FIT test completion, yield similar among patients 45 to 49 years and 50-year-olds
In a study of patients completing their first fecal immunochemical test (FIT), those ages 45 to 49 years had a lower adenoma detection rate but a similar rate of colorectal cancer as patients who were 50 years of age when they first underwent screening.
Fecal immunochemical test (FIT) completion and yield rates were similar in people ages 45 to 49 years and those 50 years of age, a study found.
Researchers conducted a retrospective cohort study in a large health care system distributing 267,732 FIT kits in three states from January to September 2022. For both age groups, this was their first CRC screening invitation. Outcomes included FIT completion within three months, FIT positivity, receipt of colonoscopy within three months after a positive FIT result, and colonoscopy yield. Results were published Oct. 22 by Annals of Internal Medicine.
The study included 213,928 (79.9%) patients ages 45 to 49 years and 53,804 (20.1%) who were 50 years of age. Overall, FIT completion was slightly higher in patients ages 45 to 49 years (38.9% vs. 37.5%; adjusted risk ratio [aRR], 1.05 [95% CI, 1.04 to 1.06]), although in one of the three states (Colorado), those ages 45 to 49 years were substantially less likely to complete a FIT (30.7% vs. 40.2%; aRR, 0.77 [95% CI, 0.73 to 0.80]). The study authors noted that this may be explained by a care gap in the electronic health record that led physicians to recommend colonoscopy before FIT became an option. Overall, FIT positivity was lower in patients ages 45 to 49 years (3.6% vs. 4.0%; aRR, 0.91 [95% CI, 0.84 to 0.98]). The rate of colonoscopy after a positive FIT result was similar between groups (64.9% vs. 67.4%; aRR, 1.00 [95% CI, 0.94 to 1.05]).
The adenoma detection rate was lower in the younger group (58.8% vs. 67.7%; aRR, 0.88 [95% CI, 0.83 to 0.95]), but yields were similar for adenoma with advanced histology (13.2% vs. 15.9%; aRR, 0.86 [95% CI, 0.69 to 1.07]), polyp with high-grade dysplasia (3.4% vs. 5.1%; aRR, 0.68 [95% CI, 0.44 to 1.04]), sessile serrated lesion (10.3% vs. 11.7%; aRR, 0.92 [95% CI, 0.71 to 1.21]), and colorectal cancer (2.8% vs. 2.7%; aRR, 1.10 [95% CI, 0.62 to 1.96]).
Overall, study results suggest that patients ages 45 to 49 years have similar colorectal cancer risk as those age 50 years, the study authors wrote.
“Also, the generally similar yields in the 2 age groups as well as across age years versus age 50 years provide strong support for lowering the start of screening initiation to age 45 years and for using a noninvasive test to select patients for colonoscopy in this younger age group,” the authors concluded. “In addition, our findings support the conclusions of cost models demonstrating that annual FIT screening starting at age 45 years yields a similar number of quality-adjusted life-years compared with the strategy of colonoscopy every 10 years, but at a much lower cost.”