Effect of the Frequency of Rehabilitation Treatments on the Long-Term Mortality of Stroke Survivors with Mild-to-Moderate Disabilities under the Korean National Health Insurance Service System.

Given the increase in stroke-related social costs, studies on survival and functional prognosis after stroke are urgently needed. Therefore, we investigated the relationship between the frequency of rehabilitation treatments in the acute and subacute phases of stroke and the long-term mortality of stroke survivors with mild-to-moderate disabilities. We performed a retrospective cohort study using data from the Korean National Health Insurance Service database. Our final cohort included 733 patients with national disability registration grades 4-6. The number of special rehabilitation treatment claim codes was used as a proxy for the frequency of rehabilitation treatments. Furthermore, we categorized the rehabilitation frequencies within 24 months of stroke onset as 1-50, 51-200, 201-400, and >400. The dependent variable was all-cause mortality, and it was evaluated from 24 to 84 months after stroke onset. Severe disability was associated with a lower long-term mortality rate in the chronic phase (p < 0.001). In the Cox regression analysis, severe disability, older age, male sex, and chronic kidney disease were independent risk factors for long-term mortality in patients with stroke and mild-to-moderate disabilities. However, the frequency of acute/subacute rehabilitation treatments did not significantly improve long-term mortality. Our results suggest that the association between rehabilitation frequency and lower long-term mortality for patients with mild-to-moderate stroke was inconclusive. Therefore, further study is needed to determine a better-customized rehabilitation treatment system for these patients.

Trends in treatment patterns and survival outcomes in pancreatic cancer: A nationwide population-based study in Korea.

BACKGROUND: The treatment of pancreatic cancer has evolved; however, real-world data on treatment trends remain scarce. This study investigated treatment patterns for pancreatic cancer and patient survival using a nationwide population-based study in Korea. METHODS: Using the National Health Insurance database, data from 78,920 patients diagnosed with pancreatic cancer in Korea between 2006 and 2019 were extracted. Treatment patterns and survival by age group and year of diagnosis were examined. RESULTS: Primary treatment was delivered as follows: 16,562 patients (21.0%) underwent surgery, 20,998 patients (26.6%) received chemotherapy, 1332 patients (1.7%) received chemoradiotherapy, and 40,040 patients (50.7%) received supportive care only. The proportion of patients undergoing surgery or chemotherapy increased gradually in all age groups over time. The commonly used anti-cancer drugs have changed from gemcitabine±erlotinib to gemcitabine+nab-paclitaxel and FOLFIRINOX. Survival improved mainly in patients who underwent surgery or chemotherapy. Median overall survival for all patients improved from 5.5 months in 2006-2008 to 9.8 months in 2018-2019, with greater improvement observed in younger age groups: 8.8-18.8 months, age ≤59 years, 6.8-14.6 months, age 60-69 years, 4.2-8.3 months, age 70-79 years and 2.4-3.4 months, age ≥80 years (all p < 0.0001). CONCLUSIONS: An increase in the rates of surgery and chemotherapy for pancreatic cancer was observed. Survival rates for pancreatic cancer have generally improved over the past decade and are greater in patients undergoing surgery or chemotherapy and in younger age groups.

Risk of pancreatic cancer after acute pancreatitis: A population-based matched cohort study.

BACKGROUND: We investigated the short- and long-term risks of pancreatic cancer after the diagnosis of acute pancreatitis. METHODS: This population-based matched-cohort study used data from the Korean National Health Insurance Service database. Patients with acute pancreatitis (n = 25,488) were matched with the control group (n = 127,440) based on age, sex, body mass index, smoking status, and diabetes. We estimated the hazard ratios for developing pancreatic cancer in both groups using Cox regression analysis. RESULTS: During a median follow-up of 5.4 years, pancreatic cancer developed in 479 patients (1.9%) in the acute pancreatitis group and 317 patients (0.2%) in the control group. Compared with the control group, the risk of pancreatic cancer in the acute pancreatitis group was very high within the first 2 years, which gradually decreased over time. The hazard ratio for the risk of developing pancreatitis was 8.46 (95% confidence interval, 5.57-12.84) at 1-2 years, and then decreased to 3.62 (95% confidence interval, 2.26-4.91) at 2-4 years. However, even after 8-10 years, the hazard ratio was still statistically significantly increased to 2.80 (95% confidence interval, 1.42-5.53). After 10 years, there was no significant difference in the risk of pancreatic cancer between the two groups. CONCLUSIONS: The risk of pancreatic cancer increases rapidly after acute pancreatitis diagnosis, gradually declines after 2 years, and remains elevated for up to 10 years. Further studies are needed to determine the long-term effects of acute pancreatitis on the risk of pancreatic cancer.

Age at Mortality in Patients with Type 2 Diabetes Who Underwent Kidney Transplantation: An Analysis of Data from the Korean National Health Insurance and Statistical Information Service, 2006 to 2018.

BACKGROUND: Although the clinical outcomes of diabetes have improved, diabetes remains the principal cause of end-stage renal disease. The aim of the study is to investigate whether mortality trends in individuals with type 2 diabetes and kidney transplantation (KT) have changed. METHODS: This study analyzed data from the National Health Insurance Service claims database linked to death records from the National Statistical Information Service in Korea. Information from a total of 2521 deaths of KT recipients was collected from 2006 to 2018. RESULTS: The age at death of KT recipients increased from 57.4 years in 2006 to 65.2 years in 2018, with a mean change of +0.65 years/year (p < 0.001). The overall age at death increased by 0.55 and 0.66 years/year in the type 2 diabetes and non-diabetes populations, respectively. The age at death was significantly higher in the type 2 diabetes group, and was maintained during the study period. The proportion of death due to malignancy and cerebrovascular and heart disease was maintained, that due to type 2 diabetes decreased and that due to pneumonia increased. Neither diabetes nor hypertension determined the age at death, and the age at KT was the most prominent factor affecting age at death in KT recipients. CONCLUSIONS: The age at death in KT recipients increased over the 12 years between 2006 and 2018, with similar trends in the type 2 diabetes and non-diabetes groups. The age at KT was higher in patients with type 2 diabetes, and was the main contributor to the age at death in KT recipients.

Chronic Phase Survival Rate in Stroke Patients With Severe Functional Limitations According to the Frequency of Rehabilitation Treatment.

OBJECTIVE: To investigate the chronic phase survival rate according to the frequency of rehabilitation treatment in the acute and subacute phases in stroke patients with severe functional limitations. DESIGN: A retrospective longitudinal cohort study. SETTING: Population-based study using the Korean National Health Insurance Database from 2007 to 2018. PARTICIPANTS: We enrolled 593 patients who experienced stroke in 2009 with national disability registration (NDR) grade of 3 or less (N=593). INTERVENTION: Not applicable. MAIN OUTCOME MEASURES: The frequencies of rehabilitation treatment within 24 months after stroke were categorized into none, 1-50, 51-200, 201-400, and >400 treatments based on requests made to the Health Insurance Review and Assessment Service. As a dependent variable, we assessed all-cause mortality from 24 to 120 months after stroke. RESULTS: The study enrolled 283 patients in NDR grade 1 (the most severe), 158 in grade 2, and 152 in grade 3. Groups with more severe functional limitations showed a lower chronic phase survival rate (P<.001). The groups with higher frequencies of rehabilitation treatment in the acute and subacute phases showed a higher chronic phase survival rate (P<.001). In the Cox regression analysis, a higher degree of functional limitation, lower frequency of rehabilitation treatment, older age, male sex, and chronic kidney disease were independent risk factors for chronic phase mortality in stroke patients with severe functional limitations. CONCLUSIONS: A high frequency of rehabilitation treatment in the acute and subacute phases was associated with the long-term survival of stroke patients with severe functional limitations.

Cardiovascular and cerebrovascular-associated mortality in patients with preceding bronchiectasis exacerbation.

BACKGROUND: Bronchiectasis is associated with an increased incidence of atherosclerotic cardiovascular disease (ASCaVD) and atherosclerotic cerebrovascular disease (ASCeVD). Its effect on associated mortality is unclear. OBJECTIVES: This study investigated the effects of bronchiectasis exacerbation prior to ASCaVD or ASCeVD events on mortality in patients with bronchiectasis using a large population-based database. METHODS: A retrospective cohort of patients with bronchiectasis who experienced ASCaVD (n = 1066) or ASCeVD (n = 825) was studied for the first time using a nationwide population-based database (National Health Insurance Service-National Sample Cohort, Korea, 2002-2015). We classified each cohort according to the presence of moderate bronchiectasis exacerbation within 1 year before the ASCaVD or ASCeVD event. We evaluated 90-day, 1-year, and all-cause mortalities risk. RESULTS: Within 1 year before the index ASCaVD or ASCeVD event, 149 (13.9%) and 112 (13.6%) patients with bronchiectasis experienced moderate exacerbation(s), respectively. Mild exacerbations did not different in frequency between the survivors and nonsurvivors. In both cohorts, more nonsurvivors experienced moderate exacerbations than survivors. The odds ratios of 90-day and 1-year mortalities and hazard ratios of all-cause mortalities on experiencing moderate exacerbations were 2.27 [95% confidence interval (CI) = 1.26-4.10], 3.30 (95% CI = 2.03-5.38), and 1.78 (95% CI = 1.35-2.34) in the bronchiectasis-ASCaVD cohort and 1.73 (95% CI = 0.94-3.19), 1.79 (95% CI = 1.07-3.00), and 1.47 (95% CI = 1.10-1.95), in the bronchiectasis-ASCeVD cohort. CONCLUSION: Hospitalization or emergency room visit for bronchiectasis exacerbation within 1 year before ASCaVD or ASCeVD is associated with an increased ASCaVD- or ASCeVD-associated mortality.

Effects of Socioeconomic Status and Residence Areas on Long-Term Survival in Patients With Early-Onset Dementia: The Korean National Health Insurance Service Database Study.

BACKGROUND: Early-onset dementia (EOD) is still insufficiently considered for healthcare policies. We investigated the effect of socio-environmental factors on the long-term survival of patients with EOD. METHODS: This retrospective cohort study utilized the Korean National Health Insurance Database from 2007 to 2018. We enrolled 3,825 patients aged 40 to 65 years old with all types of dementia newly diagnosed in 2009 as EOD cases. We defined socioeconomic status using the national health insurance premium (NHIP) levels. Residential areas were classified into capital, metropolitan, city, and county levels. All-cause mortality was the primary outcome. Kaplan-Meier curves and log-rank tests were employed. Further, Cox-proportional hazards models were established. RESULTS: The mean survival of the fourth NHIP level group was 96.31 ± 1.20 months, whereas that of the medical-aid group was 85.53 ± 1.30 months (P < 0.001). The patients living in the capital had a mean survival of 95.73 ± 1.34 months, whereas those living in the county had 89.66 ± 1.75 months (P = 0.035). In the Cox-proportional hazards model, the medical-aid (adjusted hazard ratio [aHR], 1.67; P < 0.001), first NHIP level (aHR, 1.26; P = 0.012), and second NHIP level (aHR, 1.26; P = 0.008) groups were significantly associated with a higher long-term mortality risk. The capital residents exhibited a significantly lower long-term mortality risk than did the county residents (aHR, 0.82; P = 0.041). CONCLUSION: Socioeconomic status and residential area are associated with long-term survival in patients with EOD. This study provides a rational basis for establishing a healthcare policy for patients with EOD.

Incidence of Acute Endophthalmitis after Intravitreal Antivascular Endothelial Growth Factor Injection in Age-related Macular Degeneration.

PURPOSE: Antivascular endothelial growth factor (anti-VEGF) agents are routinely intravitreously injected to treat neovascular age-related macular degeneration (AMD). Postoperative endophthalmitis, a side effect after intravitreal anti-VEGF injection, has been reported to have a low incidence but may threaten vision. In this study, we aimed to analyze the incidence of acute endophthalmitis after intravitreal anti-VEGF injection and associated risk factors in patients with neovascular AMD in South Korea. METHODS: Using the health claims data recorded in the Korean National Health Insurance System database, we identified newly developed neovascular AMD cases from 2010 through 2019. Acute endophthalmitis was defined as a case of invasive treatment for accompanying symptoms. All statistical analyses were performed with a significance level p < 0.05. To find risk factors, we used univariate and multivariable Poisson regression. RESULTS: The overall incidence of acute endophthalmitis was 0.019% (p = 0.21) during the 10-year period: 0.025% for aflibercept injection and 0.014% for ranibizumab injection. The incidence was higher in metropolitan city residents than in Seoul (incidence rate ratio [IRR], 1.96; 95% confidence interval [CI], 1.02-3.79; p = 0.04) and was higher for aflibercept injections than for ranibizumab injections (IRR, 1.82; 95% CI, 1.17-2.82; p = 0.01). However, in multivariate analysis, only aflibercept injections showed a significant effect on the incidence of acute endophthalmitis (IRR, 1.80; 95% CI, 1.16-2.79; p = 0.01). CONCLUSIONS: The incidence of acute endophthalmitis after intravitreal anti-VEGF injections was generally low, and aflibercept was revealed as a significant risk factor.

Improvement in Age at Mortality and Changes in Causes of Death in the Population with Diabetes: An Analysis of Data from the Korean National Health Insurance and Statistical Information Service, 2006 to 2018.

BACKGRUOUND: Diabetes is a leading cause of death that is responsible for 1.6 million annual deaths worldwide. However, the life expectancy and age at death of people with diabetes have been a matter of debate. METHODS: The National Health Insurance Service claims database, merged with death records from the National Statistical Information Service in Korea from 2006 to 2018, was analyzed. RESULTS: In total, 1,432,567 deaths were collected. The overall age at death increased by 0.44 and 0.26 year/year in the diabetes and control populations, respectively. The disparity in the mean age at death between the diabetes and control populations narrowed from 5.2 years in 2006 to 3.0 years in 2018 (p<0.001). In a subgroup analysis according to the presence of comorbid diseases, the number and proportion of deaths remained steady in the group with diabetes only, but steadily increased in the groups with diabetes combined with dyslipidemia and/or hypertension. Compared to the control population, the increase in the mean death age was higher in the population with diabetes. This trend was more prominent in the groups with dyslipidemia and/or hypertension than in the diabetes only group. Deaths from vascular disease and diabetes decreased, whereas deaths from cancer and pneumonia increased. The decline in the proportion of deaths from vascular disease was greater in the diabetes groups with hypertension and/or dyslipidemia than in the control population. CONCLUSION: The age at death in the population with diabetes increased more steeply and reached a comparable level to those without diabetes.

The effects of socioeconomic and geographic factors on chronic phase long-term survival after stroke in South Korea.

The stroke incidence has increased rapidly in South Korea, calling for a national-wide system for long-term stroke management. We investigated the effects of socioeconomic status (SES) and geographic factors on chronic phase survival after stroke. We retrospectively enrolled 6994 patients who experienced a stroke event in 2009 from the Korean National Health Insurance database. We followed them up from 24 to 120 months after stroke onset. The endpoint was all-cause mortality. We defined SES using a medical-aid group and four groups divided by health insurance premium quartiles. Geographic factors were defined using Model 1 (capital, metropolitan, city, and county) and Model 2 (with or without university hospitals). The higher the insurance premium, the higher the survival rate tended to be (P < 0.001). The patient survival rate was highest in the capital city and lowest at the county level (P < 0.001). Regions with a university hospital(s) showed a higher survival rate (P = 0.006). Cox regression revealed that the medical-aid group was identified as an independent risk factor for chronic phase mortality. Further, NHIP level had a more significant effect than geographic factors on chronic stroke mortality. From these results, long-term nationwide efforts to reduce inter-regional as well as SES discrepancies affecting stroke management are needed.

Declined incidence of patients treated for vision-threatening diabetic retinopathy in South Korea: a 12-year nationwide population-based study.

PURPOSE: To determine the age- and sex-specific annual incidence rates of patients treated for VTDR and the factors associated with increased treatment rates in patients with type 2 diabetes mellitus (T2DM) in South Korea. METHODS: This was a nationwide, retrospective, 12-year, population-based study. Patients aged over 30 years who were diagnosed with T2DM between 2006 and 2017 were included in this study. We evaluated the national health claims data acquired from the Korean National Health Insurance Service database. Main outcome measures were the annual incidence rates of patients treated for VTDR and the associated risk factors. RESULTS: The age-adjusted annual incidence rate of patients treated for VTDR significantly decreased from 10.05 per 1000 T2DM patients in 2006 to 6.11 in 2017 (ß = - 0.3192, P < 0.0001). The sex-adjusted annual incidence rate also significantly decreased in both men (ß = - 0.2861, P < 0.0001) and women (ß = - 0.3666, P < 0.0001). Cox hazard analysis showed that factors such as insulin use, young age, chronic kidney disease and male sex were significantly associated with increased rate of treatments for VTDR. In addition, the risk was lower for rural than for metropolitan residents. CONCLUSIONS: Despite the increase in the number of T2DM patients in South Korea, the incidence rate of patients treated for VTDR decreases with early diagnosis and appropriate treatment. Therefore, it is important to detect and manage high-risk groups early to prevent visual impairment due to VTDR.

Association between Inhaled Corticosteroid Use and SARS-CoV-2 Infection: A Nationwide Population-Based Study in South Korea.

BACKGROUND: Although it is known that inhaled corticosteroid (ICS) use may increase the risk of respiratory infection, its influence on the risk of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection remains unknown. Thus, the aim of this study was to investigate the association between ICS use and the positivity of SARS-CoV-2 infection among patients with chronic respiratory diseases. METHODS: Nationwide data of 44,968 individuals with chronic respiratory diseases tested for SARS-CoV-2 until May 15, 2021 were obtained from the Ministry of Health and Welfare and Health Insurance Review and Assessment Service in Korea. The positivity of SARS-CoV-2 infection was retrospectively analysed according to the prescription, type, and dose of ICS taken one year before SARS-CoV-2 test. RESULTS: Among 44,968 individuals tested, 931 (2.1%) were positive for SARS-CoV-2. A total of 7,019 patients (15.6%) were prescribed ICS one year prior to being tested for SARS-CoV-2. Low, medium, and high doses of ICS were prescribed in 7.5%, 1.6%, and 6.5% of total cases, respectively. Among types of ICS, budesonide, fluticasone, beclomethasone, and ciclesonide were prescribed in 3.7%, 8.9%, 2.3%, and 0.6% of total cases, respectively. A multivariate analysis showed no significant increase in infection with ICS use (odds ratio, 0.84; 95% confidence interval, 0.66-1.03). Moreover, there were no associations between the positivity of infection and the dose or type of ICS prescribed. CONCLUSION: Prior ICS use did not increase the positivity for SARS-CoV-2 infection. Moreover, different doses or types of ICS did not affect this positivity.

Long-Term Prognosis of Asthma-Bronchiectasis Overlapped Patients: A Nationwide Population-Based Cohort Study.

PURPOSE: Asthma and bronchiectasis are common chronic respiratory diseases, and their coexistence is frequently observed but not well investigated. Our aim was to study the effect of comorbid bronchiectasis on asthma. METHODS: A propensity score-matched cohort study was conducted using the National Health Insurance Service-Health Screening Cohort database. From 2005 to 2008, 8,034 participants with asthma were weighted based on propensity scores in a 1:3 ratio with 24,099 participants without asthma. From the asthma group, 141 participants with overlapped bronchiectasis were identified, and 7,892 participants had only asthma. Clinical outcomes of acute asthma exacerbation(s) and mortality rates were compared among the study groups. RESULTS: The prevalence of bronchiectasis (1.7%) was 3 times higher in asthmatics than in the general population of Korea. Patients who had asthma comorbid with bronchiectasis experienced acute exacerbation(s) more frequently than non-comorbid patients (11.3% vs. 5.8%, P = 0.007). Time to the first acute exacerbation was also shorter in the asthmatics with bronchiectasis group (1,970.9 days vs. 2,479.7 days, P = 0.005). Although bronchiectasis was identified as a risk factor for acute exacerbation (adjusted odds ratio, 1.73; 95% confidence interval [CI], 1.05-2.86), there was no significant relationship between bronchiectasis and all-cause or respiratory mortality (adjusted hazard ratio [aHR], 1.17; 95% CI, 0.67-2.04 and aHR, 0.81; 95% CI, 0.11-6.08). CONCLUSIONS: Comorbid bronchiectasis increases asthma-related acute exacerbation, but it does not-raise the risk of all-cause or respiratory mortality. Close monitoring and accurate diagnosis of bronchiectasis are required for patients with frequent exacerbations of asthma.

Trends and risk factors in severe hypoglycemia among individuals with type 2 diabetes in Korea.

AIMS: Because of the development of new classes of antidiabetic drugs, hypoglycemic events were expected to decrease. We investigated the trends and risk factors for severe hypoglycemia in subjects with type 2 diabetes in Korea. METHODS: We conducted repeated cross-sectional analyses using a Korean National Health Insurance Service-National Sample Cohort from 2006 to 2015. Severe hypoglycemia was defined as hospitalization or a visit to an emergency department with diagnosis of hypoglycemia using ICD-10 codes. RESULTS: During the study period, the prevalence of type 2 diabetes continuously increased. The percentage of patients prescribed metformin and dipeptidyl peptidase-4 inhibitor increased, while the use of sulfonylurea decreased considerably, especially since 2009. The proportion of patients prescribed ≥3 classes of drugs continually increased. Age-standardized incidence of severe hypoglycemia per 1000 patients with diabetes increased from 6.00 to 8.24 between 2006 and 2010, and then fell to 6.49 in 2015. Predictors of severe hypoglycemia included female, older age, comorbidities, polypharmacy, and sulfonylurea or insulin usage. CONCLUSIONS: Trends of severe hypoglycemia were associated with changes in drug classes rather than number of antidiabetic drugs. Relentless efforts to reduce the prescription of drugs with a high risk of hypoglycemia should be implemented, particularly for older women with multiple comorbidities.

Sex differences in the association between the APOEε4 allele and hearing impairment: A longitudinal memory clinic study.

BACKGROUND: The APOEε4 allele and hearing impairment are risk factors for dementia. Cross-sectional studies have shown controversial findings regarding the relationship between APOEε4 and hearing impairment. These may be explained by reported sex differences in the association between APOEε4 and some Alzheimer's disease biomarkers. We aimed to investigate APOEε4 and hearing impairment in a longitudinal setting considering the modifying effects of sex on APOEε4. METHODS: In total, 1810 subjects with APOE genotype at Ilsan Hospital memory clinics were linked to the longitudinal National Health Insurance Service database with International Statistical Classification of Diseases and Related Health Problems 10th revision (ICD-10) diagnosis codes of hearing impairment. After excluding cases with prevalent hearing impairment and incomplete records, 1092 subjects were analyzed for the period January 2004-July 2019. We used Cox proportional hazard models with or without adjustment for education, hypertension, diabetes, and cognitive function. Effect modification was analyzed by sex stratification and by adding APOEε4 by sex interaction terms. RESULTS: Hearing impairment did not differ between APOEε4 carriers and non-carriers. Sex-stratification analysis with an unadjusted model showed men with APOEε4 developed more hearing impairment than men without (HR 1.90, 95% CI 1.20-3.01), but women did not. The results remained similar in covariate-adjusted models. The interaction between APOEε4 and sex was also significant regardless of adjustment. CONCLUSIONS: Our longitudinal analyses suggested male memory clinic visitors with APOEε4 allele were more likely to develop hearing impairment than those without the genotype. This group may benefit more from regular monitoring and preventive measures for hearing impairment.

Smoking and the Risk of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Infection.

INTRODUCTION: It is unclear whether smokers are more vulnerable to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. This study aimed to evaluate the association between smoking and the risk of SARS-CoV-2 infection. METHODS: A matched case-control study was conducted using a large nationwide database. The case group included patients with SARS-CoV-2 infection confirmed by the Korea Centers for Disease Control and Prevention, and the control group was randomly sampled from the general Korean population in the National Health Insurance Service database by matching sex, age, and region of residence. Conditional logistic regression models were used to investigate whether the risk of infection with SARS-CoV-2 was affected by smoking status. RESULTS: A total of 4167 patients with SARS-CoV-2 infection and 20 937 matched controls were enrolled. The proportion of ex-smokers and current smokers was 26.6% of the total participants. In multivariate analysis, smoking was not associated with an increased risk of SARS-CoV-2 infection (odds ratio [OR] = 0.56, confidence interval [CI] = 0.50-0.62). When ex-smokers and current smokers were analyzed separately, similar results were obtained (current smoker OR = 0.33, CI = 0.28-0.38; ex-smoker OR = 0.81, CI = 0.72-0.91). CONCLUSIONS: This study showed that smoking may not be associated with an increased risk of SARS-CoV-2 infection. Smoking tends to lower the risk of SARS-CoV-2 infection; however, these findings should be interpreted with caution. IMPLICATIONS: It is unclear whether smokers are more vulnerable to coronavirus disease 2019. In this large nationwide study in South Korea, smoking tended to lower the risk of infection with severe acute respiratory syndrome coronavirus 2. However, these findings should be interpreted with caution, and further confirmatory studies are required.

Impact of COPD on COVID-19 prognosis: A nationwide population-based study in South Korea.

Underlying chronic respiratory disease may be associated with the severity of coronavirus disease 2019 (COVID-19). This study investigated the impact of chronic obstructive pulmonary disease (COPD) on the risk for respiratory failure and mortality in COVID-19 patients. A nationwide retrospective cohort study was conducted in 4610 patients (≥ 40 years old) infected with COVID-19 between January 20 and May 27, 2020, using data from the Ministry of Health and Welfare and Health Insurance Review and Assessment Service in Korea. The clinical course and various clinical features were compared between COPD and non-COPD patients, and the risks of respiratory failure and all-cause mortality in COPD patients were analyzed using a multivariate logistic regression model. Among 4610 COVID-19 patients, 4469 (96.9%) and 141 (3.1%) were categorized into the non-COPD and COPD groups, respectively. The COPD group had greater proportions of older (≥ 60 years old) (78.0% vs. 45.2%, P < 0.001) and male (52.5% vs. 36.6%, P < 0.001) patients than the non-COPD group. Relatively greater proportions of patients with COPD received intensive critical care (7.1% vs. 3.7%, P = 0.041) and mechanical ventilation (5.7% vs. 2.4%, P = 0.015). Multivariate analyses showed that COPD was not a risk factor for respiratory failure but was a significant independent risk factor for all-cause mortality (OR = 1.80, 95% CI 1.11-2.93) after adjustment for age, sex, and Charlson Comorbidity Index score. Among COVID-19 patients, relatively greater proportions of patients with COPD received mechanical ventilation and intensive critical care. COPD is an independent risk factor for all-cause mortality in COVID-19 patients in Korea.

Impact of comorbid asthma on severity of coronavirus disease (COVID-19).

The severity of the coronavirus disease (COVID-19) is associated with various comorbidities. However, no studies have yet demonstrated the potential risk of respiratory failure and mortality in COVID-19 patients with pre-existing asthma. We selected 7272 adult COVID-19 patients from the Korean Health Insurance Review and Assessment COVID-19 database for this nationwide retrospective cohort study. Among these, 686 patients with asthma were assessed by their severities and evaluated by the clinical outcome of COVID-19 compared to patients without asthma. Of 7272 adult COVID-19 patients, 686 with asthma and 6586 without asthma were compared. Asthma was not a significant risk factor for respiratory failure or mortality among all COVID-19 patients (odds ratio [OR] = 0.99, P = 0.997 and OR = 1.06, P = 0.759) after adjusting for age, sex, and the Charlson comorbidity score. However, a history of acute exacerbation (OR = 2.63, P = 0.043) was significant risk factors for death among COVID-19 patients with asthma. Asthma is not a risk factor for poor prognosis of COVID-19. However, asthma patients who had any experience of acute exacerbation in the previous year before COVID-19 showed higher COVID-19-related mortality, especially in case of old age and male sex.

A Community-Based Intervention for Improving Medication Adherence for Elderly Patients with Hypertension in Korea.

The chronic disease management program, a community-based intervention including patient education, recall and remind service, and reduction of out-of-pocket payment, was implemented in 2005 in Korea to improve patients' adherence for antihypertensive medications. This study aimed to assess the effect of a community-based hypertension intervention intended to enhance patient adherence to prescribed medications. This study applied a non-equivalent control group design using the Korean National Health Insurance Big Data. Hongcheon County has been continuously implementing the intervention program since 2012. This study involved a cohort of patients with hypertension aged >65 and <85 years, among residents who lived in the study area for five years (between 2010 and 2014). The final number of subjects was 2685 in both the intervention and control region. The indirect indicators were analyzed as patients' adherence and level of continuous treatment using the difference-in-difference regression. The proportion of hypertensive patients who continuously received insurance benefits for >240 days in 2014 was 81.0% in the intervention region and 79.7% in the control region. The number of dispensations per prescription and the dispensation days per hypertensive patient in the intervention region increased by approximately 10.88% and 2.2 days on average by month, respectively, compared to those in the control region. The intervention program encouraged elderly patients with hypertension to receive continuous care. Another research is needed to determine whether further improvement in the continuity of comprehensive care will prevent the progression of cardiovascular diseases.