Association between whole blood mercury and glucose intolerance among adult Inuit in Greenland.
OBJECTIVE
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)].


CONCLUSIONS
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.
Center for Health Research in Greenland, National Institute of Public Health, University of Southern Denmark, Øster Farimagsgade 5A, 2. Fl., 1353 Copenhagen C, Denmark. Electronic address: charl.jeppesen@gmail.com.
Charlotte
C
Jeppesen
Center for Health Research in Greenland, National Institute of Public Health, University of Southern Denmark, Øster Farimagsgade 5A, 2. Fl., 1353 Copenhagen C, Denmark; Institut universitaire de cardiologie et de pneumologie de Québec, Pavillon de recherche clinique, 2725 Chemin Sainte-Foy, Quebec, Canada G1V 4G5.
Beatriz
B
Valera
Center for Health Research in Greenland, National Institute of Public Health, University of Southern Denmark, Øster Farimagsgade 5A, 2. Fl., 1353 Copenhagen C, Denmark.
Nina O
NO
Nielsen
Center for Health Research in Greenland, National Institute of Public Health, University of Southern Denmark, Øster Farimagsgade 5A, 2. Fl., 1353 Copenhagen C, Denmark; Greenland Centre for Health Research, University of Greenland, Greenland.
Peter
P
Bjerregaard
Center for Health Research in Greenland, National Institute of Public Health, University of Southern Denmark, Øster Farimagsgade 5A, 2. Fl., 1353 Copenhagen C, Denmark; Steno Diabetes Center A/S, Niels Steensens Vej 2-4, DK-2820 Gentofte, Denmark.
Marit E
ME
Jørgensen
D000328:Adult; D001786:Blood Glucose / Q000032:analysis; D003430:Cross-Sectional Studies; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000453:epidemiology / Q000209:etiology*; D004032:Diet; D002149:Energy Intake; D004781:Environmental Exposure / Q000032:analysis*; D018149:Glucose Intolerance / Q000097:blood / Q000453:epidemiology / Q000209:etiology*; D005951:Glucose Tolerance Test; D006116:Greenland / Q000453:epidemiology; D006801:Humans; D004930:Inuit / Q000706:statistics & numerical data; D016015:Logistic Models; D008628:Mercury / Q000097:blood*; D008875:Middle Aged; D009043:Motor Activity; D011795:Surveys and Questionnaires; D014874:Water Pollutants, Chemical / Q000097:blood*
D001786:Blood Glucose; D014874:Water Pollutants, Chemical; D008628:Mercury
Glucose intolerance; Inuit; Type 2 diabetes; Whole blood mercury