Are rates of type 2 diabetes falling?
Tuesday, 17 September 2019
Prevention strategies could be contributing to a fall in the number of people developing type 2 diabetes in some high income countries, suggests a study published by the Baker Heart and Diabetes Institute.
The study shows that since 2005 some populations have started to see a decline in the number of people developing diabetes, prompting the researchers to suggest that we may be starting to beneﬁt from type 2 diabetes prevention strategies.
But they warn that in low and middle income countries, the trends for diabetes continue to rise.
To date monitoring the global diabetes epidemic has focused on the number of people living with the condition, which continues to rise. However, this is partly driven by improved treatment and better survival.< In contrast, studies on diabetes incidence (number of newly diagnosed cases) are scarce. Among those that do exist, some report a fall or stabilization of new cases, but results remain inconsistent.
This is why a research team led by Dianna Magliano at the Baker Heart and Diabetes Institute set out to review the evidence on diabetes incidence trends over time.
Their findings are based on published data on the incidence of type 2 diabetes in more than 100 populations over five different time periods from 1970-2014. The researchers show that the number of people developing diabetes increased consistently until 2005 (with a peak between 1990 and 1999) but the number of new cases has been generally stable or falling since then.
For example, from 1990 to 2005, diabetes incidence increased in two-thirds (67%) of populations, was stable in 31% and decreased in 2%. But from 2006 to 2014, increasing trends were reported in only a third (33%) of populations, whereas 30% and 36% had stable or declining incidence, respectively.
Countries that showed recent stable or decreasing trends were mainly from Europe and East Asia. However, the researchers say they lacked data from many low and middle income countries, where large increases in the incidence of diabetes could still be occurring.
They also outline some limitations of their review, such as being unable to analyze different sex and age groups separately, and variations in diagnostic criteria for diabetes. Nevertheless their results were largely unchanged after further analysis, suggesting that the findings withstand scrutiny.
As a result they have suggested that preventive strategies and public health education and awareness campaigns “may have contributed to this flattening of rates, suggesting that worldwide efforts to curb the diabetes epidemic over the past decade might have been effective.”
However, many global researcher say we need to be cautiously optimistic, noting that falling or stalling rates “can be deceptive” and that social and financial factors will influence new people being diagnosed with diabetes.
So while the study indicates we have reason to be optimistic that diabetes is in retreat in some populations, it does not provide definitive evidence that true incidence is actually falling globally.