China Death Toll Due to Hypertension Worse Than Predicted

October 06, 2009

October 6, 2009 (New Orleans, Louisiana) — High blood pressure is the leading preventable risk factor for premature death in China, a new prospective cohort study shows [1]. The figures, which estimate that almost 2.5 million deaths there were attributable to hypertension in 2005, are "striking and unexpected compared with previous estimates," say Dr Jiang He (Tulane University, New Orleans, LA) and colleagues in a study published online October 6, 2009 in the Lancet.

He told heartwire : "We were surprised by the findings because the number of deaths due to hypertension was higher than we thought. We have documented hypertension as the number-one killer in China."

This study is the first in the world to use real data and to really document in China how many people die from . . . hypertension.

In an accompanying comment [2], Drs Stephen MacMahon (George Institute, Sydney, Australia) and Lijing Yan (George Institute China, Beijing) say, "The toll conferred by raised blood pressure [in China] represents a health crisis by any definition, [but] such news is in fact old. The real news is that, despite long recognition of the global burden of blood pressure and the wide availability of cheap effective interventions, most major international health organizations continue to pay only lip service to this preventable epidemic."

He disagrees, however, telling heartwire : "This is not old news. This study is the first in the world to use real data and to really document in China how many people die from [the consequences of] hypertension. Other studies have calculated and made assumptions."

Most Chinese Deaths Due to Hypertension Caused by Stroke

He and colleagues studied a nationally representative sample of around 170 000 Chinese adults aged 40 years and older, in whom blood pressure (BP) and other risk factors were measured at a baseline examination in 1991. Follow-up assessment was done almost 10 years later, in 1999–2000.

They recorded all deaths and premature deaths--defined as mortality before age 72 years in men and 75 years in women, which were the average life expectancies in China in 2005--and found that hypertension and prehypertension were significantly associated with increased all-cause and cardiovascular mortality. They then modeled the numbers of total and premature deaths attributable to BP in China as a whole, using population-attributable risk, mortality, and the population of China in 2005.

They found that 2.3 million cardiovascular deaths were attributable to increased blood pressure: 2.1 million in adults with hypertension and 0.2 million in adults with prehypertension. In addition, 1.3 million premature cardiovascular deaths were attributable to hypertension there. Most blood-pressure–related mortality was caused by cerebrovascular diseases: 1.9 million total deaths and 1.1 million premature deaths.

Education Is Key: Too Much Salt Causes Strokes

He said one of the most important issues now is prevention, promoting the deleterious effects of high blood pressure to the people of China: "For example, we need to educate Chinese people that a high sodium diet will increase their blood pressure and increase their risk of stroke." This will require a different tactic to that employed in Western countries, he said, because Chinese people, especially in rural areas, do not tend to get their excess salt from prepackaged foods; rather, they use soy sauce and in addition add salt to their own cooking. Replacement of regular sodium salt with reduced-sodium (potassium) salt "will enable us to reduce a lot of BP-related disease," he told heartwire .

He said the prevalence of hypertension in China is similar to that in many other countries, but the rate of treatment and control there "is much lower" than in other places, necessitating a number of key goals. "We need to make BP measurement routine, promote screening for BP in the community, and stress the importance of regular BP measurement." People in the community can be trained to measure blood pressure, and nurses and other people in the community can also be employed in other aspects of hypertension control. Key to tackling this problem is ensuring the availability of antihypertensive medication and stressing the importance of compliance with medication, he notes.

MacMahon and Yan explain that most healthcare resources in China are highly concentrated in urban areas in the east and south of China, "and the resources available to the enormous populations in the rural west and center are more limited." In addition, per capita, China's expenditure on healthcare is roughly a tenth of that in the UK or Australia, and the number of medical practitioners is roughly 40% of that in developed countries. "The challenge is to formulate, evaluate, and implement new solutions that are affordable and acceptable to the rural poor and that do not depend on delivery by medical practitioners," they note.

Chinese Government Initiative and Other Projects Planned

He describes a new initiative by the Chinese government, called the Rural Healthcare Plan, which is trying to improve this situation. "The government will provide most of the funding, with some small contributions from the public, so that "everyone will have healthcare coverage," he explained.

Part of this plan will be the temporary assignment of doctors to the countryside, for at least a few years, he says. "Just as in Western culture, a lot of physicians don't like to practice in rural areas, but this new initiative involves a big effort to encourage young medical graduates to work in rural areas for at least a few years."

MacMahon and Ling describe their involvement with another project, the China Rural Health Initiative, funded by the US National Heart, Lung and Blood Institute (NHLBI) and the UnitedHealth Group.

This will establish a large network of rural healthcare centers that will conduct a number of controlled studies of pragmatic primary-care interventions. "The first priority for the initiative is the development and evaluation of a low-cost intervention package for the prevention of blood-pressure-related diseases in high-risk individuals," they explain. Designed for delivery by village healthcare workers, the package includes a targeted screening program, a simple electronic decision-support tool, a treatment algorithm with low-cost antihypertensive drugs (designed to reduce stroke risk by around half), and a follow-up program to maximize adherence.

"In addition to these clinical components, other factors that will be evaluated include financial and nonfinancial incentives for healthcare workers and the provision of free or subsidized drug therapy to patients," note MacMahon and Yan.

"Hopefully, this and other similar research initiatives . . . will go some way toward redressing the neglect accorded this health crisis in previous decades," they conclude.

The George Institute is the recipient of research grants from the US NHLBI and the UnitedHealth Group.