High blood pressure on the rise in teens

The rising rate of obesity among kids and teens is now leading to other health problems in that age group, including diabetes, high blood pressure and vascular damage.

Chronic high blood pressure can affect the heart and can cause the pumping chamber (the left ventricle) to become enlarged. Developing high blood pressure at an early age can lead to cardiovascular problems later in life.

“High blood pressure is no longer an adult-only disease,” says Sarah Couch, PhD, associate professor of nutritional sciences in the UC College of Allied Health Sciences. “Early prevention and intervention efforts are needed to address this increasing public and individual health problem.”

Couch, who studies how diet affects health, was recently awarded funding from the National Heart, Lung, and Blood Institute to examine the long-term effects of a specific diet on blood pressure and vascular function in adolescents.

The funding, $1.9 million over five years, will support the study of 185 adolescents who will be seen in the Hypertension Clinic at Cincinnati Children’s Hospital Medical Center. Couch and colleagues will investigate how well a diet low in fat and sodium lowers blood pressure.

Couch’s team will compare regular hospital-based nutritional care to the DASH diet, which stands for dietary approaches to stop hypertension and is particularly high in fruits and vegetables and low in fat and sodium.

“We’ve studied the DASH diet in the past and have demonstrated its short-term effects on lowering blood pressure in adolescents,” says Couch. “We’re now trying to determine whether the diet works long-term to improve blood pressure.”

Study participants will be randomly assigned to receive the DASH diet intervention or regular nutrition care. They will be asked to stick with either diet for a 24-week period. Blood pressure will be measured two weeks before beginning the study and again upon completion. Participants will also be asked to come in for a one-year follow-up appointment.

Couch’s team will use in-person counseling sessions and follow-up telephone calls to assist with and determine adherence to each diet. Parental involvement in this study, Couch says, is crucial.

“Parents are ultimately the ones responsible for buying the groceries, so their participation in their child’s health is extremely important.”

Blood pressure (hypertension) is calculated by measuring the “systolic” number, which represents the pressure inside arteries when the heart is beating, and the “diastolic” number, the pressure in arteries when the heart is at rest.

These numbers are organised by placing the systolic reading on top of the diastolic reading. In adults, a blood pressure measurement of 120/80 is considered normal. A reading between 121–139/80–89 is considered pre-hypertensive, and a reading higher than 140/90 indicates high blood pressure.

In adolescents, blood pressure is measured the same way, although age, gender and height are considered when deciding what level is appropriate.

Couch says one high reading in adolescents should result in a referral to a hypertension clinic, where the child can be monitored to determine if their blood pressure is in fact elevated.

(Source: University of Cincinnati: April 2008)