Original Study| Volume 21, ISSUE 12, P1869-1878.e10, December 2020

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Factors Associated With 30-Day Rehospitalization and Mortality in Older Patients After a Pneumonia Admission

Published:October 06, 2020DOI:



      Short-term rehospitalization and mortality are common events in older patients after a pneumonia admission, yet little knowledge exists on how to identify the patients at risk of these events. This knowledge is needed to ensure that health care attention is given to those with the highest needs. We therefore aimed to identify factors of importance for short-term rehospitalization and mortality in older patients after admission for pneumonia.


      Population-based cohort study.


      The Danish nationwide registries.


      In total, 246,245 individuals aged 65-99 years who experienced 298,564 admissions for pneumonia from 2000 to 2016.


      The explored factors in patients were demographic characteristics, health-seeking behavior, comorbidity, and medication use. A Cox proportional hazards model was used to calculate hazard ratios (HRs) for 30-day rehospitalization and 30-day mortality with 95% confidence intervals (CIs).


      Of the 298,564 admissions for pneumonia, 23.0% were rehospitalized and 8.1% died within 30 days of follow-up. Most of the investigated factors were significantly associated with these 2 outcomes. The HRs for rehospitalization ranged from 0.80 (95% CI 0.75-0.85) for old vs young age to 4.29 (95% CI 4.05-4.54) for many vs no prior admissions, whereas the HRs for mortality ranged from 0.87 (95% CI 0.83-0.91) for any vs no practical home care to 5.47 (95% CI 5.08-5.88) for old vs young age. Number of comorbidities, medications, and prior contacts to the health care system were associated with higher risk of both rehospitalization and mortality in a dose-response manner.

      Conclusions and Implications

      This study identified several potential factors of importance for short-term rehospitalization and mortality in older patients discharged after pneumonia. This knowledge can help physicians identify the patients with the highest need of care after admission for pneumonia, thus enabling efficient discharge planning and high-quality provision of care in primary care settings.


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