Acute Crit Care.  2018 Aug;33(3):135-145. 10.4266/acc.2018.00164.

Changes in the Characteristics and Long-term Mortality Rates of Intensive Care Unit Patients from 2003 to 2010: A Nationwide Population-Based Cohort Study Performed in the Republic of Korea

Affiliations
  • 1Department of Internal Medicine, Kangwon National University Hospital, Chuncheon, Korea.
  • 2Department of Internal Medicine, Kangwon National University School of Medicine, Chuncheon, Korea. medfman@gmail.com
  • 3Division of Allergy and Clinical Immunology, Kangwon National University School of Medicine, Chuncheon, Korea.
  • 4Department of Statistics, Kangwon National University, Chuncheon, Korea.
  • 5Department of Neurology, Kangwon National University School of Medicine, Chuncheon, Korea.

Abstract

BACKGROUND
There are few studies on intensive care unit (ICU) patients in the Republic of Korea. We analyzed the characteristics and mortality changes of all ICU patients over the last 8 years.
METHODS
This study used the cohort of the National Health Insurance Corporation, which provides medical care to all residents of the Republic of Korea. The cohort consists of patients aged 20 years or older between 2003 and 2010 with a history of ICU admission. We analyzed changes in sex, age, household income, number of hospital beds, emergency admissions, and reasons for admission using the Cochran-Armitage trend test. The adjusted hazard ratios (HRs) of mortality according to these variables and year of admission were calculated by Cox proportional hazards regression.
RESULTS
The proportion of patients aged ≥70 years increased over that period, as did their average age (by 3.6 years). During the 8-year study period, the 3-year mortality rate was 32.91%-35.83%. The overall mortality was higher in males and older patients, in those with a lower household income and higher Charlson Comorbidity Index (CCI) score, those admitted to a hospital with a smaller number of beds, and those admitted via the emergency room. There was no significant change in crude mortality rate over the 8-year study period; however, the adjusted HR showed a decreasing trend.
CONCLUSIONS
Patients admitted to the ICU were older and had higher CCI score. Nevertheless, there was a temporal trend toward a decrease in the HR of long-term mortality.

Keyword

cohort studies; intensive care unit; mortality

MeSH Terms

Cohort Studies*
Comorbidity
Critical Care*
Emergencies
Emergency Service, Hospital
Family Characteristics
Humans
Intensive Care Units*
Male
Mortality*
National Health Programs
Republic of Korea*

Figure

  • Figure 1. Flow chart of the study selection process. NHIS-NSC: National Health Insurance Service-National Sample Cohort; ICU: intensive care unit.

  • Figure 2. Forest plot of adjusted hazard ratio and 95% confidence interval in Cox models adjusted for sex, age, household income, Charlson Comorbidity Index, number of hospital beds, admission via the emergency room, and admission reason.

  • Figure 3. The adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) of mortality and forest plots of HRs adjusted for sex, age, household income, Charlson comorbidity index, number of hospital beds, and admission via the emergency room in stratified Cox models by admission reason.


Cited by  2 articles

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Kwangha Lee
Acute Crit Care. 2018;33(4):269-270.    doi: 10.4266/acc.2018.00346.

Long-term mortality of patients discharged from the hospital after successful critical care in the ICU in Korea: a retrospective observational study in a single tertiary care teaching hospital
Se Hee Na, Cheung Soo Shin, Gwan Ho Kim, Jae Hoon Kim, Jong Seok Lee
Korean J Anesthesiol. 2020;73(2):129-136.    doi: 10.4097/kja.d.18.00275.


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