Adherence to a healthy lifestyle in relation to colorectal cancer incidence and all-cause mortality after endoscopic polypectomy: A prospective study in three U.S. cohorts

It remains unknown whether maintenance of a healthy lifestyle after endoscopic polypectomy could still confer benefit for colorectal cancer (CRC) incidence and mortality. In this study, we defined a healthy lifestyle score based on body mass index, smoking, physical activity, alcohol consumption and diet (range, 0-5). We used Cox proportional hazards regression to estimate the hazard ratios (HRs) for the associations of healthy lifestyle score and individual lifestyle factors with CRC incidence and all-cause mortality. During a median of 10 years of follow-up of 24 668 participants who underwent endoscopic polypectomy, we documented 161 CRC cases and 4857 all-cause deaths. A higher healthy lifestyle score after endoscopic polypectomy was associated with lower risk of CRC and all-cause mortality. Compared with individuals with 0 to 1 healthy lifestyle factors, those with 2, 3 and 4 to 5 healthy lifestyle factors had a HR for CRC risk of 0.86 (95% confidence interval [CI], 0.60-1.24), 0.73 (95% CI, 0.47-1.14) and 0.52 (95% CI, 0.27-1.01), respectively (Ptrend =.03). The corresponding HR (95% CI) for all-cause mortality was 0.83 (95% CI, 0.76-0.90), 0.63 (95% CI, 0.56-0.70) and 0.56 (95% CI, 0.48-0.65), respectively (Ptrend <.0001). In the joint analysis of pre- and postpolypectomy periods, patients with a healthy postpolypectomy lifestyle had a lower incidence of CRC regardless of their prepolypectomy exposure, whereas those with a healthy lifestyle in both periods had a lower mortality than those with an unhealthy lifestyle in either period. In conclusion, adherence to a healthy lifestyle after polypectomy may confer significant benefit for CRC prevention and reduction in all-cause mortality.