Arsenic exposure and incidence of Type 2 Diabetes in Southwestern American Indians
Kim, N. H., Mason, C. C., Nelson, R. G., Afton, S., Essader, A., Medlin, J., Levine, K., Hoppin, J. A., Lin, C., Knowler, W. C., & Sandler, D. P. (2013). Arsenic exposure and incidence of Type 2 Diabetes in Southwestern American Indians. American Journal of Epidemiology, 177(9), 962-969. https://doi.org/10.1093/aje/kws329
Association of urinary arsenic concentration with incident diabetes was examined in American Indians from Arizona who have a high prevalence of type 2 diabetes and were screened for diabetes between 1982 and 2007. The population resides where drinking water contains arsenic at concentrations above federally recommended limits. A total of 150 nondiabetic subjects aged >= 25 years who subsequently developed type 2 diabetes were matched by year of examination and sex to 150 controls who remained nondiabetic for >= 10 years. Total urinary arsenic concentration, adjusted for urinary creatinine level, ranged from 6.6 mu g/L to 123.1 mu g/L, and inorganic arsenic concentration ranged from 0.1 mu g/L to 36.0 mu g/L. In logistic regression models adjusted for age, sex, body mass index, and urinary creatinine level, the odds ratios for incident diabetes were 1.11 ( 95% confidence interval ( CI): 0.79, 1.57) and 1.16 ( 95% CI: 0.89, 1.53) for a 2-fold increase in total arsenic and inorganic arsenic, respectively. Categorical analyses suggested a positive relationship between quartiles of inorganic arsenic and incident diabetes ( P = 0.056); post-hoc comparison of quartiles 2-4 with quartile 1 revealed 2-fold higher odds of diabetes in the upper quartiles ( OR = 2.14, 95% CI: 1.19, 3.85). Modestly elevated exposure to inorganic arsenic may predict type 2 diabetes in American Indians. Larger studies that include measures of speciated arsenic are required for confirmation
