MRI and magnetic resonance may help predict which people
at risk for type 2 diabetes will benefit from lifestyle changes, new data
“Abdominal and liver fat are the two most important
factors in predicting whether a lifestyle intervention will be
successful,” Jürgen Machann, PhD, of University Hospital
Tubingen, Germany, said in a press release.
Machann and researchers performed MRI and magnetic
resonance spectroscopy on 243 individuals before and 9 months after a lifestyle
intervention. The intervention called for a weight loss of 5%, fat intake
reduction to a maximum of 30% of total calories and moderate physical activity
at least 3 hours per week.
Each of the participants, which included 144 women and
99 men, was considered at risk for developing type 2 diabetes as a result of
obesity (BMI of 27 or greater), impaired glucose tolerance or having a
first-degree relative with diabetes.
At baseline, men had about two times the amount of
visceral adipose tissue and a smaller amount of adipose tissue (25.9%) compared
with women (36.9%). In addition, the baseline insulin sensitivity of men was
significantly lower than the sensitivity of women.
The researchers used improved insulin sensitivity to
measure the success of the lifestyle intervention. After 9 months, insulin
sensitivity improved in 71% of the men and 58% of the women. Individuals with
improved insulin sensitivity lost significant amounts of visceral fat (19% for
women; 20% for men) and liver fat (35% for women; 44% for men) as well as lost
3% to 5% of body weight.
“The participants who improved their health status
as a result of diet and exercise started out with lower baseline levels of
abdominal and liver fat,” Machann said.
Individuals who did not improve insulin sensitivity
after 9 months of lifestyle intervention lost smaller amounts of visceral fat
(4% for women; 6% for men). Men also lost less liver fat (15%), and women
gained about 22% of liver fat.
For men, low baseline concentrations of visceral adipose
tissue, hepatic lipids and abdominal subcutaneous fat were predictors of
successful lifestyle intervention; however, for women, low hepatic lipid levels
were the only predictor of success.
“Our results demonstrate that with MRI and magnetic
resonance spectroscopy, we can determine who will benefit from dietary changes
and exercise and who will need other interventions,” Machann said.