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.

We aimed to investigate the trends of intensive care unit (ICU) admissions in South Korea from 2010 to 2019. We included all adult patients (≥20 years old) who were admitted to the ICU during hospitalization from 2010 to 2019 in South Korea. There were 3,517,423 ICU admissions of 2,461,848 adult patients. Of the ICU admission cases, 66.8% (2,347,976/3,517,423) were surgery-associated admissions, and the rate of in-hospital mortality after ICU admission was 12.0% (422,155 patients). The most common diagnoses were diseases of the circulatory system (36.8%) and pneumonia (4%). The 30-day, 90-day, and 1-year mortality rates were 16.0%, 23.6%, and 33.3% in 2010, and these values slightly decreased by 2019 to 14.7%, 22.1%, and 31.7%, respectively. The proportions of continuous renal replacement therapy (CRRT) use and extracorporeal membrane oxygenation (ECMO) support were 2.0% and 0.3% in 2010, and these values gradually increased by 2019 to 4.7% and 0.8%, respectively. Although the age and cost of hospitalization among critically ill patients who were admitted to the ICU increased from 2010 to 2019, the mortality rate decreased slightly. Moreover, the proportions of ECMO support and CRRT use had increased in our South Korean cohort.

We aimed to examine whether preoperative psychiatric morbidities affect 30-day postoperative mortality. Using a nationwide registration database in South Korea, the study included all patients who underwent curative cancer surgery from 1 January 2002 to 31 December 2019. Patients underwent surgery for breast, laryngeal, lung, thyroid, gastric, colorectal, esophageal, liver, pancreatic, kidney, bladder, testicular, prostate, vulvar, uterine, or brain cancer. Depression, anxiety disorder, substance abuse, and post-traumatic stress disorder were considered preoperative psychiatric morbidities. Among the 944,794 patients in the final analysis, 5490 (0.6%) died within 30 days of the surgery, and 24,370 (2.6%) had preoperative psychiatric morbidities. Multivariable logistic regression analysis showed that preoperative psychiatric morbidities were associated with a higher (adjusted odds ratio [aOR]: 1.23; 95% confidence interval [CI]: 1.09, 1.39; p = 0.001) 30-day mortality rate than the rate noted for patients without preoperative psychiatric morbidities. This association was significant in the breast (aOR: 3.31, 95% CI: 1.36, 8.07; p = 0.009), lung (aOR: 1.54, 95% CI: 1.19, 2.01; p = 0.001), and kidney (aOR: 1.87, 95% CI: 1.06, 3.31; p = 0.03) cancer groups in the subgroup analyses. In South Korea, preoperative psychiatric morbidities are considered to be associated with increased 30-day postoperative mortality.