Intensivist coverage and critically ill COVID-19 patient outcomes: a population-based cohort study.

BACKGROUND: Trained intensivist staffing improves survival outcomes in critically ill patients at intensive care units. However, the impact on outcomes of critically ill patients with coronavirus disease 2019 has not yet been evaluated. We aimed to investigate whether trained intensivists affect outcomes among critically ill coronavirus disease 2019 patients in South Korean intensive care units. METHODS: Using a nationwide registration database in South Korea, we included adult patients admitted to the intensive care unit from October 8, 2020, to December 31, 2021, with a main diagnosis of coronavirus disease 2019. Critically ill patients admitted to intensive care units that employed trained intensivists were included in the intensivist group, whereas all other critically ill patients were assigned to the non-intensivist group. RESULTS: A total of 13,103 critically ill patients were included, with 2653 (20.2%) patients in the intensivist group and 10,450 (79.8%) patients in the non-intensivist group. In the covariate-adjusted multivariable logistic regression model, the intensivist group exhibited 28% lower in-hospital mortality than that of the non-intensivist group (odds ratio: 0.72; 95% confidence interval: 0.62, 0.83; P < 0.001). CONCLUSIONS: Trained intensivist coverage was associated with lower in-hospital mortality among critically ill coronavirus disease 2019 patients who required intensive care unit admission in South Korea.

Insomnia Disorder Among Coronavirus Disease Survivors: A South Korean Nationwide Cohort Study.

OBJECTIVE: We investigated the prevalence and associated factors of insomnia disorder among survivors of coronavirus disease of 2019 (COVID-19). METHODS: This population-based cohort study used data from the National Health Insurance Service COVID-19 cohort database from January 1 to June 4, 2020. COVID-19 patients were defined as individuals whose test confirmed that they were infected, regardless of the severity, and survivors were defined as individuals who recovered from the infection. RESULTS: A total of 299,968 individuals were included in the final analysis, and 6,934 were considered as COVID-19 survivors, while the control group comprised 292,764 individuals. In the multivariable model after covariate adjustment, COVID-19 survivors had a 3.33-fold higher prevalence of insomnia disorder than the control group (odds ratio [OR]: 3.33, 95% confidence interval [CI]: 2.98-3.73; p<0.001). In the sensitivity analysis, the COVID-19 survivors with no specific treatment and the survivors with specific treatment were associated with a 3.16-fold (OR: 3.16, 95% CI: 2.77-3.59; p<0.001) and 3.89-fold (OR: 3.89, 95% CI: 3.17-4.78; p<0.001) higher prevalence of insomnia disorder than the control group. CONCLUSION: In South Korea, 5.4% of COVID-19 survivors were diagnosed with insomnia disorder at 6 months follow-up. Thus, insomnia disorder is a public health issue for COVID-19 survivors.

Dementia Risk among Coronavirus Disease Survivors: A Nationwide Cohort Study in South Korea.

We aimed to investigate whether coronavirus disease (COVID-19) survivors were at a higher risk of dementia diagnosis compared to controls at 6 months follow-up. Data pertaining to the period between 1 January and 4 June 2020, were extracted from the National Health Insurance Service (NHIS)-COVID-19 database in South Korea. Data on adults (≥20 years old) with no history of dementia, obtained from the NHIS-COVID-19 database, were included in the study. The endpoint of this study was the development of dementia, which was evaluated from 1 January to 1 December 2020. A total of 306,577 adults were included in the analysis, comprising 7133 COVID-19 survivors and 299,444 individuals in the control group. Among the subjects, new-onset dementia diagnosed in 2020 was recorded in 1.2% (3546 of 306,577). In the covariate-adjusted multivariable Cox regression model, the incidence of dementia among COVID-19 survivors was 1.39-fold higher (hazard ratio: 1.39, 95% confidence interval: 1.05-1.85; p = 0.023) than that in the control group. At approximately 6 months of follow-up, COVID-19 survivors were at a higher risk of dementia compared to other populations in South Korea.

Prevalence of mental illness among COVID-19 survivors in South Korea: nationwide cohort.

BACKGROUND: Mental illness among survivors of coronavirus disease 2019 (COVID-2019) during the post-illness period is an emerging and important health issue. AIMS: We aimed to investigate the prevalence of mental illness and the associated factors for its development among COVID-2019 survivors. METHOD: From 1 January to 4 June 2020, data were extracted from the National Health Insurance Service COVID-19 database in South Korea. Patients with COVID-19 were defined as those whose test results indicated that they had contracted the infection, regardless of disease severity. COVID-19 survivors were defined as those who recovered from the infection. The primary end-point was the development of mental illness, which was evaluated between 1 January and 1 December 2020. RESULTS: A total 260 883 individuals were included in this study, and 2.36% (6148) were COVID-19 survivors. The COVID-19 survivors showed higher prevalence of mental illness than the control group (12.0% in the COVID-19 survivors v. 7.7% in the control group; odds ratio (OR) = 2.40, 95% CI 2.21-2.61, P < 0.001). Additionally, compared with the control group, the no specific treatment for COVID-19 group (OR = 2.23, 95% CI 2.03-2.45, P < 0.001) and specific treatment for COVID-19 group (OR = 3.27, 95% CI 2.77-3.87, P < 0.001) showed higher prevalence of mental illness among survivors. CONCLUSIONS: In South Korea, COVID-19 survivors had a higher risk of developing mental illness compared with the rest of the populations. Moreover, this trend was more evident in COVID-19 survivors who experienced specific treatment in the hospital.

Chronic respiratory disease and survival outcomes after extracorporeal membrane oxygenation.

BACKGROUND: Quality of life following extracorporeal membrane oxygenation (ECMO) therapy is an important health issue. We aimed to describe the characteristics of patients who developed chronic respiratory disease (CRD) following ECMO therapy, and investigate the association between newly diagnosed post-ECMO CRDs and 5-year all-cause mortality among ECMO survivors. METHODS: We analyzed data from the National Health Insurance Service in South Korea. All adult patients who underwent ECMO therapy in the intensive care unit between 2006 and 2014 were included. ECMO survivors were defined as those who survived for 365 days after ECMO therapy. Chronic obstructive pulmonary disease (COPD), asthma, interstitial lung disease, lung cancer, lung disease due to external agents, obstructive sleep apnea, and lung tuberculosis were considered as CRDs. RESULTS: A total of 3055 ECMO survivors were included, and 345 (11.3%) were newly diagnosed with CRDs 365 days after ECMO therapy. The prevalence of asthma was the highest at 6.1% (185). In the multivariate logistic regression, ECMO survivors who underwent ECMO therapy for acute respiratory distress syndrome (ARDS) or respiratory failure had a 2.00-fold increase in post-ECMO CRD (95% confidence interval [CI]: 1.39 to 2.89; P < 0.001). In the multivariate Cox regression, newly diagnosed post-ECMO CRD was associated with a 1.47-fold (95% CI: 1.17 to 1.86; P = 0.001) higher 5-year all-cause mortality. CONCLUSIONS: At 12 months after ECMO therapy, 11.3% of ECMO survivors were newly diagnosed with CRDs. Patients who underwent ECMO therapy for ARDS or respiratory failure were associated with a higher incidence of newly diagnosed post-ECMO CRD compared to those who underwent ECMO for other causes. Additionally, post-ECMO CRDs were associated with a higher 5-year all-cause mortality. Our results suggest that ECMO survivors with newly diagnosed post-ECMO CRD might be a high-risk group requiring dedicated interventions.

Musculoskeletal Disorders, Pain Medication, and in-Hospital Mortality among Patients with COVID-19 in South Korea: A Population-Based Cohort Study.

We aimed to investigate whether comorbid musculoskeletal disorders (MSD)s and pain medication use was associated with in-hospital mortality among patients with coronavirus disease 2019 (COVID-19). Adult patients (≥20 years old) with a positive COVID-19 diagnosis until 5 June 2020 were included in this study, based on the National Health Insurance COVID-19 database in South Korea. MSDs included osteoarthritis, neck pain, lower back pain, rheumatoid arthritis, and others, while pain medication included paracetamol, gabapentin, pregabalin, glucocorticoid, nonsteroidal anti-inflammatory drugs (NSAIDs), opioids (strong and weak opioids), and benzodiazepine. Primary endpoint was in-hospital mortality. A total of 7713 patients with COVID-19 were included, and in-hospital mortality was observed in 248 (3.2%) patients. In multivariate logistic regression analysis, no MSDs (p > 0.05) were significantly associated with in-hospital mortality. However, in-hospital mortality was 12.73 times higher in users of strong opioids (odds ratio: 12.73, 95% confidence interval: 2.44-16.64; p = 0.002), while use of paracetamol (p = 0.973), gabapentin or pregabalin (p = 0.424), glucocorticoid (p = 0.673), NSAIDs (p = 0.979), weak opioids (p = 0.876), and benzodiazepine (p = 0.324) was not associated with in-hospital mortality. In South Korea, underlying MSDs were not associated with increased in-hospital mortality among patients with COVID-19. However, use of strong opioids was significantly associated with increased in-hospital mortality among the patients.

Incidence and Mortality Associated with Cardiovascular Medication among Hypertensive COVID-19 Patients in South Korea.

PURPOSE: We aimed to investigate whether the use of cardiovascular drugs in coronavirus disease 2019 (COVID-19) patients with hypertension as a comorbidity has a significant effect on the incidence and associated mortality rate of COVID-19. MATERIALS AND METHODS: Data covering the period between January 1, 2020 and June 4, 2020 were extracted from The National Health Insurance Service-COVID-19 (NHIS-COVID-19) database in South Korea and analyzed as a population-based cohort study. RESULTS: A total of 101657 hypertensive adults aged 20 years or older were included for final analysis. Among them, 1889 patients (1.9%) were diagnosed with COVID-19 between January 1, 2020 and June 4, 2020, and hospital mortality occurred in 193 patients (10.2%). In a multivariable model, the use of beta-blockers was associated with an 18% lower incidence of COVID-19 [odds ratio (OR): 0.82, 95% confidence interval (CI): 0.69-0.98; p=0.029]. Among 1889 hypertensive patients diagnosed with COVID-19, the use of a calcium channel blocker (CCB) was associated with a 42% lower hospital mortality rate (OR: 0.58, 95% CI: 0.38-0.89; p=0.012). The use of other cardiovascular drugs was not associated with the incidence of COVID-19 or hospital mortality rate among COVID-19 patients. Similar results were observed in all 328374 adults in the NHIS-COVID-19 database, irrespective of the presence of hypertension. CONCLUSION: In South Korea, beta-blockers exhibited potential benefits in lowering the incidence of COVID-19 among hypertensive patients. Furthermore, CCBs may lower the hospital mortality rate among hypertensive COVID-19 patients. These findings were also applied to the general adult population, regardless of hypertension.

Statin Therapy and the Risk of COVID-19: A Cohort Study of the National Health Insurance Service in South Korea.

We aimed to investigate whether statin therapy is associated with the incidence of coronavirus disease 2019 (COVID-19) among the South Korean population. In addition, we examined whether statin therapy affects hospital mortality among COVID-19 patients. The National Health Insurance Service (NHIS)-COVID-19 database in South Korea was used for data extraction for this population-based cohort study. A total of 122,040 adult individuals, with 22,633 (18.5%) in the statin therapy group and 101,697 (91.5%) in the control group, were included in the analysis. Among them, 7780 (6.4%) individuals were diagnosed with COVID-19 and hospital mortality occurred in 251 (3.2%) COVID-19 cases. After propensity score matching, logistic regression analysis showed that the odds of developing COVID-19 were 35% lower in the statin therapy group than in the control group (odds ratio: 0.65, 95% confidence interval: 0.60 to 0.71; p < 0.001). Regarding hospital mortality among COVID-19 patients, the multivariable model indicated that there were no differences between the statin therapy and control groups (odds ratio: 0.74, 95% confidence interval: 0.52 to 1.05; p = 0.094). Statin therapy may have potential benefits for the prevention of COVID-19 in South Korea. However, we found that statin therapy does not affect the hospital mortality of patients who are diagnosed with COVID-19.

Metformin use and risk of COVID-19 among patients with type II diabetes mellitus: an NHIS-COVID-19 database cohort study.

AIMS: The relationship between metformin therapy and the risk of coronavirus disease (COVID-19) has not been reported among patients with type 2 diabetes mellitus (DM). We aimed to investigate whether metformin therapy was associated with the incidence of COVID-19 among type 2 DM patients in South Korea. METHODS: The National Health Insurance Service-COVID-19 cohort database, comprising COVID-19 patients from 1 January 2020 to 4 June 2020, was used for this study. Among them, adult patients with type 2 DM were included in this study. Metformin users were defined as those who had been prescribed continuous oral metformin for over a period of ≥ 90 days, and the control group was defined as all other patients. RESULTS: Overall, 27,493 patients with type 2 DM (7204, metformin user group; 20,289, control group) were included. After propensity score matching, 11,892 patients (5946 patients in each group) were included in the final analysis. In the logistic regression analysis, the odds of metformin users developing COVID-19 was 30% lower than that of the control group [odds ratio (OR): 0.70, 95% confidence interval (CI): 0.61-0.80; P < 0.001]. However, in the multivariate model, metformin use was not associated with hospital mortality when compared with that of the control group (OR: 1.26, 95% CI: 0.81-1.95; P = 0.301). CONCLUSIONS: Metformin therapy might have potential benefits for the prevention of COVID-19 among patients with type 2 DM in South Korea. However, it did not affect the hospital mortality of type 2 DM patients diagnosed with COVID-19.

Comparison of All-Cause Mortality Between Individuals With COVID-19 and Propensity Score-Matched Individuals Without COVID-19 in South Korea.

BACKGROUND: We compared all-cause mortality between individuals in South Korea with and without coronavirus disease 2019 (COVID-19) using propensity score (PS) matching. METHODS: This population-based cohort study used data from the National Health Insurance Service COVID-19 cohort database. In the database, we included individuals (COVID-19 patients, control population, and test-negative individuals) aged 20 years or older, regardless of hospitalization. The primary end point was all-cause mortality between January 1, 2020, and August 27, 2020. RESULTS: A total of 328 374 adults were included in the study: 7713 and 320 660 in the COVID-19 group and the control group. After PS matching, a total of 15 426 individuals (7713 per group) were included in the analysis. All-cause mortality was 3.2% (248/7713) and 1.6% (126/7713) in the COVID-19 group and the control group, respectively. In Cox regression analysis after PS matching, the risk of death in the COVID-19 group was twice as high (hazard ratio, 2.00; 95% CI, 1.61-2.48; P < .001) as that in the control group. Among patients aged ≥60 years, the COVID-19 group had a 2.32-fold higher all-cause mortality compared with the control group, while statistically significant differences were not observed in the age groups 20-39 years (P = .339) and 40-59 years (P = .562). CONCLUSIONS: In South Korea, all-cause mortality was twice as high among individuals with COVID-19 as among those with similar underlying risks, primarily because of the elevated COVID-19-associated mortality in those aged ≥60 years. Our results highlight the need for prevention of COVID-19 with respect to mortality as a public health outcome.

Socioeconomic disparity and the risk of contracting COVID-19 in South Korea: an NHIS-COVID-19 database cohort study.

BACKGROUND: The relationship between socioeconomic status and the risk of contracting coronavirus disease (COVID-19) remains controversial. We aimed to investigate whether socioeconomic status affected the risk of contracting COVID-19 in the South Korean population. METHODS: The NHIS-COVID-19 database cohort was used in this population-based study. We collected the data of COVID-19 patients who were diagnosed between January 1, 2020 and June 4, 2020 and those of the control population. The income levels of all individuals as of February 2020 were extracted, and study participants were classified into four groups based on quartiles: Q1 (the lowest) to Q4 (the highest). Data were statistically analyzed using multivariable logistic regression modeling. RESULTS: In total, 122,040 individuals-7669 and 114,371 individuals in the COVID-19 and control groups, respectively-were included in the final analysis. The multivariable logistic regression model showed that the Q1 group had a 1.19-fold higher risk of contracting COVID-19 than the Q4 group, whereas the Q2 and Q3 groups showed no significant differences. In the 20-39 years age group, compared with the Q4 group, the Q3 and Q2 groups showed 11 and 22% lower risks of contracting COVID-19, respectively. In the ≥60 years age group, compared with the Q4 group, the Q1, Q2, and Q3 groups showed a 1.39-, 1.29-, and 1.14-fold higher risks of COVID-19, respectively. CONCLUSIONS: Lower socioeconomic status was associated with a higher risk of contracting COVID-19 in South Korea. This association was more evident in the older population (age ≥ 60 years), whereas both lower and higher socioeconomic statuses were associated with higher risks of contracting COVID-19 in the young adult population (in the 20-39 year age group). Strategies for the prevention of COVID-19 should focus on individuals of lower socioeconomic status and on young adults of higher and lower socioeconomic status.

Impact of coronavirus disease-2019 on chronic respiratory disease in South Korea: an NHIS COVID-19 database cohort study.

BACKGROUND: The impact of underlying chronic respiratory diseases (CRDs) on the risk and mortality of patients with coronavirus disease 2019 (COVID-19) remains controversial. We aimed to investigate the effects of CRDs on the risk of COVID-19 and mortality among the population in South Korea. METHODS: The NHIS-COVID-19 database in South Korea was used for data extraction for this population-based cohort study. Chronic obstructive pulmonary disease (COPD), asthma, interstitial lung disease (ILD), lung cancer, lung disease due to external agents, obstructive sleep apnea (OSA), and tuberculosis of the lungs (TB) were considered CRDs. The primary endpoint was a diagnosis of COVID-19 between January 1st and June 4th, 2020; the secondary endpoint was hospital mortality of patients with COVID-19. Multivariable logistic regression modeling was used for statistical analysis. RESULTS: The final analysis included 122,040 individuals, 7669 (6.3%) were confirmed as COVID-19 until 4 June 2020, and 251 patients with COVID-19 (3.2%) passed away during hospitalization. Among total 122,040 individuals, 36,365 individuals were diagnosed with CRD between 2015 and 2019: COPD (4488, 3.6%), asthma (33,858, 27.2%), ILD (421, 0.3%), lung cancer (769, 0.6%), lung disease due to external agents (437, 0.4%), OSA (550, 0.4%), and TB (608, 0.5%). Among the CRDs, patients either with ILD or OSA had 1.63-fold (odds ratio [OR] 1.63, 95% confidence interval [CI] 1.17-2.26; P = 0.004) and 1.65-fold higher (OR 1.65, 95% CI 1.23-2.16; P < 0.001) incidence of COVID-19. In addition, among patients with COVID-19, the individuals with COPD and lung disease due to external agents had 1.56-fold (OR 1.56, 95% CI 1.06-2.2; P = 0.024) and 3.54-fold (OR 3.54, 95% CI 1.70-7.38; P < 0.001) higher risk of hospital mortality. CONCLUSIONS: Patients with OSA and ILD might have an increased risk of COVID-19. In addition, COPD and chronic lung disease due to external agents might be associated with a higher risk of mortality among patients with COVID-19. Our results suggest that prevention and management strategies should be carefully performed.