High blood pressure (hypertension) causes more than 1 million premature deaths in China, and over 2 million total deaths, making it the leading preventable cause of death in the country. The Chinese government must make prevention and control of hypertension its top public health priority. Primary prevention, including reducing the enormous average daily salt intake and lifestyle modification, will be a vital tool in such efforts. These are the conclusions of an Article published Online First and in an upcoming edition of The Lancet, Prof Jiang He, Tulane University School of Public Health and Tropical Medicine, New Orleans, LA, USA, and colleagues.

An estimated 972 million adults, or 26•4% of the world's adult population, had hypertension in 2000. The number of adults with hypertension in 2025 is predicted to increase by 60% to 1•56 billion. This number, however, does not include prehypertension (slightly raised blood pressure that does not qualify as 'full' hypertension). In this study, the authors estimated premature deaths attributable to increased blood pressure in China. A nationally representative sample of around 170,000 Chinese adults aged 40 years and older was studied. Blood pressure and other risk factors were measured at a baseline examination in 1991 and follow-up assessment was done in 1999 - 2000. Premature death was defined as mortality before age 72 years in men and 75 years in women, which were the average life expectancies in China in 2005.

Hypertension and prehypertension were significantly associated with increased all-cause and cardiovascular mortality. In 2005, an estimated 2•3 million cardiovascular deaths were attributable to increased blood pressure in China: 2•1 million in adults with hypertension and 0•2 million in adults with prehypertension. Additionally, 1•3 million premature cardiovascular deaths were attributable to raised blood pressure in China: 1•2 million in adults with hypertension and 0•1 million in adults with prehypertension. Most blood pressure-related deaths were caused by cerebrovascular diseases: (1•9 million total deaths and 1•1 million premature deaths).

The authors say: "Our results show that raised blood pressure is the leading preventable risk factor for premature deaths in China... The enormous mortality burden related to blood pressure that we have documented is striking and unexpected compared with previous estimates."

They highlight that the prevalence of hypertension is high and increasing in the Chinese population, whereas the proportion of awareness, treatment, and control is low. A previous national survey suggested that roughly 153 million Chinese adults aged 18 years or older met criteria for diagnosis of hypertension, of whom only 24% were aware of their condition and 19% were receiving antihypertensive drugs. Worryingly, adequate control of blood pressure (