The Falling Rates of Diabetes May Be Misleading
In December 2015, the CDC reported that diabetes was on the decline. In 2009, there were more than 1.7 million new cases diagnosed, but between 2009 and 2014 the number of newly diagnosed dropped, totaling just 1.4 million over 5 years.
According to the CDC report, new surveillance data indicates the US population is moving in the right direction, based on factors attributed to increased physical exercise and better food choices.
Statistics show that between 1980 to 2014 diabetes diagnosis nearly doubled for adults ages 65-79. Among adults 45 to 65 years old, an increase was found from 1992 to 2002, but leveled off between 2002 and 2014. Among adults 18-44 years, a significant increase was seen from 1980-2003, and little change from 2003-2006, but a significant reduction between 2006 to 2014. These numbers represent type 2 diabetes, and while the news is good, it does not represent the type 1 community, at all.
The CDC report used numbers from the National Health Interview survey, which asked respondents if they had ever been told they have diabetes, by a healthcare professional, but the survey didn’t ask participants what type of diabetes they had.
The fact is that type 1 is on the rise. In 2006, WHO reviewed the statistics from 57 countries and 112 diabetes research centers and found that type 1 had risen an average of 5.3% in North America, 4% in Asia and 3.2 % in Europe. More recent data, from the SEARCH for Diabetes in youth study, showed a 21% increase in the number of new cases of type 1 diabetes between 2001 and 2009. While globally the numbers of kids with type 1 diabetes has risen 9% since 2013 - statistics provided by International Diabetes Federation.
Type 1 and type 2 share the same underlying defect – the inability to supply enough insulin to keep blood sugar within a normal range – but both types of diabetes arise out of opposite processes.
Type 1 is an autoimmune disease, in which the body attacks it’s own beta cells that produce insulin. The effect destroys the body’s ability to make insulin. With type 2 diabetes, tissues that need insulin to take up glucose become resistant to insulin’s presence. The beta cells respond by going into overdrive, even though the body isn’t responding. In some people with type 2, the overdrive brings on a total shut down of the beta cells and they stop making insulin. In simpler terms, a person cannot sustain life with 10% of their beta cells (type 1), but a person with 50% of greater can sustain life with diabetes (type 2).
Autoimmune diseases are on the increase, but the reasons are not exactly clear. In the case of type 1, there are many theories as to what causes the autoimmune system to go awry - and specifically - to cause type 1 diabetes.
Since type 1 is on the rise globally, investigators are sifting through possible causes globally, but also believe that local factors may be more important in some regions.
The list of culprits to the increase in type 1 is extensive and complex, but here are a few that researchers are putting some weight behind.
The Hygiene Hypothesis
Researchers are giving more attention to bacteria, viruses and parasites as a potential cause for type 1 diabetes. The hygiene hypothesis proposes that the early exposure to infections, or soil organisms, teaches the developing immune system how to maintain itself and keeps it from reacting in an uncontrolled way. Best example of what I mean is allergens – like ragweed and dust. If there is more exposure to them at a young age, there might be less of a change that they will kick off an outrageous response.
The way researchers look at type 1 and the hygiene hypothesis, they speculate that the immune system learns not to overreact, while also learning to tolerate the body’s cellular metabolism and prevent an autoimmune attack that destroys the ability to make insulin. (I wrote this article about one of the most recent research projects on type 1 and this theory.)
The Accelerator, or Overload Hypothesis
This is fairly new, but this theory looks at the role of fat in the body. Just as people are starting to realize the differences between type 1 and type 2, here comes a theory that throws mud into the water for how to differentiate the two forms of diabetes.
The Accelerator Hypothesis ties fat into part of the cause for the depletion of beta cells. This theory may make many in the type 1 community mad, as they often differentiate themselves by saying “ours is not connected to weight, or what you eat.” The accelerator theory ties three processes together, constitution, insulin resistance and autoimmunity. In children who are chubby, their weight challenges the load the beta cells can do. It leads to insulin resistance and later, the children encounter an autoimmune attack that becomes type 1 diabetes. This is largely associated with industrialized countries, where lifestyles tend to be more sedentary.
The complexity of the human body is a marvel. For people with diabetes, our body is God’s creation with the devil’s fingerprint. But steady work by the brilliant minds that make up our research world continue to make us more informed and better able to stay healthy. Patience is everything, and the research news exciting.
To add some other areas for clues as to what are other culprits, take a look at the links below:
_Scientific America, February 2012 – Diabetes Mystery: Why Are Type 1 Cases Surging _
_Medscape, 2002 - The Rise of Childhood Type 1 Diabetes in the 20th Century _
_Diabetologia, January 2016 - Enterovirus infection is Associated with Increased Risk of Type 1 Diabetes _
_Pacific Standard, May 2014 – Why is Type 1 Diabetes Rising Among America’s Youth? _
NPR, January 2016: Diabetes Types Can Be Confusing
Ann wrote for HealthCentral as a patient expert for Diabetes.