- A French study shows that bariatric surgery is associated with lowered colorectal cancer (CRC) risk consistent with the general population.
Why this matters
- Previous studies have shown mixed results, but they had fewer CRC cases and generally younger populations.
- Retrospective study based on French electronic health data of individuals with obesity (N=1,045,348; age, 50-75 years; 74,131 underwent bariatric surgery).
- Funding: None disclosed.
- During follow-up, the CRC rate was 1.2%, and 63,649 colorectal benign polyps were found.
- 0.6% of the surgical cohort developed CRC compared with 1.3% of the nonsurgery cohort (P<.001>
- In the nonsurgery cohort:
- 9417 cases were expected, but 12,629 were observed.
- Standardized incidence ratio, 1.34 (95% CI, 1.32-1.36).
- In the surgical cohort:
- 428 cases were expected based on the general French population, and 423 were observed.
- Standardized incidence ratio, 1.0 (95% CI, 0.90-1.09).
- Propensity-score matched analysis found reduced risk in surgical patients for:
- CRC: HR, 0.68 (95% CI, 0.60-0.77).
- Colorectal benign polyp: HR, 0.56 (95% CI, 0.53-0.59).
- Compared with adjust gastric banding, gastric bypass and sleeve gastrectomy were associated with lower incidence of:
- CRC: 0.5% for each vs 0.7% (P=.04).
- Colorectal benign polyps: 3.1% for each vs 5.0% (P<.001>
- Retrospective analysis.