The impact of dementia on hospital outcomes for elderly patients with sepsis: A population-based study

BACKGROUND: Prior studies have suggested that dementia adversely influences clinical outcomes and increases resource utilization in patients hospitalized for acute diseases. However, there is limited population-data information on the impact of dementia among elderly hospitalized patients with sepsis. METHODS: From the 2009–2011 National Hospital Discharge Database we identified hospitalizations in adults aged ≥65 years. Using ICD9-CM codes, we selected sepsis cases, divided them into two cohorts (with and without dementia) and compared both groups with respect to organ dysfunction, in-hospital mortality and the use of hospital resources. We estimated the impact of dementia on these primary endpoints through multivariate regression models. RESULTS: Of the 148 293 episodes of sepsis identified, 16 829 (11.3%) had diagnoses of dementia. Compared to their dementia-free counterparts, they were more predominantly female and older, had a lower burden of comorbidities and were more frequently admitted due to a principal diagnosis of sepsis. The dementia cohort showed a lower risk of organ dysfunction (adjusted OR: 0.84, 95% Confidence Interval [CI]: 0.81, 0.87) but higher in-hospital mortality (adjusted OR: 1.32, 95% [CI]: 1.27, 1.37). The impact of dementia on mortality was higher in the cases of younger age, without comorbidities and without organ dysfunction. The cases with dementia also had a lower length of stay (-3.87 days, 95% [CI]: -4.21, -3.54) and lower mean hospital costs (-3040€, 95% [CI]: -3279, -2800). CONCLUSIONS: This nationwide population-based study shows that dementia is present in a substantial proportion of adults ≥65s hospitalized with sepsis, and while the condition does seem to come with a lower risk of organ dysfunction, it exerts a negative influence on in-hospital mortality and acts as an independent mortality predictor. Furthermore, it is significantly associated with shorter length of stay and lower hospital costs.