ABSTRACT
Pediatric ALK-positive anaplastic large cell lymphoma is a rare subtype of non-Hodgkin lymphoma, and approximately 30% of patients relapse following treatment with conventional chemotherapy. Alectinib monotherapy has demonstrated excellent activity in relapsed and refractory ALCL, but its role as a maintenance therapy after hematopoietic cell transplantation is unclear. We experienced a relapse case of pediatric ALK-positive ALCL with central nervous system involvement treated with alectinib maintenance therapy following cord blood transplantation. The patient has maintained complete remission for more than 3 years after transplantation. There were no remarkable adverse effects that led to discontinuation of alectinib.
Subject(s)
Carbazoles , Cord Blood Stem Cell Transplantation , Lymphoma, Large-Cell, Anaplastic , Piperidines , Humans , Piperidines/therapeutic use , Carbazoles/therapeutic use , Carbazoles/administration & dosage , Lymphoma, Large-Cell, Anaplastic/therapy , Lymphoma, Large-Cell, Anaplastic/drug therapy , Central Nervous System Neoplasms/therapy , Central Nervous System Neoplasms/drug therapy , Male , Maintenance Chemotherapy , Child , Female , Recurrence , AllograftsABSTRACT
OBJECTIVE: This study primarily focused on the diagnostic interval (DI), defined as the duration from the onset of leukemic symptoms to diagnosis. We investigated whether a prolonged DI is associated with the outcomes of pediatric leukemia. METHODS: We retrospectively collected data of children with newly diagnosed pediatric leukemia at Okayama University Hospital from January 2007 to December 2022. Survival analyses were conducted using Kaplan-Meier methods, and an unadjusted analysis to compare differences in survival was performed using the log-rank test. RESULTS: In total, 103 children with leukemia were included in the analysis. The median DI was 20 days (interquartile range, 9.5-33.5 days). A prolonged DI (≥30 days) demonstrated no association with either 5-year event-free survival (70.1% for <30 days and 68.3% for ≥30 days, p = .99, log-rank test) or overall survival (84.7% for <30 days and 89.4% for ≥30 days, p = .85, log-rank test). CONCLUSIONS: A prolonged DI was not associated with the survival of children with leukemia. If a precise classification of leukemia biology is provided for pediatric patients, a prolonged DI may have little impact on the prognosis of these patients.
Subject(s)
Precursor Cell Lymphoblastic Leukemia-Lymphoma , Child , Humans , Retrospective Studies , Prognosis , Survival Analysis , Progression-Free SurvivalABSTRACT
Cytomegalovirus (CMV) infection is a major complication of hematopoietic stem cell transplantation (HSCT). Previous studies in adults demonstrated that letermovir prophylaxis for 100 d after HSCT reduces the occurrence of CMV infection; however, studies in children are limited. In this study, we aimed to examine the incidence of CMV infection in children who underwent allogeneic HSCT with prophylactic letermovir therapy. A single-center retrospective study was conducted among patients aged ≤17 who underwent allogeneic HSCT. We compared the cumulative incidence of CMV infection, mainly monitored by pp65-antigenemia, after HSCT between patients with and without letermovir prophylaxis (10-12 or 5-6 mg/kg/d when co-administered with cyclosporine) using Gray's test. We analyzed 79 patients with a median follow-up period of 126 d. The median age of these patients was 8.3 years (Interquartile range, 3.7-12.4). Prophylactic letermovir was used in 25 patients. Twenty-five patients developed CMV infection, and the cumulative incidence was 38.9% (95% confidence intervals, 25.0-52.5). The cumulative incidence of CMV infection was not significantly different between the letermovir and no-letermovir groups (33.1 vs. 36.6%, p = 0.228). Meanwhile, the cumulative incidence of CMV infection up to 100 d following HSCT was significantly lower in the letermovir group than in the no-letermovir group (8.0 vs. 32.8%, p = 0.026). Most patients experienced no noticeable adverse effects associated with letermovir; however, one patient discontinued letermovir because of nausea and anorexia. In conclusion, the results of this study suggest that letermovir prophylaxis against CMV infection may be effective in children without severe adverse effects.
Subject(s)
Acetates , Antiviral Agents , Cytomegalovirus Infections , Hematopoietic Stem Cell Transplantation , Quinazolines , Humans , Cytomegalovirus Infections/prevention & control , Cytomegalovirus Infections/epidemiology , Cytomegalovirus Infections/etiology , Hematopoietic Stem Cell Transplantation/adverse effects , Retrospective Studies , Child , Antiviral Agents/therapeutic use , Antiviral Agents/administration & dosage , Male , Female , Child, Preschool , Quinazolines/therapeutic use , Quinazolines/administration & dosage , Japan/epidemiology , Acetates/administration & dosage , Acetates/therapeutic use , Acetates/adverse effects , Adolescent , Incidence , Transplantation, Homologous/adverse effectsABSTRACT
Asparaginase is an essential drug for acute lymphoblastic leukaemia (ALL) treatment, but has several side effects, and its discontinuation often compromises patient outcomes. In the prospective Japan Association of Childhood Leukaemia Study ALL-02 protocol, two major changes were made: (1) additional chemotherapies to compensate for the reduction of treatment intensity when asparaginase was discontinued and (2) more intensive concomitant corticosteroid administration, relative to our previous ALL-97 protocol. In ALL-02 study, 1192 patients were included and L-asparaginase was discontinued for 88 (7.4%). Discontinuation due to allergy was markedly decreased relative to the ALL-97 protocol (2.3% vs 15.4%). Event-free survival (EFS) among patients with T-ALL was compromised when L-asparaginase was discontinued, as well as among patients with high-risk B-cell ALL, especially when discontinued before maintenance therapy. Moreover, multivariate analysis identified discontinuation of L-asparaginase as an independent poor prognostic factor for EFS. In the current study, additional chemotherapies failed to fully compensate for L-asparaginase discontinuation, illustrating the difficulty of replacing asparaginase with other classes of drugs, although this study was not designed to evaluate the effect of these modifications. Concomitant intensive corticosteroid treatment may help to reduce allergy to asparaginase. These results will assist in further optimization of asparaginase use.
Subject(s)
Antineoplastic Agents , Hypersensitivity , Precursor Cell Lymphoblastic Leukemia-Lymphoma , Child , Humans , Infant , Asparaginase/adverse effects , Japan/epidemiology , Prospective Studies , Antineoplastic Agents/adverse effectsABSTRACT
A three-year-old boy with Philadelphia chromosome-positive B-cell precursor acute lymphoblastic leukemia (Ph+ALL) presented with an osteolytic lesion in his right upper arm. Tyrosine kinase inhibitors (TKIs) such as imatinib and dasatinib are an essential component throughout the course of treatment for Ph+ALL. However, TKIs are reported to affect the bone metabolism. In the treatment course of the current patient, the osteolytic lesion quickly improved despite the continuous use of TKIs, even during the concomitant use of corticosteroids. This suggests that TKIs can be safely given with concomitant corticosteroids to children with Ph+ALL, even when osteolytic lesions are present.
Subject(s)
Lymphoma, Non-Hodgkin , Osteolysis , Precursor Cell Lymphoblastic Leukemia-Lymphoma , Male , Child , Humans , Child, Preschool , Osteolysis/drug therapy , Osteolysis/etiology , Philadelphia Chromosome , Precursor Cell Lymphoblastic Leukemia-Lymphoma/drug therapyABSTRACT
BACKGROUND: Varicella-zoster virus (VZV) reactivation is a serious complication of hematopoietic stem cell transplantation (HSCT). Although low-dose acyclovir can prevent VZV reactivation after HSCT in adults, the efficacy of a dose of acyclovir lower than the recommended dose, such as 60-80Ā mg/kg/day in children, is unclear. In this study, we aimed to evaluate the incidence of VZV reactivation after HSCT during and after low-dose acyclovir administration for preventing VZV reactivation in children. METHODS: This single-center retrospective study included children aged ≤15Ā years who received oral acyclovir (at 15Ā mg/kg/day) to prevent VZV reactivation after HSCT. We examined the cumulative incidence of VZV reactivation after HSCT, during and after prophylactic acyclovir administration. RESULTS: Fifty-three eligible patients were included in this study, of whom 37 underwent allogeneic HSCT. The median duration of prophylactic acyclovir therapy was 264Ā days (range: 69-1140Ā days). VZV reactivation occurred in 13 patients (24.5%, 95% confidence interval [CI]: 14.9-37.6). The cumulative incidence of VZV reactivation 1 and 2Ā years after HSCT was 6.26% (95% CI: 1.60-15.5) and 20.9% (95% CI: 10.3-34.0), respectively. While only one patient developed VZV reactivation during the administration of prophylactic acyclovir, the cumulative incidence of VZV reactivation increased to 24.2% (95% CI: 12.5-38.0) 1Ā year after the cessation of acyclovir. CONCLUSION: Low-dose acyclovir (15Ā mg/kg/day) could be effective for preventing VZV reactivation after HSCT in children because VZV reactivation seldom occurs during the administration of 15Ā mg/kg/day acyclovir.
Subject(s)
Hematopoietic Stem Cell Transplantation , Herpes Zoster , Adult , Child , Humans , Acyclovir/pharmacology , Acyclovir/therapeutic use , Herpesvirus 3, Human/physiology , Retrospective Studies , Herpes Zoster/etiology , Herpes Zoster/prevention & control , Herpes Zoster/drug therapy , Transplantation, Homologous/adverse effects , Virus Activation , Antiviral Agents/therapeutic use , Hematopoietic Stem Cell Transplantation/adverse effectsABSTRACT
INTRODUCTION: Acute bacterial infectious diseases are major causes for outpatient visits for young children. Pivalate-conjugated antibiotics (PCAs) are frequently prescribed for these situations in Japan, while several literatures have shown a potential risk of hypoglycemia associated with PCAs. This study aimed to evaluate the incidence of PCA-induced hypoglycemia in children, compared with other oral beta-lactam antibiotics. METHODS: This retrospective cohort study using a Japanese medical and pharmacy claims database was performed on children aged 1 month to 5 years old with at least once prescription of PCAs or other oral beta-lactam antibiotics from January 2011 to December 2013. Hypoglycemia was defined based on diagnostic codes or the prescription of 10% or 20% glucose injection. We examined the prevalence of hypoglycemic events and performed multivariate analysis to investigate the risk of hypoglycemia with PCAs compared with the control oral beta-lactam antibiotics. RESULTS: We identified 179,594 eligible patients in this population. In the PCA and control groups, there were 454,153 and 417,287 prescriptions and 3356 (0.74%, 95% confidence intervals [CI] 0.71-0.76) and 2605 (0.62%, 95% CI 0.60-0.65) hypoglycemic events, respectively. Multivariate analysis revealed that PCAs were associated with hypoglycemia (adjusted odds ratios [OR] 1.18, 95% CI 1.12-1.24), and even a shorter duration of PCAs prescribing (≤7 days) was significantly associated with hypoglycemia (adjusted OR 1.17, 95% CI 1.11-1.24). CONCLUSION: These results suggest that in young children PCA use, even for a short period, is a risk factor of hypoglycemia.
Subject(s)
Anti-Bacterial Agents , Hypoglycemia , Pentanoic Acids/chemistry , Anti-Bacterial Agents/adverse effects , Anti-Bacterial Agents/chemistry , Antimicrobial Stewardship , Cephalosporins , Child, Preschool , Comorbidity , Databases, Factual , Female , Humans , Hypoglycemia/chemically induced , Hypoglycemia/epidemiology , Infant , Japan , Male , Retrospective StudiesABSTRACT
OBJECTIVES: Appropriate antibiotic prescriptions for outpatients with acute respiratory tract infections (ARTIs) are urgently needed in Japan. However, the empirical proof of this need is under-documented. Therefore, we aimed to determine antibiotic prescription rates, and the proportions of antibiotic classes prescribed for Japanese patients with ARTIs. METHODS: We analysed health insurance claims data over 2013-2015 among Japanese patients aged <75 years and determined the following indicators: 1) visit rates for patients with ARTIs and antibiotic prescription rates per 1000 person-years, and 2) proportion of visits by antibiotic-prescribed patients with ARTIs. We defined broad-spectrum antibiotics using the WHO Anatomical Therapeutic Chemical classification 4 level codes. RESULTS: Among 8.65 million visits due to ARTIs at 6859 hospitals and 62,024 physicians' offices, the visit rate and antibiotic prescription rate per 1000 person-years were 990.6 (99% confidence interval [CI], 989.4-991.7) and 532.4 (99% CI, 531.6-533.3), respectively. The visit rates for patients aged 0-17, 18-59, and 60-74 years were 2410.0 (99% CI, 2407.2-2412.9), 683.6 (99% CI, 682.7-684.6), and 682.1 (99% CI, 678.2-686.0), and antibiotic prescription rates were 1093.3 (99% CI, 1091.4-1095.2), 434.1 (99% CI, 433.4-434.9), and 353.4 (99% CI, 350.7-356.1), respectively. The overall proportion of antibiotic prescriptions for ARTI visits was 52.7% and 91.3% of the antibiotics prescribed were broad-spectrum. CONCLUSIONS: Both the visit rates and antibiotic prescription rates for ARTIs were high in this Japanese cohort. The proportion of antibiotic prescriptions exceeded that recommended in the clinical guidelines. Thus, there might be a scope for reducing the current antibiotic prescription rate in Japan.
Subject(s)
Ambulatory Care/statistics & numerical data , Anti-Bacterial Agents/therapeutic use , Drug Prescriptions/statistics & numerical data , Inappropriate Prescribing/statistics & numerical data , Respiratory Tract Infections/drug therapy , Acute Disease/epidemiology , Acute Disease/therapy , Administrative Claims, Healthcare/statistics & numerical data , Adolescent , Adult , Aged , Ambulatory Care/standards , Child , Child, Preschool , Drug Prescriptions/standards , Female , Humans , Inappropriate Prescribing/prevention & control , Infant , Japan/epidemiology , Male , Middle Aged , Practice Guidelines as Topic , Respiratory Tract Infections/epidemiology , Respiratory Tract Infections/microbiology , Retrospective Studies , Young AdultABSTRACT
Polymorphisms in methotrexate transporter pathways have been associated with methotrexate toxicities and clearance. Recent genome-wide association studies have revealed that the SLCO1B1 T521C variant is associated with methotrexate elimination. We present a case of a pediatric patient with acute lymphoblastic leukemia who suffered from persistently high plasma methotrexate concentrations and acute kidney injuries after the admin-istration of a medium dose of methotrexate. Subsequent genetic analysis showed that he was a carrier of dys-functional genetic variants associated with methotrexate clearance. This case highlights that polymorphisms of methotrexate transporter pathways can adversely affect methotrexate elimination in a clinically significant manner.
Subject(s)
Antimetabolites, Antineoplastic/pharmacokinetics , Methotrexate/pharmacokinetics , Precursor Cell Lymphoblastic Leukemia-Lymphoma/drug therapy , Antimetabolites, Antineoplastic/administration & dosage , Antimetabolites, Antineoplastic/blood , Child , Humans , Liver-Specific Organic Anion Transporter 1 , Male , Methotrexate/administration & dosage , Methotrexate/blood , Methylenetetrahydrofolate Reductase (NADPH2) , Polymorphism, Single Nucleotide/genetics , Precursor Cell Lymphoblastic Leukemia-Lymphoma/geneticsABSTRACT
BACKGROUND: In this age of antimicrobial resistance, unnecessary use of antibiotics to treat non-bacterial acute respiratory tract infections (ARTIs) and inappropriate use of antibiotics in treating bacterial ARTIs are public health concerns. PURPOSE: Our aim is to identify the pattern of oral antibiotic prescriptions for outpatients with ARTIs in Japan. METHODS: We analysed health insurance claims data of patients (aged ≤74 years) from 2013 to 2015, to determine the pattern of antibiotic prescriptions for outpatient ARTIs and calculated the proportion of each antibiotic. RESULTS: Data on 4.6 million antibiotic prescriptions among 1559394 outpatients with ARTIs were analysed. The most commonly prescribed classes of antibiotics included cephalosporins (41.9%), macrolides (32.8%) and fluoroquinolones (14.7%). The proportion of first-, second- and third-generation cephalosporins was 1.0%, 1.7% and 97.3%, respectively. Fluoroquinolones accounted for a quarter of the prescriptions for ARTIs in patients aged >20 years. In contrast, penicillins accounted for just 8.0% of the total number of antibiotic prescriptions for ARTIs. CONCLUSIONS: According to clinical guidelines, penicillins are first-line antibiotics against ARTIs. However, third-generation cephalosporins, macrolides and fluoroquinolones are more frequently prescribed in Japan. Although we could not assess the extent to which appropriate antibiotics are selected, our results support the necessity of improving antibiotic choices in the treatment of ARTIs.
Subject(s)
Anti-Bacterial Agents/therapeutic use , Fluoroquinolones/therapeutic use , Inappropriate Prescribing , Practice Patterns, Physicians'/statistics & numerical data , Respiratory Tract Infections/drug therapy , Respiratory Tract Infections/epidemiology , Adult , Aged , Female , Humans , Japan/epidemiology , Male , Middle Aged , Outpatients , Retrospective Studies , Young AdultABSTRACT
The application and clinical impact of rapid antigen detection test (RADT) in the treatment of acute pharyngitis is unknown in Japan. We aimed to examine the proportions of RADT usage to identify Group A Ć-hemolytic Streptococcus (GAS) in outpatients with acute pharyngitis and evaluate the association between RADT and antibiotic treatment. We analyzed health insurance claims data from 2013 to 2015. Logistic regression models were used to analyze associated factors with RADT, overall antibiotic prescription, or penicillin use. We analyzed 1.27 million outpatient visits with acute pharyngitis, in which antibiotics were prescribed in 59.3% of visits. Of the total visits, 5.6% of patients received RADT, and 10.8% of the antibiotics were penicillin. Penicillin selection rates were higher in cases with RADT (25.4%) than those without RADT (9.7%). Compared to large-scale facilities, antibiotic prescription rates were higher in physicians' offices. For factor analysis, age (3-15 years), diagnosis code (streptococcal pharyngitis), size of the medical facility (large-scale hospitals), and physician's specialty (pediatrics) were associated with RADT use. Penicillin selection rate increased with RADT implementation (25.4% vs. 9.7%: adjusted odds ratio 1.55; 95% CI, 1.50-1.60). At 63% of the facilities, the RADT implementation rate was <5% of acute pharyngitis visits prescribed antibiotics. In conclusion, the proportion of RADT usage for outpatients with acute pharyngitis was low in Japan. With appropriate indication and evaluation, we expect that more utilization of RADT can help promote antimicrobial stewardship for outpatients with acute pharyngitis by prompting penicillin therapy. Further investigation with detailed clinical data are warranted.
Subject(s)
Anti-Bacterial Agents/therapeutic use , Antigens, Bacterial/isolation & purification , Immunologic Tests/statistics & numerical data , Pharyngitis/drug therapy , Streptococcal Infections/drug therapy , Acute Disease/therapy , Adolescent , Adult , Aged , Anti-Bacterial Agents/pharmacology , Antimicrobial Stewardship/standards , Antimicrobial Stewardship/statistics & numerical data , Child , Child, Preschool , Humans , Immunologic Tests/instrumentation , Infant , Infant, Newborn , Japan , Middle Aged , Penicillins/pharmacology , Penicillins/therapeutic use , Pharyngitis/immunology , Pharyngitis/microbiology , Practice Guidelines as Topic , Reagent Kits, Diagnostic/statistics & numerical data , Retrospective Studies , Streptococcal Infections/immunology , Streptococcal Infections/microbiology , Streptococcus pyogenes/immunology , Streptococcus pyogenes/isolation & purification , Young AdultSubject(s)
Leukemia, Myeloid, Acute , Child , Humans , Leukemia, Myeloid, Acute/therapy , Aniline Compounds , Pyrazines , fms-Like Tyrosine Kinase 3 , MutationABSTRACT
Dementia is a major public health concern in ageing societies. Although the population of Japan is among the most aged worldwide, long-term trends in the place of death (PoD) among patients with dementia is unknown. In this Japanese nationwide observational study, we analysed trends in PoD using the data of patients with dementia who were aged ≥65 years and died during 1999-2016. Trends in the crude death rates and PoD frequencies were analysed using the Joinpoint regression model. Changes in these trends were assessed using the Joinpoint regression analysis in which significant change points, the annual percentage change (APC) and average APCs (AAPC) in hospitals, homes, or nursing homes were estimated. During 1999-2016, the number of deaths among patients with dementia increased from 3,235 to 23,757 (total: 182,000). A trend analysis revealed increased mortality rates, with an AAPC of 8.2% among men and 9.3% among women. Most patients with dementia died in the hospital, although the prevalence of hospital deaths decreased (AAPC: -1.0%). Moreover, the prevalence of nursing home deaths increased (AAPC: 5.6%), whereas the prevalence of home deaths decreased (AAPC: -5.8%). These findings support a reconsideration of the end-of-life care provided to patients with dementia.
Subject(s)
Cause of Death/trends , Death , Dementia/mortality , Hospital Mortality/trends , Nursing Homes/trends , Adult , Age Factors , Aged , Aged, 80 and over , Dementia/epidemiology , Female , Humans , Japan/epidemiology , Male , Middle Aged , Prevalence , Regression Analysis , Sex Factors , Survival Rate/trendsABSTRACT
OBJECTIVES: Fall-related mortality among older adults is a major public health issue, especially for ageing societies. This study aimed to investigate current trends in fall-related mortality in Japan using nationwide population-based data covering 1997-2016. DESIGN: We analysed fall-related deaths among older persons aged ≥65 years using the data provided by the Japanese Ministry of Health, Labour and Welfare. RESULTS: The crude and age-standardised mortality rates were calculated per 100 000 persons by stratifying by age (65-74, 75-84 and ≥85 years) and sex. To identify trend changes, a joinpoint regression model was applied by estimating change points and annual percentage change (APC). The total number of fall-related deaths in Japan increased from 5872 in 1997 to 8030 in 2016, of which 78.8% involved persons aged ≥65 years. The younger population (65-74 years) showed continuous and faster-decreasing trends for both men and women. Average APC among men aged ≥75 years did not decrease. Among middle-aged and older women (75-84 and ≥85 years) decreasing trends were observed. Furthermore, the age-adjusted mortality rate of men was approximately twice that of women, and it showed a faster decrease for women. CONCLUSIONS: Although Japanese healthcare has shown improvement in preventing fall-related deaths over the last two decades, the crude mortality for those aged over 85 years remains high, indicating difficulty in reducing fall-related deaths in the super-aged population. Further investigations to uncover causal factors for falls in older populations are required.
Subject(s)
Accidental Falls , Mortality/trends , Accidental Falls/mortality , Accidental Falls/prevention & control , Accidental Falls/statistics & numerical data , Aged , Aged, 80 and over , Female , Geriatrics/methods , Geriatrics/statistics & numerical data , Health Policy , Health Services Needs and Demand , Humans , Japan/epidemiology , Male , Public HealthABSTRACT
Background The trends in medication reviews made by community pharmacies in Japan are currently unknown. Objective We aimed to comprehensively describe the national trends in medication reviews in Japan's community pharmacies in the backdrop of the country's ageing population. Setting Community pharmacies in Japan. Methods We analysed national health insurance claims data for 2010-2015. These data were provided by the Ministry of Health, Labour and Welfare as part of the Survey of Medical Care Activities in Public Health Insurance. Main outcome measures The national trends in community pharmacy visits involving medicine dispensing and medication reviews that involve consultations with a physician. Results Among the 365 million pharmacy visits for 2010-2015, we identified 373,429 medication reviews accompanied by consultations with a physician. The pharmacy visit rate per 1000 population increased from 427.2 in 2010 to 483.7 in 2015. Medication reviews also increased from 407 per million pharmacy visits in 2010 to 1445 in 2015. Among the 373,429 medication reviews during the study period, the prescription was changed through collaboration with a physician 338,982 times (90.4%). The proportion of medication review acceptance increased from 80.6% in 2010 to 94.8% in 2015. The prescription change rate was higher among older patients than among younger ones. Conclusions Medication reviews by community pharmacists involving consultations with a physician increased in Japan from 2010 to 2015, as did prescription changes following these reviews.
Subject(s)
Community Pharmacy Services/trends , Insurance Claim Review/trends , Medication Therapy Management/trends , Pharmacists/trends , Professional Role , Adolescent , Adult , Aged , Child , Child, Preschool , Female , Humans , Infant , Infant, Newborn , Japan/epidemiology , Male , Medication Reconciliation , Middle Aged , Retrospective Studies , Young AdultABSTRACT
OBJECTIVES: To describe and examine trends in polypharmacy according to age in Japan from 2010 to 2016. DESIGN: Retrospective observational study. SETTING: Outpatient settings. PARTICIPANTS: Japanese individuals aged 20 and older. MEASUREMENTS: We analyzed pharmacy claims data that the Japanese Ministry of Health, Labor, and Welfare provided in the Survey of Medical Care Activities in Public Health Insurance from 2010 to 2016. The use of 5 or more oral prescription medications per month was defined as polypharmacy and of 10 or more as excessive polypharmacy. Regression analysis was used to estimate trends in polypharmacy with annual percentage changes. Using number of medications (polypharmacy vs excessive polypharmacy), trends in polypharmacy and crude and age-adjusted rates of polypharmacy per 1,000 persons were calculated according to year and age group (20-34, 35-49, 50-64, 65-79, ≥ 80). RESULTS: We analyzed 240 million pharmacy claims data. The age-adjusted monthly prevalence rate of polypharmacy increased from 85.2 to 93.8 per 1,000 persons per month and of excessive polypharmacy from 13.6 to 14.0 per 1,000 persons per month from 2010 to 2016 in the entire study population. The highest rate of polypharmacy (per 1,000 persons) was observed in 2016 in those aged 80 and older (326.8), followed by those aged 65 to 79 (167.3). The polypharmacy rate increased by 6.3% (95% confidence interval (CI)=4.0-8.7) per year from 2010 to 2012, then decreased by 0.7% (95% CI=-1.3-0.0) per year from 2012 to 2016. The rate of excessive polypharmacy increased by 4.5% (95% CI=1.1-8.0) per year from 2010 to 2013 and then decreased by 3.7% (95% CI=-6.7 to -0.6) per year from 2013 to 2016. CONCLUSION: The overall trend of polypharmacy in Japan increased during the study period, although the increase ceased in 2013 and then declined from 2013 to 2016. Policy changes in Japan might be responsible for some of the changes. J Am Geriatr Soc 66:2267-2273, 2018.