by Will Dunham

Last Updated: 2008-06-12 8:09:21 -0400 (Reuters Health)

WASHINGTON (Reuters) – U.S. life expectancy hit a record high of 78.1 years in 2006 while Alzheimer’s disease crept up a notch to No. 6 on the list of leading causes of death, U.S. health officials said on Wednesday.

Rates for 14 of the top 15 causes of death fell in 2006, the U.S. Centers for Disease Control and Prevention said in a report. Influenza and pneumonia deaths had the steepest drop, at 13%, compared to the previous year.

The life expectancy at birth of 78.1 years was up from a then-record of 77.8 years in 2005, continuing a rise going back decades, the CDC said.

Life expectancy for women (80.7 years) continued to exceed that for men (75.4 years). Racial disparities persisted as well, with white women’s life expectancy at 81 years compared to 76.9 for black women and white men’s life expectancy at 76 years compared to 70 for black men.

Infant mortality fell in 2006 to 6.7 infant deaths per 1,000 live births, down from 6.9 per 1,000 in 2005, according to the CDC. It still remains higher than many rich nations.

Heart disease, which killed 629,191 people, and cancer, which killed 560,102 people, remained the two top causes of death, followed by stroke, chronic lower respiratory diseases such as emphysema and accidents.

Alzheimer’s disease, the most common form of dementia in the elderly, leapfrogged diabetes to become the sixth-leading cause of death, killing 72,914 Americans in 2006.

The number of people with Alzheimer’s is projected to rise steadily in the coming decades as the proportion of elderly people in the U.S. population increases.

The Alzheimer’s Association said that up to 5.2 million Americans have Alzheimer’s disease and that by 2010, there will be almost a half million new cases per year. By 2050 it expects nearly 1 million new U.S. cases each year.

Diabetes fell to No. 7 on the list, where Alzheimer’s had been the previous year, the CDC said.

The death rate from diabetes fell 5% in 2006 from 2005. More people are developing the most common form of the disease, which is known as type 2 diabetes and is closely tied to obesity and a sedentary lifestyle. But treatment for the diabetes is improving.

Suicide was the 11th leading cause of death (32,185 such deaths) and murder was the 15th leading cause (18,029), the CDC said. Of the top 15 causes of death, only kidney disease, at number 9, did not drop. Its rate remained steady, the CDC said.

The overall number of deaths in 2006 in the United States, a country of about 300 million people, was 2,425,900, a decrease of 22,117 from the 2005 total, the CDC said. The decrease was likely due to a milder influenza season in 2006 than in the previous year, the CDC said.

The findings were based on data from nearly all death certificates nationwide, the CDC said.

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