The CDC analyzes 2008 deaths. (AP Photo/Dr. Scott M. Lieberman)

The average life expectancy of all U.S. residents increased between 2007 and 2008, but the death rate for U.S. residents ages 55 to 64 and ages 75 and older increased.

Researchers at the U.S. Centers for Disease Control and Prevention (CDC) have reported on mortality trends in a final report on U.S. deaths that took place in 2008.

About 2.5 million people died in the United States in 2008, and the age-adjusted death rate fell 0.2%, to 758 deaths per 100,000 lives.

The overall death rate for many conditions fell, but the overall death rate from some common causes of death, including chronic lung disease and Alzheimer’s disease, rose.

The death rate from lung disease, or “chronic lower respiratory diseases,” increased 7.8%, and the death rate from Alzheimer’s disease increased 7.5%. The death rate for deaths caused by high blood pressure increased 4.1%.

For peoples ages 85 and older, the death rate from lung disease increased about 10%, to 656 per 100,000 lives, and the death rate from Alzheimer’s increased 7.2%, to 910 per 100,000 lives.

Coding changes may be responsible for much of the increase in the chronic lung disease and Alzheimer’s death rates in 2008, officials say.

But the overall 2008 death rate for deaths associated with pneumonia and influenza also increased — 4.3% — and researchers found a noticeable increase in the total death rate for U.S. residents ages 85 and older from all causes.

The death rate for U.S. residents ages 55 to 65 and for residents ages 75 to 84 increased slightly. The rate creeped up 0.1%, to 879 per 100,000 lives, for people ages 55 to 64, and it creeped up 0.2%, to 5,018 per 100,000 lives, for people ages 75 to 84.

The death rate for people ages 85 and older jumped 0.5%, to 13,015 per 100,000 lives. The death rate for men rose 0.1%, and the death rate for women rose 0.7%.