More than 434,000 Americans died in 1988 from health problems caused by smoking, an 11 percent increase over the 1985 total, according to a report published today by the federal Centers for Disease Control.

Smoking is the No. 1 cause of preventable deaths in the United States, responsible for about one-fifth of all deaths. Its annual death toll is rising -- despite declining smoking rates -- because the growing population of older Americans includes many current and former smokers who are at increased risk of heart disease, lung cancer and other disorders.

"Eleven Marines died in a fight in the gulf" Wednesday, said William L. Roper, director of the CDC. "That's a terrible tragedy that people have had on their minds. Think about almost half a million people who died in 1988 due to smoking. These are real people who died needlessly. . . . Somehow, we don't seem to make the same connection."

The new CDC estimates, published in the agency's weekly bulletin, were calculated using 1988 death rates from illnesses for which smoking is a well-established risk factor, and 1988 smoking rates for American men and women according to race and age group.

The estimates include deaths from various cancers, heart disease, high blood pressure, stroke and lung diseases, as well as burn deaths and infant deaths caused by conditions related to mothers' smoking during pregnancy.

The estimates also include about 3,825 deaths caused by "passive smoking," a much lower figure than those found in some other recent studies. Thomas E. Novotny, a physician at the CDC's Office on Smoking and Health who compiled the report, said the agency chose to include passive smoking deaths from lung cancer but not from heart disease, because the link between passive smoking and heart disease has been less extensively documented.

A report published last month by researchers at the University of California at San Francisco estimated that passive smoking causes 37,000 heart disease deaths in the United States each year.

CDC officials said the new estimates represent the minimum number of deaths caused by smoking. "This is a conservative estimate. We believe the real numbers are higher," said Roper. "But we are trying to present evidence that is very tightly drawn, so we can say with great confidence that the numbers are at least this high."

Heart attack deaths attributable to smoking declined between 1985 and 1988, reflecting a nationwide drop in heart attack deaths. But the decline was more than offset by an increase in smoking-related deaths from lung cancer and chronic lung diseases such as emphysema, the report said. The figures clearly indicate that lung cancer has surpassed breast cancer as the commonest fatal cancer in women, Roper said.

The CDC also included, for the first time, smoking-related deaths from several other heart disorders, including cardiac arrest and cor pulmonale, a form of heart failure caused by chronic lung disease. Roper emphasized, however, that the increase over the agency's former estimate of 390,000 deaths a year "is not just an artifact of the methodology. There is a real increase."

The death rate from diseases caused by smoking was twice as high for men as for women, reflecting the fact that past smoking rates have been higher for men. The rate was also higher for blacks than for whites, and the figures show that blacks tend to die at younger ages than whites from smoking-related diseases.

Novotny said infant mortality figures indicate that about 10 percent of deaths in children less than 1 year old could be prevented if all women refrained from smoking during pregnancy and around infants. Smoking during pregnancy increases a woman's chances of having a premature or low-birthweight infant. Exposure to smoke also raises a baby's risk of lung disease and sudden infant death syndrome.