WEDNESDAY, Oct. 12, 2022 (HealthDay News) -- Sigmoidoscopy has a significant and sustained effect on colorectal cancer (CRC) incidence and mortality, according to a study published online Oct. 11 in the Annals of Internal Medicine.
Frederik E. Juul, M.D., from Oslo University Hospital in Norway, and colleagues examined the 15-year effect of sigmoidoscopy screening on CRC incidence and mortality in a pooled analysis of four large-scale randomized trials involving women and men aged 55 to 64 years at enrollment. The analyses included 274,952 persons: 137,493 and 137,459 in the screening and usual-care groups, respectively.
Screening attendance varied from 58 to 84 percent. The researchers found that the rate difference for CRC incidence was 0.51 cases per 100 persons after 15 years and the incidence rate ratio (IRR) was 0.79 (95 percent confidence interval, 0.75 to 0.83). For CRC mortality, the rate difference was 0.13 deaths per 100 persons and the mortality rate ratio (MRR) was 0.80 (0.72 to 0.88). For CRC incidence and mortality, women had less benefit from screening than men (IRR, 0.84 [0.77 to 0.91] and 0.75 [0.70 to 0.81], respectively; MRR, 0.91 [0.77 to 1.17] and 0.73 [0.64 to 0.83], respectively). No significant difference in screening effect was seen between those aged 55 to 59 years and those aged 60 to 64 years.
"A single screening examination with sigmoidoscopy is effective in reducing CRC incidence in women and men, although the screening benefits seem to be less in women than men," the authors write.