Newswise — Roughly one-quarter of all hospital patients were readmitted over a two-year period for the same conditions that prompted their initial hospitalization, according to the latest News and Numbers by the Agency for Healthcare Research and Quality.

According to the federal agency's analysis of data on 15 million patients in 12 states in 2006 and 2007, more than a third of those who had hardening of the arteries, called coronary atherosclerosis, were readmitted at least once to the hospital during the period . Multiple readmissions were also seen for 30 percent of patients with uncomplicated diabetes, 28 percent with high blood pressure and 21 percent with asthma.

AHRQ also found that:

o Among Medicare patients, 42 percent experienced multiple hospital admissions and 38 percent multiple emergency department visits. For Medicaid patients, 23 percent experienced multiple hospital admissions and 50 percent went to the emergency department more than once.

o About 22 percent of uninsured patients had muliple hospital readmissions and 38 percent had multiple hospital emergency department vists but were not admitted.

o Privately insured patients were the least likely to require multiple hospital readmissions (19 percent) or make multiple visits to the emergency department (29 percent).

While some patients may be readmitted because of the severity and complexity of their underlying condition, research shows that many repeat admissions can be avoided if patients have better outpatient care. Readmissions can also drive up health care costs.

This AHRQ News and Numbers is based on data in Hospital Readmissions and Multiple Emergency Department Visits, in Selected States, 2006-2007 (http://www.hcup-us.ahrq.gov/reports/statbriefs/sb90.pdf). The report uses statistics from the HCUP State Inpatient Databases and HCUP State Emergency Department Databases for 12 states: Arizona, California, Florida, Hawaii, Massachusetts, Missouri, Nebraska, New Hampshire, New York, South Carolina, Tennessee, and Utah.