nephrology unit at CHU de Québec Research Center in Québec City, told Endocrine Today. “This is supported by results from our study and recent evidence from the literature. Physicians should assess fracture risk in this population and address potentially modifiable risk factors (eg, vitamin D deficiency which is highly prevalent in this population). Decreased bone quality appears to have a predominant role over bone quantity in reducing bone strength in obesity.”
Gagnon and colleagues evaluated health care administrative databases to identify 12,676 patients who underwent bariatric surgery between 2001 and 2014 as well as age- and sex-matched controls with obesity (n = 38,028) and controls without obesity (n = 126,760) to determine whether bariatric surgery increases the risk for fracture.
At least one fracture was present in 10.5% of the bariatric surgery group, 8.1% of the obesity group and 6.6% of controls without obesity before surgery. Compared with controls without obesity, the risk for fracture was significantly higher in the bariatric surgery group (RR = 1.3; 95% CI, 1.21-1.39) and controls with obesity (RR = 1.18; 95% CI, 1.13-1.23) after adjustment for comorbidities, fracture history, socioeconomic deprivation and area of residence.
The bariatric surgery group was more likely to have sustained at least one fracture (4.1%) after a mean follow-up of 4.4 years compared with 2.7% of controls with obesity and 2.4% of controls without obesity. The bariatric surgery group had a significantly higher postoperative adjusted fracture risk compared with controls without obesity (RR = 1.44; 95% CI, 1.29-1.59) and controls with obesity (RR = 1.38; 95% CI, 1.23-1.55).
Compared with controls without obesity, the bariatric surgery group and controls with obesity had a higher risk for distal lower limb fracture and a lower risk for upper limb fracture. Compared with controls without obesity, the bariatric surgery group had higher risks for upper limb (RR = 1.65; 95% CI, 1.42-1.91), clinical spine (RR = 1.7; 95% CI, 1.06-2.73) and pelvic, hip and femur fractures (RR = 1.88; 95% CI, 1.37-2.58).
“Fracture risk assessment should be part of postoperative bariatric care,” Gagnon told Endocrine Today. “To minimize the effect of bariatric surgery on bone, guidelines should be followed and the importance of adherence to supplements and physical activity should be reinforced among patients and health care professionals. A referral to a bone specialist should be considered in cases in which fracture risk is high before surgery or when the biochemical parameters do not normalize of a fracture occurs after surgery. Finally, it is important to weight the benefits and risks of surgery for a given patient in order to propose the type if surgery that is best suited to the patient, as the efficacy of bariatric surgeries differs in terms of resolution and comorbidities associated with obesity.”
In an accompanying editorial, Marco Bueter, MD, PhD, attending surgeon and head of the bariatric program at University Hospital Zurich in Switzerland, wrote that the study “contribute[s] to an important research area, exploring the long term effects of bariatric surgery.”
“On the basis of the data presented by Rousseau and colleagues, as a bariatric surgeon I will certainly consider including assessment of fracture risk in the interdisciplinary algorithm of post-bariatric care for all my patients in the future,” he wrote. – by Amber Cox
For more information:
Claudia Gagnon, PhD, FRCPC, can be reached at Claudia.email@example.com.
Disclosure: Gagnon reports financial ties with Amgen and Eli Lilly. Bueter reports no relevant financial disclosures. Please see the full study for a list of all other authors’ relevant financial disclosures.