Association between oxidative balance score and mortality: Prospective cohort study in a representative US population

We explored the relationship between the oxidative balance score (OBS) and all-cause, as well as cause-specific mortality, within a large and nationally representative sample. A total of 30,074 adults participated in this prospective study, utilizing data from the National Health and Nutrition Examination Survey cycles spanning 1999 to 2018 in the United States. Mortality outcomes were determined through linkage to National Death Index records up to December 31, 2019. OBS was computed based on 16 dietary and 4 lifestyle components. Cox proportional hazards models and restricted cubic splines were employed to estimate associations between OBS and mortality across all-cause, cancer, cardiovascular disease (CVD), and respiratory disease. Over the mean 10.3 years of follow-up, we observed 3561 deaths. In comparison to the lowest OBS quartile, individuals in the highest quartile exhibited a significantly reduced multi-adjusted hazard ratio of 0.66 (95% confidence interval [CI]: 0.56-0.78), 0.56 (95% CI: 0.40-0.77), and 0.43 (95% CI: 0.22-0.83) for all-cause, cancer, and respiratory disease mortality, respectively. However, no significant association was found for CVD mortality (0.80 [95% CI: 0.59-1.09]). Restricted cubic splines demonstrated a linear association. Sensitivity analysis and subgroup analysis confirmed the stability of results for all-cause and cancer mortality, while respiratory disease mortality might be influenced by chronic disease. A robust negative correlation was identified between OBS and all-cause, cancer, and respiratory disease mortality, with no such association observed for CVD mortality. This study provides insights into enhancing overall antioxidant dietary and lifestyle practices among adults.