Population Burden of Long-Term Survivorship After Severe Sepsis in Older Americans

Objectives To ascertain the absolute number of Medicare beneficiaries surviving at least 3years after severe sepsis and to estimate their burden of cognitive dysfunction and disability. Design Retrospective cohort analysis of Medicare data. Setting All short-stay inpatient hospitals in the United States, 1996 to 2008. Participants Individuals aged 65 and older. Measurements Severe sepsis was detected using a standard administrative definition. Case-fatality, prevalence, and incidence rates were calculated. Results Six hundred thirty-seven thousand eight hundred sixty-seven Medicare beneficiaries were alive at the end of 2008 who had survived severe sepsis 3 or more years earlier. An estimated 476,862 (95% confidence interval (CI)=455,026498,698) had functional disability, with 106,311 (95% CI=79,692133,930) survivors having moderate to severe cognitive impairment. The annual number of new 3-year survivors after severe sepsis rose 119% during 1998 to 2008. The increase in survivorship resulted from more new diagnoses of severe sepsis rather than a change in case-fatality rates; severe sepsis rates rose from 13.0 per 1,000 Medicare beneficiary-years to 25.8 (P<.001), whereas 3-year case fatality rates changed much less, from 73.5% to 71.3% (P<.001) for the same cohort. Increasing rates of organ dysfunction in hospitalized individuals drove the increase in severe sepsis incidence, with an additional small contribution from population aging. Conclusions Sepsis survivorship, which has substantial long-term morbidity, is a common and rapidly growing public health problem for older Americans. There has been little change in long-term case-fatality, despite changes in practice. Clinicians should anticipate more-frequent sequelae of severe sepsis in their patient populations.