Treatment patterns and cost of exacerbations in patients with chronic obstructive pulmonary disease using multiple inhaler triple therapy in South Korea.

BACKGROUND: Multiple inhaler triple therapy (MITT), comprising inhaled corticosteroids (ICS), long-acting beta-agonists (LABA), and long-acting muscarinic antagonists (LAMA), has been used as an escalation treatment for patients with chronic obstructive pulmonary disease (COPD). However, real-world use of MITT has not been investigated in Asia, including South Korea. This study reports baseline characteristics of patients with COPD initiated on MITT in South Korea, and their treatment patterns. Healthcare resource utilization (HRU) and costs associated with COPD exacerbations following MITT initiation were also assessed. METHODS: This was a retrospective cohort study using the South Korea National Health Insurance database (2014-2018). Included patients were ≥ 40 years, had a COPD diagnosis, were newly initiated on MITT and had ≥ 12 months' data both before (baseline) and after index date (the first day with overlapping supply of all MITT components). Treatment immediately before initiation and immediately following discontinuation of MITT were identified, and proportion of days covered (PDC) by MITT was calculated. HRU and costs (per person per year [PPPY]) associated with exacerbations were identified following MITT initiation; costs were calculated using the average 2020 exchange rate (0.0008 USD/KRW). RESULTS: Among 37,400 patients, the mean age was 69 (SD 10) years and 73% were males; 56% had ≥ 1 COPD exacerbation during the baseline period, with a mean of 2 (SD 5) events/year. ICS/LABA was the most frequent regimen prescribed immediately before initiation (37%) and immediately following discontinuation (41% of 34,264 patients) of MITT. At 3, 6, and 12 months from treatment initiation, mean PDC was 81%, 63% and 49%, respectively; median treatment duration was 102 days. The mean (95% confidence interval [CI]) number of total visits for severe COPD exacerbations was 0.77 PPPY (0.75-0.78); mean PPPY total healthcare costs were 2093 USD. CONCLUSIONS: Patients with COPD in South Korea experienced frequent exacerbations prior to MITT, and PDC by MITT was low. Patients may benefit from early optimization of COPD therapy, and greater emphasis on adherence to inhaled COPD therapy. Severe exacerbations were found to incur substantial costs; treatment alternatives that can reduce the rate of severe exacerbations are likely to minimize healthcare costs.

Assessment of genetic factor and depression interactions for asthma symptom severity in cohorts of childhood and elderly asthmatics.

It is well known that depression is associated with asthma symptoms. We assessed the combined effects of genetic factors and depression on asthma symptom severity using Bayesian network (BN) analysis. The common 100 top-ranked single-nucleotide polymorphisms (SNPs) were obtained from two genome-wide association studies of symptom severity in two childhood asthmatics trials (CAMP (Childhood Asthma Management Program) and CARE (Childhood Asthma Research and Education)). Using SNPs plus five discretized variables (depression, anxiety, age, sex, and race), we performed BN analysis in 529 CAMP subjects. We identified two nodes (depression and rs4672619 mapping to ERBB4 (Erb-B2 receptor tyrosine kinase 4)) that were within the Markov neighborhood of the symptom node in the network and then evaluated the interactive effects of depressive status and rs4672619 genotypes on asthma symptom severity. In childhood asthmatics with homozygous reference alleles, severe depression was related to less severe symptoms. However, in childhood asthmatics with heterozygous alleles and homozygous variant alleles, depression and symptom severity showed a positive correlation (interaction permutation P value = 0.019). We then tried to evaluate whether the interactive effects that we found were sustained in another independent cohort of elderly asthmatics. Contrary to the findings from childhood asthmatics, elderly asthmatics with homozygous reference alleles showed a positive correlation between depression and symptom severity, and elderly asthmatics with heterozygous alleles and homozygous variant alleles showed a negative correlation (interaction permutation P value = 0.003). In conclusion, we have identified a novel SNP, rs4672619, that shows interactive effects with depression on asthma symptom severity in childhood and elderly asthmatics in opposite directions.

Incidence of Stevens-Johnson Syndrome and Toxic Epidermal Necrolysis: A Nationwide Population-Based Study Using National Health Insurance Database in Korea.

BACKGROUND: Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are life-threatening diseases; however, it is hard to estimate their incidence due to the rarity of these diseases. We evaluated the incidence of SJS and TEN using a nationwide administrative database. METHODS: We used a national medical insurance review system (Health Insurance Review and Assessment) database which contained the claim data of the entire nation from 2009 to 2013 to estimate the accurate incidence of SJS and TEN in Korea. The diagnostic codes of L511 (SJS) or L512 (TEN) from the International Classification of Diseases-10th revision were used to define the target study population. We also retrospectively followed up a 2011 SJS and TEN cohort for 24 months in order to assess the in-hospital mortality, related complications and total claims cost due to SJS and TEN. RESULTS: A total of 1,167 (938 SJS and 229 TEN) cases were newly diagnosed from 2010 to 2013. The age- and sex-standardized annual incidences estimated in this study were 3.96 to 5.03 in SJS and 0.94 to 1.45 in TEN per million. There was no significant change in annual incidence throughout the study periods. When analyzed by 10-year age groups, the annual incidence was the lowest in group 20-29 years and the highest in group 70 for both SJS and TEN. Based on the 2011 cohort analysis, the in-hospital mortality were 5.7 and 15.1% for SJS and TEN, respectively. The mortality increased with age, particularly, after 40 years of age. Among the complications related with SJS or TEN, ocular sequelae was the most common (43.1 and 43.4% of SJS and TEN patients, respectively) followed by urethral sequelae (5.7 and 9.4% of SJS and TEN patients, respectively). CONCLUSION: Overall, our data suggest that SJS, and TEN are infrequent but constantly arise throughout the years.

Allergies are still on the rise? A 6-year nationwide population-based study in Korea.

BACKGROUND: Some western countries recently have shown a slowdown in the incidence of allergic diseases after worldwide increasing trends, but there are few data from Asian populations concerning changing trend of allergic diseases. We evaluated the recent trends in the prevalence of asthma and other allergic diseases in Korea. METHODS: From the database of Korean National Health Insurance, a nationwide diagnostic data from 2009 to 2014 were extracted and the national prevalence was analyzed. RESULTS: The prevalence per 1000 people of atopic dermatitis, allergic rhinitis, and asthma in 2014 was 19.0, 133.1, and 36.3, respectively. The prevalence of three diseases was highest in the age group under 10 as, 95.0, 384.1, and 132.1 per 1000 people, while the prevalence in the over-10-year-group was only 11.6, 109.5, and 27.3, respectively. The prevalence of atopic dermatitis and allergic rhinitis gradually decreased with older age, but the prevalence of asthma showed a re-increasing pattern from the age group 30-39 and reached another peak for the age group 70-79. During the study period, the prevalence of asthma and atopic dermatitis showed decreasing tendency. In contrast, the prevalence of allergic rhinitis steadily increased until 2013, especially in the age group under 10. CONCLUSIONS: The national prevalence of atopic dermatitis, and asthma did not show noticeable increase any more in Korea. However, the prevalence of allergic rhinitis still on the rise until recently, especially in the age group under 10. This is the first report in Asia suggesting a slowdown of the incidence of allergic diseases.

New insight into the assessment of asthma using xenon ventilation computed tomography.

BACKGROUND: Image analyses include computed tomography (CT), magnetic resonance imaging, and xenon ventilation CT, which is new modality to evaluate pulmonary functional imaging. OBJECTIVE: To examine the usefulness of dual-energy xenon ventilation CT in asthmatic patients. METHODS: A total of 43 patients 18 years or older who were nonsmokers were included in the study. Xenon CT images in wash-in and wash-out phases were obtained at baseline and after inhalation of methacholine and salbutamol. The degrees of ventilation defects and xenon trappings were evaluated through visual analysis. RESULTS: Ventilation defects and xenon trapping were significantly increased and decreased after methacholine challenge and salbutamol inhalation, respectively (P < .005). The ventilation abnormalities were not significantly related to the percentage of forced expiratory volume in 1 second (FEV1) or the ratio of FEV1 to forced vital capacity. Xenon trappings after salbutamol inhalation were negatively related to the scores of the asthma control test, wheezing, or night symptoms, with statistical significance (P < .05), whereas, FEV1 showed no significant correlation with symptom scores. Baseline FEV1 was significantly lower and dyspnea and wheezing were more severe in the non-full reversal group than in the full reversal group after salbutamol inhalation in xenon CT (P < .05). The degree of ventilation defects were positively correlated with FEV1 improvement after 3 months of treatment (P = .02). CONCLUSION: The results of this study suggest that xenon ventilation CT can be used as a new method to assess ventilation abnormalities in asthma, and these ventilation abnormalities can be used as novel parameters that reflect the status of asthma control and symptom severity.

Economic costs for adult asthmatics according to severity and control status in Korean tertiary hospitals.

OBJECTIVE: The prevalence of asthma is increasing, and asthma causes considerable socioeconomic burden worldwide. Few studies have been conducted to evaluate the risk factors associated with economic cost of asthma in Korea. This study evaluated asthma cost according to severity, control, and patient factors in Korean tertiary hospitals. METHODS: Direct and indirect costs were assessed in physician-diagnosed adult asthmatics recruited from eight tertiary hospitals in Korea. Official direct medical costs were derived from the analysis of 1-year expenditures related to hospital care utilization and asthma medication. Nonofficial medical costs, nonmedical direct costs, and indirect costs were investigated using a questionnaire designed specifically for the study. RESULTS: A total of 314 patients with persistent asthma were recruited. Both direct and indirect costs were significantly higher for patients with severe persistent asthma than for those with mild and moderate persistent asthma ($2214 vs. $871 and $978, p < .001; $2927 vs. $490 and $443, p < .001, respectively). Costs of asthma increased significantly in poorly controlled compared with somewhat controlled and well-controlled asthma ($7009.8 vs. $2725.3 vs. $1517.3, respectively; p < .001). After stratification for severity, a significant cost increase in the poorly controlled asthma group was observed only for indirect costs and not for direct costs. A multivariate analysis showed that female gender was a risk factor for increased indirect costs. CONCLUSION: The burden of asthma was higher both for patients with severe persistent asthma and for patients with poorly controlled asthma. More effective strategies are needed to improve control status, particularly targeting patients with severe asthma.

The financial burden of asthma: a nationwide comprehensive survey conducted in the republic of Korea.

PURPOSE: Asthma-related morbidity and mortality are increasing, and the financial burden imposed by this condition will substantially increase. Nevertheless, little information is available regarding the nature and magnitude of the burden due to asthma at the national level. This study was conducted to characterize the financial burden imposed by asthma in the Republic of Korea at the national level. METHODS: The overall prevalence of asthma and the costs of related medical services were determined using data from the National Health Insurance Corporation, which is responsible for the National Health Insurance scheme. Indirect costs, including expenditures on complementary and alternative medicines, and the economic impact of an impaired quality of life (intangible costs) were estimated by surveying 660 asthmatics, and these estimates were transformed to the national level using the prevalence of asthma. RESULTS: The prevalence of asthma and total costs related to the disease in 2004 were 4.19% and $2.04 billion, respectively. Direct costs and indirect costs contributed equally to total costs (46.9% and 53.1%, respectively). However, when intangible costs were included, total costs rose to $4.11 billion, which was equivalent to 0.44% of the national gross domestic product in 2004. CONCLUSIONS: The results provide evidence that asthma is a major health cost factor in the Republic of Korea and that intangible costs associated with asthma are significant cost drivers.

The current status of asthma in Korea.

A systematic review of English and Korean articles published between 1990 and 2004 and a search of database and various online resources was conducted to determine the prevalences, mortality rates, socioeconomic burden, quality of life, and treatment pattern of asthma in Korean adults and children. Asthma morbidity and mortality in Korea are steadily increasing. The prevalence of asthma in Korea is estimated to be 3.9% and its severity is often underestimated by both physicians and patients. Mortality resulting from chronic lower respiratory diseases including asthma increased from 12.9 to 22.6 deaths per 100,000 of the population between 1992 and 2002. Disease severity, level of control, and symptom state were all found to negatively impact the quality of life of asthmatics. Although international and Korean asthma management guidelines are available, familiarity with and implementation of these guidelines by primary care physicians remain poor.