Spotlight on CRC screening in older adults

Age-based screening for colorectal cancer (CRC) results in underscreening of older, healthier patients, one study found, while a trial showed that personalized information about CRC risk from a primary care clinician led to more appropriate use of screening.

Two recent studies looked at methods for optimizing colorectal cancer (CRC) screening among older adults.

The first study, published by the American Journal of Gastroenterology on Oct. 27, used data from the National Health Interview Survey on 25,888 community-dwelling adults ages 65 to 84 years. It estimated their 10-year mortality risk and assessed whether they had undergone CRC screening in the past year. Overall, receipt of screening was not associated with predicted 10-year mortality risk, with screening rates of 39.5%, 40.6%, 38.7%, 36.4%, and 35.4% in patients with the lowest to highest quintile of mortality risk, respectively.

More than a quarter (27.9%) of the CRC screening occurred in patients with a life expectancy of less than 10 years, and 50.7% of participants ages 75 to 84 years had a 10-year mortality risk greater than 50% at the time of screening. The proportion of screening that occurred with life expectancy less than 10 years increased by age, from 13.7% in those ages 65 to 69 years to 65.6% among 80- to 84-year-olds. “An age-based approach to CRC screening results in underscreening of older, healthier adults and overscreening of younger adults with chronic conditions,” said the study authors. “Our results suggest that health status and life expectancy may be overlooked in the current CRC screening programs, and personalized screening incorporating individual life expectancy may improve the value of screening.”

Another study, published by JAMA Internal Medicine on Oct. 30, involved an intervention to help veterans ages 70 to 75 years with decisions about CRC screening. A total of 431 average-risk patients who were due for screening (mean age, 71.5 years; 98.4% male) were randomized at the clinician level to either a multilevel intervention including a decision-aid booklet with detailed information on screening benefits and harms, personalized based on their risk (n=258), or a standard screening informational booklet (n=173). Within two weeks of the patient's clinic visit, 62.8% of intervention patients had screening orders placed, compared to 65.9% of controls (adjusted difference, −4.0 percentage points; 95% CI, −15.4 to 7.4 percentage points).

Although the overall rate of screening was similar, when patients were categorized by their likelihood of benefit from CRC screening, the groups differed. Only 59.4% of intervention group patient with the lowest likelihood of benefit (by quartile) were screened, compared to 71.1% in that quartile of the control group. Among those with the highest benefit, 67.6% in the intervention group were screened versus 52.2% of controls (P=0.049 for the interaction). At six months, fewer intervention patients than controls had undergone screening (41.4% vs. 55.9%; adjusted difference, −13.4 percentage points [95% CI, −25.3 to −1.6 percentage points]). “These results suggest that a personalized decision aid, in the context of a multilevel intervention, could be efficacious in enhancing appropriate ordering of CRC screening and in reducing use of CRC screening overall, even in a population that is not highly educated,” said the study authors, who noted that more than a quarter of the study population had limited health literacy.