People with HIV can get 24 extra years of life from modern treatments -- at a total cost of $618,900 in 2004 dollars.

That finding comes from a Cornell/Johns Hopkins/Harvard/Boston University research team that analyzed the costs and benefits of modern HIV treatment.

When first introduced in 1996, a combination of then-new HIV drugs increased life expectancy by four years.

Now there are 24 HIV drugs on the market. The benefits are huge. So are the costs.

More Than 1 Million Americans Living With HIV

AIDS Cure Possible, Studies Suggest

"We have been very successful in HIV treatment, extending lives by at least 24 years," Cornell researcher Bruce R. Schackman, PhD, tells WebMD. "As with many health care innovations, success is expensive. We have to make sure we have enough funds available so that everyone can get that life extension with the best care available."

Doctors don't usually start HIV treatment right away. That's because it takes time for the AIDS virus to wear down the immune system.

Treatment usually starts when immune cells called CD4 T cells decline to a certain level -- typically 350 cells per microliter of blood.

When treatment does begin, the average monthly cost is about $2,100. The cost of drugs is nearly three-fourths of the lifetime expense.

Unfortunately, one in four people with HIV don't know they're infected. They find out only when their immune system collapses.

The cost of treatment started at this late stage averages $4,700 per month. That's because hospital costs rise to almost half the lifetime expense.

In the last 10 years, the U.S. has tripled its spending on HIV-related medical care. Yet it's falling behind.

Future costs, Schackman and colleagues estimate, will be $12.1 billion per year. Drugs will make up 70 percent of the cost.

"Access to HIV care may become increasingly difficult unless more government funds become available or the cost of HIV care is reduced," Johns Hopkins researcher Richard D. Moore says in a news release.

Of course, the least expensive option would be to prevent the estimated 40,000 new HIV infections that occur each year in the U.S.

"Successful prevention of HIV can prevent a lot of cost," Schackman says. "There is a lot of value to programs that prevent HIV."

Schackman and colleagues report their findings in the November issue of Medical Care.

AIDS Virus May Be Weakening

AIDS Taking on a Female Face

By Daniel J. DeNoon, reviewed By Louise Chang, MD

SOURCES: Schackman, B. Medical Care, November 2006; vol 44: pp 990-997. News release, Weill Medical College of Cornell University. Bruce R. Schackman, PhD, chief, division of health policy, Weill Cornell Medical College.