Reducing High Blood Pressure : Health: Group seeks backing of government and industry in preventing and treating hypertension. It afflicts twice as many blacks as whites.

Almost every black family in the United States is affected by hypertension. Two-thirds of blacks age 50 and older have high blood pressure. One-third of blacks age 18 and older show a tendency toward the condition, which, if uncontrolled, can lead to stroke, heart failure and kidney disease.

While individuals of all races and ethnicities develop hypertension, the disorder is twice as common in blacks as in whites. Cuban-Americans and New York Puerto Ricans are also thought to be more susceptible to hypertension than whites, while American Indians and Southwestern Latinos appear to have less hypertension.

While researchers propose both genetic and environmental theories to explain those differences, experts agree that monumental political and economic barriers stand in the way of reducing cases of hypertension in the black community.

During a recent meeting in Long Beach, the International Society on Hypertension in Blacks outlined several solutions aimed at breaking those barriers:

* Influencing food manufacturers to reduce the salt added to food. Many physicians believe blacks have a sensitivity to salt that contributes to high blood pressure.

* Improving school lunches through reductions in salt and fat. Dietary fat contributes to obesity, another risk factor in the development of hypertension. Research shows conditions leading to hypertension can begin in childhood.

* Providing free hypertension medication to those unable to afford it, through a program, supported by the government and pharmaceutical companies. High blood pressure can be successfully controlled with drugs.

Although hypertension afflicts blacks disproportionately, the disorder is not the problem of one race, said Dr. Jeremiah Stamler, a hypertension researcher at Northwestern University in Chicago.

“This is not a special pleading for blacks,” Stamler said of the society’s goals. “The high blood pressure problem in our country involves all populations--more so for blacks. High blood pressure is an unsolved, mass public-health problem for the whole nation.”

Researchers studying genetic causes of hypertension suggest the mechanism for excreting salt is less efficient among blacks. For instance, research at the University of Tennessee showed that although blacks and whites may have comparable daytime blood-pressure readings, the decline in blood pressure common at night is greater for whites than for blacks.

“This suggests blacks may have a different regulating mechanism for sodium excretion,” said Dr. Bruce Alpert of the University of Tennessee. “In blacks, it may take a higher blood pressure for kidneys to start to put out sodium.”

Thomas Wilson, a Drew University researcher, has even proposed a controversial theory to explain why blacks might have a genetic tendency toward hypertension.

Wilson recently reviewed records at the Public Record Office in London to analyze the amount of salt provided to slaves on slave ships.

He says that the Africans who survived the perilous journey on British slave ships in the 17th and 18th centuries were those who best stored salt. Salt might have been depleted during the voyages through excessive sweating, seasickness and diarrhea. The tendency of survivors to store salt might have conferred a salt sensitivity to their African-American descendants, Wilson said.

“This evidence, the first estimate of salt intake on slave ships, supports the hypothesis that the ‘fittest’ captives were also superior salt conservers,” Wilson said.

Other risk factors for hypertension include obesity and alcohol consumption. And intriguing new studies suggest environment may influence blood pressure.

Epidemiologist Marvin Bohnstedt of the California Department of Health Services found that black men living in neighborhoods fraught with crime and instability have higher rates of hypertension than black men living in less stressful neighborhoods.

Another study suggested black men with the so-called “Type-A” personality, described as hard-driven and struggling to get ahead, had higher blood pressures than black men with less intense personality traits.

While experts cannot agree on a unifying hypothesis to explain the high rate of hypertension among blacks, most support efforts to reduce dietary salt intake for all individuals as a preventive measure, Stamler said. A major international study, Intersalt, showed that as salt intake increases, the risk of hypertension rises.

But, he said, efforts by health professionals to curb salt intake have been thwarted by food manufacturers that continue to add unnecessary salt to processed foods.

“We need a population-wide and high-risk strategy,” Stamler said. “That’s why the reduction of salt is such an important strategy. If we wait until people become hypertensive, we will never solve the problem.”

Stamler charged that an industry lobbying group, the Salt Institute, has manipulated the findings of the Intersalt study to make the salt-hypertension link appear less certain. The Salt Institute maintains there is insufficient evidence to recommend that all Americans reduce their salt intake.

“We feel hypertensives who are salt sensitive should indeed reduce their intake of salt in a serious way. This is about 7% to 12% of the population,” said Louis Priebe, director of public policy for the Salt Institute, based in Alexandria, Va.

“What we have a problem with is the dietary recommendation, from various agencies, that all people should reduce their sodium. There has never been a causal relationship shown between sodium and hypertension. Healthy people who are cutting back on sodium are lulling themselves into a false sense of security. Smoking, obesity and alcohol are things they should be concerned about as risks for hypertension.”

But many medical experts say all Americans could reduce their risk of developing hypertension by cutting back on salt. The recommendation also applies to children, Alpert said. But again, political and economic barriers stand in the way, he said.

A study in a Memphis, Tenn., school district--in which school cooks added no salt to lunches--revealed that such dietary changes can reduce a child’s salt intake by two-thirds. According to Alpert, typical school lunches of pizza, tacos and snacks from vending machines are notoriously high in salt.

Alpert and Dr. Neil Shulman, board chairman of the International Society on Hypertension in Blacks Inc., criticized government nutritional regulations for schoolchildren. Under the federal Child Nutrition Program, schools must offer children a choice of whole or low-fat milk. Fat in milk, particularly whole milk, contributes to obesity and the risk of hypertension, they said.

“If you look at the school lunch program, a lot of these kids are exposed early to foods that are going to kill them,” Shulman said. “(Whole) milk is probably one of the worst things you can require they be exposed to. It’s very shortsighted to expose these kids to poor foods. If we can reach these people early, and get them oriented on a right diet, we can have a real big impact. But there is lot of politics behind these issues.”

Dairy industry leaders counter that milk is a nutritious food, high in the calcium, protein and minerals children need.

“The Dairy Council’s position has been that it’s important to have balance and variety in the diet and evaluate foods in terms of the overall diet,” said Lisa Coe of the United Dairy Industry Assn. in Rosemont, Ill. “In terms of school lunches, sometimes they are the only healthful and balanced meal children receive all day.”

The reduction of dietary salt and fat is important for all children but might have more impact on black children, Alpert said. He criticized the recent decision by the Los Angeles school board to lift its ban on the sale of junk food--typically high in fat, sugar and salt--in school cafeterias because the district needs the money generated by junk-food sales.

“Down to the age of 10, there are already differences in blood pressure (between races),” he said. “A population-wide reduction in sodium intake would benefit blacks more than whites, but it wouldn’t hurt anyone. Anything we can do as a population to reduce sodium will be helpful in a major way.”

Widespread use of anti-hypertensive drugs could prevent many cases of severe hypertension, which can lead to heart attacks, stroke or end-stage kidney disease, Shulman said. But anti-hypertensive drugs cost from $300 to $800 a year and are unaffordable to the poor and people without health insurance.

Shulman is leading a movement among health professionals to provide free hypertension drugs to the indigent. The proposed program would be supported by the government, private benefactors and the pharmaceutical industry.

Surveys show 36% of individuals with uncontrolled moderate or severe hypertension cannot afford medical care and drugs. Black men and women reported these barriers more frequently than whites, Shulman said.

A major pharmaceutical firm has been asked to consider a free drug program, and the federal government will be asked to lend support, said Dr. Harriet Dustan, a longtime hypertension researcher with the Veterans Administration Medical Center in Birmingham, Ala.

“As physicians, we’ve become increasingly concerned about the lack of government help for prevention,” Dustan said. “We need to have this problem of hypertension taken care of at a preventive level.”

HYPERTENSION AND SALT Blacks are more susceptible than whites to high blood pressure. Although medical experts are not certain what causes the problem in blacks, they believe salt sensitivity plays a major role. Many experts advise a reduction in dietary salt intake.

Compared to the entire population, black Americans experience:

* 5 to 7 times more cases of severe hypertension.

* 10 times more kidney failure.

* 2 times more strokes.

* 2 to 3 times more heart failure.

Source: International Society on Hypertension in Blacks Inc.