Researchers used data from the Healthcare Cost and Utilization Project (HCUP) database from the Agency for Healthcare Research and Quality (AHRQ) to examine trends in COPD readmission in California between 2005 and 2011. Ultimately, data from 480 hospitals were included. Highlights of their findings include:

• Younger COPD patients were significantly more likely to be readmitted than patients older than 65; those aged 40-60 were at highest risk for readmission.
• Inconsistent with previous research, COPD readmission rates were highest during the summer months.
• In younger patients (<65), insurance type mattered; patients with private insurance were less likely to be readmitted than their same-aged peers on Medicare. Both groups were less likely to be readmitted than same-aged individuals using Medicaid.
• Those discharged to home health or who leave against medical advice (AMA) were significantly more likely to be readmitted; those transferred to another hospital were significantly less likely to readmit.

Full findings, including analyses by comorbidity, gender and race as well as of length of stay and mortality, are presented in detail.