Mortality following acute medical admission in Denmark: a feasibility study

Morten Schmidt¹, Sussie Antonsen¹, Betina Hansen¹, Jens Møller², Carsten Thordal², Henrik Toft Sørensen^1
1Department of Clinical Epidemiology, Aarhus University Hospital, Aarhus, Denmark; ²Department of Endocrinology and Internal Medicine, Aarhus University Hospital, Aarhus, Denmark

Background: As the population ages, an increasing number of acute medical patients will be older and have comorbidities that may interact with their primary admission condition and worsen their prognosis.
Objectives: To examine whether 6-month mortality following acute medical admission was associated with gender, age, or comorbidity.

Methods: We used the Danish National Patient Registry, covering all Danish hospitals, to identify all acute medical admissions to Aarhus University Hospital during 2008 and comorbidities. We obtained mortality data from the Danish Civil Registration System. We computed mortality risks and hazard ratios with 95% confidence intervals (CIs) for gender, age, and comorbidity groups.

Results: We identified 3,727 patients (53.6% women) with a median age of 63 years for women and 60 years for men. The overall 6-month mortality rate was 12.8%. The adjusted hazard ratio was 2.77 (95% CI, 2.11–3.64) for patients aged 65–80 years and 5.25 (95% CI, 4.06–6.80) for patients older than 80 years, compared with patients younger than 65 years. The adjusted hazard ratio was 2.43 (95% CI, 1.82–3.24) and 3.87 (95% CI, 2.91–5.15) for patients with moderate and high comorbidity, respectively, compared with low comorbidity.
Conclusion: Age and comorbidity were important predictors of mortality after acute medical admission.

Keywords: cohort study, comorbidity, epidemiology, hospital admission, internal medicine, prognosis, registries