Cadmium exposure is associated with reduced grip strength in US adults

Muscle strength is a strong predictor of all-cause mortality in the general population. Recent studies have shown an association between environmental pollution and declined grip strength. No previous research has evaluated the specific association between cadmium exposure, a well-known risk factor of several chronic diseases, and muscle strength. Cross-sectional study among 4,197 individuals aged ≥40 years, who participated in the National Health and Nutrition Examination Survey (NHANES) 2011–2014, provided data on grip strength, and had either blood or urine cadmium determinations. Grip strength was measured using a Takei digital handgrip dynamometer, and combined grip strength was calculated as the sum of the largest reading from each hand. Median (interquartile range) concentrations of blood (BCd) and creatinine-corrected urine cadmium (Cr–UCd) were 0.32 μg/L (0.20–4.56) and 0.27 μg/g (0.15–0.46), respectively. After adjusting for sociodemographic, anthropometric, health-related behavioral, and clinical risk factors, and serum creatine phosphokinase concentrations, the highest (vs lowest) quartile of BCd was associated with a reduction in combined grip strength of 1.93 kg (95% confidence interval [CI]: −3.51, −0.34), p-trend <0.001. The corresponding values comparing Cr–UCd quartiles 4 vs 1 were −3.24 kg (95% CI: −5.68, −0.79), p-trend <0.001. These results were consistent across socio-demographic and clinical subgroups. In the US adult population, higher cadmium exposure was associated with decreased grip strength. These results may have important public health implications given the widespread cadmium exposure.