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

Three-year mortality, readmission, and medical expenses in critical care survivors: A population-based cohort study

BACKGROUND

Due to the increasing number of critical care survivors, population-based studies on the long-term outcomes after discharge are necessary to inform local decision-making.

OBJECTIVES

This study aimed to investigate mortality and its risk factors, readmissions, and medical expenses of intensive care unit survivors for 3 years after hospital discharge.

METHODS

This retrospective study analysed data from the National Health Insurance Service-National Sample Cohort in Korea. Of the 195,702 patients who survived and were discharged from hospital in 2012, 2693 intensive care unit patients were assigned to the case group for the study, and the remaining 193,009 were assigned to the comparison group. The primary outcome was all-cause mortality for 3 years after discharge. Secondary outcomes were all-cause hospital readmission and medical expenses in 3 years. We analysed risk factors for mortality using the Cox proportional hazard regression. The differences in hospital readmission and medical expenses between the case and comparison groups were analysed by multivariate logistic regression and independent t-tests.

RESULTS

The 1-year, 2-year, and 3-year cumulative mortality rates in the case group were 15.9%, 20.5%, and 24.4%, respectively, and older age, disability, medical admission, and longer hospital stay increased mortality. Almost 40% of intensive care unit survivors were readmitted to hospital within 6 months of discharge, and their odds of being readmitted were significantly higher than those of the comparison group. Medical expenses were also significantly higher in the case group, with the highest paid within 6 months.

CONCLUSIONS

Mortality, hospital readmission, and medical expenses for intensive care unit survivors were the worst within 6 months of discharge. In light of the long-term recovery trajectory of critical illness, it is necessary to investigate what factors may have contributed to the negative outcome during this period. Further research is needed to determine which services primarily contributed to the increase in medical expenses.

Change in management and outcome of mechanical ventilation in Korea: a prospective observational study

BACKGROUND/AIMS

There are few studies describing contemporary status of mechanical ventilation in Korea. We investigated changes in management and outcome of mechanical ventilation in Korea.

METHODS

International, prospective observational cohort studies have been conducted every 6 years since 1998. Korean intensive care units (ICUs) participated in 2010 and 2016 cohorts. We compared 2016 and 2010 Korean data.

RESULTS

Two hundred and twenty-six patients from 18 ICUs and 275 patients from 12 ICUs enrolled in 2016 and 2010, respectively. In 2016 compared to 2010, use of non-invasive ventilation outside ICU increased (10.2% vs. 2.5%, p = 0.001). Pressure-control ventilation was the most common mode in both groups. Initial tidal volume (7.1 mL/kg vs. 7.4 mL/kg, p = 0.372) and positive end-expiratory pressure (6 cmH2O vs. 6 cmH2O, p = 0.141) were similar, but peak pressure (22 cmH2O vs. 24 cmH2O, p = 0.011) was lower in 2016. More patients received sedatives (70.7% vs. 57.0%, p = 0.002) and analgesics (86.5% vs. 51.1%, p < 0.001) in 2016. The awakening (48.4% vs. 31.0%, p = 0.002) was more frequently attempted in 2016. The accidental extubation rate decreased to one tenth of what it was in 2010 (1.1% vs. 10.2%, p < 0.001). The ICU mortality did not change (31.4% 35.6%, p = 0.343) but ICU length of stay showed a decreasing trend (9 days vs. 10 days, p = 0.054) in 2016.

CONCLUSION

There were temporal changes in care of patients on mechanical ventilation including better control of pain and agitation, and active attempt of awakening.

Trends in Mortality after Intensive Care of Patients with Aneurysmal Subarachnoid Hemorrhage in Finland in 2003-2019: A Finnish Intensive Care Consortium study

Background

Previous studies suggest that case mortality of aneurysmal subarachnoid hemorrhage (aSAH) has decreased during the last decades, but most studies have been unable to assess case severities among individual patients. We aimed to assess changes in severity-adjusted aSAH mortality in patients admitted to intensive care units (ICUs).

Methods

We conducted a retrospective, register-based study by using the prospectively collected Finnish Intensive Care Consortium database. Four out of five ICUs providing neurosurgical and neurointensive care in Finland participated in the Finnish Intensive Care Consortium. We extracted data on adult patients admitted to Finnish ICUs with aSAH between 2003 and 2019. The primary outcome was 12-month mortality during three periods: 2003–2008, 2009–2014, and 2015–2019. Using a multivariable logistic regression model—with variables including age, sex, World Federation of Neurological Surgeons grade, preadmission dependency, significant comorbidities, and modified Simplified Acute Physiology Score II—we analyzed whether admission period was independently associated with mortality.

Results

A total of 1,847 patients were included in the study. For the periods 2003–2008 and 2015–2019, the mean number of patients with aSAH admitted per year increased from 81 to 123. At the same time, the patients’ median age increased from 55 to 58 years (p = 0.001), and the proportion of patients with World Federation of Neurological Surgeons grades I–III increased from 42 to 58% (p < 0.001). The unadjusted 12-month mortality declined from 30% in 2003–2008 to 23% in 2015–2019 (p = 0.001), but there was no statistically significant change in severity-adjusted mortality.

Conclusions

Between 2003 and 2019, patients with aSAH admitted to ICUs became older and the proportion of less severe cases increased. Unadjusted mortality decreased but age and case severity adjusted–mortality remained unchanged.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12028-021-01420-z.

Long-term trends in critical care admissions in Wales

As national populations age, demands on critical care services are expected to increase. In many healthcare settings, longitudinal trends indicate rising numbers and proportions of patients admitted to ICU who are older; elsewhere, including some parts of the UK, a decrease has raised concerns with regard to rationing according to age. Our aim was to investigate admission trends in Wales, where critical care capacity has not risen in the last decade. We used the Secure Anonymised Information Linkage Databank to identify and characterise critical care admissions in patients aged ≥ 18 years from 1 January 2008 to 31 December 2017. We categorised 85,629 ICU admissions as youngest (18-64 years), older (65-79 years) and oldest (≥ 80 years). The oldest group accounted for 15% of admissions, the older age group 39% and the youngest group 46%. Relative to the national population, the incidence of admission rates per 10,000 population in the oldest group decreased significantly over the study period from 91.5/10,000 in 2008 to 77.5/10,000 (a relative decrease of 15%), and among the older group from 89.2/10,000 in 2008 to 75.3/10,000 in 2017 (a relative decrease of 16%). We observed significant decreases in admissions with high comorbidity (modified Charlson comorbidity index); increases in the proportion of older patients admitted who were considered 'fit' rather than frail (electronic frailty index); and decreases in admissions with a medical diagnosis. In contrast to other healthcare settings, capacity constraints and surgical imperatives appear to have contributed to a relative exclusion of older patients presenting with acute medical illness.

Neurointensive care results and risk factors for unfavorable outcome in aneurysmatic SAH: a comparison of two age groups

Background

The mean age of actively treated subarachnoid hemorrhage (SAH) patients is increasing. We aimed to compare outcomes and prognostic factors between older and younger SAH patients.

Methods

A retrospective single-center analysis of aneurysmal SAH patients admitted to a neuro-ICU during 2014–2019. We defined older patients as ≥70 years and younger patients as <70 years. For every older patient, we identified three younger patients with the same World Federation of Neurological Surgeons (WFNS) grade. We only included patients receiving active aneurysm treatment. Favorable functional outcome, defined as a Glasgow Outcome Scale (GOS) of 4–5 at 12 months, was our primary outcome. We used logistic regression to compare prognostic factors between the groups.

Results

Ninety-five (85%) of 112 older patients and 317 (94%) of 336 younger patients received aneurysm treatment. Of the younger patients, 91% with a good-grade SAH (WFNS I-III) had a favorable outcome compared to 52% in the older good-grade SAH group. In poor-grade patients (WFNS IV-V), favorable outcome was seen in 51% of younger patients, compared to 24% of older patients. Acute hydrocephalus and intracerebral hemorrhage were associated with unfavorable outcome in the younger (OR 4.7, 95% CI 2.6–8.4, and OR 3.7, 95% CI 2.1–6.4), but not in the older patients (OR 1.8, 95% CI 0.8–4.2, and OR 1.3, 95% CI 0.5–3.1, respectively).

Conclusions

In actively treated SAH patients, age was a major determinant of outcome. Factors reflecting increases in intracranial pressure associated with outcome only among younger patients.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00701-021-04731-4.

Characteristics and outcomes of patients admitted to adult intensive care units in Hong Kong: a population retrospective cohort study from 2008 to 2018

Background

Globally, mortality rates of patients admitted to the intensive care unit (ICU) have decreased over the last two decades. However, evaluations of the temporal trends in the characteristics and outcomes of ICU patients in Asia are limited. The objective of this study was to describe the characteristics and risk adjusted outcomes of all patients admitted to publicly funded ICUs in Hong Kong over a 11-year period. The secondary objective was to validate the predictive performance of Acute Physiology And Chronic Health Evaluation (APACHE) IV for ICU patients in Hong Kong.

Methods

This was an 11-year population-based retrospective study of all patients admitted to adult general (mixed medical-surgical) intensive care units in Hong Kong public hospitals. ICU patients were identified from a population electronic health record database. Prospectively collected APACHE IV data and clinical outcomes were analysed.

Results

From 1 April 2008 to 31 March 2019, there were a total of 133,858 adult ICU admissions in Hong Kong public hospitals. During this time, annual ICU admissions increased from 11,267 to 14,068, whilst hospital mortality decreased from 19.7 to 14.3%. The APACHE IV standard mortality ratio (SMR) decreased from 0.81 to 0.65 during the same period. Linear regression demonstrated that APACHE IV SMR changed by − 0.15 (95% CI − 0.18 to − 0.11) per year (Pearson’s R = − 0.951, p < 0.001). Observed median ICU length of stay was shorter than that predicted by APACHE IV (1.98 vs. 4.77, p < 0.001). C-statistic for APACHE IV to predict hospital mortality was 0.889 (95% CI 0.887 to 0.891) whilst calibration was limited (Hosmer–Lemeshow test p < 0.001).

Conclusions

Despite relatively modest per capita health expenditure, and a small number of ICU beds per population, Hong Kong consistently provides a high-quality and efficient ICU service. Number of adult ICU admissions has increased, whilst adjusted mortality has decreased over the last decade. Although APACHE IV had good discrimination for hospital mortality, it overestimated hospital mortality of critically ill patients in Hong Kong.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40560-020-00513-9.

Retrospective Analysis of Long-Term Survival in Very Elderly (age ≥80) Critically Ill Patients of a Medical Intensive Care Unit at a Tertiary Care Hospital in Korea

Background

The purpose of this study was to evaluate the long-term survival rates of very elderly (age ≥80) critically ill patients admitted to a medical intensive care unit (MICU) at a regional tertiary-care hospital in Korea.

Methods

We retrospectively analyzed data from patients who survived after discharged from the MICU of our hospital. Survival rates at 90 days, 1 year, 2 years, and 3 years were assessed between patients age ≥80 and those age <80. Survival status was evaluated using the National Health Insurance Service data.

Results

A total of 468 patients were admitted, 286 (179 males, 97 females; mean age, 70.18±13.2) of whom survived and were discharged soon after their treatment. Among these patients, 69 (24.1%) were age ≥80 and 217 (75.9%) were age <80. The 90-day, 1-year, 2-year, and 3-year survival rates of patients age ≥80 were significantly lower than those in patients age <80 (50.7%, 31.9%, 15.9% and 14.5% vs. 68.3%, 54.4%, 45.6%, and 40.1%, respectively) (p<0.01). The Kaplan-Meier survival curves showed significantly lower survival rates in patients age ≥80 than in those age <80 (p=0.001).

Conclusion

The poor rates of long-term survival in very elderly (age ≥80) and critically ill patients admitted to an ICU should be considered while managing and treating them.

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

Background

The long-term outcomes of patients discharged from the hospital after successful care in intensive care unit (ICU) are not briskly evaluated in Korea. The aim of this study was to assess long-term mortality of patients treated in the ICU and discharged alive from the hospital and to identify predictive factors of mortality.

Methods

In 3,679 adult patients discharged alive from the hospital after ICU care between 2006 and 2011, the 1-year mortality rate (primary outcome measure) was investigated. Various factors were entered into multivariate analysis to identify independent factors of 1-year mortality, including sex, age, severity of illness (APACHE II score), mechanical ventilation, malignancy, readmission, type of admission (emergency, elective surgery, and medical), and diagnostic category (trauma and non-trauma).

Results

The 1-year mortality rate was 13.4%. Risk factors that were associated with 1-year mortality included age (hazard ratio: 1.03 [95% CI, 1.02–1.04], P < 0.001), APACHE II score (1.03 [1.01–1.04], P < 0.001), mechanical ventilation (1.96 [1.60–2.41], P < 0.001), malignancy (2.31 [1.82–2.94], P < 0.001), readmission (1.65 [1.31–2.07], P < 0.001), emergency surgery (1.66 [1.18–2.34], P = 0.003), ICU admission due to medical causes (4.66 [3.68–5.91], P < 0.001), and non-traumatic diagnostic category (6.04 [1.50–24.38], P = 0.012).

Conclusions

The 1-year mortality rate was 13.4%. Old age, high APACHE II score, mechanical ventilation, malignancy, readmission, emergency surgery, ICU admission due to medical causes, and non-traumatic diagnostic category except metabolic/endocrinologic category were associated with 1-year mortality.