Healthy lifestyle is inversely associated with mortality in cancer survivors: Results from the Third National Health and Nutrition Examination Survey (NHANES III)

Abstract

Individual lifestyle behaviors have been associated with prolonged survival in cancer survivors, but little information is available on the association between combined lifestyle behaviors and mortality in this population. Data from 522 cancer survivors participating in the Third National Health and Nutrition Examination Survey (NHANES III) were analyzed. Behaviors pertaining to lifetime healthy body weight maintenance, physical activity, smoking, diet quality (assessed by the Healthy Eating Index) and moderate alcohol consumption were combined in a lifestyle score (range 0-5). Cox proportional hazards regression models were used to calculate multivariable-adjusted hazard ratios (HR) and 95% confidence intervals (CI). Both in continuous and categorical models, the lifestyle score was statistically significantly associated with lower mortality in the total study population (HRcontinuous = 0.81, 95% CI: 072, 0.90, per 1 unit increase; HR1-2 vs. 0 total = 0.71, 95% CI: 0.56, 0.92; HR3-5 vs. 0 total = 0.57, 95% CI: 0.38, 0.85, in the fully adjusted model) and in sex-specific analyses. Cancer survivors with high or moderate lifestyle score had lower risk of premature death compared to survivors with zero lifestyle score. Future studies are required in order to verify our findings and to investigate underlying mechanisms of the mortality-adherence association.

Fig 1. Hazard ratios for adherence to each healthy lifestyle behavior and mortality.

Adherence was defined as: Never smoker, lifetime healthy body weight maintenance (expressed as lifetime highest body mass index between 18.5 and 24.9 kg/m²), participation in moderate to vigorous physical activity 5 or more times per week, moderate alcohol consumption (5-15g per day for females and 5-30g per day for males) and high diet quality (expressed as HEI score in the highest 40% of the study population distribution (HEI score > 69.3)). Adjusted for: age at study entry (years), sex, race/ethnicity (Non-Hispanic white, Non-Hispanic black, Mexican-American, Other), time between diagnosis and inclusion in the study (years), marital status (married/living together, never married/widowed or divorced/separated), socioeconomic status (poor, near poor, middle income, higher income or unknown), daily energy consumption (kcal/d) and type of cancer diagnosed (female cancers, male cancers, gastrointestinal cancers or other cancers).