Many patients worldwide don\'t know they have hypertension, and even if they do, too few receive adequate medication, Australian and Canadian researchers say. Lead author Dr. Clara Chow of Sydney University and the George Institute for Global Health in Australia, and senior author Dr. Salim Yusuf, a professor of medicine of McMaster University\'s Michael G. DeGroote School of Medicine, in Canada, said the findings were true in high income countries, as well as middle and low income countries. Yusuf said drug treatments to control hypertension are well known, but this study found only about a third of patients who are aware of their condition were achieving target blood pressure control. \"Blood pressure lowering drugs are generally inexpensive and commonly available treatments,\" Yusuf said in a statement. \"However, only a third of patients commenced on treatment are on enough treatment to control their blood pressure. This is worst in low income countries, but significant in high and middle income countries too.\" Hypertension or high blood pressure is the leading cause of cardiovascular disease, which is associated with at least 7.6 million deaths per year worldwide. Participants in the Prospective Urban Rural Epidemiological study included 154,000 adults ages 35-70, with and without a history of heart disease or stroke, from 17 high, middle and low-income countries. Each study participant had their blood pressure measured and medication use recorded, along with information about their age, gender, education and key risk factors. The study, published in the journal of the American Medical Association, found 46.5 percent of those with hypertension were aware of the diagnosis, while blood pressure was controlled among 32.5 percent of those being treated.