A seven-year ongoing study examining over 20,000 Canadian grade 9 students shows most already have at least one major risk factor for heart disease and stroke, Dr. Brian McCrindle told the Canadian Cardiovascular Congress 2009, co-hosted by the Heart and Stroke Foundation and the Canadian Cardiovascular Society.
"This study is further evidence of an accelerating decline in the heart health of Canada's teens," says Dr. McCrindle, a cardiologist at The Hospital for Sick Children in Toronto. "Children shouldn't have these profiles."
The study investigated the heart health of 20,719 grade 9 students aged 14 and 15 years.
The study found that, between 2002 and 2008, the rates of high blood pressure, high cholesterol, and obesity in these teens were alarmingly high and, even more worrisome, increasing over time.
Risk factors of Canadian 14 and 15 year olds ------------------------------------------------------------------------- Grade 9 students with 2002 2008 Increase from 2002 to 2008 ------------------------------------------------------------------------- One or more cardiovascular risk factors 17% 21% +4% ------------------------------------------------------------------------- High blood pressure 19% 17% -2% ------------------------------------------------------------------------- Elevated cholesterol levels 9% 16% +7% ------------------------------------------------------------------------- Obesity 11% 13% +2% -------------------------------------------------------------------------
"It is shocking that one in five 14 and 15 year olds has high blood pressure," says Heart and Stroke Foundation spokesperson Dr. Beth Abramson. "What does this say for the future health of these young teens? They are at risk of developing long-term health effects such as premature heart disease and type 2 diabetes."
High blood pressure is the leading cause of stroke and a major risk factor for heart disease. "We're ringing the alarm bell. Every child has the right to grow up healthy," says Dr. Abramson.
The teens' elevated cholesterol rates had the greatest increase, accelerating from nine to 16 per cent in six years. "An increase of this magnitude in this age group is astonishing," says Dr. Abramson. "These risk factor levels will continue to increase and track into adulthood unless we do something now. These children are in grave danger."
Dr. McCrindle says the situation could be even worse than it looks. There is a synergistic relationship between risk factors.
"One of the things we already know is that it is the number of risk factors you have that really accelerates the whole process," he says. "And when you have a healthy looking kid in front of you, it's easy to miss the invisible time bomb waiting do go off."
Lifestyle factors of Canadian 14 and 15 year olds ------------------------------------------------------------------------- Grade 9 students' levels of 2002 2008 Change from 2002-2008 ------------------------------------------------------------------------- Physical activity 28% 22% -6% (Physically active for 90 minutes at least five days a week) ------------------------------------------------------------------------- Sedentary behaviour 22% 24% +2% (20 or more hours per week of TV or video games) -------------------------------------------------------------------------
"Unfortunately, our kids' gaming superheroes are getting better workouts than they are," says Dr. Abramson.
"With changing technologies, we need to exercise our bodies more than our brains," she says. "Over 50 per cent of Canadian children between the ages of five and 17 aren't active enough to support optimal health and development - and over a quarter of our children and youth are overweight or obese."
They don't do any better on the nutrition front: only half get the daily recommended amount of fruit and vegetables.
Healthy behaviours including regular physical activity that begin at a young age and continue throughout life are important to achieving and maintaining a healthy weight. Dr. Abramson recommends that children and youth build up to at least 60 to 90 minutes of daily physical activity most days of the week and consume a healthy, balanced diet that includes foods from the four food groups in Canada's Food Guide.
"You don't have to try to fit something else into their busy days," she says. "You simply need to encourage children to trade an hour of inactivity for an hour of activity."
Dr. McCrindle notes that family history, low levels of physical activity, high levels of sedentary behaviour, poor nutrition, and lower socio-economic status all play a role.
He says that one of the great deficiencies in Canada is that, although there is a push to recognize guidelines for management of risk factors in adults, there is very little for kids.
"We need comprehensive and integrated Canadian guidelines for keeping our children healthy and we need them soon because this type of study is showing the worst is yet to come," says Dr. McCrindle. "This is the first generation of children that may have a shorter lifespan than their parents."
The data were collected by Heart Niagara Inc., a nonprofit corporation which partnered with school boards and public health officials in a grade 9 physical education curriculum enrichment program designed to prevent chronic disease.
They assessed students' blood pressure, height and weight, and blood cholesterol, capturing pretty well all of the grade 9 students in the system.
"It took a collaborative effort to collect this data. Working together is key to turning around the heart health of our children," says Dr. Abramson. "It takes a village to raise a child and it will take all levels of society to give our children a healthier future. Individuals, families, schools, communities, businesses, industry, and government collectively can play a role in improving the health of our youth - now and for the future."