The number of acute ischemic stroke hospitalizations doubled in a thirteen year period amongst males aged 15 to 34. The rate increased 17 % in females between 15 and 34. This research, presented at the ongoing American Stroke Association’s International Stroke Conference in Dallas this week, also stated that although this is a dramatic increase, a dip of half of incidence was reported in women zero to four and a 25% drop in men over 45 years. Women saw a decline of almost 30% in strokes for those over 45 years old as well. What has caused this dramatic change? Researchers are unclear on the reasons for the increase, but said obesity and hypertension may be factors.

Xin Tong, M.P.H., a health statistician with the CDC’s Division for Heart Disease and Stroke Prevention in Atlanta stated:

“I believe this is the first large study to report these findings, stratified by age and gender. We cannot link anything in particular to the trend in younger patients, but I believe the role of obesity and hypertension will prompt a big discussion. Unfortunately, right now we can’t speculate on the causes.”

Obesity is the result of caloric imbalance (too few calories expended for the amount of calories consumed) and is mediated by genetic, behavioral, and environmental factors. Childhood obesity has more than tripled in the past 30 years. The prevalence of obesity among children aged 6 to 11 years increased from 6.5% in 1980 to 19.6% in 2008. The prevalence of obesity among adolescents aged 12 to 19 years increased from 5.0% to 18.1%.

Obese youth are more likely to have risk factors for cardiovascular disease, such as high cholesterol or high blood pressure. In a population based sample of 5 to 17 year olds, 70% of obese youth had at least one risk factor for cardiovascular disease.

Children and adolescents who are obese are at greater risk for bone and joint problems, sleep apnea, and social and psychological problems such as stigmatization and poor self-esteem. Obese youth are more likely than youth of normal weight to become overweight or obese adults, and therefore more at risk for associated adult health problems, including heart disease, type 2 diabetes, stroke, several types of cancer, and osteoarthritis.

The unit of analysis in this study was hospitalization, so researchers couldn’t draw any firm connections or determine what factors are driving the increase in ischemic stroke cases among the young. Ischemic stroke occurs when blood supply to the brain becomes obstructed, usually by a clot or narrowing of the arteries.

Tong continues:

“Acute ischemic stroke is currently considered something that mostly happens to older people, but awareness of rising rates in the young is important or else tPA and other important stroke treatment may be unnecessarily delayed in younger patients.”

The classic role of tPA is in the clotting system. To be specific, tPA catalyzes the conversion of plasminogen into plasmin. It does so by cleaving the single-chain plasminogen into two chains. Because it works on the clotting system, tPA is used in clinical medicine to treat only embolic or thrombotic stroke. Use is contraindicated in hemorrhagic stroke and head trauma.

Stay up to date on the latest news from American Heart Association scientific meetings, including the International Stroke Conference 2011, by following at www.twitter.com/heartnews, using hashtag #ASA11News.

Source: American Heart Association

Written by Sy Kraft, B.A.