Risk of fractures following bariatric surgery with Roux-en-Y gastric bypass or sleeve gastrectomy: a Danish population-based cohort study.

Objective: We examined the association between Roux-en-Y gastric bypass (RYGB) or sleeve gastrectomy (SG) and fracture risk, including major osteoporotic fractures (MOF), and the use of anti-osteoporosis medication (AOM). While RYGB is associated with impaired bone health and increased fracture risk, it remains uncertain whether SG has a similar impact and whether this risk is primarily due to MOF or any fracture.

Design: We conducted a nationwide cohort study covering patients treated with RYGB (n = 16 121, 10.2-year follow-up) or SG (n = 1509, 3.7-year follow-up), from 2006 to 2018, comparing them with an age- and sex-matched cohort (n = 407 580).

Methods: We computed incidence rates and adjusted hazard ratios (HRs) with 95% CIs, using Cox regression for any fracture, MOF, and use of AOM with adjustment for comorbidities.

Results: Compared with the general population cohort, RYGB was associated with an increased risk of any fracture (HR 1.56 [95% CI, 1.48-1.64]) and MOF (HR 1.49 [1.35-1.64]). Sleeve gastrectomy was associated with an increased risk of any fracture (HR 1.38 [1.13-1.68]), while the HR of MOF was 1.43 (0.97-2.12). The use of AOM was low but similar in all cohorts (approximately 1%).

Conclusions: Bariatric surgery increased the risk of any fracture and MOF to similar extend. Risks were similar for RYGB and SG. However, SG had a shorter follow-up than RYGB, and the cohort size was rather small. More research is needed for long-term SG fracture risk assessment. The use of AOM was low in all cohorts.