Comparison of partitioned survival modeling with state transition modeling approaches with or without consideration of brain metastasis: a case study of Osimertinib versus pemetrexed-platinum.

BACKGROUND: The partitioned survival model (PSM) and the state transition model (STM) are widely used in cost-effectiveness analyses of anticancer drugs. Using different modeling approaches with or without consideration of brain metastasis, we compared the quality-adjusted life-year (QALY) estimates of Osimertinib and pemetrexed-platinum in advanced non-small cell lung cancer with epidermal growth factor receptor mutations. METHODS: We constructed three economic models using parametric curves fitted to patient-level data from the National Health Insurance Review and Assessment claims database from 2009 to 2020. PSM and 3-health state transition model (3-STM) consist of three health states: progression-free, post-progression, and death. The 5-health state transition model (5-STM) has two additional health states (brain metastasis with continuing initial therapy, and with subsequent therapy). Time-dependent transition probabilities were calculated in the state transition models. The incremental life-year (LY) and QALY between the Osimertinib and pemetrexed-platinum cohorts for each modeling approach were estimated over seven years. RESULTS: The PSM and 3-STM produced similar incremental LY (0.889 and 0.899, respectively) and QALY (0.827 and 0.840, respectively). However, 5-STM, which considered brain metastasis as separate health states, yielded a slightly higher incremental LY (0.910) but lower incremental QALY (0.695) than PSM and 3-STM. CONCLUSIONS: Our findings indicate that incorporating additional health states such as brain metastases into economic models can have a considerable impact on incremental QALY estimates. To ensure appropriate health technology assessment decisions, comparison and justification of different modeling approaches are recommended in the economic evaluation of anticancer drugs.

Survival differences between patients with de novo and relapsed/progressed advanced non-small cell lung cancer without epidermal growth factor receptor mutations or anaplastic lymphoma kinase rearrangements.

BACKGROUND: We aimed to examine whether patients with de novo and relapsed/progressed stage IIIB-IV non-small cell lung cancer (NSCLC) without epidermal growth factor receptor (EGFR) or anaplastic lymphoma kinase (ALK) mutations have different prognoses. METHODS: This retrospective study analyzed the Health Insurance Review and Assessment claims data in South Korea from 2013 to 2020. Patients with stage IIIB-IV NSCLC without EGFR or ALK mutations who received first-line palliative therapy between 2015 and 2019 were identified. Overall survival (OS), time to first subsequent therapy (TFST), and time to second subsequent therapy (TSST) were estimated using the Kaplan-Meier method. Multivariate Cox regression analysis was used to reveal the impact of de novo versus relapsed/progressed disease on OS. Treatment patterns, including treatment sequence, top five most frequent regimens, and time to treatment discontinuation, were described in both groups. RESULTS: Of 14,505 patients, 12,811 (88.3%) were de novo, and 1,694 (11.7%) were relapsed/progressed. The median OS in the de novo group was 11.0 versus 11.5 months in the relapsed/progressed group (P = 0.002). The ongoing treatment probability was higher in relapsed/progressed patients than in de novo patients from 6.4 months since the initiation of first-line treatment (P < 0.001). Median TSST was shorter in the de novo group than in the relapsed/progressed group (9.5 vs. 9.9 months, P < 0.001). In multivariate analysis, de novo disease was associated with shorter OS (hazard ratio 1.07; 95% confidence interval 1.01-1.14). The overall treatment patterns for de novo and relapsed/progressed patients were similar. CONCLUSIONS: De novo patients had poorer OS and TSST after the initiation of palliative therapy than relapsed/progressed patients. These findings suggest that the stage of the disease at the time of initial diagnosis should be considered in observational studies and clinical trials as a prognostic factor.

Factors influencing drug switching and changes in low-density lipoprotein-cholesterol levels with atorvastatin: a real-world observational study.

BACKGROUND: Although generic drugs have been approved with the assurance of interchangeable applications with original drugs, some physicians, and patients still view their efficacy and interchangeability negatively. Using real-world data, we aimed to determine factors that impact switching between drugs that contain the same active ingredient, i.e., atorvastatin, and, in turn, whether this 'switch' could alter clinical outcomes. METHODS: Using the National Health Insurance Service senior cohort, a retrospective cohort study was conducted to assess patients who had newly started atorvastatin 10 mg and had at least two records of national health examinations from 2010 to 2014. Drug switching, which was defined as a change in the atorvastatin product administered 90 days before the first and second examinations, was assessed. Greedy propensity score matching (1:2) was performed between switchers and non-switchers to control for potential confounders. Factors influencing switching were analyzed using multivariate logistic regression to estimate odds ratios and 95% confidence intervals (CIs). Changes in low-density lipoprotein-cholesterol (LDL-C) levels attributable to drug switching were evaluated using difference-in-differences regression. RESULTS: A total of 1,588 patients were included, of whom 25.3% switched drugs (1,187 non-switchers and 401 switchers). Compared to patients taking generics before the first examination, those taking the original drugs had a lower odds ratio (0.31; 95% CI [0.21, 0.46]) for subsequent drug switching. A change in medical institution was associated with a significantly higher odds ratio (6.83; 95% CI [4.66, 10.02]). There were no significant differences in LDL-C alterations between switchers and non-switchers (0.42 mg/dL; 95% CI [-2.29, 3.13]). CONCLUSION: The type of first-time drug administered and changes in medical institution can influence drug switching. No significant changes in LDL-C values were observed in the various switching scenarios between the original and generic drugs, suggesting their interchangeable application in real-world clinical practice.

Cost-Effectiveness Analysis of Smoking Cessation Interventions With Behavioral Support: A Study Based on the Benefits of Smoking Cessation on Outcomes (BENESCO) Model.

INTRODUCTION: Few studies have compared cost-effectiveness of different smoking cessation interventions (SCIs) that include behavioral support, considering smoking-related diseases. Therefore, we compare the cost-effectiveness of SCIs with behavioral support in South Korea using the Benefits of Smoking Cessation on Outcomes (BENESCO) model. AIMS AND METHODS: We used the BENESCO model to estimate the cost and utility of the SCIs with behavioral support, including pharmacist counseling with nicotine replacement therapy (pharmacist+NRT), expert counseling with NRT (expert+NRT), and expert counseling with varenicline (expert+varenicline). The target population was adult smokers who wanted to cease smoking within 1 month. We applied transitional probabilities and epidemiological data from the literature. Medical costs and utilities were calculated using claims and national survey data, respectively. Cost-effectiveness was evaluated within the threshold (17 926 USD per quality-adjusted life years [QALYs]) by incremental cost-effectiveness ratio (ICER). RESULTS: The model cohort included 1 219 390 male and 298 511 female smokers. The pharmacist+NRT group had 32 842 more QALYs gained and 26 689 958 USD less expended than the expert+NRT group. The ICER for the expert+varenicline group versus the pharmacist+NRT and expert+NRT groups was 27 247 and 4074 USD per QALY, respectively. The robustness of the results was confirmed by sensitivity analyses, except for the discount rate and cost of the expert+varenicline group. CONCLUSIONS: In Korea, pharmacist counseling with NRT showed higher QALY gains and lower costs than expert counseling with NRT. Expert counseling with varenicline was more effective for smoking cessation and more cost-effective than expert counseling with NRT but was not cost-effective compared with pharmacist counseling with NRT. IMPLICATIONS: This study provides evidence for decision-making on smoking cessation programs by evaluating the cost-effectiveness of SCIs. Furthermore, we attempted to use the BENESCO model to compare and evaluate the cost-effectiveness of SCIs with behavioral support. It is meaningful because this study showed the availability of using the BENESCO model in the future cost-effectiveness analysis of various SCIs.

Importance of a usual source of care in choosing low-priced generic drugs: a cross-sectional study.

BACKGROUND: The potential to lower pharmaceutical spending exists if physicians prescribe low-priced generics. This study aimed to empirically investigate the determinants of choosing low-priced generic drugs in South Korea. METHODS: The 2018 HIRA-NPS dataset was used for this study. Among 1.45 million individuals, we identified the patients who were prescribed atorvastatin 10 mg for more than 60 days in 2018 as the study subjects, separated the subjects into high- and low-priced groups based on their average unit price, and applied a series of logistic regression models to elucidate the factors affecting low-priced drug choice. RESULTS: Out of 60,984 subjects, only 10,228 (17%) were categorized into the low-priced group. The majority of the subjects (31%) were prescribed drugs at the maximum reimbursement price. Age of the subject, the frequency of visits to the institution, the existence of a usual source of care, and the institution type that a subject mainly visited for prescriptions were associated with being prescribed low-priced generics. CONCLUSION: The association of being prescribed low-priced generics with the primary care institution and the usual source of care could be interpreted as evidence for the role of primary care in the continuity of patient-centred care. Creating health systems under which professionals act as perfect agents of a patient and/or an insurer is required.

Generic drugs with a discounted price compared to their corresponding brand-name drugs could be prescribed for patients. Therefore, spending on pharmaceuticals could be saved if physicians prescribed low-priced generics and/or patients switched from high-priced drugs to low-priced drugs. Policymakers have introduced several ways to encourage choosing low-priced generic drugs. This study focussed on the factors associated with choosing low-priced generic drugs in South Korea. Contrary to our expectations, only a few patients (17% of the total patients) choose low-priced generics, indicating potential to save pharmaceutical expenditure. Geriatric patients, patients who mainly visited primary healthcare institutions, and patients who had a usual source of care were more likely to choose low-priced generics. This study also suggested various ways to encourage choosing low-priced generic drugs in health systems.

Cost-effectiveness of antiviral treatment in adult patients with immune-tolerant phase chronic hepatitis B.

OBJECTIVE: The cost-effectiveness of antiviral treatment in adult immune-tolerant (IT) phase chronic hepatitis B (CHB) patients is uncertain. DESIGN: We designed a Markov model to compare expected costs and quality-adjusted life-years (QALYs) of starting antiviral treatment at IT-phase ('treat-IT') vs delaying the therapy until active hepatitis phase ('untreat-IT') in CHB patients over a 20-year horizon. A cohort of 10 000 non-cirrhotic 35-year-old patients in IT-phase CHB (hepatitis B e antigen-positive, mean serum hepatitis B virus (HBV) DNA levels 7.6 log10 IU/mL, and normal alanine aminotransferase levels) was simulated. Input parameters were obtained from previous studies at Asan Medical Center, Korea. The incremental cost-effectiveness ratio (ICER) between the treat-IT and untreat-IT strategies was calculated. RESULTS: From a healthcare system perspective, the treat-IT strategy with entecavir or tenofovir had an ICER of US$16 516/QALY, with an annual hepatocellular carcinoma (HCC) incidence of 0.73% in the untreat-IT group. With the annual HCC risk ≥0.54%, the treat-IT strategy was cost-effective at a willingness-to-pay threshold of US$20 000/QALY. From a societal perspective considering productivity loss by premature death, the treat-IT strategy was extremely cost-effective, and was dominant (ICER <0) if the HCC risk was ≥0.43%, suggesting that the treat-IT strategy incurs less costs than the untreat-IT strategy. The most influential parameters on cost-effectiveness of the treat-IT strategy were those related with HCC risk (HBV DNA levels, platelet counts and age) and drug cost. CONCLUSION: Starting antiviral therapy in IT phase is cost-effective compared with delaying the treatment until the active hepatitis phase in CHB patients, especially with increasing HCC risk, decreasing drug costs and consideration of productivity loss.

Therapeutic efficacy of new botulinum toxin identified in CCUG 7968 strain.

Botulinum neurotoxin type A (BoNT/A) induces muscle atrophy by cleaving synaptosomal-associated protein 25. Thus, BoNT/A has been actively utilized for the treatment of masseter and gastrocnemius hypertrophy. In this study, INI101 toxin was newly identified from the CCUG 7968 strain, and its therapeutic efficacy was evaluated both in vitro and in vivo. The INI101 toxin showed identical genetic sequence, amino acid sequence, and protein subunit composition to BoNT/A produced from strain Hall A. Electromyography (EMG), and immunofluorescence staining demonstrated that INI101 (at 2 ~ 8 U/rat) effectively blocked the neuromuscular junction with no toxicity in a rat model. The EMG results showed INI101 toxin-induced weight loss and volume reduction of the gastrocnemius, similar to the effects of Botox® (BTX). Histological and immunofluorescence staining was consistent with this EMG result, showing that INI101 toxin caused muscle fiber reduction in the gastrocnemius. Notably, INI101 toxin diffused less into adjacent muscle tissue than BTX, indicating that INI101 toxin may reduce potential side effects due to diffusion into normal tissues. INI101 toxin isolated from the novel strain CCUG 7968 is a newly identified meaningful biopharmaceutical comparable to the conventional BoNT/A in the medical field. KEY POINTS: • Botulinum neurotoxin type A (BoNT/A, INI101) was identified from the CCUG 7968 strain. • INI101 toxin showed similar safety and therapeutic efficacy comparable to conventional BoNT/A both in vitro and in vivo. • INI101 toxin is a meaningful biopharmaceutical comparable to the conventional BoNT/A in the medical field.

Magnetic Resonance Imaging Is Cost-Effective for Hepatocellular Carcinoma Surveillance in High-Risk Patients With Cirrhosis.

Ultrasonography (US) is generally recommended for the surveillance of hepatocellular carcinoma (HCC) in patients at risk. However, in patients with cirrhosis who have sufficiently high HCC incidence, surveillance using magnetic resonance imaging (MRI) with liver-specific contrast showed markedly higher sensitivity in detecting early-stage HCC than US. This study aimed to compare the cost-effectiveness of semiannual surveillance using MRI versus US in patients with compensated cirrhosis and to identify the population that would gain optimal cost-effectiveness through MRI surveillance. We designed a Markov model to compare the expected costs and quality-adjusted life-years (QALYs), between MRI and US, with a 20-year time horizon, from the health care system perspective. The starting age of the cohort was 50 years, and 71% had hepatitis B virus-associated cirrhosis. The cycle length was 6 months. Transition probabilities and costs were obtained mainly from a prospective cohort study (the PRIUS study, NCT01446666). Cost and effectiveness were discounted at 5%. An incremental cost-effectiveness ratio (ICER) was calculated and tested using sensitivity analyses. The cost-effectiveness analysis indicated that the use of MRI incurred $5,562 incremental costs, 0.384 incremental life-years (LYs), and 0.221 incremental QALYs compared to US. The annual HCC incidence was the most influential factor on the ICER. The ICERs were $14,474/LY and $25,202/QALY at an annual HCC incidence of 3%. When the HCC incidence rate was >1.81%, the ICER was below $50,000/QALY. With increased HCC incidence, MRI surveillance was acceptable as a cost-effective option, even with an increased MRI/US cost ratio. Conclusion: Semiannual surveillance using MRI with liver-specific contrast may be more cost-effective than US in patients with virus-associated compensated cirrhosis at sufficiently high HCC risk despite the higher test cost of MRI.

Risk of neuropsychiatric adverse events associated with the use of oseltamivir: a nationwide population-based case-crossover study.

Background: Although the potential risk of neuropsychiatric adverse events (NPAEs) upon administration of oseltamivir has been raised in case reports, the association between the use of oseltamivir and the risk of NPAEs is unclear. Objectives: We aimed to evaluate whether the use of oseltamivir triggers NPAEs. Patients and methods: We conducted a population-based case-crossover study using the National Sample Cohort data from the National Health Insurance Service in South Korea. From a total of 236 348 incident patients with NPAEs as either a primary or secondary diagnosis, our final case series included 5322 patients with a prior prescription for oseltamivir between 2009 and 2013. Exposure to oseltamivir was assessed during 2, 7, 14, 28 and 56 day hazard periods prior to each patient's NPAE. Three pre-consecutive control periods were matched using the same time windows. Conditional logistic regression analysis was used to estimate adjusted ORs (aORs), adjusting for time-variant diagnosis of influenza and concomitant medications. Results: Matched analyses found a consistently increased risk of NPAEs associated with the use of oseltamivir in the 2 day (aOR 1.90, 95% CI 1.29-2.81), 7 day (aOR 1.32, 95% CI 1.00-1.74), 14 day (aOR 1.28, 95% CI 1.03-1.60), 28 day (aOR 1.25, 95% CI 1.06-1.47) and 56 day (aOR 1.13, 95% CI 0.99-1.29) hazard periods compared with use in the three control periods. Conclusions: This study found that the short-term use of oseltamivir triggers the incidence of NPAEs. Early monitoring of NPAEs may be required when prescribing oseltamivir with careful consideration of the risk-benefit balance of oseltamivir.

Differences in the risk of mood disorders in patients with asthma-COPD overlap and in patients with COPD alone: a nationwide population-based retrospective cohort study in Korea.

BACKGROUND: Although feelings of anxiety and depression are common in patients with chronic obstructive pulmonary disease (COPD), little is known about the estimates of their incidence in patients with asthma-COPD overlap (ACO), which has been described and acknowledged as a distinct clinical entity. We aimed to estimate the risk of depression and anxiety among patients with ACO and compare it with the risk among those with COPD alone in the general population. METHODS: We conducted a nationwide population-based retrospective cohort study using the Korean National Sample Cohort database between 1 January, 2002, and 31 December, 2013. Patients who were diagnosed with COPD (International Classification of Diseases, 10th revision [ICD-10] codes J42-J44) at least twice and prescribed COPD medications at least once between 2003 and 2011 were classified into two categories: patients who were diagnosed with asthma (ICD-10 codes J45-J46) more than twice and at least once prescribed asthma medications comprised the ACO group, and the remaining COPD patients comprised the COPD alone group. Patients who had been diagnosed with depression or anxiety within a year before the index date were excluded. We defined the outcome as time to first diagnosis with depression and anxiety. Matched Cox regression models were used to compare the risk of depression and anxiety among patients with ACO and patients with COPD alone after propensity score matching with a 1:1 ratio. RESULTS: After propensity score estimation and matching in a 1:1 ratio, the cohort used in the analysis included 15,644 patients. The risk of depression during the entire study period was higher for patients with ACO than for patients with COPD alone (adjusted hazard ratio, 1.10; 95% confidence interval, 1.03-1.18; P value = 0.0039), with an elevated risk in patients aged 40-64 years (1.21; 1.10-1.34; 0.0001) and in women (1.18; 1.07-1.29; 0.0005). The risk of anxiety was higher for patients with ACO than for patients with COPD alone (1.06; 1.01-1.12; 0.0272), with a higher risk in patients aged 40-64 years (1.08; 1.00-1.17; 0.0392); however, the risk was not significant when stratified by sex. CONCLUSIONS: This population-based study revealed a higher incidence of depression and anxiety in patients with ACO than in patients with COPD alone.

Beyond uncertainty: Negative findings for the association between the use of proton pump inhibitors and risk of dementia.

OBJECTIVES: We investigated the risk of dementia associated with the use of proton pump inhibitors (PPIs) as compared with the use of histamine-2 receptor antagonist (H2RA). METHODS: We conducted retrospective propensity score-matched cohort study using the National Health Insurance Service-National Sample Cohort. Subjects were defined as the patients newly prescribed with PPI or H2RA between 2003 and 2013 without prior prescriptions of PPI/H2RA or diagnosis of dementia from their history within the past 1 year. We followed up participants until dementia occurrence, death, or the end of the study, whichever occurred first, with an intention-to-treat approach. A 1-year lag time between exposure and outcome measure was used to reduce protopathic bias. The incidence rate per 1000 person-years was estimated. The incidence rate of PPI was compared with that of H2RA, defined as incidence rate ratio (IRR), calculated with a 95% confidence interval. To control for potential confounds, propensity score matching at a 1:1 ratio was conducted, and the crude IRR was adjusted by risk factors. RESULTS: Our propensity score-matched cohort included 87 562 patients on PPIs and 87 562 patients on H2RAs. The IRR was 1.01 (95% confidence interval 0.96-1.06) with 1-year lag time. IRR showed the decreased trend as the longer lag time. Also, no treatment duration or dose-response relationship was observed. CONCLUSIONS: Our finding demonstrated that PPIs did not associate with dementia more strongly than did H2RA. On this basis, we suggest that the previously reported risk for dementia associated with PPI may have been overestimated.

Proton-pump inhibitors and the risk of Clostridium difficile-associated diarrhea in high-risk antibiotics users: A population-based case-crossover study.

PURPOSE: Given the severity and high-costs demand of Clostridium difficile-associated diarrhea (CDAD), management of risk factors is very important. Although the association between proton-pump inhibitors (PPIs) and CDAD has been established, little is known among high-risk antibiotics users. This study aimed to identify the association between PPIs and CDAD in high-risk antibiotics users by using a case-crossover design. METHODS: We conducted a case-crossover study using a nationwide population-based cohort in South Korea. Participants who developed CDAD from 1 January 2003 to 31 December 2013 and had prior prescription records of both PPIs and high-risk antibiotics were included. The hazard period was 49 days, and the three prior control periods had the same duration as the hazard period. The status of exposure to PPIs was assessed during the hazard and control periods in each patient and discordant pairs of exposure were used to estimate the matched odds ratio (OR). RESULTS: In total, 200 participants with CDAD who had histories of both PPIs and high-risk antibiotics use were included. A twofold increased risk for CDAD due to PPI use was observed (OR = 2.0; 95% confidence interval, 1.2-3.2). The time-invariant variables including age group, sex, and comorbidities were proven not to modify the association between PPIs and CDAD. CONCLUSIONS: Our study suggested that PPIs increase the risk of developing CDAD in high-risk antibiotics users. Thus, PPIs should be used cautiously in patients requiring high-risk antibiotics in the situation of medical treatment to prevent further incidence of CDAD.

Current status of pharmacovigilance regulatory structures, processes, and outcomes in the Asia-Pacific region: Survey results from 15 countries.

PURPOSE: Regulatory discrepancies may exist in pharmacovigilance (PV) structure, process, and outcome status worldwide. Our study's objective was to survey the current status of PV in each regulatory body in the Asia-Pacific Economic Cooperation (APEC) region. METHODS: A modified questionnaire was sent to the PV team heads of 21 PV agencies based in the APEC countries, between June 28 and September 12, 2017, to gather information on the structure, process, and outcome of PV status in these countries. RESULTS: Of the 21 APEC countries, 15 responded. We found harmonized laws and regulations for general PV and risk management systems. However, variations were found in PV structure: for example, 11 out of 15 countries had national regulatory representatives responsible for PV in pharmaceutical companies, while four did not. For PV process, discrepancies were also found in the source type of adverse drug reaction (ADR) reports and reporting of medication errors and therapeutic ineffectiveness in cumulative ADR reports. With respect to PV outcomes, among countries that performed active surveillance, the United States of America was more active, with hundreds of projects including additional pharmacoepidemiological studies etc. Among the nine countries that responded, Japan had the greatest number of product label changes followed by Taiwan, Malaysia, and Korea. CONCLUSION: We have identified substantial variations in the structures, processes, and outcomes of PV status among the countries of the APEC region. Therefore, efforts to reduce variations in the PV administration and regulation are warranted for harmonization of PV within the APEC region.

Gastrointestinal risk of non-steroidal anti-inflammatory drugs and gastroprotective agents used in the treatment of osteoarthritis in elderly patients: A nationwide retrospective cohort study
.

OBJECTIVE: Osteoarthritis is highly prevalent in older adults and often treated with nonsteroidal anti-inflammatory drugs (NSAIDs). COX-2-selective NSAIDs have been shown to offer better gastrointestinal (GI) safety benefits than non-selective NSAIDs (ns-NSAIDs). However, most COX-2-selective NSAIDs have not been comprehensively evaluated for use in combination with gastroprotective agents (GPAs). This study compared the risk of adverse GI events in patients treated with COX-2-selective NSAIDs and ns-NSAIDs alone, or in combination with GPAs. MATERIALS AND METHODS: We utilized National Health Insurance Claim Data collected from 2012 to 2015. Newly diagnosed patients with osteoarthritis (60 years or older) were included in this study. The study population was divided into two groups: 1) COX-2-selective NSAID treatment and 2) ns-NSAIDs treatment. Patients were followed-up for up to 6 months to determine whether GI events occurred. The Cox proportional hazards model was used to identify differences in risk. Subgroup analyses were conducted for monotherapies and combination treatments with GPAs. RESULTS: The number of subjects prescribed COX-2-selective NSAID and ns-NSAIDs were 20,868 (5.6%) and 353,494 (94.4%), respectively. After adjustment for confounding factors, COX-2-selective NSAID were safer than ns-NSAIDs (adjusted hazard ratio (aHR) = 0.80, 95% confidence interval (CI): 0.77 - 0.82). Use of GPAs with COX-2-selective NSAID was associated with a lower risk of GI events than use of ns-NSAIDs (aHR = 0.92, 95% CI: 0.87 - 0.97). CONCLUSION: Use of COX-2-selective NSAID was associated with a lower risk of GI adverse events than use of ns-NSAIDs as a monotherapy. Furthermore, COX-2-selective NSAID were safer than ns-NSAIDs in combination with GPAs.
.

Regulatory effect of decreasing therapeutic duplication of respiratory drugs using a prescription database between 2012 and 2015.

Duplicative drug use increases the risk of adverse drug reactions and expends healthcare resources unnecessarily. No epidemiological evidence of the prevalence of therapeutic duplication (TD) involving respiratory system drugs exists. Therefore, we describe the prescription patterns of these drugs and estimate changes in TD rates following implementation of a new regulation in 2013. A time-series analysis using national healthcare data was conducted, involving eight classes, and patients prescribed any of these drugs between 2012 and 2015. We used two definitions of TD; duplicative prescriptions overlapped for more than 30 days by the same prescriber and for more than 1 day by different prescribers. We calculated relative and absolute difference in TD rates after the regulation. TD by the same prescriber decreased for respiratory drugs of six classes, but increased more than 10% for antihistamines (+10.28, +0.05). TD by a different prescriber decreased only for xanthine bronchodilators, but increased more than 10% for beta-receptor agonists (+27.07, +1.42), leukotriene receptor antagonists (+16.10, +0.44), cough suppressants (+15.64, +0.52), mucolytic agents (+11.16, +0.67). The 2013 regulation regarding respiratory drugs did not have the anticipated effect of reducing TD prevalence; more effective interventions are needed.

Prevalence and predictors of tricyclic antidepressant use among elderly Koreans in primary-care and specialty clinics.

OBJECTIVES: Tricyclic antidepressants (TCAs) are prescribed with caution in the elderly due to diverse side effects. We analyzed the patterns of TCA use in elderly patients in primary-care and specialty clinics and investigated factors influencing TCA prescriptions. MATERIALS AND METHODS: Elderly patients (≥ 65 years old) prescribed antidepressants in primary-care clinics in 2013 were included from the Health Insurance Review and Assessment Service-Aged Patient Sample (HIRA-APS). Prevalence of TCA prescriptions was assessed by insurance coverage status, clinical specialty, and region. Multiple logistic regression analysis was performed to compute odds ratios (ORs) and 95% confidence intervals (CIs) for factors associated with TCA prescriptions. RESULTS: TCAs and selective serotonin reuptake inhibitors (SSRIs) comprised 45.2% and 15.0% of all antidepressant prescriptions, respectively. TCAs comprised 61.5% and 20.7% of antidepressant prescriptions for pain and depression, respectively. Patients aged ≥ 85 years were less likely to be treated with TCAs (OR 0.81, 95% CI 0.79 - 0.84) than those aged 65 - 69 years. The odds for being prescribed TCAs were higher for patients residing in cities (OR 1.20, 95% CI 1.18 - 1.23), treated in nonpsychiatric clinics (OR 5.64, 95% CI 5.53 - 5.76), and those covered by Veteran's Health (OR 1.62, 95% CI 1.37 - 1.90) when compared to patients residing in the Seoul metropolitan area, treated in psychiatric clinics, or covered by National Health Insurance, respectively. The prescriptions of TCAs with pain diagnoses were much higher than prescriptions for depression (OR 1.87, 95% CI 1.82 - 1.93). CONCLUSIONS: Compared with a 2005 report, the prevalence of TCA prescriptions in elderly patients in Korea has decreased substantially, but remains high. Various efforts should be considered to reduce TCA prescriptions in the elderly.
.

Projection of future pharmacy service fees using the dispensing claims in hospital and clinic outpatient pharmacies: national health insurance database between 2006 and 2012.

BACKGROUND: Predicting pharmacy service fees is crucial to sustain the health insurance budget and maintain pharmacy management. However, there is no evidence on how to predict pharmacy service fees at the population level. This study compares the status of pharmacy services and constructs regression model to project annual pharmacy service fees in Korea. METHODS: We conducted a time-series analysis by using sample data from the national health insurance database from 2006 and 2012. To reflect the latest trend, we categorized pharmacies into general hospital, special hospital, and clinic outpatient pharmacies based on the major source of service fees, using a 1% sample of the 2012 data. We estimated the daily number of prescriptions, pharmacy service fees, and drugs costs according to these three types of pharmacy services. To forecast pharmacy service fees, a regression model was constructed to estimate annual fees in the following year (2013). The dependent variable was pharmacy service fees and the independent variables were the number of prescriptions and service fees per pharmacy, ratio of patients (≥ 65 years), conversion factor, change of policy, and types of pharmacy services. RESULTS: Among the 21,283 pharmacies identified, 5.0% (1064), 4.6% (974), and 77.5% (16,340) were general hospital, special hospital, and clinic outpatient pharmacies, respectively, in 2012. General hospital pharmacies showed a higher daily number of prescriptions (111.9), higher pharmacy service fees ($25,546,342), and higher annual drugs costs ($215,728,000) per pharmacy than any other pharmacy (p <  0.05). The regression model to project found the ratio of patients aged 65 years and older and the conversion factor to be associated with an increase in pharmacy service fees. It also estimated the future rate of increase in pharmacy service fees to be between 3.1% and 7.8%. CONCLUSIONS: General hospital outpatient pharmacies spent more on annual pharmacy service fees than any other type of pharmacy. The forecast of annual pharmacy service fees in Korea was similar to that of Australia, but not that of the United Kingdom.

A comparison of discontinuation rates of tofacitinib and biologic disease-modifying anti-rheumatic drugs in rheumatoid arthritis: a systematic review and Bayesian network meta-analysis.

OBJECTIVES: The purpose of this study was to compare the discontinuation rates of tofacitinib and biologics (tumour necrosis factor inhibitors (TNFi), abatacept, rituximab, and tocilizumab) in rheumatoid arthritis (RA) patients considering inadequate responses (IRs) to previous treatment(s). METHODS: Randomised controlled trials of tofacitinib and biologics - reporting at least one total discontinuation, discontinuation due to lack of efficacy (LOE), and discontinuation due to adverse events (AEs) - were identified through systematic review. The analyses were conducted for patients with IRs to conventional synthetic disease-modifying anti-rheumatic drugs (cDMARDs) and for patients with biologics-IR, separately. Bayesian network meta-analysis was used to estimate rate ratio (RR) of a biologic relative to tofacitinib with 95% credible interval (CrI), and probability of RR being <1 (P[RR<1]). RESULTS: The analyses of 34 studies showed no significant differences in discontinuation rates between tofacitinib and biologics in the cDMARDs-IR group. In the biologics-IR group, however, TNFi (RR 0.17, 95% CrI 0.01-3.61, P[RR<1] 92.0%) and rituximab (RR 0.20, 95% CrI 0.01-2.91, P[RR<1] 92.3%) showed significantly lower total discontinuation rates than tofacitinib did. Despite the difference, discontinuation cases owing to LOE and AEs revealed that tofacitinib was comparable to the biologics. CONCLUSIONS: The comparability of discontinuation rate between tofacitinib and biologics was different based on previous treatments and discontinuation reasons: LOE, AEs, and total (due to other reasons). Therefore, those factors need to be considered to decide the optimal treatment strategy.

Selenium-binding protein 1: a sensitive urinary biomarker to detect heavy metal-induced nephrotoxicity.

Identifying novel biomarkers to detect nephrotoxicity is clinically important. Here, we attempted to identify new biomarkers for mercury-induced nephrotoxicity and compared their sensitivity to that of traditional biomarkers in animal models. Comparative proteomics analysis was performed in kidney tissues of Sprague-Dawley rats after oral treatment with HgCl2 (0.1, 1, or 5 mg/kg/day) for 21 days. Kidney cortex tissues were analyzed by two-dimensional gel electrophoresis/matrix-assisted laser desorption/ionization, and differentially expressed proteins were identified. The corresponding spots were quantitated by RT-PCR. Selenium-binding protein 1 (SBP1) was found to be the most markedly upregulated protein in the kidney cortex of rats after HgCl2 administration. However, blood urea nitrogen, serum creatinine, and glucose levels increased significantly only in the 1 or 5 mg/kg HgCl2-treated groups. A number of urinary excretion proteins, including kidney injury molecule-1, clusterin, monocyte chemoattractant protein-1, and ß-microglobulin, increased dose-dependently. Histopathological examination revealed severe proximal tubular damage in high-dose (5 mg/kg) HgCl2-exposed groups. In addition, urinary excretion of SBP1 significantly increased in a dose-dependent manner. To confirm the critical role of SBP1 as a biomarker for nephrotoxicity, normal kidney proximal tubular cells were treated with HgCl2, CdCl2, or cisplatin for 24 h. SBP1 levels significantly increased in conditioned media exposed to nephrotoxicants, but decreased in cell lysates. Our investigations suggest that SBP1 may play a critical role in the pathological processes underlying chemical-induced nephrotoxicity. Thus, urinary excretion of SBP1 might be a sensitive and specific biomarker to detect early stages of kidney injury.

Comparison of first- and second-generation antihistamine prescribing in elderly outpatients: A health insurance database study in 2013.

BACKGROUND: This descriptive study analyzed the scale of first- and second-generation antihistamine prescription in elderly outpatients in Korea and the characteristics associated with this prescription. MATERIALS AND METHODS: We conducted a drug utilization study using the Korea Health Insurance Review and Assessment Service-Aged Patient Sample (HIRA-APS) database from January 1 to December 31, 2013. The study subjects were elderly outpatients aged 65 years and older who were prescribed antihistamines. The study drugs included 6 first-generation and 16 second-generation antihistamines. The prescription pattern of first-generation antihistamines was based on region, diagnosis, and clinical specialty. Multivariate logistic regression analysis was used to determine the factors associated with first-generation antihistamine prescription. Odds ratios (ORs) with 95% confidence interval (CI) were calculated. RESULTS: A total of 1,152,556 elderly outpatients were identified as having visited various medical facilities in 2013, of which 23.4% received at least one prescription for first-generation antihistamine monotherapy. First-generation antihistamines were more likely to be prescribed in secondary care hospitals (OR = 1.74; 95% CI 1.69 - 1.78) than in tertiary care hospitals, and in urban areas (OR = 1.21; 95% CI 1.20 - 1.21) than in the Seoul metropolitan area. First-generation antihistamines were also more likely to be prescribed for treating the common cold (OR = 1.06; 95% CI 1.05 - 1.06) than any other disease. CONCLUSION: A large proportion (23.4%) of elderly outpatients in Korea received prescriptions for first-generation antihistamines. Efforts to reduce prescriptions of first-generation antihistamines are recommended, especially prescriptions associated with common cold diagnosis in secondary care hospitals and in urban areas.
.