New analysis of a landmark health survey by the University of Ottawa Heart Institute (UOHI) shows that 70% of Ontario adults are either overweight or obese, and have a strong prevalence of high blood pressure that could lead to heart attack or stroke.

The research, led by Dr. Frans Leenen of the Heart Institute's Hypertension Unit, adds new information to a limited amount of Canadian data on obesity and high blood pressure. The analysis further strengthens the link between high blood pressure and above normal Body Mass Index (BMI), a formula for body composition calculated by height and weight.

"Obesity is rapidly increasing in Canada because we are eating far more than our bodies require. We know better than ever that even being overweight creates other problems such as diabetes and high cholesterol levels and thereby endangers cardiovascular health," said Dr. Leenen.

"Public health strategies to reduce the growing epidemic of obesity would also reduce the burden of high blood pressure and other negative effects leading to heart disease."

Study results were published this week in the American Journal of Hypertension (AM J Hypertens 2010; 23: 1000-1006). They represent the latest analysis from the Ontario Survey on the Prevalence and Control of Hypertension, the first comprehensive assessment of high blood pressure in Canada since 1992.

The survey, conducted by the Heart Institute with the Heart and Stroke Foundation of Ontario, examined 2,552 Ontarians aged 20 to 79 years old in 16 communities from Sudbury to Windsor.

Results showed 52% of people aged 60 and over had high blood pressure but that the majority was receiving treatment. As well, high blood pressure was more common among people from ethnic groups such as South Asians and Blacks.

The latest analysis shows that 48% of adults were overweight (with a BMI of 25 to 29.9) and 22% were obese (with a BMI of 30 and over). Normal BMI falls between 18.5 and 24.9. Obesity levels tended to increase with age from 10% in younger people to 33% in older subjects. High blood pressure was twice as common among obese people. Diabetes and high cholesterol was three fold higher.

"Being obese is followed by several serious heath problems. If we reduce weight, then we can help reduce high blood pressure - these facts are becoming more apparent as a way to live healthier," says Dr. George Fodor, head of UOHI Prevention and Rehabilitation Research, and an investigator who helped lead the research.

Explore further Obesity may hinder optimal control of blood pressure and cholesterol

More information: For more information about calculating BMI, follow this link to Health Canada's interactive tool: For more information about calculating BMI, follow this link to Health Canada's interactive tool: www.hc-sc.gc.ca/fn-an/nutritio … aph_imc_java-eng.php Details of the original study can be found at www.cmaj.ca/cgi/content/full/cmaj;178/11/1441

Provided by University of Ottawa Heart Institute