Older adults with shorter life expectancies may receive less benefit from colorectal cancer screening than younger, healthier patients.
Dr Cary Gross and colleagues from Connecticut determined the degree to which life expectancy after diagnosis of an early-stage cancer varies according to age or coexisting chronic illness.
The team conducted a retrospective cohort study, and assessed a population-based cancer registry with linked administrative claims data.
Patients 67 years of age or older who received a diagnosis of colorectal cancer from 1993 through 1999 were included in the analyses.
The research team identified chronic conditions by searching Medicare claims.
|Life expectancy after cancer diagnosis with no other chronic illnesses was 10 to 14 years|
|Annals of Internal Medicine|
Using a life-table approach, the researchers quantified the degree to which life expectancy associated with each cancer stage at diagnosis varied with patient age, sex, and burden of chronic conditions.
The final study sample consisted of 35,755 patients.
After accounting for cancer stage at diagnosis, the researchers found that life expectancy was strongly related to both age and the burden of chronic illness.
Among men who received a diagnosis of stage I cancer at 67 years of age, life expectancy decreased from 19 years for patients with no chronic conditions to 12 years for those with 1 or 2 conditions.
The team noted that the life expectancy decreased further to 8 years for those with 3 or more conditions.
The researchers noted a similar trend among female counterparts, with life expectancy decreasing from approximately 23 years to 16 years, and 7 years for the 3 chronic condition groups, respectively.
For men and women 81 years of age with no chronic illnesses, life expectancy after stage I cancer diagnosis was 10 years, and 14 years, respectively.
The researchers acknowledge that administrative claims may not identify all chronic conditions.
The team also highlights that life expectancy estimates at the population level are averages and, perhaps it may not accurately predict the life expectancy of individual patients.
Dr Gross' team concludes, “Coexisting chronic illness is associated with a substantial reduction in life expectancy after diagnosis of early-stage colorectal cancer.”
“Physicians should consider this when deciding whether to screen older persons.”