Association of blood cadmium with all-cause and cause-specific mortality in patients with hypertension

Abstract

BackgroundCadmium is a commonly found heavy metal with a prolonged biological half-life, which results in long-term health burden for the population. Prior studies have demonstrated an association between blood cadmium and hypertension. However, few studies examined the relationship between blood cadmium and long-term health outcomes in patients with hypertension. This study aimed to investigate the association of blood cadmium with mortality in patients with hypertension.MethodsThis study analyzed data from the National Health and Nutrition Examination Survey 1999–2012. Complex sampling-weighted multivariate Cox proportional hazards models were used to evaluate the hazard ratios (HRs) of all-cause, cardiovascular, and Alzheimer’s disease mortality in patients with hypertension classified by blood cadmium concentrations’ quantiles.ResultsThe study included 12,208 patients with hypertension with a median follow-up duration of 10.8 years. During this period, there were 4,485 all-cause deaths, including 1,520 cardiovascular deaths and 180 Alzheimer’s disease deaths. Compared with the lowest quintile of blood cadmium (≤0.25 μg/L) group, the highest quintile of blood cadmium (≥0.80 μg/L) group’s adjusted HRs were 1.85 (95% CI, 1.59–2.14) for all-cause mortality, 1.76 (95% CI, 1.33–2.34) for cardiovascular mortality, and 3.41 (95% CI, 1.54–7.51) for Alzheimer’s disease mortality. Additionally, the adjusted HR for cardiovascular mortality was 2.12 (95% CI, 1.36–3.30) in never-smoking patients with hypertension.ConclusionHigher blood cadmium is associated with increased risks of all-cause, cardiovascular, and Alzheimer’s disease mortality in patients with hypertension. The effect of blood cadmium on cardiovascular mortality may be more pronounced in never-smoking hypertensive patients.

Modulation of Adverse Health Effects of Environmental Cadmium Exposure by Zinc and Its Transporters

“…Epidemiological studies implicating Cd exposure as a significant contributor to total global mortality and morbidity can be found in Table 4. In the U.S. hypertension cohort [127], blood Cd levels ≥ 0.80 µg/L were associated with 1.85-, 1.76-, and 3.41-fold increases in the mortality from any causes, CVD, and Alzheimer's disease, respectively. Cd appeared to increase CVD mortality markedly (OR 2.12) among non-smokers who had hypertension [127].…”

“…In the U.S. hypertension cohort [ 127 ], blood Cd levels ≥ 0.80 μg/L were associated with 1.85-, 1.76-, and 3.41-fold increases in the mortality from any causes, CVD, and Alzheimer’s disease, respectively. Cd appeared to increase CVD mortality markedly (OR 2.12) among non-smokers who had hypertension [ 127 ].…”

“…In the U.S. hypertension cohort [ 127 ], blood Cd levels ≥ 0.80 μg/L were associated with 1.85-, 1.76-, and 3.41-fold increases in the mortality from any causes, CVD, and Alzheimer’s disease, respectively. Cd appeared to increase CVD mortality markedly (OR 2.12) among non-smokers who had hypertension [ 127 ]. In the other two U.S. diabetes and CKD cohorts, urinary Cd levels > 0.60 μg/L were associated with a 49% increase in all-cause mortality among those with diabetes [ 128 ], while urinary Cd levels ≥ 0.60 μg/g creatinine were associated with a 75% increase in deaths from any cause among those with CKD [ 129 ].…”

The association between cadmium exposure and axonal injury biomarker, serum neurofilament light chain levels in US adults

“…Some epidemiological studies have shown that long-term, even low levels of cadmium exposure are closely associated with neurological diseases, including multiple sclerosis [9], ischemic stroke [10], and cognitive decline [11][12][13][14]. Additionally, higher cadmium exposure is associated with increased risk of Alzheimer's disease mortality [15][16][17]. However, several studies show there is no relationship between cadmium exposure and cognitive function [18][19][20].…”