In 2006, nearly 4.4 million hospital admissions, totaling $30.8 billion in costs, could have been potentially preventable with timely and effective ambulatory care or adequate patient self-management of the condition, according to a report published last month from the Agency for Healthcare Research and Quality (AHRQ).

Hospital costs for potentially preventable hospitalizations represented about one of every ten dollars of total hospital expenditures in 2006. Compared with 2004, there was no substantial change in the total number of admissions or total hospital costs for these potentially preventable conditions, according to the report.

The agency said that as many as 4.4 million hospital stays could possibly have been prevented with better ambulatory care, improved access to effective treatment or patient adoption of healthy behaviors.

Congestive heart failure and bacterial pneumonia were the two most common reasons for potentially preventable hospitalizations, accounting for half of the total hospital costs ($8.4 billion and $7.2 billion, respectively) for all preventable hospitalizations, AHRQ reported.

Eighteen percent of Medicare admissions were for a potentially preventable condition. In fact, Medicare patients contributed to $20.1 billion (67 percent) of total hospital costs for potentially preventable hospitalizations among adults.

Hospitalization rates for potentially preventable conditions were highest among residents in poorer communities but lowest among residents from wealthier communities. The report noted that the disparity was particularly evident for diabetes without complications, where the admission rate in the poorest communities was more than 400 percent higher than the rate in the wealthiest communities.

Also, patients with private insurance accounted for only 16 percent ($4.7 billion) of the total cost for potentially preventable admissions, as compared wtih 30 percent of the hospital costs for all other non-obstetric admissions. The agency said that only 7 percent of all privately insured admissions were for potentially preventable conditions--nearly half the percentage for all payors combined (13 percent).

The percent of total hospital costs attributable to patients with Medicaid and the uninsured was similar between potentially preventable hospital stays and all other non-obstetric hospitalizations (11 versus 12 percent for Medicaid patients, and 5 versus 5 percent for the uninsured). However, 12 percent of uninsured hospitalizations were potentially preventable, significantly higher than the 9 percent of Medicaid hospitalizations.

AHRQ's Prevention Quality Indicators (PQIs) were used to identify hospitalizations in 2006 for some chronic and acute conditions in adults and children.