Health Insurance Review Agency Research Articles

One-Year Clinical Outcomes After Diagnosis According to Early Medication Adherence in First-Episode Schizophrenia: A Nationwide, Health Insurance Data-Based Retrospective Cohort Study

Objectives: Early pharmacologic intervention is considered necessary for improving the prognosis in patients with first-episode schizophrenia (FES). However, few nationwide population-based studies have focused on early medication adherence. We investigated the status of early adherence to antipsychotics and the effect of early adherence on later clinical outcomes in FES.Methods: We used data from the South Korean Health Insurance Review Agency database (2009-2021). We selected 28,931 patients with FES who had a prescription record of at least one antipsychotic medication within 180 days after their diagnosis. We measured early medication adherence using the medication possession ratio (MPR) and compared demographic characteristics and results of psychiatric hospitalization between the adherence group (0.6≤MPR<1.1) and the non-adherence group (MPR<0.6).Results: The average early medication adherence was 0.82 by MPR, and the non-adherence group accounted for 15.6% of all subjects. From 1 to 2 years after diagnosis, the adherence group showed a higher number of psychiatric hospitalizations per hospitalized patient but a shorter duration than the non-adherence group. Additionally, the proportion of patients who experienced psychiatric hospitalizations was smaller in the adherence group.Conclusion: In patients with FES, early medication adherence is associated with lower rates of psychiatric hospitalization and shorter hospitalization durations.

Risk of Breast Cancer in Association with the Use of Second-generation Antipsychotics.

Previous studies regarding the relationship between the risk of breast cancer (BC) and antipsychotics use have reported inconsistent findings. Insufficient sample size and/or observation period may have hindered revealing the risk of BC associated with antipsychotics use. We aimed to investigate whether the use of second-generation antipsychotics (SGA) is associated with increased risk of BC. We used the Health Insurance Review Agency database in South Korea between 2008 and 2018. The index date was determined as the date of the first antipsychotic prescription. We selected women prescribed SGAs for more than 30 days within a year from the index date and age-matched controls, yielding 498,970 cases and 997,940 controls. The Cox proportional hazards regression model was used for estimating the risk. The incidence rates of BC were 109.74 and 101.51 per 100,000 person-years in the case and control groups, respectively. There was an increased risk of BC in the case group (hazard ratio [HR] = 1.08, 95% confidence interval [CI] 1.04-1.13). There was a higher risk of BC in subjects prescribed with ≥ 10,000 mg of olanzapine equivalent dose (HR = 1.29, 95% CI 1.14-1.46) than those with < 10,000 mg (HR = 1.05, 95% CI 1.00-1.11). The increased risk of BC in the case group became significant after six years of the observation period (≥ 6 years: HR = 1.24, 95% CI 1.14-1.35, 3 to < 6 years: HR = 1.06, 95% CI 0.97-1.15, < 3 years: HR = 1.02, 95% CI 0.95-1.09). This study indicated that the use of SGAs is associated with increased risk of BC in a long-term relationship with a dose-response pattern.

Impact of the early phase of the COVID-19 pandemic on the use of mental health services in South Korea: a nationwide, health insurance data-based study.

The coronavirus disease 2019 (COVID-19) pandemic has profoundly affected the utilization of mental health services. Existing evidence investigating this issue at the nationwide level is lacking, and it is uncertain whether the effects of the COVID-19 pandemic on the use of psychiatric services differs based on psychiatric diagnosis. Data from the claims database between October 2015 and August 2020 was obtained from the Health Insurance Review and Assessment agency in South Korea. Based on the main diagnostic codes, psychiatric patients were identified and categorized into diagnostic groups (anxiety disorders, bipolar and related disorders, depressive disorders, and schizophrenia spectrum disorders). We calculated the number of psychiatric inpatients and outpatients and the medication adherence of patients for each month. We compared the actual and predicted values of outcomes during the COVID-19 pandemic and performed interrupted time-series analyses to test the statistical significance of the impact of the pandemic. During the COVID-19 pandemic, the number of inpatients and admissions to psychiatric hospitals decreased for bipolar and related disorders and depressive disorders. In addition, the number of patients admitted to psychiatric hospitals for schizophrenia spectrum disorders decreased. The number of psychiatric outpatients showed no significant change in all diagnostic groups. Increased medication adherence was observed for depressive, schizophrenia spectrum, and bipolar and related disorders. In the early phase of the COVID-19 pandemic, there was a trend of a decreasing number of psychiatric inpatients and increasing medication adherence; however, the number of psychiatric outpatients remained unaltered.

Delay in psychiatric hospitalization from the diagnosis of first-episode schizophrenia and its association with clinical outcomes and direct medical costs: a nationwide, health insurance data-based study

BackgroundEarly intervention is essential for improving the prognosis in patients with first-episode schizophrenia (FES). The Mental Health Act limits involuntary hospitalization in South Korea to cases where an individual exhibits both a mental disorder and a potential for harming themselves or others, which could result in a delay in the required treatment in FES. We investigated the effect of delay in the first psychiatric hospitalization on clinical outcomes in FES.MethodsThe South Korean Health Insurance Review Agency database (2012–2019) was used. We identified 15,994 patients with FES who had a record of at least one psychiatric hospitalization within 1 year from their diagnosis. A multivariate linear regression model and a generalized linear model with a gamma distribution and log link were used to examine associations between the duration from the diagnosis to the first psychiatric admission and clinical outcomes as well as direct medical costs after 2 and 5 years.ResultsWithin both the 2-year and the 5-year period, longer durations from the diagnosis to the first psychiatric admission were associated with an increase in the number of psychiatric hospitalizations (2-y: B = 0.003, p = 0.003, 5-y: B = 0.007, p = 0.001) and an increase in direct medical costs (total: 2-y: B = 0.005, p < 0.001, 5-y: B = 0.004, p = 0.005; inpatient care: 2-y: B = 0.005, p < 0.001, 5-y: B = 0.004, p = 0.017).ConclusionsEarlier psychiatric admission from the diagnosis is associated with a decrease in the number of psychiatric admissions as well as in direct medical costs in patients with FES.

Multiple metabolic comorbidities and their consequences among patients with peripheral arterial disease.

Older adults with peripheral arterial disease (PAD) have increased risks of major cardiovascular events and hospitalization. Metabolic comorbidities, such as hypertension, diabetes mellitus, and dyslipidemia, are common risk factors for these unfavorable health events. This study aimed to determine how multiple metabolic comorbidities affect the risk of adverse health outcomes in older adults with PAD. A retrospective cohort study was adopted using administrative claim data from the Health Insurance Review and Assessment Service Agency. The study sample included 3,122 older adults (≥ 65 years old) with at least one PAD diagnosis in an inpatient setting from 2011 to 2013 and who had at least one follow-up visit after hospitalization by 2018. The three metabolic comorbidities were defined as having at least two diagnostic claims or one prescription per year of anti-hypertensive, anti-diabetic, or anti-dyslipidemic medications for the corresponding diagnosis. The outcome variables included major adverse cardiovascular events (MACEs) and major adverse limb events (MALE). Kaplan-Meier survival curves demonstrated that PAD patients with more metabolic comorbidities had shorter MACE-free and MALE-free periods. Adjusted Cox proportional hazards analyses suggested significant additive effects of multiple metabolic comorbidities on increased risks of MACE and MALE among older adults with PAD. Lower socioeconomic status and non-metabolic comorbidities also increased the risk of MACE. Male sex, being young-old (65–74 years), and a higher proportion of inpatient claims increased the risk of MALE. The findings of this study suggest the need for a comprehensive care program for older adults with PAD and metabolic comorbidities. In addition, the healthcare utilization pattern should be considered when designing preventive care for older patients with comorbidities to manage PAD at an earlier stage.

Comparative effectiveness of antipsychotic monotherapy and polypharmacy in schizophrenia patients with clozapine treatment: A nationwide, health insurance data-based study

Clozapine is the most effective antipsychotic for treatment-resistant schizophrenia (TRS). However, it remains uncertain whether antipsychotic augmentation to clozapine has the superior effectiveness over clozapine alone and the effect size of clozapine compared to other antipsychotic drugs in TRS. Therefore, we examined the comparative effectiveness of antipsychotic monotherapy and polypharmacy on the risk of psychiatric admission and treatment discontinuation in TRS. Data were collected from the Health Insurance Review Agency database between January 2010 and December 2019 in South Korea. Among prevalent patients with schizophrenia, we defined 22,327 patients with TRS as those who had been prescribed with clozapine at least once during the entire observation period. Stratified Cox proportional hazards regressions were performed using data on all antipsychotic prescriptions of patients with TRS to investigate the risk of psychiatric hospitalization and treatment discontinuation associated with antipsychotic treatment. In individual comparisons, clozapine monotherapy was the most effective for the risk of psychiatric hospitalization compared to no use (hazard ratio [HR] = 0.23, 95% confidence interval [CI] = 0.22–0.25). In group comparisons, clozapine with long-acting injectable (LAI) second-generation antipsychotics (SGA) was superior to clozapine monotherapy for the risk of psychiatric hospitalization (HR = 0.60, 95%CI = 0.41–0.88). Clozapine monotherapy was associated with the lowest risk of treatment discontinuation in the individual and group comparisons. This retrospective observational population-based study reports that clozapine with LAI SGA is more effective in lowering the risk of psychiatric hospitalization in antipsychotic group comparison with the reference of clozapine monotherapy.

Risk of treatment discontinuation and psychiatric hospitalization associated with early dose reduction of antipsychotic treatment in first-episode schizophrenia: A nationwide, health insurance data-based study.

We investigated the impact of early dose reduction of antipsychotic treatment on the risk of treatment discontinuation and psychiatric hospitalization in patients with first-episode schizophrenia (FES). The Health Insurance Review Agency database in South Korea was used to include 16 153 patients with FES. At 6 months from their diagnosis, the patients were categorized by the magnitude of dose reduction (no reduction, 0%-50%, and >50%). With a reference of no reduction, the risk of treatment discontinuation and psychiatric hospitalization associated with dose reduction in the 1-year follow-up period after the first 6 months was examined with a Cox proportional hazard ratio model stratified by the mean daily olanzapine-equivalent dose in the first 3 months (<10, 10 to 20, >20 mg/day). A >50% dose reduction was associated with an increased risk of treatment discontinuation in all subgroups (<10 mg/day: hazard ratio [HR] =1.44, 95% confidence interval [CI] =1.24-1.67 [P <0.01]; 10-20 mg/day: HR =1.60, 95% CI =1.37-1.86 [P <0.01]; and >20 mg/day: HR =1.62, 95% CI =1.37-1.91 [P <0.01]). In the subgroup taking <10 mg/day, an association of 0%-50% dose reduction with an increased risk of treatment discontinuation was observed (HR =1.20, 95% CI =1.09-1.31; P <0.01). A > 50% dose reduction was associated with increased risk of psychiatric hospitalization only in the subgroup taking <10 mg/day (HR =1.48, 95% CI =1.21-1.80; P <0.01). Our results suggest that an above certain dose of antipsychotic drugs is required to prevent psychiatric hospitalization, and extensive dose reduction of antipsychotic drugs could result in a higher risk of treatment discontinuation.

Diagnostic conversion from unipolar to bipolar affective disorder–A population-based study

Objectives: It is essential to clinically distinguish bipolar affective disorder from unipolar affective disorders. However, patients previously diagnosed with unipolar affective disorder are sometimes later diagnosed with bipolar affective disorder, known as diagnostic conversion. Here we investigated diagnostic conversion using data from a nationwide population-based register. Methods: We obtained claims data from 2007 to 2020 in Korea's Health Insurance Review Agency database and identified a cohort of patients who were diagnosed with unipolar depression in 2009 without prior psychiatric diseases within the previous 2 years. We studied the rate of diagnostic conversion and risk factors, especially antidepressants. Results: About 6.5% of patients underwent diagnostic conversion during the observation period. Younger age at disease onset and usage of antidepressants increased the relative risk for diagnostic conversion. Patients using serotonin-norepinephrine reuptake inhibitors (SNRI) showed more than twice the risk compared to no usage of antidepressant. Limitation: First, this study was based on the population-based register data. Thus, we defined the patient cohort diagnosed with unipolar depression with strict inclusion criteria. Second, the exposure time differed between different antidepressants. Third, we estimated the relative risk for diagnostic conversion compared to no use of antidepressants. Moreover, we could not rule out the potential influence of antidepressant polypharmacy. Conclusion: We confirmed diagnostic conversion in some patients and identified younger age or usage of antidepressants, especially SNRI, as risk factors. Because unipolar and bipolar affective disorders show different disease courses or prognoses and have different treatment strategies, clinicians should be mindful of diagnostic conversion.

Use of olanzapine compared with clozapine for treatment-resistant schizophrenia in a real-world setting: nationwide register-based study.

Clozapine is generally considered as the treatment of choice for patients with treatment-resistant schizophrenia (TRS). However, its superiority has recently been questioned because olanzapine has been suggested as non-inferior to clozapine in its effectiveness. We aimed to investigate the current status of clozapine prescriptions to identify any disparity between clinical guidelines and real-world practices. In this study, we utilised the Health Insurance Review Agency database in the Republic of Korea to investigate the real-world effectiveness of clozapine for patients with TRS. We compared differences in patient variables before and after clozapine administration, and we also performed survival analyses for both psychiatric admissions and emergency room visits among patients who used clozapine or olanzapine. This study investigated an incident cohort of 64 442 patients, and 2338 patients have been prescribed clozapine. Of these, 998 patients had TRS. In survival analysis, clozapine showed a worse survival rate for psychiatric admissions than olanzapine (hazard ratio 0.615). We also identified that clinicians tended to try a number of antipsychotics, as recommended, before starting patients on clozapine. In conclusion, we found that olanzapine led to higher survival rates for psychiatric admissions than clozapine. Thus, considering the risk of serious adverse effects, clozapine may be used conservatively. Considering several studies advocating superior efficacy of clozapine, further studies with extensive data are recommended.

Clinical Study Using Healthcare Claims Database.

The healthcare claims database is a database created using claims data accumulated while operating the government's health insurance system. The National Health Insurance Service (NHIS) provides benefits for health promotion, prevention, diagnosis, and disease and injury treatment, as well as for rehabilitation, birth, and death. Ninety-seven percent of the total population is enrolled in the NHIS; individuals pay a monthly insurance contribution to the system, and the NHIS pays a portion of the cost of reimbursement items to the medical institution when the subscriber receives medical services. In this process, the NHIS and Health Insurance Review Agency (HIRA) decide on payment, and claims data are documented items that medical institutions claim to these government agencies. The NHIS and HIRA have established a database to support policy and academic research, and they provide this database to researchers. Health claims data are representative of the nation, reflecting the actual medical environment. They also shorten the time and cost required for research and have several advantages as research data. However, studies should be conducted with an understanding of the limitations of claims data, a sufficient understanding of the characteristics of the Korean insurance system, and criteria for providing reimbursed services. Moreover, validating the healthcare claims database will facilitate more useful and reliable research.

Effects of comorbid alcohol use disorder on the clinical outcomes of first-episode schizophrenia: a nationwide population-based study

BackgroundAlcohol use disorder (AUD) is a common psychiatric comorbidity in schizophrenia, associated with poor clinical outcomes and medication noncompliance. Most previous studies on the effect of alcohol use in patients with schizophrenia had limitations of small sample size or a cross-sectional design. Therefore, we used a nationwide population database to investigate the impact of AUD on clinical outcomes of schizophrenia.MethodsData from the Health Insurance Review Agency database in South Korea from January 1, 2007 to December 31, 2016 were used. Among 64,442 patients with first-episode schizophrenia, 1598 patients with comorbid AUD were selected based on the diagnostic code F10. We performed between- and within-group analyses to compare the rates of psychiatric admissions and emergency room (ER) visits, and medication possession ratio (MPR) between the patients with comorbid AUD and control patients matched for the onset age, sex, and observation period.ResultsThe rates of psychiatric admissions and ER visits in both groups decreased after the time point of diagnosis of AUD; however, the decrease was significantly greater in the patients with comorbid AUD compared to the control patients. While the comorbid AUD group showed an increase in MPR after the diagnosis of AUD, MPR decreased in the control group. The rates of psychiatric admissions, ER visits, and MPR were worse in the comorbid AUD group both before and after the diagnosis of AUD.ConclusionsThe results emphasize an importance of psychiatric comorbidities, especially AUD, in first-episode schizophrenia and the necessity of further research for confirmative findings of the association of AUD with clinical outcomes of schizophrenia.

Antipsychotic treatment and risk of discontinuation and hospitalization in first-episode schizophrenia: a nationwide population-based study.

Current evidence on antipsychotic treatment and risk of psychiatric hospitalization in first-episode schizophrenia (FES) is largely based on the findings from randomized clinical trials (RCTs). However, the generalization of the findings to real-world patients is limited due to inherent caveats of the RCT. We aimed to investigate the treatment discontinuation and risk of psychiatric hospitalization using a nationwide population database. The Health Insurance Review Agency database in South Korea was obtained, and the observation period started from 1 January 2009 to 31 December 2016. We defined the maintenance period as the period from 6-month after the diagnosis of schizophrenia, which is utilized for the main results. For a total of 44 396 patients with FES, a within-individual Cox regression model was used to compare the risk of the treatment discontinuation and psychiatric hospitalization. In group comparison, a long-acting injectable (LAI) antipsychotic group was associated with the lowest risk of the treatment discontinuation (0.64, 0.55-0.75) and psychiatric hospitalization (0.29, 0.22-0.38) in comparison with a typical antipsychotic group and no use, respectively. Among individual antipsychotics, the lowest risk of the treatment discontinuation was observed in LAI paliperidone (0.46, 0.37-0.66) compared to olanzapine. Clozapine was found to be the most effective antipsychotic in lowering the risk of psychiatric hospitalization as monotherapy compared to no use (0.23, 0.18-0.31). In real-world patients with FES, LAI paliperidone and clozapine were associated with low treatment discontinuation and better effectiveness in lowering the risk of psychiatric hospitalization.

International Price Comparisons of Anticancer Drugs: A Scheme for Improving Patient Accessibility

Background: The demand for implementing a new listing scheme to expedite patient access to novel oncology drugs has increased in South Korea. This study was conducted to compare the prices of anticancer drugs between eight countries and to explore the feasibility of a ‘pre-listing and post-evaluation’ scheme to expedite patient access to oncology drugs. Methods: This study included 34 anticancer drugs, which were reimbursed between 1 January 2007 and 31 December 2017. The unit price and sales volume of the study drugs were collected from eight countries and IQVIA data, respectively. The prices were adjusted to estimate the ex-factory prices using the discount/rebate rate suggested by the Health Insurance Review Agency (HIRA). The four price indices of Laspeyres, Paasche, Fisher, and the unweighted index were calculated using the price in each country, the average price, and lowest price among the study countries. Each currency was converted using the currency exchange rate and purchasing power parity (PPP). The budget impact of implementing the proposed pre-listing and post-evaluation scheme on payers was calculated. Results: Based on the currency exchange rate, anticancer drug prices were higher in other countries (index range: 1.05–2.78) compared to Korea. The prices in Korea were similar to countries with the lowest prices. When the PPP was applied, prices were higher in the US, Germany, Italy, and Japan than in Korea (range: 1.10–2.13); however, the prices were lower in the UK, France, and Switzerland than in Korea (range: 0.72–0.99). The financial burden of implementing the pre-listing and post-evaluation scheme was calculated at 0.83% of the total anticancer drug sales value in Korea from 2013–2017. Conclusions: The prices of anticancer drugs in Korea were similar to the lowest prices among the seven other study countries. A pre-listing and post-evaluation scheme should be considered to improve patient access to novel anticancer drugs by reducing the reimbursement review time and uncertainties.

PCN87 Key Clinical and Economic Rationales for Oncology Reviews in South Korea

To study the clinical and economic rationales for oncology reviews assessed by the Health Insurance Review Agency (HIRA) in South Korea. Health technology assessment (HTA) reports for oncological indications published by HIRA in the last 5 years (2015 - 2019) were analyzed to identify the clinical and economic factors affecting decisions. A total of 48 decisions were identified. In the evaluation of benefit assessment, 81.25% demonstrated a valid adequacy of benefit, whereas 18.75% demonstrated non-benefit. Clinical factors driving positive decisions were better outcome results (67.3%), unmet need/life-threatening disease condition (11.54%), acceptable efficacy/effectiveness (3.85%), and similar efficacy (3.85%), whereas those leading to negative decisions were identified as uncertain efficacy/effectiveness (11.54%) and insufficient efficacy (1.92%). Similarly, economic factors leading to positive decisions were applicability of risk-sharing agreement (37.5%), cost-effectiveness (4.17%), and similar cost (2.08%). Negative decisions were mainly due to uncertain cost-effectiveness (27.08%), drug was not cost-effective (22.92%), and economic evaluation was not submitted (2.08%). Some drugs were exempted from economic evaluation (4.17%). Patients were asked to pay the total cost out of pocket in 6 cases due to high cost or uncertain cost-effectiveness. In 8 out of 10 cases where drugs were registered in > 3 foreign countries, the medicinal products under review were classified as drugs which can omit the submission of economic evaluation documents. The research indicates that oncology product manufacturers should provide robust clinical data to show better clinical outcome results and robust economic data to demonstrate drug cost-effectiveness to gain market access in South Korea. Risk-sharing agreements and economic evaluation exemptions improve patient accessibility for drugs without alternatives in life-threatening disease conditions. Uncertainties in clinical efficacy/effectiveness and cost-effectiveness are the key factors correlated with non-benefit. South Korea is planning to introduce a post-list review focusing on anticancer and orphan drugs.

PMH5 Assessing the IMPACT of New Policy for Patients with Mental Disorders on Cost of Drug Prescription: An Interrupted Time Series Analysis

In South Korea, the government had set a fixed daily upper limit of medical expenses for outpatient visits of patients with mental disorders (MD) in the Medical Aid (MA) program. Due to this policy, there was inequality in the use of prescribed drugs. Thus, in March 2017, the government implemented the new policy named the Comprehensive Plan on Mental Health Act, which is no fixed daily upper limit. I aimed to determine the impact of the new policy on the cost of drug prescription among pediatric patients with MD in the MA program compared to those in the non-MA program. Between 2015 and 2017, pediatric patients with MD were defined as those aged < 20 years for outpatient visits at least twice in a year with an MD (F code of ICD-10th) as a primary diagnosis from Korea Health Insurance Review and Assessment agency – Pediatric Patients Sample data. Prescription data were aggregated quarterly and the average drug costs were calculated. An interrupted time series analysis examined the impact of the new policy on a trend in the outcome of the daily average drug cost. Autoregression was tested by Durbin-Watson statistics (DWS). A total of 15,517 prescription bills (2,430 patients) for the MA and 403,895 bills (55,833 patients) for the non-MA program was included. After the implementation, the drug cost was increased at 1.9 times (after $45 vs. before $24) in the MA program. Contrarily, in the non-MA program, there was no statistically significant change (after $37 vs. before $39). The results of segmented regression analysis confirmed that the new policy had an impact on the increase of the average drug cost (beta=36.7, p<0.01) with no autoregression (DWS=2.2). This result implies the new policy for MA patients had an immediate impact. To assess the long-term impact, further studies are needed.

Domperidone prescribing patterns in pediatric patients before and after safety warning in South Korea

In 2014, the Korean Ministry of Food and Drug Safety (MFDS) issued a safety warning to carefully consider adverse cardiac effects when prescribing domperidone for children. We conducted this study to compare the trends of domperidone prescription in pediatrics before and after the MFDS safety warning. This study included patients < 18 years old who used national health insurance services within the year 2011 and the year 2016, sampled from Health Insurance Review Agency data. We analyzed domperidone prescribing patterns including prescribed daily dosage, maximum period of continuous prescription, and number and types of co-prescribed medications and compared two different years pre and post safety warning. A total of 16,614 pediatric patients (1.74%) received domperidone prescriptions in 2011, and 11,317 patients (1.23%) in 2016. The probability of receiving at least one prescription in 2016 has been reduced by 30% compared to 2011. Gastritis was the most common indication in both years. The number of prescriptions containing a maximum daily dosage of over 30 mg was significantly lower in 2016. In the same time period, the number of cases with a maximum continuous prescription period of more than 7 days significantly decreased (p<0.001). In addition, from 2011 to 2016, comorbid diseases of domperidone-treated patients were similar, but the number of co-prescriptions of interacting medication to domperidone decreased (p<0.001). After the 2014 safety letter was released, the pattern of prescribing domperidone in pediatrics has enhanced drug safety for children in terms of frequency of prescriptions, maximum duration of domperidone use, and the prescription of drugs interacting with domperidone.

Atopic Disease and Anemia in Korean Patients: Cross-Sectional Study with Propensity Score Analysis.

Atopic disease is associated with chronic inflammation, and anemia has been reported in patients with inflammatory disorders such as rheumatoid arthritis, chronic obstructive pulmonary disease, and irritable bowel disease. The objective of this study was to determine whether atopic disease is associated with an increased risk of anemia. A cross-sectional study with propensity score weighting was conducted using a health insurance review agency claims dataset comprised of randomized patients who used the Korean national health system at least once in 2016. The association between atopic disease (asthma, atopic dermatitis, allergic rhinitis) and anemia (iron deficiency anemia (IDA) and/or anemia of inflammation (AI)) was examined. A total of 1,468,033 patients were included in this study. The IDA/AI prevalence was 3.1% (45,681 patients). After propensity score weighting, there were 46,958 and 45,681 patients in the non-anemic and anemic groups, respectively. The prevalence of IDA/AI in patients with atopic dermatitis, allergic rhinitis, or asthma had an odds ratio (OR) of 1.40 (95% confidence interval (CI), 1.33–1.48; p < 0.001), 1.17 (95% CI, 1.14–1.21; p < 0.001), and 1.32 (95% CI, 1.28–1.36; p < 0.001), respectively. In addition, the prevalence of IDA increased with higher numbers of atopic diseases. In conclusion, the prevalence of IDA/AI was higher in patients with atopic disease, even after adjusting for demographic characteristics and other risk factors. Further study is needed to distinguish between IDA and AI and to enhance understanding of the etiology of anemia in patients with inflammatory conditions.

Continuation of schizophrenia treatment with three long-acting injectable antipsychotics in South Korea: A nationwide population-based study

Long-acting injectable (LAI) antipsychotics have been developed to prevent symptom relapse in patients with schizophrenia; relapse has a detrimental clinical impact and high social burden. However, data on treatment continuation rates of LAI antipsychotics are inconsistent, primarily because of study design; limited data exist for patients taking oral psychotropic medications taken along with LAI antipsychotics, and factors related to LAI antipsychotics treatment discontinuation. Patients with schizophrenia in the South Korea Health Insurance Review Agency database from 2007 to 2016 who had received LAI haloperidol, LAI paliperidone, or LAI risperidone were included. Treatment continuation rates and proportions of patients using concurrent oral psychotropic medications were calculated. Cox proportional hazard ratios were used for analysis related to discontinuation. There was a significant difference in treatment continuation rates at 6 months after initiation (36.8% LAI haloperidol, 57.5% LAI paliperidone, and 34.5% LAI risperidone). A substantial proportion of patients in all three groups were prescribed oral antipsychotics during LAI antipsychotics treatment. In the LAI paliperidone group, type of hospital was significantly associated with a higher risk of treatment discontinuation, with a hazard ratio of 1.195–1.598. Early discontinuation of LAI antipsychotic treatment occurs in a large number of patients with schizophrenia. Intervention strategies for improving the LAI antipsychotics treatment adherence are needed.

Trends in the prevalence and incidence of ankylosing spondylitis in South Korea, 2010\u20132015 and estimated differences according to income status

The aim of this study is to determine the prevalence and incidence of ankylosing spondylitis (AS) in South Korea, 2010–2015. This study was conducted using the Health Insurance Review Agency (HIRA) database, which includes information on every patient diagnosed with AS. The incidence and prevalence of AS were evaluated by age, sex, and income status. The prevalence increased linearly by 7.7% annually, i.e., 31.62 in 2010 to 52.30 in 2015 (per 100,000 persons). During the study period, the incidence was 6.34 per 100,000 person-years. The prevalence peaked for both men and women in the age range 30–39 years. Incidence peaked for men in the age range 20–29 years, but peaked for women between ages 70 and 89. AS was 3.6 times more prevalent in men than in women, and the incidence in men was 2.1 times greater than in women. With respect to income status, the prevalence and incidence of AS were 3 times greater and 5 times greater, respectively, in medical aid recipients compared to individuals with other income levels. The trend of increasing AS prevalence and the observation that 14.3% of all patients newly diagnosed with AS are medical aid recipients have significant implications for healthcare planning.

Perception and attitude of Korean physicians towards generic drugs

BackgroundIn 2012, a new pharmaceutical policy was introduced in Korea. According to the new policy, off-patent brand-name drugs (original drugs) and generic drugs must be priced the same.MethodsThis study aims to investigate the perception and attitude of Korean physicians towards generic drugs before and after the policy reform. Surveys were conducted with registered doctors at the Health Insurance Review Agency (HIRA) twice, in 2011 and 2013, by means of email and HIRA online survey systems.ResultsIn the 2011 survey, 82% knew about the bioequivalent (BE) guideline, whereas only 25.7% trusted BE testing results. More than half preferred original drugs to generic drugs because of clinical experience and generic drugs confidence limits. 64.2% pointed out that the Korean generic drugs prices are more expensive than in other counties. In the 2013 survey, 73% preferred original drugs to generic drugs because of believed difference in drug effectiveness. After the pricing policy reform, 35.5% stated that they didn’t change their prescribing pattern, whereas 29.7% stated that they began prescribing generic drugs.ConclusionsThe Korean government has revised and strengthen the guideline on BE test to improve the quality and confidence of generic drugs. Although generic drugs prescription was increased slightly more than the 2011 survey, 2013 survey showed that around 70% of respondents still preferred original drugs.