Obesity, Diabetes Damage Young Arteries
Teenagers and young adults who are obese or have type 2 diabetes show signs of artery damage that may increase their risk of heart attack and stroke later in life, according to a study in Circulation: Journal of the American Heart Association.
“Because this damage is progressive and has started so early, this may be the first generation that has a shorter life expectancy than their parents,” said Elaine Urbina, M.D., lead study author and director of preventive cardiology at Cincinnati Children’s Hospital Medical Center Heart Institute. Using non-invasive ultrasound imaging, researchers found that fatty plaque build-up in the arteries leading to the head (carotid arteries) was thicker in young people with type 2 diabetes and those who were obese compared to those who were lean. Stiffness of the carotid artery was also greater among those with diabetes or obesity compared to lean youth.
“It’s scary that the arterial stiffness is just as bad in the obese youth as in those with type 2 diabetes,” Urbina said. “This functional damage may be occurring quite early in the disease process, and we hope to find out more by following these kids over time.”
In adults, a greater carotid intima media thickness (cIMT) is linked with a risk of future stroke and is an indicator that plaque is building up in arteries throughout the body, including the coronary arteries feeding the heart muscle. Carotid stiffness, one manifestation of hardening of the arteries, occurs when the vessels aren’t flexible enough to expand to accommodate increased blood flow.
Adolescents and young people are becoming obese and developing type 2 diabetes at an alarming rate — so much so that the condition is no longer called adult-onset diabetes, said Urbina, who is also an associate professor at the University of Cincinnati.
Prior to this study, limited information existed on whether children with risk factors for heart disease begin developing plaque build-up and hardening of the arteries. The study was unique because it found vascular damage in a large population of youth. This damage should alert health care practitioners to address cardiovascular risk factors early to prevent an increase in stroke and heart attack as these children age.
The study group included 128 youth (average age 19) diagnosed with type 2 diabetes; 136 obese youth (average age 18), with weight-for-height above the 95th percentile on pediatric growth charts; and 182 matched lean youth (average age 18), with weight-for-height below the 85th percentile. Obese controls were given a glucose tolerance test to make sure they didn’t have undiagnosed type 2 diabetes.
Participants with obesity or type 2 diabetes were more likely to have several traditional heart disease risk factors, including higher blood pressure, triglycerides, total cholesterol and “bad cholesterol” (low-density lipoprotein or LDL-cholesterol). However, these differences could only partially account for the significant changes in artery structure and function, researchers said.
“Our objective is to identify youths who will need more aggressive therapy,” Urbina said. “Some kids need to go right onto medication, while others can be treated with lifestyle changes.”
There’s not enough information on the normal range of carotid measurements in children to offer the tests outside of research studies. However, children who are obese or have type 2 diabetes should have a thorough assessment of traditional heart disease risk factors and be treated accordingly, Urbina said.
“Comprehensive lifestyle intervention to reduce obesity must be applied now if we are to prevent a projected decline in life expectancy of our youth,” she said.
“Studies, such as Dr. Urbina’s, reinforce the need to provide comprehensive health benefits for children for the prevention, assessment and treatment of childhood obesity,” said Ginny Ehrlich, Executive Director of the Alliance for a Healthier Generation, a joint initiative of the American Heart Association and the William J. Clinton Foundation to combat childhood obesity. “We know that effective prevention and the reversal of obesity will lead to longer and healthier lives. The Alliance Healthcare Initiative makes it possible.”