Author(s): XIAO, H., XIAOSHENG, D., MINGYANG, B., FEI, W., Institution: PEKING UNIVERSITY, Country: CHINA, Abstract-ID: 248

INTRODUCTION:
Cadmium is a widespread environmental pollutant associated with various adverse health outcomes. Physical activity (PA) may play the potential moderating role in associations between blood cadmium (BC) and mortality risk. This study aims to examine: (1) the associations between PA, BC and all-cause mortality, cardiovascular disease (CVD) mortality, or cancer mortality risk; and (2) the counteracting effect of different PA levels on the risk of mortality caused by BC.
METHODS:
We analyzed data from the National Health and Nutrition Examination Survey (NHANES) 2007-2018, including 22,821 adults. PA levels were assessed using the Global Physical Activity Questionnaire, and BC was measured by inductively coupled plasma mass spectrometry. Cox proportional hazards models and restricted cubic spline models (RCS) were employed for statistical analysis.
RESULTS:
After adjusting for all covariates, compared with the inactive PA group, the insufficiently active PA or sufficiently active PA group had a 33% or 47% lower risk of all-cause mortality, a 35% or 44% lower risk of CVD mortality, and a 32% or 31% lower risk of cancer mortality, respectively. Compared with the minimal blood cadmium level (Min-BCL) group, the high blood cadmium level (H-BCL) group had a 101% higher risk of all-cause mortality, a 72% higher risk of CVD mortality, and a 97% higher risk of cancer mortality. When combining PA and BC, compared with the Min-BCL group, the H-BCL respectively combined with insufficiently active PA or sufficiently active PA had a 103% or 46% higher risk of all-cause mortality, a 115% or 56% higher risk of cancer mortality. while no significant associations were observed between the combinations of H-BCL with insufficiently active PA or sufficiently active PA and the risk of CVD mortality. RCS analysis revealed that, for participants engaging inactive PA, insufficiently active PA or sufficiently active PA, the blood cadmium levels (BCLs) at HR = 1 were 0.07, 0.25, or 0.36 ug/L for all-cause mortality; 0.07, 0.29, or 0.36 ug/L for CVD mortality; and 0.18, 0.36, or 0.36 ug/L for cancer mortality.
CONCLUSION:
Both insufficiently active PA and sufficiently active PA can decrease the risk of all-cause, CVD, or cancer mortality, while H-BCL can increase these mortality risks. Importantly, PA can moderate the associations of BC and these mortality risks. We recommend promoting PA as a potential public health strategy to reduce cadmium-related mortality risks.