Metabolic bone disease and fracture risk after gastric bypass and sleeve gastrectomy: comparative analysis of a multi-institutional research network.

Background: Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy (SG) are the two most performed bariatric procedures. Multiple studies have investigated the metabolic bone complications after bariatric surgery, but there is a paucity of data comparing bone health after RYGB and SG.

Objectives: To compare the rates of major fractures and osteoporosis after Roux-en-Y gastric bypass and sleeve gastrectomy.

Setting: Data from TriNetX multi-institutional research network that includes data from multiple health care organizations in the USA was analyzed at West Virginia University.

Methods: We conducted a retrospective cohort study using TriNetX, a federated multi-institutional research network. We identified patients who underwent RYGB or SG. Primary outcome was the rate of major fractures at 3 years after the procedure. Other outcomes included the rate of spine fracture, femur fracture, osteoporosis, and vitamin D deficiency at follow-up.

Results: In unmatched analysis, patients with SG were less likely to have major fractures or an osteoporosis diagnosis than RYGB patients at 3 years after the procedure (P < .05). After propensity-score matching, similar results were noted; patients with SG were less likely to have major fractures than RYGB patients at 3 years after procedure (2.85% versus 3.66%, risk ratio [RR]: .78, 95% confidence interval [CI]: .71-.85), and a lower rate of osteoporosis diagnosis was noted in the SG group. High rates of vitamin D deficiency were noted in both cohorts. The incidence of spine fractures was significantly lower in the SG group than in the RYGB group (.76% versus 1.18%, RR: .65, 95% CI: .54-.77). Similarly, the incidence of femur fracture was significantly lower after SG (RR: .62, 95% CI: .44-.88). Female sex, higher age, smoking history, and diabetes were independently associated with osteoporosis diagnosis during follow-up (all P values <.05).

Conclusion: Our analyses showed that RYGB is associated with a higher risk of osteoporosis, vitamin D deficiency, and osteoporotic fractures. Thus, in patients with a higher baseline osteoporotic risk, SG may be preferred option; however, further studies are needed.