Pack-Year Smoking History: An Inadequate and Biased Measure to Determine Lung Cancer Screening Eligibility

Area of Science:

• Pulmonary Medicine
• Oncology
• Public Health

Background:

• Pack-year smoking history is a standard but flawed metric for assessing cumulative tobacco exposure.
• Current US Preventive Services Task Force (USPSTF) guidelines for lung cancer screening may exclude high-risk individuals, particularly racial and ethnic minorities, due to reliance on pack-years.
• The effectiveness of using smoking duration as an alternative criterion is not well-established.

Purpose of the Study:

• To evaluate whether a smoking duration criterion improves lung cancer screening eligibility compared to the pack-year criterion.
• To determine if a smoking duration cutoff can reduce racial disparities in lung cancer screening access.

Main Methods:

• Analysis of 49,703 individuals from the Southern Community Cohort Study (SCCS) and 22,126 from the Black Women's Health Study (BWHS).
• Comparison of lung cancer screening eligibility under the current USPSTF guideline (≥20 pack-years) versus a proposed guideline (≥20 years smoking duration).

Main Results:

• The USPSTF guideline identified only 57.6% of Black patients with lung cancer in the SCCS, versus 74.0% of White patients (p < .001).
• The proposed 20-year smoking duration criterion increased eligibility to 85.3% for Black patients and 82.0% for White patients in the SCCS, eliminating the disparity.
• In the BWHS, the duration criterion raised screening eligibility for Black women with lung cancer from 42.5% to 63.8%.

Conclusions:

• A 20-year smoking duration cutoff substantially increases lung cancer screening eligibility for patients.
• This change effectively eliminates racial disparities in screening eligibility between Black and White individuals.
• Smoking duration is a more precise measure of exposure and simpler to calculate than pack-years.