Chronic arsenic exposure and type 2 diabetes : a meta-analysis

Chronic exposure to inorganic arsenic in drinking water has been associated with Type 2 Diabetes (T2D). However, the association is still inconclusive. We incorporated 33 studies in the analysis including 13 cross-sectional, 6 case-control and 4 cohort studies reporting Odds Ratio (OR), 6 cross-sectional and cohort studies reporting Relative Risk (RR) and 3 mortality studies reporting Standardized Mortality Ratio (SMR). The pooled OR estimate was 1.76 (95% CI: 1.43, 2.17), pooled RR was 1.17 (95% CI: 0.95, 1.45) and pooled SMR was 0.79 (95% CI: 0.59, 1.06), and the overall pooled estimate was 1.55 (95% CI: 1.27, 1.88). The study heterogeneity was very high (I2 = 97% for case-control studies, 47% for cohort studies, and overall 98%). Because of the very high heterogeneity and non-significant results from cohort studies, this analysis provides a limited evidence for an association between arsenic and Type 2 Diabetes (T2D) that needs further validation