Study suggests type 2 diabetes rates are dropping
Prevention strategies could be contributing to a recent fall in the number of people developing type 2 diabetes in some high income countries, suggests a review of evidence which has just been published.
The findings show that after 2005 many populations 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 activities.
However, they have also warned there is limited evidence from low and middle income countries, where trends in diabetes incidence might be different.
Monitoring of the global diabetes epidemic has mainly focused on diabetes prevalence which continues to rise. However, this is partly driven by improved treatment and better survival.
In contrast, studies on diabetes incidence are scarce. Among those that do exist, some report a fall or stabilisation of new cases, but results remain inconsistent.
A research team, led by Dianna Magliano at the Baker Heart and Diabetes Institute in Australia, 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 in mostly high income countries over five different time periods from 1970-2014.
After taking account of differences in study design and quality, the researchers show 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.
If these trends continue, it may mean that incidence is starting to stabilise and this could indicate that prevention and public health activities may have had an effect
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.
The authors said: “The rate of new cases of diabetes, mainly type 2 diabetes, continued to rise among people aged 35 years and above over the last four decades, with the highest rate observed in studies beginning around 2000-04. Studies that began in 2010 and later suggested a possible downturn in incidence. Further investigations are required to establish the trends in different region/ethnic subgroups.
“If these trends continue, it may mean that incidence is starting to stabilise and this could indicate that prevention and public health activities may have had an effect. Lower levels of screening for diabetes may have played a role, and it is also possible that depletion of susceptible people may be involved. In reality, it is probably a combination of all these factors.”
Responding to the research, Dr Emily Burns is Head of Research Communications at Diabetes UK, said: “This study looks at type 2 diabetes through a different lens, reporting on the number diagnosed rather than the number living with the condition – which can often be distorted by factors such as how long people live for.
“With this in mind, it’s promising to see that the number of people being diagnosed with type 2 diabetes might potentially be plateauing in certain parts of the world. However, it’s important to highlight that this study wasn’t able to represent everyone living with type 2 diabetes, so more diverse research is needed before we can fully understand any changing trends.
“The challenges posed by obesity and unhealthy lifestyles – the two main drivers for type 2 diabetes – remain significant, with more people being at risk of developing the condition than ever before. That’s why, while the findings are interesting, this study doesn’t detract from the seriousness of the growing diabetes crisis and the vital prevention efforts underway to help tackle this.”
To read the study in full, click here.