Clostridium difficile infection in patients discharged from US short-stay hospitals, 1996-2003

US hospital discharges for which Clostridium difficile-associated disease (CDAD) was listed as any diagnosis doubled from 82,000 (95% confidence interval [CI] 71,000-94,000) or 31/100,000 population in 1996 to 178,000 (95% CI 151,000-205,000) or 61/100,000 in 2003; this increase was significant between 2000 and 2003 (slope of linear trend 9.48; 95% CI 6.16-12.80, p = 0.01). The overall rate during this period was severalfold higher in persons >65 years of age (228/100,000) than in the age group with the next highest rate, 45-64 years (40/100,000; p < or = 0.001). CDAD appears to be increasing rapidly in the United States and is disproportionately affecting older persons. Clinicians should be aware of the increasing risk for CDAD and make efforts to control transmission of C. difficile and prevent disease.