Increasing rates of hospitalization due to septicemia in the US elderly population, 1986-1997.

Rates of hospitalization due to septicemia (International Classification of Diseases, Ninth Revision, Clinical Modification, code 038) in the US elderly population for 1986-1997 were examined, using Medicare administrative data. Age group-, sex-, and race-adjusted rates more than doubled from 1986 through 1997, from 3.42 to 7.42 per 1000 beneficiaries. The 1997 rates of septicemia increased with age, from 4.47 per 1000 beneficiaries among persons 65-74 years old to 18.1 per 1000 beneficiaries among persons > or =85 years old. The rates of septicemia were slightly greater among men (7.46 per 1000 beneficiaries) than among women (7.39 per 1000 beneficiaries) and were higher among blacks (13.61 per 1000 beneficiaries) than among whites (6.89 per 1000 beneficiaries). The most likely sites of the origin of the septicemia were the urinary tract (40.1%) and lungs (15.3%). Escherichia coli and Staphylococcus species were the most frequently reported organisms. Diabetes was listed as a comorbidity in 24.5% of the hospitalizations. We estimate that the cost to Medicare for septicemia hospitalizations in 1997 was >$1.8 billion.