Differences in the prevalence of diabetes risk-factors among First Nation, Métis and non-Aboriginal adults attending screening clinics in rural Alberta, Canada

Abstract

Introduction: Populations that are developing (westernizing) are suffering the highest rates of increases in diabetes incidence and prevalence worldwide, with the most notable and documented increases in Canada seen among the First Nations. Less is known about the Métis (mixed blood) or the rural populations in general. To date, no studies have assessed the contributions of ethnicity to diabetes risk-factors. Our objective was to examine diabetes risk factors in First Nations, Métis and non-Aboriginal individuals residing in rural or remote locations, investigating whether ethnicity contributed to any differences.

Methods: From the databases of three separate community-based diabetes screening projects in Alberta we created a unique subject pool of 3148 adults without diabetes (1790 First Nation, 867 Métis, and 491 non-Aboriginals). Age, body mass index (BMI), waist circumference, reported history of gestational diabetes (GDM) or babies over nine pounds (females only), hemoglobin A1c (A1c) fasting plasma glucose (FPG) or random plasma glucose (RPG) were assessed. Chi-square tests and logistic regression analysis were used to identify between-group differences.

Results: The highest mean values for waist circumference (104.7 cm) and BMI (31.2) were found in First Nations subjects (p<0.01). First Nations individuals had the highest prevalence of overweight/obesity (84.4%), abnormal waist circumference (76.8%) and history of GDM (9.0%) (p<0.01). The RPG was also higher in First Nations, but there were no differences between groups with respect to mean FPG and A1c levels, and there were no differences with respect to the prevalence of pre-diabetes or undiagnosed diabetes. Métis (OR 0.80; p = 0.01) and non-Aboriginal individuals (OR 0.62; p< 0.01) were less likely to be obese after age/gender adjustment, compared with First Nations. Métis (OR 0.70; p<0.01) and non-Aboriginals (OR 0.35; p<0.01) were also less likely than the First Nations group to have abnormal waist circumferences. Individuals in the non-Aboriginal group had a lower prevalence of pre-diabetes (OR 0.50; p = 0.01) compared with both the Métis and First Nations groups.

Conclusions: First Nations individuals had more risk factors for diabetes than Métis and non-Aboriginal individuals, although Métis rates appeared intermediate. While these risk-factor differences did not translate to more undiagnosed diabetes or pre-diabetes, they are consistent with known rates of diagnosed diabetes in Alberta.