Identification of Drugs and Patient Profiles at Risk for Severe Skin Injuries Due to Extravasation: Analysis of a Spontaneous Reporting System.

This study aimed to identify risk factors and combinations thereof that are associated with severe skin injuries due to the extravasation of injectable drugs. A cross-sectional study using the Japanese Adverse Drug Event Report database was conducted according to the RECORD-PE checklist. Adverse event reports related to necrosis, ulcers, or erosions due to extravasation were considered "with severe skin injury," and others were considered "without severe skin injury." Approximately 255 cases "with" and 260 cases "without" severe skin injury were identified. The relationship between the incidence of severe skin injury and age, sex, drugs, and primary disease was evaluated using the χ2 test. Association rule mining was used to evaluate the correlation between each combination of factors and skin injury. Nine factors were identified as independent risk factors for severe skin injury, including age (<10 or ≥70 years), peripheral parenteral nutrition use, and mental disorders. The association rule mining results suggested that a combination of specific patient backgrounds and drug use was associated with the incidence of necrosis or ulcers. The findings of this study reiterate that nurses might consider closely observing patients with the risk factors identified in this study for the prevention and early detection of extravasation-related skin injuries.

Performance of cone-beam computed tomography imaging during megavoltage beam irradiation under phase-gated conditions.

PURPOSE: Target positions should be acquired during beam delivery for accurate lung stereotactic body radiotherapy. We aimed to perform kilovoltage (kV) imaging during beam irradiation (intra-irradiation imaging) under phase-gated conditions and evaluate its performance. METHODS: Catphan 504 and QUASAR respiratory motion phantoms were used to evaluate image quality and target detectability, respectively. TrueBeam STx linac and the Developer Mode was used. The imaging parameters were 125 kVp and 1.2 mAs/projection. Flattened megavoltage (MV) X-ray beam energies 6, 10 and 15 MV and un-flattened beam energies 6 and 10 MV were used with field sizes of 5 × 5 and 15 × 15 cm2 and various frame rates for intra-irradiation imaging. In addition, using a QUASAR phantom, intra-irradiation imaging was performed during intensity-modulated plan delivery. The root-mean-square error (RMSE) of the CT-number for the inserted rods, image noise, visual assessment, and contrast-to-noise ratio (CNR) were evaluated. RESULTS: The RMSEs of intra-irradiation cone-beam computed tomography (CBCT) images under gated conditions were 50-230 Hounsfield Unit (HU) (static < 30 HU). The noise of the intra-irradiation CBCT images under gated conditions was 15-35 HU, whereas that of the standard CBCT images was 8.8-27.2 HU. Lower frame rates exhibited large RMSEs and noise; however, the iterative reconstruction algorithm (IR) was effective at improving these values. Approximately 7 fps with the IR showed an equivalent CNR of 15 fps without the IR. The target was visible on all the gated intra-irradiation CBCT images. CONCLUSION: Several image quality improvements are required; however, intra-irradiated CBCT images showed good visual target detection.

Morita Therapy as a Treatment Approach for Adolescent Autism Spectrum Disorder: A Five-Year Case Report Incorporating Inpatient and Diary Therapy.

In 1919, Shoma Morita established Morita therapy, and this method of psychotherapy is widely used in Japan and across the world. With time, the medical indications of Morita therapy have expanded to include not only neurosis and anxiety disorders but other conditions as well. In modern times, Morita therapy has been used to treat adolescentneurodevelopmental disorders; however, it has not been widely covered in the English-language literature. In this report, a five-year course of treatment for a female patient with autism spectrum disorder (ASD) is presented. The patient exhibited dissociation, auditory hallucinations, overmedication, and wrist cutting, leading to multiple admissions to an adolescent ward. Over the treatment course, the symptoms of dissociation, self-harm, and auditory hallucinations disappear. Further, the patient was able to find a way to relate to society that was appropriate for her.

Unifying gamma passing rates in patient-specific QA for VMAT lung cancer treatment based on data assimilation.

This study aimed to identify systematic errors in measurement-, calculation-, and prediction-based patient-specific quality assurance (PSQA) methods for volumetric modulated arc therapy (VMAT) on lung cancer and to standardize the gamma passing rate (GPR) by considering systematic errors during data assimilation. This study included 150 patients with lung cancer who underwent VMAT. VMAT plans were generated using a collapsed-cone algorithm. For measurement-based PSQA, ArcCHECK was employed. For calculation-based PSQA, Acuros XB was used to recalculate the plans. In prediction-based PSQA, GPR was forecasted using a previously developed GPR prediction model. The representative GPR value was estimated using the least-squares method from the three PSQA methods for each original plan. The unified GPR was computed by adjusting the original GPR to account for systematic errors. The range of limits of agreement (LoA) were assessed for the original and unified GPRs based on the representative GPR using Bland-Altman plots. For GPR (3%/2 mm), original GPRs were 94.4 ± 3.5%, 98.6 ± 2.2% and 93.3 ± 3.4% for measurement-, calculation-, and prediction-based PSQA methods and the representative GPR was 95.5 ± 2.0%. Unified GPRs were 95.3 ± 2.8%, 95.4 ± 3.5% and 95.4 ± 3.1% for measurement-, calculation-, and prediction-based PSQA methods, respectively. The range of LoA decreased from 12.8% for the original GPR to 9.5% for the unified GPR across all three PSQA methods. The study evaluated unified GPRs that corrected for systematic errors. Proposing unified criteria for PSQA can enhance safety regardless of the methods used.

Applications of artificial intelligence for machine- and patient-specific quality assurance in radiation therapy: current status and future directions.

Machine- and patient-specific quality assurance (QA) is essential to ensure the safety and accuracy of radiotherapy. QA methods have become complex, especially in high-precision radiotherapy such as intensity-modulated radiation therapy (IMRT) and volumetric modulated arc therapy (VMAT), and various recommendations have been reported by AAPM Task Groups. With the widespread use of IMRT and VMAT, there is an emerging demand for increased operational efficiency. Artificial intelligence (AI) technology is quickly growing in various fields owing to advancements in computers and technology. In the radiotherapy treatment process, AI has led to the development of various techniques for automated segmentation and planning, thereby significantly enhancing treatment efficiency. Many new applications using AI have been reported for machine- and patient-specific QA, such as predicting machine beam data or gamma passing rates for IMRT or VMAT plans. Additionally, these applied technologies are being developed for multicenter studies. In the current review article, AI application techniques in machine- and patient-specific QA have been organized and future directions are discussed. This review presents the learning process and the latest knowledge on machine- and patient-specific QA. Moreover, it contributes to the understanding of the current status and discusses the future directions of machine- and patient-specific QA.

Relationships between acute generalized eruptive pustulosis, age, sex, primary disease, and prescription medications: Further analysis of the Japanese Adverse Drug Event Report database.

Background: Acute generalized eruptive pustulosis (AGEP) is a rare, but serious, drug-related adverse event. This study aimed to determine the relationships between AGEP and age, sex, primary disease, and prescription medications using a database of adverse drug events, namely, the Japanese Adverse Drug Event Report (JADER) database. Methods: In this retrospective observational study, we analyzed AGEP reports extracted from the JADER database based on the preferred term for AGEP (code 10048799). We evaluated the effects of causative drugs, underlying diseases, age, and sex. The association between AGEP and prescription drugs was analyzed using the reporting odds ratio and adjusted for covariates using multiple logistic regression. Association rule mining was performed to evaluate the correlation between each combination of factors and AGEP. Results: Between April 2004 and March 2023, 823,662 reports, including 869 reports on AGEP, were entered in the JADER database. The highest percentage of reports in each age group was in males aged <10 years, and clarithromycin was the most used drug in males aged <10 years. Nasopharyngitis was the most common reason for use, and Kawasaki disease was reported as a reason for use among males under 10 years of age, but not among females. Conclusions: In boys aged <10 years, attention should be paid to the occurrence of AGEP when prescribing clarithromycin and treating Kawasaki disease.

Protocol of a phase II study to evaluate the efficacy and safety of deep-inspiration breath-hold daily online adaptive radiotherapy for centrally located lung tumours (PUDDING study).

BACKGROUND: Centrally located lung tumours present a challenge because of their tendency to exhibit symptoms such as airway obstruction, atelectasis, and bleeding. Surgical resection of these tumours often requires sacrificing the lungs, making definitive radiotherapy the preferred alternative to avoid pneumonectomy. However, the proximity of these tumours to mediastinal organs at risk increases the potential for severe adverse events. To mitigate this risk, we propose a dual-method approach: deep inspiration breath-hold (DIBH) radiotherapy combined with adaptive radiotherapy. The aim of this single-centre, single-arm phase II study is to investigate the efficacy and safety of DIBH daily online adaptive radiotherapy. METHODS: Patients diagnosed with centrally located lung tumours according to the International Association for the Study of Lung Cancer recommendations, are enrolled and subjected to DIBH daily online adaptive radiotherapy. The primary endpoint is the one-year cumulative incidence of grade 3 or more severe adverse events, as classified by the Common Terminology Criteria for Adverse Events (CTCAE v5.0). DISCUSSION: Delivering definitive radiotherapy for centrally located lung tumours presents a dilemma between ensuring optimal dose coverage for the planning target volume and the associated increased risk of adverse events. DIBH provides measurable dosimetric benefits by increasing the normal lung volume and distancing the tumour from critical mediastinal organs at risk, leading to reduced toxicity. DIBH adaptive radiotherapy has been proposed as an adjunct treatment option for abdominal and pelvic cancers. If the application of DIBH adaptive radiotherapy to centrally located lung tumours proves successful, this approach could shape future phase III trials and offer novel perspectives in lung tumour radiotherapy. TRIAL REGISTRATION: Registered at the Japan Registry of Clinical Trials (jRCT; https://jrct.niph.go.jp/ ); registration number: jRCT1052230085 ( https://jrct.niph.go.jp/en-latest-detail/jRCT1052230085 ).

Analysis of drug-induced interstitial lung disease caused by herbal medicine using the Japanese Adverse Drug Event Report database.

BACKGROUND: Drug-induced interstitial lung disease (DIILD) is a severe adverse event leading to morbidity and mortality. This study evaluated the adverse event indicators of DIILD and time-to-onset profiles following the daily intake of herbal drugs (Scutellariae radix ["ogon" in Japanese], Bupleuri radix ["saiko" in Japanese], and Pinelliae tuber ["hange" in Japanese]) using the Japanese Adverse Drug Event Report database. DIILD was defined in accordance with the Medical Dictionary for Regulatory Activities. METHODS: The Japanese Adverse Drug Event Report database contained 830,079 reports published between April 2004 and April 2023. The association between herbal medicines and DILLD was evaluated using the pharmacovigilance index as the reporting odds ratio (ROR), logistic regression models, propensity score-matching techniques, and Weibull shape parameters. RESULTS: The adjusted RORs using multivariate logistic regression models for Scutellariae radix (daily intake), Pinelliae tuber (daily intake), sex (male), age (≥ 60 years), Scutellariae radix (daily intake)*age (≥ 60 years), and Scutellariae radix (daily intake)* Pinelliae tuber (daily intake) were 1.47 (1.36 - 1.59), 1.05 (1.01 - 1.10), 1.45 (1.34 - 1.57), 1.92 (1.74 - 2.11), 3.35 (3.12 - 3.60), and 1.49 (1.46 - 1.53), respectively. DIILD onset profiles were evaluated using the Weibull shape parameter. A logistic plot of daily intake and onset of DIILD was drawn. ROR signals were detected in 32 of 54 herbal medicines, including Scutellariae radix, Bupleuri radix, and Pinelliae tuber. The median duration (days) (interquartile range) to DIILD onset was 36.0 (27.0-63.0) for Saikokaryukotsuboreito, 35.0 (21.0-55.0) for Saireito, and 31.0 (13.5-67.5) for Shosaikoto. The Weibull shape parameter beta (95% confidence interval) values for Saikokaryukotsuboreito, Saireito, and Shosaikoto were 1.36 (1.08-1.67), 1.36 (1.20-1.52), and 1.31 (0.98-1.68), respectively. CONCLUSIONS: DIILD demonstrated a dose-dependent to crude drugs. Clinicians should strive for the early detection of DIILD and avoid the inadvertent administration of herbal medicines.

Survey of community and hospital pharmacist involvement in outpatient chemotherapy using Japanese health information data.

In this study, information on injectable anticancer drug use and additional fee for enhanced collaboration (AEC) and additional fee for specific drug management guidance 2 (ASD2) claims from the NDB Open Data Japan (NODJ) dataset and the number of patients with cancer according to sex and age from the National Cancer Registry (NCR) dataset were integrated and evaluated to determine the current status and challenges in pharmacist interventions for patients receiving cancer treatment. The NODJ data, including receipt data billed from 2020 to 2021, were obtained from the Ministry of Health, Labour and Welfare website. The use of injectable anticancer drugs decreased relative to the number of cancer patients aged ≥ 75 years compared to those aged < 75 years. Regarding injectable anticancer drug use, the number of AEC claims was similar between men and women, but the number of ASD2 claims was lower in men than in women. The number of times community pharmacists claimed their ASD2 was approximately 5% of the number of times hospital pharmacists claimed their AEC. This study revealed that several patients did not receive sufficient guidance from community pharmacists compared to hospital pharmacists, suggesting a potential insufficiency in the collaboration between the two groups.

Influence of dose calculation algorithms on the helical diode array using volumetric-modulated arc therapy for small targets.

BACKGROUND: For patient-specific quality assurance (PSQA) for small targets, the dose resolution can change depending on the characteristics of the dose calculation algorithms. PURPOSE: This study aimed to evaluate the influence of the dose calculation algorithms Acuros XB (AXB), anisotropic analytical algorithm (AAA), photon Monte Carlo (pMC), and collapsed cone (CC) on a helical diode array using volumetric-modulated arc therapy (VMAT) for small targets. MATERIALS AND METHODS: ArcCHECK detectors were inserted with a physical depth of 2.9 cm from the surface. To evaluate the influence of the dose calculation algorithms for small targets, rectangular fields of 2×100, 5×100, 10×100, 20×100, 50×100, and 100×100 mm2 were irradiated and measured using ArcCHECK with TrueBeam STx. A total of 20 VMAT plans for small targets, including the clinical sites of 19 brain metastases and one spine, were also evaluated. The gamma passing rates (GPRs) were evaluated for the rectangular fields and the 20 VMAT plans using AXB, AAA, pMC, and CC. RESULTS: For rectangular fields of 2×100 and 5×100 mm2 , the GPR at 3%/2 mm of AXB was < 50% because AXB resulted in a coarser dose resolution with narrow beams. For field sizes > 10×100 mm2, the GPR at 3%/2 mm was > 88.1% and comparable for all dose calculation algorithms. For the 20 VMAT plans, the GPRs at 3%/2 mm were 79.1 ± 15.7%, 93.2 ± 5.8%, 94.9 ± 4.1%, and 94.5 ± 4.1% for AXB, AAA, pMC, and CC, respectively. CONCLUSION: The behavior of the dose distribution on the helical diode array differed depending on the dose calculation algorithm for small targets. Measurements using ArcCHECK for VMAT with small targets can have lower GPRs owing to the coarse dose resolution of AXB around the detector area.

Relationship between the Number of Pharmacists per Pharmacy and the Provision of Home Healthcare Services in Japan.

Home healthcare services provided by community pharmacists are essential for maintaining community care, especially in Japan's aging population. Personnel shortage in pharmacies is occasionally cited as the reason why pharmacies are unable to provide home healthcare services. This study examined the relationship between the number of pharmacists in each pharmacy and the provision of home healthcare services. The number of full-time and part-time pharmacists per pharmacy has a positive impact on the provision of home healthcare services. Moreover, the larger the number of pharmacists per pharmacy, the easier it is for the pharmacy to provide home healthcare services. With regard to pharmacies with one full-time pharmacist, there are more pharmacies that provide home healthcare services when the population density of municipalities where the pharmacy is located is high. However, the impact of the number of pharmacists on population density became obscure when the number of full-time pharmacists per pharmacy was three or more. Taken together, these findings indicate that the provision of home healthcare services by pharmacies is related to the number of pharmacists per pharmacy and the population density of the area. This could have implications for widening regional disparities in home healthcare services.

Population-based asymmetric margins for moving targets in real-time tumor tracking.

BACKGROUND: Both geometric and dosimetric components are commonly considered when determining the margin for planning target volume (PTV). As dose distribution is shaped by controlling beam aperture in peripheral dose prescription and dose-escalated simultaneously integrated boost techniques, adjusting the margin by incorporating the variable dosimetric component into the PTV margin is inappropriate; therefore, geometric components should be accurately estimated for margin calculations. PURPOSE: We introduced an asymmetric margin-calculation theory using the guide to the expression of uncertainty in measurement (GUM) and intra-fractional motion. The margins in fiducial marker-based real-time tumor tracking (RTTT) for lung, liver, and pancreatic cancers were calculated and were then evaluated using Monte Carlo (MC) simulations. METHODS: A total of 74 705, 73 235, and 164 968 sets of intra- and inter-fractional positional data were analyzed for 48 lung, 48 liver, and 25 pancreatic cancer patients, respectively, in RTTT clinical trials. The 2.5th and 97.5th percentiles of the positional error were considered representative values of each fraction of the disease site. The population-based statistics of the probability distributions of these representative positional errors (PD-RPEs) were calculated in six directions. A margin covering 95% of the population was calculated using the proposed formula. The content rate in which the clinical target volume (CTV) was included in the PTV was calculated through MC simulations using the PD-RPEs. RESULTS: The margins required for RTTT were at most 6.2, 4.6, and 3.9 mm for lung, liver, and pancreatic cancer, respectively. MC simulations revealed that the median content rates using the proposed margins satisfied 95% for lung and liver cancers and 93% for pancreatic cancer, closer to the expected rates than the margins according to van Herk's formula. CONCLUSIONS: Our proposed formula based on the GUM and motion probability distributions (MPD) accurately calculated the practical margin size for fiducial marker-based RTTT. This was verified through MC simulations.

Organ-contour-driven auto-matching algorithm in image-guided radiotherapy.

PURPOSE: This study aimed to demonstrate the potential clinical applicability of an organ-contour-driven auto-matching algorithm in image-guided radiotherapy. METHODS: This study included eleven consecutive patients with cervical cancer who underwent radiotherapy in 23 or 25 fractions. Daily and reference magnetic resonance images were converted into mesh models. A weight-based algorithm was implemented to optimize the distance between the mesh model vertices and surface of the reference model during the positioning process. Within the cost function, weight parameters were employed to prioritize specific organs for positioning. In this study, three scenarios with different weight parameters were prepared. The optimal translation and rotation values for the cervix and uterus were determined based on the calculated translations alone or in combination with rotations, with a rotation limit of ±3°. Subsequently, the coverage probabilities of the following two planning target volumes (PTV), an isotropic 5 mm and anisotropic margins derived from a previous study, were evaluated. RESULTS: The percentage of translations exceeding 10 mm varied from 9% to 18% depending on the scenario. For small PTV sizes, more than 80% of all fractions had a coverage of 80% or higher. In contrast, for large PTV sizes, more than 90% of all fractions had a coverage of 95% or higher. The difference between the median coverage with translational positioning alone and that with both translational and rotational positioning was 1% or less. CONCLUSION: This algorithm facilitates quantitative positioning by utilizing a cost function that prioritizes organs for positioning. Consequently, consistent displacement values were algorithmically generated. This study also revealed that the impact of rotational corrections, limited to ±3°, on PTV coverage was minimal.

Dosimetric verification of four dose calculation algorithms for spine stereotactic body radiotherapy.

The applications of Type B [anisotropic analytical algorithm (AAA) and collapsed cone (CC)] and Type C [Acuros XB (AXB) and photon Monte Carlo (PMC)] dose calculation algorithms in spine stereotactic body radiotherapy (SBRT) were evaluated. Water- and bone-equivalent phantoms were combined to evaluate the percentage depth dose and dose profile. Subsequently, 48 consecutive patients with clinical spine SBRT plans were evaluated. All treatment plans were created using AXB in Eclipse. The prescription dose was 24 Gy in two fractions at a 10 MV FFF on TrueBeam. The doses were then recalculated with AAA, CC and PMC while maintaining the AXB-calculated monitor units and beam arrangement. The dose index values obtained using the four dose calculation algorithms were then compared. The AXB and PMC dose distributions agreed with the bone-equivalent phantom measurements (within ±2.0%); the AAA and CC values were higher than those in the bone-equivalent phantom region. For the spine SBRT plans, PMC, AAA and CC were overestimated compared with AXB in terms of the near minimum and maximum doses of the target and organ at risk, respectively; the mean dose difference was within 4.2%, which is equivalent with within 1 Gy. The phantom study showed that the results from AXB and PMC agreed with the measurements within ±2.0%. However, the mean dose difference ranged from 0.5 to 1 Gy in the spine SBRT planning study when the dose calculation algorithms changed. Users should incorporate a clinical introduction that includes an awareness of these differences.

CT number calibration audit in photon radiation therapy.

BACKGROUND: Inadequate computed tomography (CT) number calibration curves affect dose calculation accuracy. Although CT number calibration curves registered in treatment planning systems (TPSs) should be consistent with human tissues, it is unclear whether adequate CT number calibration is performed because CT number calibration curves have not been assessed for various types of CT number calibration phantoms and TPSs. PURPOSE: The purpose of this study was to investigate CT number calibration curves for mass density (ρ) and relative electron density (ρe ). METHODS: A CT number calibration audit phantom was sent to 24 Japanese photon therapy institutes from the evaluating institute and scanned using their individual clinical CT scan protocols. The CT images of the audit phantom and institute-specific CT number calibration curves were submitted to the evaluating institute for analyzing the calibration curves registered in the TPSs at the participating institutes. The institute-specific CT number calibration curves were created using commercial phantom (Gammex, Gammex Inc., Middleton, WI, USA) or CIRS phantom (Computerized Imaging Reference Systems, Inc., Norfolk, VA, USA)). At the evaluating institute, theoretical CT number calibration curves were created using a stoichiometric CT number calibration method based on the CT image, and the institute-specific CT number calibration curves were compared with the theoretical calibration curve. Differences in ρ and ρe over the multiple points on the curve (Δρm and Δρe,m , respectively) were calculated for each CT number, categorized for each phantom vendor and TPS, and evaluated for three tissue types: lung, soft tissues, and bones. In particular, the CT-ρ calibration curves for Tomotherapy TPSs (ACCURAY, Sunnyvale, CA, USA) were categorized separately from the Gammex CT-ρ calibration curves because the available tissue-equivalent materials (TEMs) were limited by the manufacturer recommendations. In addition, the differences in ρ and ρe for the specific TEMs (ΔρTEM and Δρe,TEM , respectively) were calculated by subtracting the ρ or ρe of the TEMs from the theoretical CT-ρ or CT-ρe calibration curve. RESULTS: The mean ± standard deviation (SD) of Δρm and Δρe,m for the Gammex phantom were -1.1 ± 1.2 g/cm3 and -0.2 ± 1.1, -0.3 ± 0.9 g/cm3 and 0.8 ± 1.3, and -0.9 ± 1.3 g/cm3 and 1.0 ± 1.5 for lung, soft tissues, and bones, respectively. The mean ± SD of Δρm and Δρe,m for the CIRS phantom were 0.3 ± 0.8 g/cm3 and 0.9 ± 0.9, 0.6 ± 0.6 g/cm3 and 1.4 ± 0.8, and 0.2 ± 0.5 g/cm3 and 1.6 ± 0.5 for lung, soft tissues, and bones, respectively. The mean ± SD of Δρm for Tomotherapy TPSs was 2.1 ± 1.4 g/cm3 for soft tissues, which is larger than those for other TPSs. The mean ± SD of Δρe,TEM for the Gammex brain phantom (BRN-SR2) was -1.8 ± 0.4, implying that the tissue equivalency of the BRN-SR2 plug was slightly inferior to that of other plugs. CONCLUSIONS: Latent deviations between human tissues and TEMs were found by comparing the CT number calibration curves of the various institutes.

Construction of Shape Atlas for Abdominal Organs using Three-Dimensional Mesh Variational Autoencoder.

A model that represents the shapes and positions of organs or skeletal structures with a small number of parameters may be expected to have a wide range of clinical applications, such as radiotherapy and surgical guidance. However, because soft organs vary in shape and position between patients, it is difficult for linear models to reconstruct locally variable shapes, and nonlinear models are prone to overfitting, particularly when the quantity of data is small. The aim of this study was to construct a shape atlas with high accuracy and good generalization performance. We designed a mesh variational autoencoder that can reconstruct both nonlinear shape and position with high accuracy. We validated the trained model for liver meshes of 125 cases, and found that it was possible to reconstruct the positions and shapes with an average accuracy of 4.3 mm for the test data of 19 cases.

Study of Factors to Increase the Usage Rate of Generic Drugs in Platelet Aggregation Inhibitors.

To reduce pharmacy-related medical expenses, it is necessary to reduce drug costs. One way to achieve this is by increasing the usage rate of generic drugs. The purpose of this study was to identify platelet aggregation inhibitors (PAIs) that contribute to high drug costs and are sold as brand-name drugs in order to increase the usage rate of generic drugs, and to analyze the factors that affect the usage rate of generic drug. We conducted a cross-sectional study based on the National Database of Health Insurance Claims and Specific Health Checkups of Japan Open Data Japan (NODJ) of the Ministry of Health, Labor and Welfare and datasets containing related medical information from official statistical surveys such as the Basic Survey on Wage Structure. Monthly personal income in each prefecture were negatively correlated with outpatient out-of-hospital and outpatient in-hospital prescriptions of the PAIs clopidogrel (75 mg), cilostazol (50 mg), cilostazol (100 mg), and ticlopidine (100 mg), but not between monthly personal income and outpatient out-of-hospital prescription of ticlopidine (100 mg). For outpatient out-of-hospital prescriptions and outpatient in-hospital prescriptions, negative correlation was generally observed between the usage rate of generic drug and monthly personal income, except for ticlopidine (100 mg), which has the lowest price among the brand-name drugs. The usage rate of generic PAIs is negatively correlated with monthly personal income. Promoting the use of generic drugs among high-income earners might be necessary to further increase the usage rate of generic drug.

Progressive multifocal leukoencephalopathy analyzed using the Japanese Adverse Drug Event Report database.

BACKGROUND: Progressive multifocal leukoencephalopathy (PML) has been reported as the development of drugs with immunomodulatory properties, such as anticancer, immunosuppressive, and biological agents, has accelerated. To clarify an incidence profile of drug-associated PML in real-world clinical practice, we analyzed reported patients with PML using the Japanese Adverse Drug Event Report (JADER) database. METHODS: We analyzed PML reports extracted from the JADER database based on the preferred term of "progressive multifocal leukoencephalopathy" from between 2004 and 2021. This was a retrospective, observational study. We evaluated the effects of causative drugs, underlying diseases, and the age of the patients on the annual number of PML reports. RESULTS: The JADER database contained 773,966 reports published between April 2004 and March 2022, from which we identified 361 PML events. These PML events may include multiple counts of the same case reported by different pathways and patients diagnosed with probable or possible PML. The number of PML reports and reporting ratios have gradually increased over the past decade. The annual number of PML reports associated with biologics, immunosuppressants, and antineoplastic drugs showed an increasing trend. Females aged ≥30 years showed an increase in PML reports; in contrast, there the number of reports for males aged ≥50 years increased. CONCLUSIONS: The number of PML reports and reporting ratios have gradually increased in the past decade in Japan, and it considered that it was related to change in the treatment of malignancies and autoimmune diseases, and the increasing use of biologics, immunosuppressive agents, and antineoplastic agents.