Nearly 5 million hospital admissions in the US might have been prevented in 2000 if patients had received high quality primary and preventive care, according to a government report issued on Thursday.

These potentially avoidable hospitalizations cost the health care system more than $26.5 billion, the Agency for Healthcare Research and Quality found.

The survey of hospitals across the country looked at statistics on admissions from 1994 to 2000. It found that possibly preventable admissions for chronic pulmonary disease increased by 20 percent, while admissions for high blood pressure went up 13 percent and for bacterial pneumonia, 9 percent.

The report does not lay blame in any one place, but it adds one piece to the puzzle of ballooning health care costs in the United States. A Commonwealth Fund survey also published on Thursday found that health insurance premiums rose 11.2 percent in 2004 from 2003.

Even a little bit of extra care could save a lot of money, the agency found.

“Assuming an average cost of $5,300 per admission, even a 5 percent decrease in the rate of potentially avoidable hospitalizations could result in a cost savings of more than $1.3 billion,” the report reads.

Poverty seems to be a factor.

“Residents from areas with the lowest median incomes (less than $25,000) have the highest rates of admission for every preventable hospitalization indicator,” the report reads.

And rural residents seem to land in the hospital more often for emergencies, perhaps because it is hard for them to get to hospitals and clinics routinely.

The report, available on the Internet at http://www.ahrq.gov/data/hcup/factbk5/factbk5a.htm, finds that better patient education and better technology has led to improvements.

“Hospital admission rates for treatment of angina (chest pain) without a procedure dropped 71 percent,” the report reads.

“Hospitalizations for uncontrolled diabetes without complications declined nearly 30 percent. Rates of hospitalization for adult asthma and pediatric gastroenteritis each decreased 20 percent.”