Fasting triglycerides as a predictor of incident diabetes, insulin resistance and ß-cell function in a Canadian First Nation.

BACKGROUND: Diabetes prevalence is substantially higher among Canadian First Nations populations than the non-First Nation population. Fasting serum triglycerides have been found to be an important predictor of incident diabetes among non-indigenous populations. However, there is a great need to understand diabetes progression within specific ethnic groups, particularly First Nations populations. OBJECTIVE: The purpose of this study was to test for an association between fasting serum triglycerides and incident diabetes, changes in insulin resistance and changes in ß-cell function in a Manitoba First Nation cohort. METHODS: Study data were from two diabetes screening studies in Sandy Bay First Nation in Manitoba, Canada, collected in 2002/2003 and 2011/2012. The cohort was composed of respondents to both screening studies (n=171). Fasting blood samples and anthropometric, health and demographic data were collected. A generalised linear model with Poisson distribution was used to test for an association between fasting triglycerides and incident diabetes. RESULTS: There were 35 incident cases of diabetes among 128 persons without diabetes at baseline. Participants who developed incident type 2 diabetes were significantly older and had significantly higher body mass index (BMI; p=0.012), total cholesterol (p=0.007), fasting triglycerides (p<0.001), and Homeostatic Model Assessment of Insulin Resistance (HOMA-IR) (p<0.001). Fasting triglyceride level was found to be a statistically significant positive predictor of incident diabetes independent of age, sex and waist circumference at baseline. Participants with triglycerides in the highest tertile (≥2.11 mmol/l) had a 4.0-times higher risk of developing incident diabetes compared to those in the lowest tertile (p=0.03). Notably, neither waist circumference nor BMI were significant predictors of incident diabetes independent of age, sex and triglycerides. CONCLUSION: Fasting triglycerides may be useful as a clinical predictor of insulin resistance and diabetes development among First Nations populations. Unlike other ethnic groups, BMI and waist circumference may be less important factors in diabetes development.

Incident diabetes, hypertension and dyslipidemia in a Manitoba First Nation.

BACKGROUND: Diabetes and diabetes complications are substantially higher among Canadian First Nations populations compared with the general Canadian population. However, incidence data using detailed individual assessments from a population-based cohort have not been undertaken. OBJECTIVE: We sought to describe incident diabetes, hypertension and dyslipidemia in a population-based cohort from a Manitoba Ojibway First Nation community. DESIGN: Study data were from 2 diabetes screening studies in Sandy Bay First Nation in Manitoba, Canada, collected in 2002/2003 and 2011/2012. The cohort comprised of respondents to both screening studies (n=171). Health and demographic data were collected using a questionnaire. Fasting blood samples, blood pressure and anthropometric data were also collected objectively. Incident diabetes, hypertension and dyslipidemia were determined. Generalized linear models with Poisson distribution were used to estimate risk of incident diabetes and cardiometabolic conditions according to age and sex. RESULTS: There were 35 (95% CI: 26, 45) new cases of diabetes among 128 participants without diabetes at baseline (27 or 3.3% per year). While participants who were 50 years and older at baseline had a significantly higher risk of incident diabetes at follow-up compared with participants aged 18-29 at baseline (p=0.012), more than half of the incident cases of diabetes occurred among participants aged less than 40 at baseline. There were 28 (95% CI: 20, 37) new cases of dyslipidemia at follow-up among 112 without dyslipidemia at baseline (25%). There were 36 (95% CI: 31, 42) new cases of hypertension among 104 participants without hypertension at baseline (34.6%). Women had half the risk of developing hypertension compared with men (p=0.039). CONCLUSIONS: Diabetes incidence is very high, and the number of new cases among those younger than 40 is a concern. Additional public health and primary care efforts are needed to address the diabetes burden in this First Nation community.

Between a rock and a hard place: Smoking trends in a Manitoba First Nation.

OBJECTIVES: The purpose of this study is to estimate and compare smoking prevalence over two time periods in a Manitoba First Nation community. METHODS: Data fromtwo independent Diabetes Screening Studies in Sandy Bay First Nation, collected in 2002/2003 (n = 482) and 2011/2012 (n = 596),were used. Crude prevalence of current and ever smoking as well as current smoke exposure was estimated. Change over time was tested using a χ² statistic. RESULTS: The crude prevalence of current smoking was 74.0% (95% confidence interval [CI]: 70.1, 78.0) in 2002/2003 and 80.0% (95% CI: 76.8, 83.2) in 2011/2012. The crude prevalence of ever smoking was 83.0% in 2002/2003 and 91.4% in 2011/2012. The prevalence of both current smoking status and ever smoking were significantly higher in 2011/2012 compared to 2002/2003 (p = 0.020 and p < 0.001 respectively). Among participants who were not current smokers, 58.5% (95% CI: 49.6, 67.4) and 76.5% (95% CI: 68.9, 84.1) reported at least one person who smoked in the home in 2002/2003 and 2011/2012 respectively (p = 0.003). In 2011/2012, 96.5% (95% CI: 94.8, 98.2) of those who reported having any children under the age of 18 living in the home were either a current smoker and/or reported that someone else smoked in the home. CONCLUSION: Public health and policy initiatives are needed to address the increase in smoking prevalence in the study community.

Trends in diabetes and cardiometabolic conditions in a Canadian First Nation community, 2002-2003 to 2011-2012.

INTRODUCTION: The burden of diabetes and cardiovascular disease among the Canadian First Nation population is disproportionately high compared with the general Canadian population. Continuous monitoring of the diabetes epidemic among the Canadian First Nations population is necessary to inform public health practice. The purpose of the study was to compare the prevalence of diabetes and cardiometabolic conditions in a Manitoba First Nation between 2 periods. METHODS: Study data were from 2 diabetes screening studies in Sandy Bay Ojibway First Nation in Manitoba, collected in 2002-2003 and 2011-2012. All adults aged 18 years or older were invited to participate in both studies. Crude and sex- and age-standardized prevalence of diabetes and cardiometabolic conditions for each period were estimated and compared with each other by using χ(2) tests. RESULTS: Sex- and age-standardized prevalence of diabetes was estimated at 39.4% (95% confidence interval [CI], 35.1-43.8) in 2002-2003 and was not significantly different (P = .99) in 2011-2012. Sex- and age-standardized obesity prevalence was significantly lower in 2011-2012, at 48.7% (95% CI, 44.6-52.7), compared with 60.8% (95% CI, 56.4-65.2) in 2002-2003 (P < .001). However, this finding was accounted for by a lower prevalence of obesity among men aged 40 to 49 and aged 50 years or older in 2011-2012 compared with 2002-2003. Sex- and age-standardized prevalence of hypertension (P = .97), abdominal obesity (P = .26), dyslipidemia (P = .73), and metabolic syndrome (P = .67) were not significantly different between periods. Significantly higher crude prevalence of obesity, abdominal obesity, dyslipidemia, and metabolic syndrome among women compared with men persisted from 2002-2003 to 2011-2012. CONCLUSION: The diabetes epidemic remains a serious problem in this First Nation community. The gap in cardiometabolic burden between men and women has also persisted.