Self-controlled Case Series Study for Acute Kidney Injury after Starting Proton Pump Inhibitors or Potassium-Competitive Acid Blocker in Patients with Cancer Using a Large Claims Database.

To investigate the risk of acute kidney injury (AKI) in patients with cancer following the initiation of proton pump inhibitors (PPIs) and potassium-competitive acid blocker (PCAB), considering sex and anti-cancer drug use. We conducted a self-controlled case-series study using the Japan Medical Data Center claims data from 12422 patients with cancer who were prescribed PPIs or PCAB between January 2017 and December 2019. Considering the timing of PPI or PCAB, control period (days -120 to -1), risk period 1 (days 0 to +30), and risk period 2 (days +31 to +365) were defined. To assess the incidence rate ratio (IRR) and 95% confidence interval (CI) as the risk ratio, we adjusted for anti-cancer drugs to assess the risk of AKI. Additionally, we also examined sex differences to identify the risk of AKI. AKI was observed in risk period 1 [2.05 (1.12-3.72), p = 0.0192], but a slight reduction was noted in risk period 2 [0.60 (0.36-1.00), p = 0.0481]. A sex-specific increase in the risk of AKI was observed only in males during risk period 1 [2.18 (1.10-4.32), p = 0.0260], with a reduction in risk period 2 [0.48 (0.26-0.89), p = 0.0200]. We identified an increased risk of AKI in patients with cancer starting PPIs or PCAB particularly in males within 30 d after PPI or PCAB initiation, emphasizing the need for vigilant monitoring and management of AKI in this patient population.

Retrospective analysis of atlantoaxial rotatory fixation describing age distribution and gender ratio in children and adolescents: A preliminary report.

INTRODUCTION: Atlantoaxial rotatory fixation (AARF) in children presents with an acute onset of neck pain. Almost all cases heal within a few days of onset and are treated conservatively. Because few cases of AARF have been reported, the age distribution or gender ratio of AARF in the child population have not been described enough. In Japan, the social insurance system covers all citizens. Thus, we used insurance claims data to investigate the features of AARF. The aim of this study is to examine the age distribution, compare gender ratio and determine the recurrence proportion of AARF. METHODS: We used the JMDC database to search for claims data submitted between January 2005 and June 2017 for cases of AARF in patients aged <20 years. RESULTS: We identified 1949 patients with AARF, of which 1102 (56.5%) were male. The mean age was 98.3 ± 42.2 months and 91.6 ± 38.4 months in males and females, respectively, and males with AARF were significantly older at onset than females with AARF (p < 0.001). In both sexes, the highest frequency of AARF occurred when the patient was 6 years old. There were 121 (6.2%) cases of recurrent AARF (male: 61, 5.5%; female: 60, 7.1%), but the age differences between the sexes in these cases were not statistically significant. CONCLUSIONS: This is the first report to describe the characteristics of the study population of AARF. Males were more likely to suffer from AARF than females. Furthermore, age (in months) at AARF onset was significantly higher in males than in females. Recurrence rate was not significant in both sexes.

Assessment of Diagnosis Timing of Attention-Deficit/Hyperactivity Disorder in Working-Age Workers with Psychiatric Diseases Using Large Claims Data.

Attention deficit/hyperactivity disorder (ADHD) is a common developmental disorder. This study aims to clarify the timing of diagnosis of ADHD in working-age workers with psychiatric comorbidities using large claims data in Japan. Based on a literature survey, we identified 10 typical comorbidities of ADHD. Among 3064162 participants with social insurance, 215060 working-age workers who were diagnosed with the 10 typical comorbidities of ADHD were included. Cohort 1 consisted of 96994 patients with the index date set as the earliest date of diagnosis of a comorbidity within the 12-month screening and 12-month observation periods. In cohort 2, 107436 patients were included, and the first date of diagnosis of each comorbidity was used as the index month. In cohort 1, 0.19% of the patients were diagnosed with ADHD after being diagnosed with a typical comorbidity. In cohort 2, 4 out of 4 patients with ADHD and obsessive-compulsive disorders were diagnosis ADHD after obsessive-compulsive disorders. Pervasive developmental disorders were the highest comorbidity of ADHD for 62 out of 566 (11.0%) patients. This is the first study to determine the proportion of ADHD with typical comorbidities in working-age workers in Japan. Our findings highlight the need for timely diagnosis of ADHD to improve patients' QOL.

Risk Assessment for Heart Failure in Patients with Type 2 Diabetes Mellitus Treated with Dipeptidyl Peptidase 4 Inhibitor Using a Large Claims Dataset.

Heart failure is a prevalent comorbidity in patients with diabetes mellitus (DM). However, it is unclear whether the risk factors for heart failure in DM patients treated with dipeptidyl peptidase-4 (DPP-4) inhibitors are the same as those for the general population. In this study, we evaluated the factors of new-onset heart failure in working-age patients with diabetes who started DPP-4 inhibitor therapy. This study included 7938 working-age patients. The primary endpoint of the study was the proportion of patients developing heart failure within 12 months of starting DPP-4 inhibitor therapy, which was found to be 1.89% (n = 150). In these patients, risk factors of new-onset heart failure were aging, history of atrial fibrillation, and hypertension but not sex, smoking, high body mass index, weight gain of over 10 kg from 20 years of age, levels of low-density lipoprotein or glycated hemoglobin A1c (HbA1c), history of angina pectoris, myocardial infarction, and chronic kidney disease. We confirmed that cardiovascular comorbidities are risk factors for new-onset heart failure in patients with DM, while general risk factors are not. In conclusion, physicians and pharmacists need to carefully monitor working-age patients with cardiovascular history who start DPP-4 inhibitor therapy even if they do not exhibit general risk factors for heart failure.

Descriptive Study on a Nationwide Exploratory Questionnaire Survey of Emergency Contraceptive Pills and Their Sexual History and Knowledge in Japan.

A shift towards obtaining emergency contraceptives without a prescription have been discussed in Japan. In response to this social background, we aimed at investigating the background of sexual intercourse, emergency contraceptive use, and knowledge of sexual and reproductive health education among women of reproductive age in Japan. In this study, we conducted a national wide cross-sectional questionnaire survey using a total of 4 web-based domains (background, sexual history, emergency contraceptives, and sexual and reproduction-related knowledge) composed of 50 questions. We obtained responses from a total of 4,631 participants of varying age groups (18-25, 26-35, and 36-45 years old) and 47 prefectures (84 to 118 from each prefecture). Among participant responses, 69.7% are sexually active, of which 49.0% had experiences of sexual intercourse with an unknown person. The responses from a total of 737 participants who have sexual intercourse, know of emergency contraceptives, and have experienced a situation that necessitated the use of emergency contraceptives, were analyzed. Of these participants, 46.4% (342/737) took emergency contraceptives, while 43.6% (321/737) participants did not take emergency contraceptives. Participants who have the knowledge for obtaining emergency contraceptives through the correct means were 52.6% (2438/4631). This study showed that approximately half of participants may not have correct knowledge of emergency contraceptives. In addition, approximately half of sexually active participants are facing unintended pregnancies due to a lack of sexual and reproductive awareness. Hence, comprehensive sex education is necessary to achieve social and regulatory changes centered on emergency contraceptives.

Failure of liposomal amphotericin B therapy in patients with severe pancreatitis complicated by Candida lusitaniae infection.

Candida lusitaniae is an uncommon pathogen that accounts for approximately 1% of patients with candidiasis. In this report, we present the case of a 24-year-old woman with severe pancreatitis who was emergently admitted to Northern Yokohama Hospital. We started treating the pancreatitis and infections according to her culture results. However, her symptoms, accompanied by a necrotic pancreas, did not improve. Finally, C. lusitaniae was detected in the blood and catheter samples. We started antifungal treatment according to the culture results, but the patient died. Generally, the mortality rate for acute pancreatitis ranges from 3% for patients with interstitial edematous pancreatitis to 17% for those who develop pancreatic necrosis. Although we chose appropriate antibiotics and antifungal agents based on the culture results, the treatments failed. Early detection, sufficient doses of antimicrobials and frequent monitoring using sample culture are crucial because infection control may be inadequate, especially in tissues with low blood flow, such as necrotic tissues.

Infliximab Treatment Persistence among Japanese Patients with Chronic Inflammatory Diseases: A Retrospective Japanese Claims Data Study.

Infliximab (IFX) has contributed to the treatment of several chronic inflammatory diseases, including Crohn's disease (CD), ulcerative colitis (UC), psoriasis (Pso), and rheumatoid arthritis (RA). However, the loss of response in some patients with long-term IFX therapy has been a major problem. Randomized controlled trials (RCTs) are limited in their short duration and lack of generalizability to the real-world population. We aimed to describe the persistence rates of IFX therapy to estimate its long-term effectiveness in clinical practice. Claims data from the Japan Medical Data Center database from January 2005 to June 2017 were used. The study population was identified based on the International Classification of Diseases, 10th Revision and the Anatomical Therapeutic Chemical Classification System. The 5-year persistence rates of IFX therapy were estimated using the Kaplan-Meier method. Overall, 281, 235, 41, and 222 patients with CD, UC, Pso, and RA, respectively, were selected. The 5-year persistence rates for IFX claims were 62.9, 38.9, 22.1, and 28.1% in patients with CD, UC, Pso, and RA, respectively. Patients with CD and UC administered IFX beyond the median dose had higher persistence rates. In patients with RA, female sex and no prior use of other biologics were associated with longer persistence. In conclusion, IFX persistence rates differed across chronic inflammatory diseases, which did not correspond to the results of the major RCTs. Factors associated with longer IFX persistence were identified in each disease group. Our findings may provide useful information to facilitate the proper use of IFX.

Identification of the Components of Proton Pump Inhibitors and Potassium-Competitive Acid Blocker That Lead to Cardiovascular Events in Working-Age Individuals: A 12-Month Retrospective Cohort Study Using a Large Claims Database.

This study aimed to identify the components of proton pump inhibitors (PPIs) or potassium-competitive acid blocker (PCAB) that lead to cardiovascular events in individuals of working age. We analyzed large claims data of individuals who were administered PPIs or PCAB. We enrolled working-age individuals administered PPI or PCAB without cardiovascular history with a 12-month screening and 12-month observation period and determined the proportion of cardiovascular events and the predictive factors of cardiovascular events in this population. Among the eligible individuals, 0.5% (456/91098) had cardiovascular events during the 12-month observation period. Predictive factors for cardiovascular events were age for +1 year (p < 0.0001), male sex (p < 0.0001), hypertension (p = 0.0056), and diabetes mellitus (p < 0.0001). The cardiovascular disease risk was higher in working-age individuals administered lansoprazole than in those administered other drugs (vs. rabeprazole; p = 0.0002, vs. omeprazole; p = 0.0046, vs. vonoprazan; p < 0.0001, and vs. esomeprazole; p < 0.0001). We identified the risk for cardiovascular events in individuals being treated with lansoprazole. Lansoprazole is known for its higher CYP2C19 inhibition activity compared with other PPIs or PCAB. A possible mechanism by which lansoprazole may lead to cardiovascular events is inhibiting the generation of epoxyeicosatrienoic acids from arachidonic acids, an intrinsic cardioprotective activator via CYP2C19 inhibition. Thus, we recommend avoiding administering lansoprazole to working-age individuals require PPIs or PCAB.

A Survey of Near-Miss Dispensing Errors in Hospital Pharmacies in Japan: DEPP-J Study-Multi-Center Prospective Observational Study-

The aim of this study was to determine the proportion of near-miss dispensing errors in hospital pharmacies in Japan. A prospective multi-center observational study was conducted between December 2018 and March 2019. The primary objective was to determine the proportion of near-miss dispensing errors in hospital pharmacy departments. The secondary objective was to determine the predictive factors for near-miss dispensing errors using multiple logistic regression analysis. The study was approved by the ethical committee at The Institute of Medical Sciences, University of Tokyo, Japan. A multi-center prospective observational study was conducted in 20 hospitals comprising 8862 beds. Across the 20 hospitals, we assessed data from 553 pharmacists and 53039 prescriptions. A near-miss dispensing error proportion of 0.87% (n = 461) was observed in the study. We found predictive factors for dispensing errors in day-time shifts: a higher number of drugs in a prescription, higher number of quantified drugs, such as liquid or powder formula, in a prescription, and higher number of topical agents in a prescription; but we did not observe for career experience level for clinical pharmacists. For night-time and weekend shifts, we observed a negative correlation of near-miss dispensing errors with clinical pharmacist experience level. We found an overall incidence of near-miss dispensing errors of 0.87%. Predictive factors for errors in night-time and weekend shifts was inexperienced pharmacists. We recommended that pharmacy managers should consider education or improved work flow to avoid near-miss dispensing errors by younger pharmacists, especially those working night or weekend shifts.

Effects of piperacillin/tazobactam or cefepime on folinate dose in patients receiving high-dose methotrexate: A retrospective cohort study using Japanese administrative claims data.

INTRODUCTION: Delayed methotrexate (MTX) clearance with the co-administration of piperacillin/tazobactam (PIPC/TAZ) has been reported. Penicillins have been associated with reduced MTX clearance but the evidence is limited. There are no cases described with cefepime but penicillins are listed as interacting with MTX. We aimed to reveal whether the co-administration of PIPC/TAZ or CFPM affects MTX clearance using data from an administrative database. METHODS: We used data from the JMDC database, a large insurance claims database constructed in Japan. We included patients who were prescribed PIPC/TAZ or CFPM between days 1 and 3 in high-dose MTX (HD-MTX). We compared one co-administration episode (with PIPC/TAZ or CFPM) to one control episode (without), as a match-control study of two different episodes in the same patient. The primary outcomes were the duration and cumulative dose of leucovorin (LV) as a surrogate indicator of delayed MTX clearance. RESULTS: Three patients who were co-administered PIPC/TAZ and 16 patients who were co-administered CFPM with HD-MTX were included. In the PIPC/TAZ group, the duration and the cumulative doses of LV were similar in co-administration and control episode (median 3.0 vs. 3.0 days and 288.0 vs. 219.0 mg). In the CFPM group, the duration and the cumulative doses of LV were not significantly different in co-administration and control episode (3.0 vs. 4.0 days and 169.5 vs. 258.0 mg). CONCLUSIONS: Our findings revealed that PIPC/TAZ did not necessarily cause a delay in MTX clearance during HD-MTX therapy. Moreover, the co-administration of CFPM with HD-MTX did not affect MTX clearance.

Simple determination of urine cefazolin concentration in pediatric patients with urinary tract infections using high-performance liquid chromatography.

Recently, global health concerns regarding increasing multidrug resistance have arisen. This study aimed to develop a simple, inexpensive and rapid high-performance liquid chromatography-ultraviolet (HPLC-UV) method for determining urinary concentrations of a first-generation cephem antibiotic in pediatric patients with urinary tract infections (UTIs). HPLC-UV was used to analyze urinary cefazolin concentrations at a detection wavelength of 254 nm. The assay used contained 10-fold diluted urine with an internal standard (cephapirin). The standard calibration curve for cefazolin was linear in the concentration range of 31.25-500 µg/ml (r2  > 0.999). The retention times of cefazolin and the internal standard were 4.2 and 4.9 min, respectively. The within- and between-day coefficients of variation were in the concentration ranges 1.2-15.2 and 5.5-19.2%, respectively. The urinary cefazolin concentration of a pediatric patient with a UTI was 1,476.6 µg/ml, which was over 700-fold higher than the minimum inhibitory concentration of cefazolin (≤2 µg/ml). The developed method is applicable to the confirmation of appropriate use for UTI treatment as therapeutic drug monitoring of cefazolin. Therefore, the findings of this study may contribute to the appropriate use of antibiotics to prevent antimicrobial resistance in pediatric patients with UTIs.

Probiotic Prescription Status of Pediatric Patients with Otitis Media Receiving Oral Amoxicillin or Amoxicillin/Clavulanate from April 2016 to March 2017 Using a Japanese Health Insurance Claims Database.

Antibiotic-associated diarrhea (AAD) is a typical side effect of antibiotic treatment, especially in children. Amoxicillin (AMPC) and amoxicillin/clavulanate (AMPC/CVA) are associated with high risk of AAD; however, these antibiotics are important in the pediatric field. Recent research suggests that probiotics prevent pediatric AAD, including that caused by AMPC and AMPC/CVA. Indeed, guidelines for acute otitis media in children recommend the concomitant use of probiotics. However, the prescription status of probiotics for pediatric patients with otitis media receiving oral AMPC and AMPC/CVA remains unknown. We therefore conducted a survey to clarify the current status of these prescriptions and, in particular, to identify specific populations with a low proportion of probiotic prescriptions. Pediatric patients (≤15 years of age) newly prescribed oral AMPC or AMPC/CVA for otitis media between April 2016 and March 2017 were identified from a Japanese health insurance claims database. Eligible patients were divided into the AMPC (1303 patients) and AMPC/CVA (424 patients) groups, in which 659 (50.6%) and 293 (69.1%) patients were prescribed probiotics, respectively. Of the patients receiving probiotic prescriptions in the AMPC and AMPC/CVA groups, 632 (95.9%) and 286 (97.6%) patients received antibiotic-resistant probiotic prescriptions, respectively. When classified by the prescribing clinical department and patient age, the proportions of probiotic prescriptions in Internal Medicine and Pediatrics departments were lower than those in the Otorhinolaryngology department regardless of age. These results indicate the probability of insufficient probiotic prescriptions for pediatric patients with otitis media. Solving this issue may lead to the provision of safer antimicrobial therapy.

Investigation of the Real-World Situation and Risk Factors Associated with Olanzapine Prescribed to Diabetes Patients by Using a Japanese Claims Database.

Olanzapine is effective for schizophrenia management; however, it is contraindicated in diabetes patients. In addition, olanzapine is useful for treating nausea and vomiting, such as in the case of chemotherapy-induced nausea and vomiting (CINV). Therefore, we hypothesized that the contraindicated prescription of olanzapine likely occurs among cancer patients with diabetes, especially by non-psychiatric physicians. Hence, we conducted a nationwide survey to elucidate the situation of such contraindicated prescriptions and the associated risk factors. We extracted the data of patients who were newly prescribed olanzapine between April 2015 and March 2017 from the health insurance claims database developed by JMDC, Inc., Tokyo. The patients who were prescribed contraindicated olanzapine were defined as those who were prescribed olanzapine after a diagnosis of diabetes and diabetes drug prescription. In all, the data of 7181 patients were analyzed. We evaluated the proportion of diabetes patients who were prescribed contraindicated olanzapine from among those who were prescribed olanzapine. Furthermore, we investigated the background of patients who were prescribed olanzapine for information such as olanzapine prescribers and history of cancer chemotherapy. In all, 100 diabetes patients (1.39%) were prescribed olanzapine. In these patients, the frequency of olanzapine prescription was higher by non-psychiatry/neurology physicians than by psychiatry/neurology physicians (3.25 and 0.85%, respectively). Additionally, all olanzapine prescriptions in cancer chemotherapy-treated diabetes patients were issued by non-psychiatry/neurology physicians. Thus, our study revealed there were diabetes patients who were prescribed olanzapine. Additionally, olanzapine for CINV management was more likely to be a contraindicated prescription.

Implementation Status of Liver Function Tests for Monitoring Benzbromarone-Induced Hepatotoxicity: An Epidemiological Survey Using the Japanese Claims Database.

A major adverse effect of benzbromarone is hepatotoxicity. Therefore, periodic liver function tests are required at least for the first 6 months of benzbromarone administration. However, it is not clear whether the relevant blood tests are implemented appropriately. Here, we performed a cross-sectional survey of the implementation status of liver function tests in patients who were newly prescribed benzbromarone, using the Japanese large claims database. Male patients who were newly prescribed benzbromarone from January 2010 to December 2016 were included. We targeted patients who continued benzbromarone during the observation period (up to 180 d from the start of administration). The primary endpoint was the proportion of patients in whom periodic liver function tests were implemented. A periodic liver function test was defined as one or more liver function tests performed during both 1-90 and 91-180 d of initial benzbromarone administration. We labeled the tests as a "periodic test" or "non-periodic test" based on whether periodic liver function tests were performed or not, respectively. Furthermore, factors influencing non-periodic test were analyzed. Periodic testing was implemented only in 28.7% of patients. Additionally, factors such as number of hospital beds ≤19 (compared to 100-199 beds) and duration of the first prescription of benzbromarone were associated with non-periodic testing. Our study revealed that periodic liver function tests are not performed sufficiently in Japan. Thus, clinicians prescribing benzbromarone should be educated about the test. Our blood-test-based approach should be applied to other drugs and countries in future research.

Determination of the concentration of gilteritinib in human plasma using HPLC.

Gilteritinib, an oral inhibitor of FMS-like tyrosine kinase 3 (FLT3), is a standard treatment for FLT3-mutated acute myeloid leukemia. We developed a simple HPLC-UV-based method for determining the concentration of gilteritinib in human plasma. The analysis requires the extraction of a 200-µL plasma sample and the precipitation of proteins by solid-phase extraction. Gilteritinib was isocratically separated within 10 min using a mobile phase of acetonitrile:0.5% monopotassium phosphate (KH2 PO4 , pH 3.5, 28:72, v/v) on a Capcell Pack C18 MG II (250 × 4.6 mm) column at a flow rate of 1.0 mL/min and monitored at 250 nm. The calibration curve was found to be linear within a plasma concentration range of 25-2500 ng/mL, with the coefficient of determination (r2 ) being 0.9997. The coefficients of intra-day and inter-day validation were 2.3-3.7 and 1.3-5.2%, respectively. The accuracy and recovery of the assay were -9.6 to 0.1 and >81.8%, respectively. This HPLC-UV method for determining the plasma concentration of gilteritinib is simple and can be effectively applied to routine drug monitoring.

Survey of the Time-Onset Profiles of Nedaplatin-Induced Adverse Events in Head and Neck Cancer Therapy.

OBJECTIVE: Cisplatin(CDDP)is a key drug for head and neck cancer therapy, but frequently induces severe adverse events including renal dysfunction. Nedaplatin(CDGP)was developed and is used in Japan; it has certain benefits over CDDP. Unlike CDDP, CDGP treatment does not require hydration. However, CDGP is not used globally and thus safety information is lacking. Therefore, we surveyed safety profiles for CDGP-based chemotherapy. METHODS: A survey was conducted at Showa University Hospital. Thirty-eight patients treated for head and neck cancer combined with radiotherapy(RTx)and tegafur- gimeracil-oteracil(S-1)between April 2012 and March 2015 were included. Laboratory-based adverse events(WBC, Hb, platelet[Plt], SCr, Alb)and oral mucositis were assessed according to CTCAE v5.0. Time-onset profiles for adverse events were evaluated after starting chemoradiotherapy. RESULTS: In 38 patients, Plt nadir was observed following 40(30-70)Gy and sustained for 14(7-35)days. WBC patterns followed similar profiles, but for Hb, nadir was observed following 60(40- 70)Gy and was less frequently sustained throughout the RTx. Alb and SCr levels were not correlated with therapy. Oral mucositis was observed following 50(10-70)Gy. CONCLUSION: In conclusion, at approximately 40 Gy, we observed decreases in WBC and Plt, with an increase in oral mucositis. Based on these results, medical staffs must closely monitor patients, especially at doses within range of 40 Gy.

Nonsteroidal anti-inflammatory drugs use in patients with chronic kidney disease are often prescribed from different clinicians than those who diagnosed them.

PURPOSE: When prescribing nonsteroidal anti-inflammatory drugs (NSAIDs) for chronic kidney disease (CKD), patients' pathology and concomitant medications should be considered. In our pharmaceutical experience, NSAIDs are often prescribed by departments that are different from those that diagnosed CKD. That is, NSAIDs may be prescribed for patients without the advice of the clinicians who diagnosed them. In this study, we aimed to elucidate how frequently such cases occur. METHODS: We used the large health insurance claims database constructed by JMDC Inc., Tokyo. We evaluated the proportions of CKD diagnosis and NSAID prescription by different clinical departments and institutions. RESULTS: A total of 224 014 out-patients were included in the analysis; they were divided into CKD (n = 1501) and non-CKD groups (n = 222 513). The internal medicine departments diagnosed CKD most frequently (74.8% of the patients) and surgical departments rarely diagnosed CKD. However, the proportion of prescribed NSAIDs was high in other departments, especially surgical departments. In the CKD group, 50.4% of the patients received CKD diagnosis and NSAID prescription from different clinical departments; 72.8% of the patients received a diagnosis and prescription from different medical institutions. CONCLUSION: Our study revealed that NSAIDs are often prescribed to patients with CKD from different clinicians than those who diagnosed them.

Prescription of Colchicine with Other Dangerous Concomitant Medications: A Nation-Wide Survey Using the Japanese Claims Database.

The anti-inflammatory agent colchicine may cause toxic effects such as rhabdomyolysis, pancytopenia, and acute respiratory distress syndrome in cases of overdose and when patients have renal or liver impairment. As colchicine is a substrate for CYP3A4 and P-glycoprotein (P-gp), drug-drug interactions are important factors that cause fatal colchicine-related side effects. Thus, we conducted a nation-wide survey to determine the status of inappropriate colchicine prescriptions in Japan. Patients prescribed the regular use of colchicine from April 2014 to March 2017 were identified using the Japanese large health insurance claims database. As the primary endpoint, we evaluated the concomitant prescription proportions of strong CYP3A4 and/or P-gp inhibitors classified as "contraindications for co-administration" with colchicine in patients with renal or liver impairment. We defined these cases as "inappropriate colchicine prescriptions." Additionally, factors affecting inappropriate colchicine prescriptions were analyzed. Among the 3302 enrolled patients, 43 (1.30%) were inappropriately prescribed colchicine. Of these 43 patients, 11 had baseline renal and/or liver impairment. By multiple regression analysis, the primary diseases "gout" and "Behçet's disease" were extracted as independent factors for inappropriate colchicine prescriptions with odds ratios of 0.40 (95% confidence interval: 0.19-0.84) and 4.93 (95% confidence interval: 2.12-11.5), respectively. We found that approximately 1% of patients had important colchicine interactions. Particularly, Behçet's disease was a risk factor for inappropriate prescriptions, with approximately 25% of patients showing renal and/or liver impairment (classified as "contraindications for co-administration"). These findings may be useful for medical professionals who prescribe colchicine therapy.

Potential thiamine deficiency in elderly patients with gastrointestinal cancer undergoing chemotherapy
.

Gastrointestinal cancer and its treatment using fluorouracil-based anticancer agents are risk factors for thiamine deficiency (TD). Therefore, we aimed to determine the prevalence of TD among elderly patients with gastrointestinal cancer undergoing chemotherapy. We retrospectively reviewed the medical records of 12 elderly patients with gastrointestinal cancers who underwent chemotherapy. Median serum thiamine level was 22.5 ng/mL (range, 17 - 42 ng/mL). Four patients (33.3%) exhibited TD (< 20 ng/mL). We found that the prevalence of TD among elderly patients with gastrointestinal cancer undergoing chemotherapy was high. For these patients, careful monitoring of thiamine levels is warranted because TD may not produce overt clinical symptoms.

Comparison of interactions between warfarin and cephalosporins with and without the N-methyl-thio-tetrazole side chain.

Cephalosporins with an N-methyl-thio-tetrazole (NMTT) side chain interact with warfarin by reducing the production of blood clotting factors. However, cephalosporins without the NMTT side chain also enhance the effects of warfarin. Thus, we aimed to compare the effects of warfarin modified by cephalosporins with and without the NMTT side chain, using a Japanese health insurance claims database. The inclusion criteria were patients who (1) intravenously received second- or third-generation cephalosporins between April 2010 and March 2017 and (2) received warfarin during cephalosporin therapy. Patients were administered either cephalosporins with the NMTT side chain (NMTT group) or those without NMTT (non-NMTT group). After matching patient data by propensity score, the following outcomes were compared between the two groups: (1) proportion of patients administered vitamin K, (2) proportion of bleeding events, and (3) changes in the daily dose of warfarin. Among 203 patients, 100 patients (50 per group) were matched by the propensity score. The proportion of patients administered vitamin K was 6.0% in both groups. These patients intravenously received a single dose of menatetrenone; no bleeding was observed. The proportion of patients subjected to a reduction in the daily dose of warfarin was 6.5% and 4.3% in the NMTT and non-NMTT groups, respectively. As our study had a small sample size, we could not determine whether the risk of over anticoagulation of warfarin is affected by cephalosporins with or without NMTT side chain. However, we showed the bleeding risk was sufficiently low regardless of the presence/absence of the NMTT side chain.