Influence of Age, Health, and Function on Cancer Screening in Older Adults with Limited Life Expectancy

We examined the relationship between cancer screening and life expectancy predictors, focusing on the influence of age versus health and function, in older adults with limited life expectancy.

Longitudinal cohort study SETTING: National Health and Aging Trends Study (NHATS) with linked Medicare claims.

Three cohorts of adults 65+ enrolled in fee-for-service Medicare were constructed: women eligible for breast cancer screening (n = 2043); men eligible for prostate cancer screening (n = 1287); men and women eligible for colorectal cancer screening (n = 3759).

We assessed 10-year mortality risk using 2011 NHATS data, then used claims data to assess 2-year prostate and breast cancer screening rates and 3-year colorectal cancer screening rates. Among those with limited life expectancy (10-year mortality risk > 50%), we stratified participants at each level of predicted mortality risk and split participants in each risk stratum by the median age. We assembled two sub-groups from these strata that were matched on predicted life expectancy: a "younger sub-group" with relatively poorer health/functional status and an "older sub-group" with relatively better health/functional status. We compared screening rates between sub-groups.

For all three cancer screenings, the younger sub-groups (average ages 73.4-76.1) had higher screening rates than the older sub-groups (average ages 83.6-86.9); screening rates were 42.9% versus 34.2% for prostate cancer screening (p = 0.02), 33.6% versus 20.6% for breast cancer screening (p < 0.001), 13.1% versus 6.7% for colorectal cancer screening in women (p = 0.006), and 20.5% versus 12.1% for colorectal cancer screening in men (p = 0.002).

Among older adults with limited life expectancy, those who are relatively younger with poorer health and functional status are over-screened for cancer at higher rates than those who are older with the same predicted life expectancy.