Incorporating smoking status into NCI's "Know Your Chances" website can provide clearer estimate of risk of death: JAMA
USA: A cohort study published in JAMA Network Open, using the National Cancer Institute's Know Your Chances, showed that the chance of death due to major causes like lung cancer, heart disease, and all causes combined varies by smoking status.
The researchers reported that The National Cancer Institute's (NCI) website, which can calculate an individual's risk for death over the coming years, is about to get more accurate by including smoking history. According to them, if the smoking status is not considered, the mortality risks are underestimated for smokers and overestimated for nonsmokers,
For example, after 40 years, the observed effect of never versus current smoking on the 10-year chance of death due to all causes approximates adding ten years of age.
"Our findings suggest that mortality estimates failing to account for smoking status are too low for smokers and too high for nonsmokers," Steven Woloshin, Lisa Schwartz Foundation for Truth in Medicine, Norwich, Vermont, and colleagues wrote in their study.
To make wise decisions about the health risks they face, people require information about the magnitude of threats and the context, such as how risks compare. Such information is often presented by race, age, and sex but rarely accounts for smoking status, a significant risk factor for many death causes. Therefore, Woloshin and the team aimed to update the National Cancer Institute's Know Your Chances website to present mortality estimates for a broad set of causes of death and all causes combined by smoking status in addition to sex, age, and race.
The researchers calculated mortality estimates using life table methods with the National Cancer Institute's DevCan software package, combining data from the National Health Interview Survey–Linked Mortality Files, the US National Vital Statistics System, Cancer Prevention Study II, National Institutes of Health–AARP (American Association of Retired Persons), Women's Health Initiative, and Health Professions follow-up studies.
Age-conditional probabilities of dying due to various causes and all causes combined were measured, accounting for competing death causes, for people aged 20 to 75 years over the next 5, 10, or 20 years by race, sex, and smoking status. The analysis included 954 029 individuals aged 55 or older (55.8% women).
The authors reported the following findings:
- Regardless of sex or race, for never-smokers, coronary heart disease represented the highest 10-year chance of death after about 50 years of age, which is higher than for any malignant neoplasm.
- Among current smokers, the 10-year chance of death due to lung cancer was almost as high as for coronary heart disease in each group.
- For Black and White female current smokers aged from the mid-40s onward, the 10-year probability of death due to lung cancer was substantially higher than for breast cancer.
- After 40 years of age, the observed effect of never vs current smoking on the 10-year chance of death due to all causes was approximated by adding ten years of age.
- After 40 years of age, when conditioning on smoking status, mortality risk for Black individuals was approximately that of White individuals five years older.
Using the life table methods and accounting for competing risks, the revised Know Your Chances website presents age-conditional mortality estimates according to smoking status for a broad set of causes in the context of other conditions and all-cause mortality.
"Findings from the cohort study suggest that failing to account for smoking status leads to an inaccurate mortality estimate for many causes—namely, they are too low for smokers and too high for nonsmokers," the authors concluded.
Reference:
Woloshin S, Landsman V, Miller DG, Byrne J, Graubard BI, Feuer EJ. Updating the Know Your Chances Website to Include Smoking Status as a Risk Factor for Mortality Estimates. JAMA Netw Open. 2023;6(6):e2317351. doi:10.1001/jamanetworkopen.2023.17351
