TABLE 30
Key epidemiological studies on metabolic syndrome in humans in relation to iAs exposure.
| Reference study population design | Outcome definition | Population size (n) case/control | Arsenic exposure | Results | Additional information/confounders |
|---|---|---|---|---|---|
|
Chen et al. (2012) Southwestern Taiwan Cohort study Recruited in 1990 and follow‐up in 2002–03 | Metabolic syndrome (MetS) based on criteria for fasting plasma glucose, triglycerides, high density lipoprotein, increased systolic of diastolic blood pressure and waist girth | 247 individuals, 111 with MetS and 136 with no MetS |
u‐As (mean) at follow‐up No Mets – Mets AsIII (μg/g creatinine) 3.79–4.12 AsV 1.78–1.47 iAs 5.57–5.58 MMA 4.51–3.08 DMA 32.79–35.52 u‐tiAs 42.87–44.19 iAs% 17.2–16.8 AsIII% 10.1–10.4 AsV% 7.3–6.9 MMA% 10.6–9.4 DMA% 72.3–73.5 PMI 0.92–0.75 (MMA/(AsIII+AsV)) SMI 16.12–19.98 (DMA/MMA) As concentrations in well‐water (μg/L) 570–684 Cumulative As exposure, CAE (mg/(L*years)) 13.96–17.71 |
Age‐adjusted p‐values No Mets versus Mets AsIII 0.79 AsV 0.29 iAs 0.97 MMA 0.03 DMA 0.42 u‐tiAs 0.66 iAs% 0.98 AsIII% 0.98 AsV% 0.99 MMA% 0.06 DMA% 0.37 PMI 0.06 SMI 0.42 Adjusted OR (95% CI) Highest versus lowest tertile In well water 1.24 (0.65–2.37) CAE 1.73 (0.72–4.19) In urine: AsIII% 0.78 (0.41–1.49) AsV% 0.80 (0.43–1.49) MMA% 0.35 (0.18–0.66) DMA% 2.01 (1.05–3.86) PMI 0.39 (0.20–0.76) SMI 2.61 (1.35–5.08) | Adjusted for age and betel nut chewing |
|
Kazemifar et al. (2020) Qazvin province, Iran Cross‐sectional | Metabolic syndrome using the criteria suggested by the Third National Cholesterol Education Program (NCEP) report | 45 with metabolic syndrome and 87 without |
Urinary concentrations, Means, (μg/L) cases – controls iAsIII 2.32–2.36 iAsV 0.69–0.74 iAs 3.01–3.10 MMA 2.90–3.12 DMA 15.53–14.15 %iAs 14.45–14.46%MMA 13.69–15.33 %DMA 71.85–68.19 MMA/iAs 0.97–0.99 DMA/MMA 5.28–4.59 |
p‐values for comparisons between cases and controls iAsIII 0.43 iAsV 0.14 iAs 0.15 MMA 0.06 DMA 0.07 %iAs 0.017%MMA < 0.001 %DMA < 0.001 MMA/iAs 0.45 DMA/MMA < 0.001 Adjusted OR (95% CI) by unit increase %iAs 0.90 (0.75–1.08) %MMA 0.76 (0.59–0.97) %DMA 1.18 (1.07–1.39) MMA/iAs 0.39 (0.04–3.73) DMA/MMA 1.86 (1.05–3.31) | Adjusted for age and BMI |
|
Spratlen et al. (2018) Strong Heart Family Study, USA Follow‐up study (Baseline visits 1998–99 and 2001–03 and Follow‐up visits 2001–03 and 2006–09) | Metabolic syndrome was characterised according to the National Cholesterol Education Program Adult Treatment Panel III guidelines |
1047 participants with no MetS at baseline 338 developed MetS during follow‐up |
Urinary concentrations at baseline Medians, No MetS – MetS u‐tiAs (μg/L) 6.3–7.0 iAs% 10.0–9.9 MMA% 16.0–14.2 DMA% 72.1–75.1 |
p‐values for comparisons between cases and controls u‐tiAs (μg/L) 0.21 iAs% 0.01 MMA% < 0.001 DMA% < 0.001 Adjusted RR (95% CI) per IQR increase u‐tiAs 1.03 (0.90–1.18) per 5% increase iAs% 0.94 (0.88–1.01) MMA% 0.87 (0.79–0.95) DMA% 1.07 (1.02–1.12) |
Adjusted for urinary creatinine concentration, sex, region, education, alcohol, smoking, kidney function and BMI. |
|
Pace et al. (2018) NHANES, USA Cross‐sectional |
A diagnose was given based on the following variables: Fasting glucose, systolic or diastolic blood pressure, triglycerides, waist circumferences, HDL‐cholesterol |
957 individuals participated whereof 331 had MetS |
Urinary As species, mean (μg/L) iAsIII: 0.51 MMA III + V: 0.63 DMA III + V: 4.68 %iAs: 9.68%MMA: 11.69 %DMA: 78.63 MMA/iAs: 1.89 DMA/MMA: 10.44 |
p‐values obtained from adjusted logistic regression Gender specific analyses Men ‐ Women %iAs 0.950–0.977%MMA 0.021–0.153 %DMA 0.150–0.078 MMA/iAs 0.173–0.876 DMA/MMA 0.152–0.037 | Adjusted for age, Poverty Income Ratio, ethnicity, smoking |
Abbreviations: As, arsenic; AsIII, arsenite; AsV, arsenate; BMI, body mass index; CAE, cumulative arsenic exposure; CI, confidence interval; DMA, sum of dimethylarsinite and dimethylarsinate; DMA(III), dimethylarsinous acid; DMA(V), dimethylarsinic acid; HDL, high‐density lipoprotein; iAs, inorganic arsenic; iAsIII, arsenite; iAsV, arsenate; IQR, interquartile range; MMA, sum of monomethylarsonous acid and monomethylarsonic acid; MMA(III), monomethylarsonous acid; MMA(V), monomethylarsonic acid; MetS, metabolic syndrome; n, number; NCEP, National Cholesterol Education Program; OR, odds ratio; NHANES, National Health and Nutrition Examination Survey; PMI, primary methylation index; RR, risk ratio; SMI, secondary methylation index; u‐As, urinary arsenic; USA, United States of America; u‐tiAs, total urinary iAs (sum of iAs and its methylated metabolites MMA and DMA).