Background: The World Health Organization has declared the end of the coronavirus disease 2019 (COVID-19) public health emergency. However, this did not indicate the end of COVID-19. Several months after the infection, numerous patients complain of respiratory or nonspecific symptoms; this condition is called long COVID. Even patients with mild COVID-19 can experience long COVID, thus the burden of long COVID remains considerable. Therefore, we conducted this study to comprehensively analyze the effects of long COVID using multi-faceted assessments. Materials and Methods: We conducted a prospective cohort study involving patients diagnosed with COVID-19 between February 2020 and September 2021 in six tertiary hospitals in Korea. Patients were followed up at 1, 3, 6, 12, 18, and 24 months after discharge. Long COVID was defined as the persistence of three or more COVID-19-related symptoms. The primary outcome of this study was the prevalence of long COVID after the period of COVID-19. Results: During the study period, 290 patients were enrolled. Among them, 54.5 and 34.6% experienced long COVID within 6 months and after more than 18 months, respectively. Several patients showed abnormal results when tested for post-traumatic stress disorder (17.4%) and anxiety (31.9%) after 18 months. In patients who underwent follow-up chest computed tomography 18 months after COVID-19, abnormal findings remained at 51.9%. Males (odds ratio [OR], 0.17; 95% confidence interval [CI], 0.05–0.53; P=0.004) and elderly (OR, 1.04; 95% CI, 1.00–1.09; P=0.04) showed a significant association with long COVID after 12–18 months in a multivariable logistic regression analysis. Conclusion Many patients still showed long COVID after 18 months post SARS-CoV-2 infection. When managing these patients, the assessment of multiple aspects is necessary.

Background: The World Health Organization has declared the end of the coronavirus disease 2019 (COVID-19) public health emergency. However, this did not indicate the end of COVID-19. Several months after the infection, numerous patients complain of respiratory or nonspecific symptoms; this condition is called long COVID. Even patients with mild COVID-19 can experience long COVID, thus the burden of long COVID remains considerable. Therefore, we conducted this study to comprehensively analyze the effects of long COVID using multi-faceted assessments. Materials and Methods: We conducted a prospective cohort study involving patients diagnosed with COVID-19 between February 2020 and September 2021 in six tertiary hospitals in Korea. Patients were followed up at 1, 3, 6, 12, 18, and 24 months after discharge. Long COVID was defined as the persistence of three or more COVID-19-related symptoms. The primary outcome of this study was the prevalence of long COVID after the period of COVID-19. Results: During the study period, 290 patients were enrolled. Among them, 54.5 and 34.6% experienced long COVID within 6 months and after more than 18 months, respectively. Several patients showed abnormal results when tested for post-traumatic stress disorder (17.4%) and anxiety (31.9%) after 18 months. In patients who underwent follow-up chest computed tomography 18 months after COVID-19, abnormal findings remained at 51.9%. Males (odds ratio [OR], 0.17; 95% confidence interval [CI], 0.05–0.53; P=0.004) and elderly (OR, 1.04; 95% CI, 1.00–1.09; P=0.04) showed a significant association with long COVID after 12–18 months in a multivariable logistic regression analysis. Conclusion Many patients still showed long COVID after 18 months post SARS-CoV-2 infection. When managing these patients, the assessment of multiple aspects is necessary.

Background: The World Health Organization has declared the end of the coronavirus disease 2019 (COVID-19) public health emergency. However, this did not indicate the end of COVID-19. Several months after the infection, numerous patients complain of respiratory or nonspecific symptoms; this condition is called long COVID. Even patients with mild COVID-19 can experience long COVID, thus the burden of long COVID remains considerable. Therefore, we conducted this study to comprehensively analyze the effects of long COVID using multi-faceted assessments. Materials and Methods: We conducted a prospective cohort study involving patients diagnosed with COVID-19 between February 2020 and September 2021 in six tertiary hospitals in Korea. Patients were followed up at 1, 3, 6, 12, 18, and 24 months after discharge. Long COVID was defined as the persistence of three or more COVID-19-related symptoms. The primary outcome of this study was the prevalence of long COVID after the period of COVID-19. Results: During the study period, 290 patients were enrolled. Among them, 54.5 and 34.6% experienced long COVID within 6 months and after more than 18 months, respectively. Several patients showed abnormal results when tested for post-traumatic stress disorder (17.4%) and anxiety (31.9%) after 18 months. In patients who underwent follow-up chest computed tomography 18 months after COVID-19, abnormal findings remained at 51.9%. Males (odds ratio [OR], 0.17; 95% confidence interval [CI], 0.05–0.53; P=0.004) and elderly (OR, 1.04; 95% CI, 1.00–1.09; P=0.04) showed a significant association with long COVID after 12–18 months in a multivariable logistic regression analysis. Conclusion Many patients still showed long COVID after 18 months post SARS-CoV-2 infection. When managing these patients, the assessment of multiple aspects is necessary.

OBJECTIVES: Chronic kidney disease (CKD) is a prevalent health issue that causes the irreversible loss of functioning nephrons, end-stage renal disease, cardiovascular disease, and premature mortality. Hypertension is the leading cause of CKD. However, the effect of long-term blood pressure (BP) changes on the development of CKD is still unknown. Therefore, the current study investigated the association between BP trajectory and the future development of CKD. METHODS: In this study, 246,874 individuals aged ≥40 years who underwent health examinations during the screening period (2002-2009) were evaluated. The systolic blood pressure (SBP) trajectory was determined using latent-class mixture modeling. New-onset CKD was identified during the follow-up period (2010-2019). The association between SBP trajectories and new-onset CKD was assessed. RESULTS: In total, 111,900 adults (53,420 females, 51.9±6.4 years old) presented with 2 SBP trajectory classes: class 1 (n=66,935) and class 2 (n=44,965). During the follow-up period, patients with SBP trajectory class 2 had an approximately 2.1-fold increased risk of developing CKD (unadjusted hazard ratio [HR], 2.11; 95% confidence interval [CI], 1.99 to 2.25; p<0.001). In the multivariate analysis adjusted for other significant variables, SBP trajectory class 2 was significantly associated with CKD in males (HR, 1.09; 95% CI, 1.00 to 1.19; p=0.037), but not in females (HR, 1.06; 95% CI, 0.95 to 1.18; p=0.321). CONCLUSIONS An elevated longitudinal BP was associated with a higher incidence of CKD in male participants aged ≥40 years. Nevertheless, further studies are needed to validate the clinical significance of an elevated SBP trajectory on CKD development.

OBJECTIVES: Chronic kidney disease (CKD) is a prevalent health issue that causes the irreversible loss of functioning nephrons, end-stage renal disease, cardiovascular disease, and premature mortality. Hypertension is the leading cause of CKD. However, the effect of long-term blood pressure (BP) changes on the development of CKD is still unknown. Therefore, the current study investigated the association between BP trajectory and the future development of CKD. METHODS: In this study, 246,874 individuals aged ≥40 years who underwent health examinations during the screening period (2002-2009) were evaluated. The systolic blood pressure (SBP) trajectory was determined using latent-class mixture modeling. New-onset CKD was identified during the follow-up period (2010-2019). The association between SBP trajectories and new-onset CKD was assessed. RESULTS: In total, 111,900 adults (53,420 females, 51.9±6.4 years old) presented with 2 SBP trajectory classes: class 1 (n=66,935) and class 2 (n=44,965). During the follow-up period, patients with SBP trajectory class 2 had an approximately 2.1-fold increased risk of developing CKD (unadjusted hazard ratio [HR], 2.11; 95% confidence interval [CI], 1.99 to 2.25; p<0.001). In the multivariate analysis adjusted for other significant variables, SBP trajectory class 2 was significantly associated with CKD in males (HR, 1.09; 95% CI, 1.00 to 1.19; p=0.037), but not in females (HR, 1.06; 95% CI, 0.95 to 1.18; p=0.321). CONCLUSIONS An elevated longitudinal BP was associated with a higher incidence of CKD in male participants aged ≥40 years. Nevertheless, further studies are needed to validate the clinical significance of an elevated SBP trajectory on CKD development.

OBJECTIVES: Chronic kidney disease (CKD) is a prevalent health issue that causes the irreversible loss of functioning nephrons, end-stage renal disease, cardiovascular disease, and premature mortality. Hypertension is the leading cause of CKD. However, the effect of long-term blood pressure (BP) changes on the development of CKD is still unknown. Therefore, the current study investigated the association between BP trajectory and the future development of CKD. METHODS: In this study, 246,874 individuals aged ≥40 years who underwent health examinations during the screening period (2002-2009) were evaluated. The systolic blood pressure (SBP) trajectory was determined using latent-class mixture modeling. New-onset CKD was identified during the follow-up period (2010-2019). The association between SBP trajectories and new-onset CKD was assessed. RESULTS: In total, 111,900 adults (53,420 females, 51.9±6.4 years old) presented with 2 SBP trajectory classes: class 1 (n=66,935) and class 2 (n=44,965). During the follow-up period, patients with SBP trajectory class 2 had an approximately 2.1-fold increased risk of developing CKD (unadjusted hazard ratio [HR], 2.11; 95% confidence interval [CI], 1.99 to 2.25; p<0.001). In the multivariate analysis adjusted for other significant variables, SBP trajectory class 2 was significantly associated with CKD in males (HR, 1.09; 95% CI, 1.00 to 1.19; p=0.037), but not in females (HR, 1.06; 95% CI, 0.95 to 1.18; p=0.321). CONCLUSIONS An elevated longitudinal BP was associated with a higher incidence of CKD in male participants aged ≥40 years. Nevertheless, further studies are needed to validate the clinical significance of an elevated SBP trajectory on CKD development.

OBJECTIVES: Chronic kidney disease (CKD) is a prevalent health issue that causes the irreversible loss of functioning nephrons, end-stage renal disease, cardiovascular disease, and premature mortality. Hypertension is the leading cause of CKD. However, the effect of long-term blood pressure (BP) changes on the development of CKD is still unknown. Therefore, the current study investigated the association between BP trajectory and the future development of CKD. METHODS: In this study, 246,874 individuals aged ≥40 years who underwent health examinations during the screening period (2002-2009) were evaluated. The systolic blood pressure (SBP) trajectory was determined using latent-class mixture modeling. New-onset CKD was identified during the follow-up period (2010-2019). The association between SBP trajectories and new-onset CKD was assessed. RESULTS: In total, 111,900 adults (53,420 females, 51.9±6.4 years old) presented with 2 SBP trajectory classes: class 1 (n=66,935) and class 2 (n=44,965). During the follow-up period, patients with SBP trajectory class 2 had an approximately 2.1-fold increased risk of developing CKD (unadjusted hazard ratio [HR], 2.11; 95% confidence interval [CI], 1.99 to 2.25; p<0.001). In the multivariate analysis adjusted for other significant variables, SBP trajectory class 2 was significantly associated with CKD in males (HR, 1.09; 95% CI, 1.00 to 1.19; p=0.037), but not in females (HR, 1.06; 95% CI, 0.95 to 1.18; p=0.321). CONCLUSIONS An elevated longitudinal BP was associated with a higher incidence of CKD in male participants aged ≥40 years. Nevertheless, further studies are needed to validate the clinical significance of an elevated SBP trajectory on CKD development.

Background: Since the emergence of hypervirulent strains of Clostridioides difficile, the incidence of C. difficile infections (CDI) has increased significantly. Methods: To assess the incidence of CDI in Korea, we conducted a prospective multicentre observational study from October 2020 to October 2021. Additionally, we calculated the incidence of CDI from mass data obtained from the Health Insurance Review and Assessment Service (HIRA) from 2008 to 2020. Results: In the prospective study with active surveillance, 30,212 patients had diarrhoea and 907 patients were diagnosed with CDI over 1,288,571 patient-days and 193,264 admissions in 18 participating hospitals during 3 months of study period; the CDI per 10,000 patientdays was 7.04 and the CDI per 1,000 admission was 4.69. The incidence of CDI was higher in general hospitals than in tertiary hospitals: 6.38 per 10,000 patient-days (range: 3.25–12.05) and 4.18 per 1,000 admissions (range: 1.92–8.59) in 11 tertiary hospitals, vs. 9.45 per 10,000 patient-days (range: 5.68–13.90) and 6.73 per 1,000 admissions (range: 3.18–15.85) in seven general hospitals. With regard to HIRA data, the incidence of CDI in all hospitals has been increasing over the 13-year-period: from 0.3 to 1.8 per 10,000 patient-days, 0.3 to 1.6 per 1,000 admissions, and 6.9 to 56.9 per 100,000 population, respectively. Conclusion The incidence of CDI in Korea has been gradually increasing, and its recent value is as high as that in the United State and Europe. CDI is underestimated, particularly in general hospitals in Korea.

Subclinical hypothyroidism (SCH), characterized by elevated serum thyroid-stimulating hormone (TSH) levels and normal free thyroxine levels, usually presents without symptoms, and is often discovered incidentally during routine blood test. The Task Force of the Korean Thyroid Association Committee of Clinical Practice Guidelines has established a guideline to evaluate and manage SCH; the guideline emphasizes the implementation of diagnostic criteria based on the TSH reference range for Koreans and focuses on the proven health benefits of levothyroxine (LT4) treatment. Based on the Korea National Health and Nutrition Examination Survey (2013-2015), serum TSH level of 6.8 mIU/L is considered the reference value for SCH. SCH can be categorized as mild (TSH 6.8-10.0 mIU/L) or severe (TSH ＞10.0 mIU/L), and patients are classified as adults (age ＜70 years) or elderly patients (age ≥70years) depending on the health effects of LT4 treatment. An initial increase in serum TSH levels should be reassessed with a subsequent measurement, along with the thyroid peroxidase antibody test, preferably 2-3 months after the initial evaluation. Usually, LT4 treatment is not recommended for mild SCH in adults; however, treatment is necessary for severe SCH in patients with underlying coronary artery disease or heart failure and can be considered for coexisting dyslipidemia. LT4 treatment is not recommended for mild or even severe SCH in elderly patients, in general. Patients with SCH who receive LT4 treatment, the LT4 dosage should be personalized, and serum TSH levels should be monitored to ensure optimal LT4 dosage (dosage that is neither excessive nor insufficient). Patients with SCH who do not receive LT4 treatment require periodic follow-up at appropriate testing intervals determined by disease severity. The guideline also provides several educational points applicable in clinical settings.