1988

Background/Aim: Ingested inorganic arsenic (iAs) is eliminated through urine mainly as monomethylarsonic acid (MMA) and dimethylarsinic acid (DMA). %MMA and the primary methylation ratio [PMR] (MMA/iAs), have been negatively associated with type 2 diabetes mellitus (T2DM). iAs metabolism is also related to arsenic exposure magnitude, genetic and dietary factors, that may influence the relationship between iAs and T2DM, however, insufficient evidence is available. Our aim was to assess T2DM association with iAs metabolism, considering the dietary intake of selected micronutrients (methionine, choline, folate, selenium and vitamin B12) and polymorphisms (AS3MT Met287Thr and AS3MT G12390C). Methods: We conducted a cross-sectional study with 227 diabetic women matched by age (±5 years) with two non-diabetics (n=454). They were identified in a population-based control group of a previous breast cancer study in northern Mexico. Women were interviewed with a validated semi-quantitative food frequency questionnaire. Urinary arsenic metabolites were measured by High Performance Liquid Chromatography coupled with mass spectrometry and iAs metabolism was assessed by metabolites percentages and ratios. Genotypes were determined by allelic discrimination. Results: Total urinary arsenic (TAs) ranged from 1.24 to 99.97 µg/L. Diabetics had significantly lower %MMA, PMR, choline and selenium intake than non-diabetics. TAs, %Asi⁺³, %Asi⁺⁵, %DMA, second methylation ratio [SMR] (DMA/MMA) and selected polymorphisms were not significantly different between diabetics and non-diabetics. We did not find an association between T2DM and iAs metabolism. Polymorphisms and dietary variables of interest did not modify nor confuse the potential association assessed. Other T2DM co-factors, such as hypertension and waist-hip ratio were significantly associated with T2DM (OR_{Hypertension YesvsNo}: 3.50, 95%CI: 2.46, 4.97; OR_{Waist-hip ratio >0.91vs≤0.91}: 1.97, 95%IC: 1.37, 2.82). Conclusions: Our findings do not support an association between iAs metabolism and T2DM, but it is important to reduce the exposure considering iAs has been considered a risk factor for cancer and cardiovascular diseases.