Physical Activity and Life Expectancy Free of Cancer: Prospective Evidence From the UK Biobank Study.

Background: Life expectancy free of cancer (LEFC) is a novel measure that considers both morbidity and mortality and could be a useful metric for disease surveillance and risk communication. We aimed to examine the association between physical activity and LEFC in British adults.

Methods: This was a prospective cohort study of 292,559 apparently healthy UK Biobank participants (mean [SD] age, 56.0 [8.1] y, 51% women). Participants were categorized based on self-reported physical activity as "no activity" (0 min/wk), "insufficiently active" (10-599 metabolic equivalent-min/wk), "active" (600-1199 metabolic equivalent-min/wk), and "very active" (>1200 metabolic equivalent-min/wk). Hazard ratios from multistate models for transitions between 3 states (cancer-free, cancer diagnosis, and all-cause mortality) were used to calculate differences in predicted remaining LEFC across physical activity levels for men and women at ages 45 and 65 years.

Results: During a median follow-up of 11.0 years, we recorded 13,143 cancer cases for men and 10,255 for women, and 6488 deaths for men and 3739 for women. At age 45, "insufficiently active," "active," and "very active" had a higher LEFC by 2.35, 2.46, and 2.76 years compared with "no activity," and by 1.44, 1.62, and 1.84 years at age 65. In women, the "insufficiently active," "active," and "very active" had a higher LEFC by 1.09, 1.42, and 1.59 years at age 45, and by 1.25, 1.54, and 1.71 years at age 65.

Conclusions: Engaging in physical activity, even below recommended levels, appears to extend cancer-free years of life. Promoting physical activity is an important strategy for cancer prevention.