The effect of bariatric surgery on ischemic stroke risk.

Background: Metabolic and bariatric surgery (MBS) has demonstrated improvements in diabetes and cardiovascular health. The effect of MBS on the risk of ischemic stroke remains unclear.

Objectives: The goal of this study was to determine the risk of stroke following MBS compared with patients with obesity who qualified for but did not undergo MBS.

Setting: The Mariner Database, a national claims database.

Methods: We identified patients with body mass index (BMI) ≥40 or those with a BMI and a qualifying co-morbidity, who underwent MBS between 2010 to 2019. Similar patients who did not undergo MBS served as controls. Coarsened exact matching was performed followed by logistic regression analysis to determine the effect of BMS on stroke risk.

Results: A total of 70 622 BMS patients and 1 320 182 MBS-eligible controls were identified. After matching, the 1-year stroke risk among MBS patients (n = 56 514) versus controls (n = 56 514) was .6% versus 1.2% (OR .54, 95% CI .47-.61). The 5-year stroke risk for MBS (n = 27619) versus control (n = 27619) was 2.8% versus 3.6% (OR .78, 95% CI .65-.90).

Conclusion: MBS appears to reduce the risk of stroke following surgery. To our knowledge, this is the largest sample size in a study of ischemic cerebrovascular disease in bariatric surgery.