HealthPop
By

Michelle Castillo /

CBS News/ August 8, 2012, 1:14 PM

Normal-weight Type 2 diabetes patients more likely to die than obese counterparts, study shows

fat, skinny, thin istockphoto
(CBS News) Researchers at Northwestern University have found that normal-weight people who develop Type 2 diabetes have a higher mortality rate than overweight or obese people who develop the disease.

Although weight is one of the factors that puts a person at risk of developing Type 2 diabetes, family history, ethnicity and age may also play a role. Since normal-weight people only account for 5 to 15 percent of new diabetes cases, not much is known about how the disease affects this under-studied group.

"It could be that this is a very unique subset of the population who are at a particularly high risk for mortality and diabetes, and it is possible that genetics is a factor with these individuals," said Mercedes R. Carnethon, associate professor of preventive medicine at Northwestern University Feinberg School of Medicine and first author of the study, said in the press release.

For the study, which was published in the Aug. 7 issue of JAMA, scientists identified 2,625 men and women in the U.S. from five earlier studies who were over the age of 40 and had developed diabetes. The death rate among normal weight diabetes patients was 284.8 per 10,000 person-years, while the death rate for overweight or obese patients was 152.1 per 10,000 person-years.

After adjusting for demographics, blood pressure, waist circumference, smoking status and lipid levels, the researchers found that normal weight individuals were twice as likely to die from diabetes than overweight/obese people. They also found that older adults and non-white participants were more likely to develop normal-weight Type 2 diabetes.

The researchers cautioned that when testing for diabetes, doctors should not ignore Asians, who typically have a lower body weight than non-Asians, and the elderly, since the average onset age of diabetes is between 65 and 75 years old.

"Many times physicians don't expect that normal-weight people have diabetes when it is quite possible that they do and could be at a high risk of mortality, particularly if they are older adults or members of a minority group," Carnethon said in the press release.

One possible explanation as to why that normal weight people are at a higher risk may be due to fitness. Dr. Hermes Florez, director of the division of epidemiology and population health sciences at the University of Miami's Miller School of Medicine, suggested to WebMD that people who don't maintain a healthy lifestyle might be putting themselves at risk for diseases, even if they are at a normal weight.

"It's not just the issue of fatness. It's also the issue of fitness," he told WebMD.

Florez was not involved with the study, but wrote an accompanying editorial, in which he pointed out that 79 million Americans aged 20 or older have prediabetes and nearly 50 million Americans are expected to have the disease by 2050. Currently, there are 25.8 million people or 8.3 percent of the U.S. population living with diabetes, with an estimated 7.0 million people who are unaware they have the disease, the CDC reports.

Carnethon said in a blog post on JAMA that the study doesn't mean that people with diabetes who are normal weight should gain weight or those who are overweight or obese should avoid losing weight.

"We wanted to communicate to physicians in the clinical setting that relying solely on BMI is problematic because people who may not otherwise raise your clinical suspicions may have clinical problems," she explained.

© 2012 CBS Interactive Inc. All Rights Reserved.
8 Comments Add a Comment
linkicon reporticon emailicon
gmanhorse says:
www.fightingdiabetes.net a new but under construction website that will be featuring diabetic news and reports I would appreciate it if you visited
reply
linkicon reporticon emailicon
john92021 says:
I'm not sure which is worse, the trash science or the trash reporting.
Looks like make work all around.
reply
linkicon reporticon emailicon
tmittelstaed says:
The take away is that the study is fundamentally flawed.

A realistic study would be to take 500 thin people who did NOT have diabetes, and 500 fat people who also did NOT have diabetes, then follow them over 40 years or so and see how many of each group died from diabetes.

What you would ubdoubtedly find out is something like 250 fat people got diabetes and 50 died from it, while 100 thin people got diabetes and 75 died from it. Of course, if you kept following the groups you would find that ultimately more fat diabetics would have died from diabetes simply because many more than 2 times the number of thin diabetics would have developed.

the researchers started out with diabetics from both the fat and thin groups, so you already had a flawed study. The reason that researchers publish these types of flawed studies is because they want attention.

Another way of stating this is that due to some genetic factor, 5% of the population who has the propensity of getting diabetes is going to die if they get it, while the rest of the population with the propensity for getting diabetes will NOT die from it if they get it. This "going to die" population is evenly distributed among fat and thin people. The reason the numbers of this study look better for fat diabetics is that among thin people as a whole, fewer people get diabetes and the ones that do are from that 5%, while among the fatties, the additional diabetics drawn from the "not-going-to-die" population overshadows the 5% So by starting the study out with diabetics from each group, you have already selected the answer you wanted - the stupid one - and now you can get more money for doing more stupid studies.
reply
EmpireGeorge______-- replies:
linkicon reporticon emailicon
Great points, because the obesity alone can "cause" type 2 diabetes.....so it's flawed to test those who are fat, who already had it.
linkicon reporticon emailicon
Ulgnud says:
It would be nice if the medical community would collectively make up it's mind.
reply
linkicon reporticon emailicon
foo8259 says:
Funny they never mentioned DIET -- one of the most important factors leading to type II or pre-diabetes. A low-cab diet instead of a low-fat high-carb diet is key, even for type I diabetics.
reply
linkicon reporticon emailicon
mcgroober says:
Was this study funded by the fast food industry?
reply
linkicon reporticon emailicon
czlc89 says:
As stated, normal weight people only account for a small percentage of diabetes, which might skew the data. Can't jump to the conclusion that being overweight with diabetes its healthier than being normal weight. Regardless, I think the take home point should be to get regular testing and control your sugar intake. That way, you can prevent diabetes and its complications and avoid side effects from diabetes meds.
http://www.publichealthwatchdog.com/louisiana-man-says-diabetes-drug-actos-caused-bladder-cancer-files-lawsuit/
reply