First Nations Women of Canada Have Higher Diabetes Rates, Study Finds

Data collected between 1995 and 2014 show that the prevalence and incidence of diabetes are substantially higher in First Nations people in Canada compared with those who live in Ontario, according to a study published in the Canadian Medical Association Journal.

Specifically, there was a greater prevalence of diabetes in First Nations women aged 20 to 43 years compared with women in that age group (4.2% vs 1.6%) who lived in Ontario. In addition, the rate of diabetes among First Nations women aged 35 to 49 years was 17.6% compared with 6% of the Ontarian general population. The study also found diabetes occurs at younger ages among First Nations people.

Because children born to mothers with diabetes are more likely to have type 2 diabetes, adiposity, and lipid abnormalities, these findings are particularly important. Higher prevalence of the disease in women of reproductive age could lead to potential generational impacts on metabolic health, the authors warn.

They analyzed health services population data from Ontario and linked it to the federal Indian Register to determine age- and sex- adjusted annual estimates of diabetes prevalence, using a 95% confidence interval. They also looked into where populations resided and whether this had an impact on prevalence. Records of 158,241 First Nations people and more than 13.2 million other Ontarians were included in the study. The data collected did not specify between type 1 and type 2 diabetes, nor did it include cases of gestational diabetes.

Previous research shows that diabetes is 3 times more likely in First Nations people compared with the general population. Now that gap has narrowed to twice as high.

“While these findings represent promising progress, and may indicate real declines in the risk of diabetes, the declines in incidence do not track with declining prevalence of diabetes risk factors and may be an artifact of changing diagnostic criteria or screening practices," said Jennifer Walker, PhD, an author of the paper.

The study also found the lifetime risk of diabetes was higher among First Nations people compared with other people in Ontario, at 57% versus 44.5%.

In 1995, the adjusted prevalence of diabetes for First Nations people was 11.1%, while in 2014, it was 16.6%. Researchers also found the highest prevalence rates among those living in First Nations communities.

These findings can be partially attributed to “a complex set of physical and social factors…including the intergenerational impacts of ongoing colonial policy and resultant social, political, economic, and cultural inequities” experienced by First Nations people, the researchers said.

Although diabetes mortality rates for both populations decreased throughout the study period, “they remained higher for First Nations people, particularly since 2001,” the authors note. The all-cause mortality rate among First Nations people with diabetes was 33.32 per 1000 people in 2014 compared with 25.43 per 1000 among the Ontario general population.

The authors believe these findings contribute to the fact that avoidable mortality is significantly higher among First Nations people compared with the rest of the Canadian population.

To help address this health crisis, the researchers determined “complex interactions among land, culture, environment, community, and colonial disruption” should be taken into account. “Risks of diabetes are best understood using a framework based on indigenous determinants of health.”

Reference

Walker JD, Slater M, Jones CR, et al. Diabetes prevalence, incidence and mortality in First Nations and other people in Ontario, 1995-2014: a population-based study using linked administrative data. Can Med Assoc J. 2020;192(6):E128-E135. doi: 10.1503/cmaj.190836.