Acute Crit Care.  2018 Nov;33(4):230-237. 10.4266/acc.2018.00514.

Impact of Socioeconomic Status on 30-Day and 1-Year Mortalities after Intensive Care Unit Admission in South Korea: A Retrospective Cohort Study

• Oh TK
• Jo J
• Jeon YT
• Song IA

• KMID: 2441240
• DOI: http://doi.org/10.4266/acc.2018.00514

Abstract

BACKGROUND
Socioeconomic status (SES) is closely associated with health outcomes, including mortality in critically ill patients admitted to intensive care unit (ICU). However, research regarding this issue is lacking, especially in countries where the National Health Insurance System is mainly responsible for health care. This study aimed to investigate how the SES of ICU patients in South Korea is associated with mortality.
METHODS
This was a retrospective observational study of adult patients aged ≥20 years admitted to ICU. Associations between SES-related factors recorded at the time of ICU admission and 30-day and 1-year mortalities were analyzed using univariable and multivariable Cox regression analyses.
RESULTS
A total of 6,008 patients were included. Of these, 394 (6.6%) died within 30 days of ICU admission, and 1,125 (18.7%) died within 1 year. Multivariable Cox regression analysis found no significant associations between 30-day mortality after ICU admission and SES factors (P>0.05). However, occupation was significantly associated with 1-year mortality after ICU admission.
CONCLUSIONS
Our study shows that 30-day mortality after ICU admission is not associated with SES in the National Health Insurance coverage setting. However, occupation was associated with 1-year mortality after ICU admission.

Keyword

critical care; intensive care unit; marital status; mortality; occupations; socioeconomic status

MeSH Terms

Adult
Cohort Studies*
Critical Care*
Critical Illness
Delivery of Health Care
Humans
Intensive Care Units*
Korea*
Marital Status
Mortality*
National Health Programs
Observational Study
Occupations
Retrospective Studies*
Social Class*

Figure

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  Figure 1. Flowchart for patient selection. ICU: intensive care unit.

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  Figure 2. Kaplan-Meier curve of overall survival time according to occupation after adjustment of covariates with criterion of P<0.05 in multivariable Cox regression analysis for 1-year mortality. Included covariates are sex, age, body mass index, Charlson comorbidity index, Acute Physiology and Chronic Health Evaluation II, diagnosis of cancer, postoperative intensive care unit (ICU) admission and year of ICU admission.

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