The weighted average age of study participants was 43.3 years, and 61.5% of participants were women. Weighted prevalence rates indicated that 28% of Inuit in the regions surveyed were overweight, whereas 35.0% were obese and 43.8% had an at-risk waist (). Smoking was highly prevalent, with 68.8% of the population smoking, and 29.2% smoking more than 10 cigarettes per day (). Past-year alcohol consumption was reported by 71.6% of participants younger than 50 years and 38.9% of those 50 years and older. Elevated triglycerides were identified in 25%, whereas at-risk cholesterol was identified in 8.2%.
Weighted prevalence of metabolic risk factors among Canadian Inuit adults, by age and sex
The prevalence of the hypertriglyceridemic-waist phenotype varied markedly by region. In Inuvialuit Settlement Region, it was 35.2% (weighted; n = 244, 95% CI 27.1–42.7), which was significantly higher than in Nunatsiavut and Nunavut. In Nunatsiavut, it was 23.8% (weighted; n = 255, 95% CI 17.8–29.8), which was significantly higher than in Nunavut, where it was 13.5% (weighted; n = 1439, 95% CI 11.0–15.8) (data not shown; χ2, p ≤ 0.05). Similarly, the prevalence of glycemia (plasma glucose ≥ 6.0 mmol/L) was higher among participants in Inuvialuit Settlement Region (13.9%) compared with Nunatsiavut (3.7%) and Nunavut (6.9%) (χ2, p ≤ 0.05). However, the prevalence of diabetes was similar across regions, with an overall prevalence of 5.1%. While women had a nearly twofold higher prevalence of at-risk waist relative to men, there were no sex differences in the prevalence of the hypertriglyceridemic-waist phenotype. Those 50 years of age or older had a greater prevalence of obesity, an at-risk waist and a hypertriglyceridemic-waist phenotype, but a lower prevalence of smoking and alcohol consumption relative to those less than 50 years of age ().
Striking age differences were noted in glycemia prevalence, with 31.5% of participants 50 years of age and older having a fasting plasma glucose of ≥ 5.6 mmol/L, in contrast to 8.6% among those younger than 50 years (). Diabetes was identified in 12.2% of those aged 50 years or older, in contrast to 1.9% of those younger than 50 years. However, no significant differences in glycemia between men and women were identified (). There was an increased gradient in risk for glycemia (≥ 5.6 mmol/L) by the presence of an at-risk waist or elevated fasting triglyceride level, with the highest proportion of participants with glycemia observed among those with both risk factors who were 50 years of age or older ().
Weighted prevalence of glycemia among Canadian Inuit adults, by age and sex.
Figure 1: Prevalence of glycemia by age group, waist circumference and fasting serum triglyceride level. Glycemia was defined as a fasting glucose level ≥ 5.6 mmol/L or taking medication for diabetes. An at-risk waist was defined as ≥ 102 cm for (more ...)
In weighted multivariable analyses, adjusting for age, sex, region, education, family history of diabetes and use of lipid-lowering medications, the hypertriglyceridemic-waist phenotype was significantly and strongly associated with an elevated fasting glucose (OR 4.3, 95% CI 2.4–7.5), whereas an at-risk waist alone was moderately associated with an elevated fasting glucose (OR 2.2, 95% CI 1.3–3.9) ().
Weighted estimated odds ratios for fasting glycemia ≥ 5.6 mmol/L* and type 2 diabetes† among Canadian Inuit adults, by hypertriglyceridemic-waist phenotype
In a similar multivariable model, the hypertriglyceridemic-waist phenotype was significantly and strongly associated with diabetes (OR 8.6, 95% CI 2.1–34.6), whereas an at-risk waist alone did not show a significant association with diabetes (OR 3.7, 95% CI 0.8–16.8) (). There were no significant age-by-phenotype interactions noted in the multivariable logistic regression models, and additional adjustment for fasting duration did not alter the results. In analyses excluding all participants who reported drinking alcohol in the past year, significant associations between the hypertriglyceridemic-waist phenotype and risk for diabetes persisted, albeit the magnitude of the association was attenuated (Appendix 2, available at www.cmaj.ca/cgi/content/full/cmaj.101801/DC1