To Örebro University

BACKGROUND: Weight changes after Roux-en-Y gastric bypass (RYGB) follow different trajectories, but the effects of different trajectories on death and cardiovascular events are largely unknown. The aim of the current study was therefore to evaluate the effects of weight changes after RYGB on cardiovascular events and mortality rate.

METHODS: This cohort study included patients who underwent primary RYGB in Sweden from 2007 to 2018 with a complete registration of weight at baseline, at nadir weight loss and 5-year follow-up (n = 25 230) with a mean BMI of 42.1 ± 5.2 kg/m2, age 42.5 ± 11.2 years, and 19 420 (77%) women. Patients were stratified based on weight change from nadir weight loss. The main outcome measures were major cardiovascular event (MACE) or death.

RESULTS: Over a mean follow-up of 10.6 years, 1276 patients experienced at least one episode of a MACE, and 707 died. An increased risk for death and MACE was seen in patients with continued weight loss after nadir (adjusted HR compared to recurrent weight gain of 0-20% of weight lost at nadir among patients who initially lost 20-35% total weight (TWL): 1.80 (1.41-2.31) and 1.62 (1.35-1.94) respectively), and for patients who experienced >50% recurrent weight gain from nadir (adjusted HR compared to patients with recurrent weight gained 0-20% TWL: 1.61 (1.07-2.43) and 1.48 (1.09-2.00) respectively).

CONCLUSION: Continued weight loss and significant recurrent weight gain after the initial weight nadir were both associated with a higher risk for MACE and death after RYGB. These should be considered non-desirable weight trajectories requiring further clinical evaluation and increased support.