Association between whole blood mercury and glucose intolerance among adult Inuit in Greenland

Environ Res. 2015 Nov;143(Pt A):192-7. doi: 10.1016/j.envres.2015.10.013. Epub 2015 Oct 24.

Abstract

Objectives: The Arctic diet is partly constituted by traditional food characterized by top predator animals such as whales, walrus, and seals with high mercury content. Mercury exposure has been associated with glucose intolerance in Western populations. We studied the association between whole blood mercury and glucose intolerance in a highly exposed non-Western population

Methods: Cross-sectional study of 2640 Inuit (18+ years) with information on ancestry, smoking, waist circumference, total energy intake, and physical activity. Mercury, fasting- and 2-h plasma glucose, insulin, and c-peptide were measured in blood. Fasting participants without diabetes were classified into normal glucose tolerance, impaired glucose tolerance, impaired fasting glycemia, or type 2 diabetes. We calculated hepatic insulin resistance with homoeostatic model assessment - insulin resistance index, peripheral insulin sensitivity by ISI0,120., and relative beta cell function by c-peptide/insulin ratio. We conducted adjusted linear- and logistic regression analyses.

Results: For an increase in whole blood mercury of 5 µg/L we found a positive association with fasting glucose [% change=0.25 (95% CI: 0.20; 0.30); p<0.001], and 2-h glucose [% change=0.23 (95% CI: 0.05; 0.40); p=0.01]. Mercury was weakly associated with impaired fasting glycemia [OR=1.03 (95% CI: 1.02; 1.05)], and type 2 diabetes [OR=1.02 (95% CI: 1.01; 1.04)].

Conclusion: While the study found a weak but statistically significant association between whole blood mercury and both impaired fasting glycemia and type 2 diabetes, no associations were found with measures of underlying disturbances in glucose homoeostasis.

Keywords: Glucose intolerance; Inuit; Type 2 diabetes; Whole blood mercury.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Blood Glucose / analysis
  • Cross-Sectional Studies
  • Diabetes Mellitus, Type 2 / blood
  • Diabetes Mellitus, Type 2 / epidemiology
  • Diabetes Mellitus, Type 2 / etiology*
  • Diet
  • Energy Intake
  • Environmental Exposure / analysis*
  • Glucose Intolerance / blood
  • Glucose Intolerance / epidemiology
  • Glucose Intolerance / etiology*
  • Glucose Tolerance Test
  • Greenland / epidemiology
  • Humans
  • Inuit* / statistics & numerical data
  • Logistic Models
  • Mercury / blood*
  • Middle Aged
  • Motor Activity
  • Surveys and Questionnaires
  • Water Pollutants, Chemical / blood*

Substances

  • Blood Glucose
  • Water Pollutants, Chemical
  • Mercury