Health impact and cost effectiveness of implementing gender-neutral HPV vaccination in Japan.

OBJECTIVE: To assess the public health impact and cost effectiveness of gender-neutral vaccination (GNV) versus female-only vaccination (FOV) with human papillomavirus (HPV) vaccination in Japan. METHODS: We modeled the public health impact and cost effectiveness of GNV versus FOV to prevent HPV-associated diseases in Japan over the next 100 years. We used one-way sensitivity analyses to examine the impact of varying key model input parameters and conducted scenario analyses to explore the effects of varying the vaccination coverage rate (VCR) of each cohort. RESULTS: In the base-case analysis, GNV averted additional cancer cases (17,228 female/6,033 male) and deaths (1,892 female/1,849 male) compared to FOV. When all HPV-associated diseases were considered, GNV had an incremental cost-effectiveness ratio of ¥4,732,320 (US$35,987)/quality-adjusted life year gained compared to FOV. The model was most sensitive to the discount rate and the disutility associated with HPV-related diseases. GNV had greater relative public health benefits when the female VCR was lower and was cost effective at a female VCR of 30%. CONCLUSIONS: Immediate implementation of GNV would reduce the disease burden and mortality associated with HPV in Japan, and would be cost effective compared to FOV if the female VCR remains low (30%).

Human papillomavirus (HPV) is a common sexually transmitted infection and, in Japan, the prevalence of HPV infection and the incidence of its associated diseases are high among both men and women. In the present manuscript we modeled the public health impact and cost effectiveness of gender-neutral vaccination versus female-only vaccination to prevent HPV-associated diseases in Japan over the next 100 years and found that immediate implementation of a gender-neutral vaccination strategy would reduce the burden and mortality associated with HPV in Japan.

Cost-effectiveness analysis of pediatric immunization program with 15-valent pneumococcal conjugate vaccine in Japan.

BACKGROUND: The 15-valent pneumococcal conjugate vaccine (PCV15 or V114) has recently been approved for pediatric vaccination against pneumococcal diseases (PDs) in Japan. The study aims to evaluate the cost-effectiveness of pediatric vaccination with V114 versus 13-valent PCV (PCV13) in Japan. METHODS: The study used a decision analytical Markov model to estimate the cost and effectiveness outcomes for a birth cohort in Japan over a 10-year time horizon. The model tracked the occurrences of acute PD events, including invasive PD (IPD), non-bacteremic pneumococcal pneumonia (NBPP) and pneumococcal acute otitis media (AOM) and the long-term impact of post-meningitis sequalae. Vaccine effectiveness was estimated based on literature and assumptions, and accounted for indirect effects and vaccine waning. The base case took the societal perspective, including both direct and indirect costs, while a healthcare payer perspective was modeled in a scenario analysis. Additional scenario analyses and sensitivity analyses were conducted. RESULTS: In the base case, V114 was associated with an incremental gain of 24 quality-adjusted life years and a reduction of ¥365,610,955 in total costs compared to PCV13. It was expected to reduce the number of pneumococcal AOM, NBPP, and IPD cases by 1,832, 1,333 and 25, respectively. All scenario analyses and most sensitivity analyses showed that V114 was a dominant strategy compared to PCV13. CONCLUSIONS: Pediatric vaccination with V114 is expected to lead to cost savings and more health benefits compared to PCV13 in Japan from both societal and healthcare payer perspectives. The findings are robust under plausible assumptions and inputs.

Health Care Resource Use Among Patients with Advanced Non-Small Cell Lung Cancer in Japan, 2017-2019.

Background: First-line immune checkpoint inhibitor (ICI) monotherapy for advanced non-small cell lung cancer (NSCLC) was introduced in Japan in February 2017. Limited information is available since that time regarding health care resource use for NSCLC in Japan, where the hospitalization burden is high. Objective: We evaluated health care resource use from first- through third-line systemic anticancer therapy for patients with advanced NSCLC included in a multicenter, retrospective chart review study. Methods: Eligible patients were aged 20 years or older with unresectable locally advanced/metastatic NSCLC with no known actionable genomic alteration who initiated first-line systemic anticancer therapy from July 1, 2017, to December 20, 2018, at 23 Japanese hospitals. We calculated the percentage of patients with a record of each resource used, the total number of each resource, and the resource use per 100 patient-weeks of follow-up from initiation of first-, second-, and third-line therapy, overall and by the 3 most common regimen categories, namely, ICI monotherapy, platinum-doublet chemotherapy (without concomitant ICI), and nonplatinum cytotoxic regimens (nonplatinum). Study follow-up ended September 30, 2019. Results: Among 1208 patients (median age = 70 years; 975 [81%] men), 463 patients (38%) received ICI monotherapy, 647 (54%) received platinum-doublet chemotherapy, and 98 (8%) received nonplatinum regimens as first-line therapy. During the study, 621 (51%) patients initiated second-line, and 281 (23%) initiated third-line therapy. The majority of patients experienced ≥1 hospitalization (76%-94%) and ≥1 outpatient visit (85%-90%) during each therapy line. The number of hospitalizations increased from 6.5 per 100 patient-weeks in first-line to 8.0 per 100 patient-weeks in third-line. During first-line therapy, the number of hospitalizations per 100 patient-weeks were 4.8, 8.4, and 6.5 for patients receiving ICI monotherapy, platinum-doublet chemotherapy, and nonplatinum regimens, respectively, and the percentages of hospitalizations categorized as attributable to NSCLC treatment administration (no surgery, procedure, treatment of metastasis, or palliative lung radiation) were 64%, 77%, and 73%, respectively. The number of outpatient visits increased from 43.0 per 100 patient-weeks in first-line to 51.4 per 100 patient-weeks in third-line therapy. During first-line therapy, outpatient visits per 100 patient-weeks were 41.0, 46.7, and 33.0 for patients receiving ICI monotherapy, platinum-doublet chemotherapy, and nonplatinum regimens, respectively, and the percentages of outpatient visits for infusion therapy were 48%, 34%, and 36%, respectively. Conclusions: The results of this study, although solely descriptive, showed differing patterns of health care resource use during first-line therapy among the 3 common systemic anticancer therapy regimens for advanced NSCLC in Japan and suggest that further research is needed to investigate these apparent differences by treatment regimen.

First-Line Pembrolizumab Monotherapy for Advanced NSCLC With Programmed Death-Ligand 1 Expression Greater Than or Equal to 50%: Real-World Study Including Older Patients in Japan.

Introduction: Pembrolizumab became available in Japan in February 2017 for first-line monotherapy of unresectable advanced and metastatic NSCLC with programmed death-ligand 1 (PD-L1) tumor proportion score (TPS) greater than or equal to 50%. This retrospective chart review study aimed to describe real-world clinical outcomes of first-line pembrolizumab monotherapy, including for patients 75 years or older, who are under-represented in clinical trials. Methods: We identified patients (≥20 y old) at 23 sites initiating first-line pembrolizumab monotherapy from July 1, 2017, to December 20, 2018, for stages IIIB, IIIC, and IV NSCLC with PD-L1 TPS greater than or equal to 50% and Eastern Cooperative Oncology Group performance status of 0 to 2 or unknown. Patients with actionable genomic alterations (EGFR, ALK, ROS1, BRAF) and clinical trial participants were excluded. Time-to-event outcomes were estimated using Kaplan-Meier, with data cutoff on September 30, 2019. Results: Of 441 eligible patients (78% men), 303 (69%) were younger than 75 years and 138 (31%) were 75 years or older; median age was 70 years. With median follow-up of 13.5 months, median overall survival (OS) was not reached (NR); 12- and 24-month OS rates were 72% and 58%, respectively. For ages younger than 75 and 75 years or older, median OS was NR and 23.5 months (95% confidence interval: 16.2-NR), respectively; 12-month OS rates were 74% and 67% and 24-month OS rates were 62% and 48%, respectively. Median real-world progression-free survival was similar in the two age groups (10.1 and 9.5 mo, respectively), as was median real-world time on treatment with pembrolizumab (5.7 and 5.6 mo). Conclusions: These findings complement clinical trial results, adding real-world evidence supporting benefits of first-line pembrolizumab monotherapy for advanced NSCLC with PD-L1 TPS greater than or equal to 50%, including for patients 75 years or older.

Real-World Treatments and Clinical Outcomes in Advanced NSCLC without Actionable Mutations after Introduction of Immunotherapy in Japan.

The aims of this study were to describe systemic treatment patterns and clinical outcomes for unresectable advanced/metastatic non-small-cell lung cancer (NSCLC) by first-line regimen type in real-world clinical settings in Japan after the introduction of first-line immune checkpoint inhibitor (ICI) monotherapy in 2017. Using retrospective chart review at 23 study sites, we identified patients ≥20 years old initiating first-line systemic therapy from 1 July 2017 to 20 December 2018, for unresectable stage IIIB/C or IV NSCLC; the data cutoff was 30 September 2019. Eligible patients had recorded programmed death-ligand 1 (PD-L1) tumor proportion score (TPS) and no known actionable EGFR/ALK/ROS1/BRAF genomic alteration. Kaplan-Meier method was used to determine time-to-event endpoints. Of 1208 patients, 647 patients (54%) received platinum doublet, 463 (38%) received ICI monotherapy, and 98 (8%) received nonplatinum cytotoxic regimen as first-line therapy. PD-L1 TPS was ≥50%, 1−49% and <1% for 44%, 30%, and 25% of patients, respectively. Most patients with PD-L1 TPS ≥50% received ICI monotherapy (453/529; 86%). Excluding 26 patients with ECOG performance status of 3−4 from outcome analyses, the median patient follow-up was 11.3 months. With first-line platinum doublet, ICI monotherapy, and nonplatinum cytotoxic regimens, median overall survival (OS) was 16.3 months (95% CI, 14.0−20.1 months), not reached, and 14.4 months (95% CI, 10.3−21.2 months), respectively; 24-month OS was 40%, 58%, and 31%, respectively. Differences in OS relative to historical cohort data reported in Japan are consistent with improvement over time in real-world clinical outcomes for advanced NSCLC.

Medical Costs Associated with Insomnia Treatment with Suvorexant Monotherapy in Japan: Results from a Retrospective Cohort Study Using a Large-Scale Claims Database.

BACKGROUND: The association of insomnia treatment with medical costs is not well characterized in Japan, despite the high economic burden of insomnia. OBJECTIVE: The aim of this study was to investigate the impact of suvorexant, the first dual orexin receptor antagonist, on direct medical costs in insomnia patients. PATIENTS AND METHODS: This retrospective cohort study, conducted using a large-scale claims database, included Japanese patients with diagnosed insomnia receiving suvorexant who were treatment naïve or treatment switchers (pre-treated with a different hypnotic and switched to suvorexant). Total medical costs were estimated for 1 year before and after suvorexant initiation; p-values were calculated for the difference in costs. RESULTS: Of the 1730 patients included, 1116 were treatment naïve and 614 were treatment switchers. Switching to suvorexant did not change the total treatment cost (US$4693-US$4692; p = 0.9964). Although treatment-naïve patients on average incurred US$3259 after suvorexant initiation, much of the additional cost was attributed to drugs other than hypnotics in the outpatient setting (US$332; p < 0.0001). While ~ 10% of the additional medical costs in the outpatient setting were attributable to hypnotics in both groups (treatment naïve: US$106, p < 0.0001; treatment switchers: US$115, p < 0.0001), no difference was observed in the inpatient setting. CONCLUSION: Suvorexant as an initial insomnia treatment was associated with higher total medical costs, given the additional burden of initiating treatment and monitoring costs associated with a new insomnia diagnosis. However, despite a switch from another hypnotic, suvorexant did not increase the incremental economic burden. The hypnotic cost remained proportionately low, demonstrating that suvorexant initiation did not raise the cost of insomnia treatment.

Web-based survey to evaluate the prevalence of chronic and subacute cough and patient characteristics in Japan.

BACKGROUND: Cough lasting 3-8 weeks and more than 8 weeks are defined as subacute/prolonged cough and chronic cough, respectively. Japanese chronic cough population has not been well studied. This study aimed to describe the prevalence and characteristics of chronic cough and subacute cough patients in Japan. This study also sought to compare between chronic cough patients who were not greatly satisfied with treatment effectiveness for resolving cough and other chronic cough patients. METHODS: Data from a cross-sectional online 2019 Japan National Health and Wellness Survey and a supplemental chronic cough survey were used to understand respondents' chronic cough status and their cough-specific characteristics and experience. The prevalence, patient characteristics and cough-specific characteristics were summarised descriptively. Patients who were not greatly satisfied with treatment effectiveness and other chronic cough patients were compared for their characteristics and cough severity. RESULTS: The point prevalence of chronic cough was 2.89% and 12-month period prevalence was 4.29%. Among all chronic cough patients analysed, the average age was 56 years old, 61.1% were males and 29.4% were current smokers. Patients were most frequently told by a physician that cough was related to allergic rhinitis, asthma and cough variant asthma. Only 44.2% of chronic cough patients had spoken with a physician about their cough, and half of chronic cough patients did not use any medications. Patients who were not greatly satisfied with treatment effectiveness had significantly greater cough severity during past 2 weeks compared with other chronic cough patients (Visual Analogue Scale 45.34 vs 39.63). CONCLUSIONS: This study described the prevalence and patient characteristics information of chronic cough patients in Japan. Furthermore, the study highlighted an unmet need for better diagnosis and treatments for chronic cough patients, especially among patients who were not greatly satisfied with treatment effectiveness and reported significantly worse cough severity.

Disease burden and quality of life of patients with chronic cough in Japan: a population-based cross-sectional survey.

BACKGROUND: Cough lasting 3-8 and >8 weeks are defined as subacute/prolonged cough and chronic cough (CC), respectively. Studies have revealed that CC negatively impact patients' quality of life (QoL). In Japan, there is limited data on the impact of CC on health-related quality of life (HRQoL), work productivity and activity impairment (WPAI) and healthcare resource utilisation (HRU) using validated instruments. This study aimed to estimate the burden of CC and to compare the burden among patients with CC between subgroups. METHODS: Data from two cross-sectional online surveys conducted between September and November 2019 were combined for the analysis. Eligible patients with cough were propensity score matched to non-cough respondents. Comparisons of general HRQoL, WPAI, HRU and other symptoms experienced were conducted between matched non-cough respondents and patients with cough. Among patients with CC, subgroup comparisons were performed to understand general HRQoL, WPAI, HRU, cough-related QoL (Leicester Cough Questionnaire and Hull Airway Reflux Questionnaire) between patients with CC of different severities, patients with refractory CC and patients with non-refractory CC and patients with CC whose underlying diseases were unknown and others. RESULTS: Patients with CC (n=568) in Japan reported significantly poorer HRQoL, increased WPAI, more HRU and higher proportion of psychological and sleep problems, compared with matched non-cough respondents selected from 21 415 non-cough respondents. More patients with severe CC reported significantly poorer HRQoL, increased WPAI and worse cough-related QoL. Patients with refractory CC experienced significantly greater burden measured by cough-related QoL. No significant differences were observed between patients with CC whose underlying diseases were unknown and other patients with CC in terms of general HRQoL and cough-related QoL. CONCLUSIONS: This study showed that patients with CC in Japan experienced significant burden compared with non-cough respondents. Patients with more severe cough and refractory CC experienced worse cough-related QoL. These results highlighted the unmet need for better interventions and treatments to reduce the burden among patients with CC.

Public health impact and cost effectiveness of routine and catch-up vaccination of girls and women with a nine-valent HPV vaccine in Japan: a model-based study.

BACKGROUND: Combined with cancer screening programs, vaccination against human papillomavirus (HPV) can significantly reduce the high health and economic burden of HPV-related disease in Japan. The objective of this study was to assess the health impact and cost effectiveness of routine and catch-up vaccination of girls and women aged 11-26 years with a 4-valent (4vHPV) or 9-valent HPV (9vHPV) vaccine in Japan compared with no vaccination. METHODS: We used a mathematical model adapted to the population and healthcare settings in Japan. We compared no vaccination and routine vaccination of 12-16-year old girls with 1) 4vHPV vaccine, 2) 9vHPV vaccine, and 3) 9vHPV vaccine in addition to a temporary catch-up vaccination of 17-26 years old girls and women with 9vHPV. We estimated the expected number of disease cases and deaths, discounted (at 2% per year) future costs (in 2020 ¥) and discounted quality-adjusted life years (QALY), and incremental cost effectiveness ratios (ICER) of each strategy over a time horizon of 100 years. To test the robustness of the conclusions, we conducted scenario and sensitivity analyses. RESULTS: Over 100 years, compared with no vaccination, 9vHPV vaccination was projected to reduce the incidence of 9vHPV-related cervical cancer by 86% (from 15.24 new cases per 100,000 women in 2021 to 2.02 in 2121). A greater number of cervical cancer cases (484,248) and cancer-related deaths (50,102) were avoided through the described catch-up vaccination program. Routine HPV vaccination with 4vHPV or 9vHPV vaccine prevented 5,521,000 cases of anogenital warts among women and men. Around 23,520 and 21,400 diagnosed non-cervical cancers are prevented by catch-up vaccination among women and men, respectively. Compared with no vaccination, the ICER of 4vHPV vaccination was ¥975,364/QALY. Compared to 4vHPV, 9vHPV + Catch-up had an ICER of ¥1,534,493/QALY. CONCLUSIONS: A vaccination program with a 9-valent vaccine targeting 12 to 16 year-old girls together with a temporary catchup program will avert significant numbers of cases of HPV-related diseases among both men and women. Furthermore, such a program was the most cost effective among the vaccination strategies we considered, with an ICER well below a threshold of ¥5000,000/QALY.

Serotype distribution and antimicrobial susceptibility of Streptococcus pneumoniae associated with invasive pneumococcal disease among adults in Japan.

OBJECTIVES: This study evaluated the serotype distribution and antimicrobial susceptibility of Streptococcus pneumoniae isolates from adults (aged ≥20 years) with invasive pneumococcal disease (IPD) in Japan. METHODS: This prospective observational study was conducted in 49 participating Japanese hospitals. S. pneumoniae isolates were serotyped and tested for antimicrobial susceptibility at a central laboratory. Information regarding patient characteristics, underlying disease, IPD clinical syndromes, and treatment was collected through medical chart review. RESULTS: The final analysis included 177 patients enrolled from 45 hospitals between September 2016 and April 2018 (bacteraemic pneumonia, 110; bacteraemia without identified focus, 29; meningitis, 19). Most patients (70.1%) were aged ≥65 years and most had underlying disease (79.1%). The proportion of isolates from serotypes contained in the pneumococcal polysaccharide vaccine (PPV) 23 was 61.0%, while those in the pneumococcal conjugate vaccine (PCV) 7 and PCV13 were 2.8% and 28.2%, respectively. Non-vaccine serotypes accounted for 37.9% of all isolates and 50.8% of isolates from immunosuppressed patients. Serotype 12F was the most common vaccine serotype, followed by serotype 3. CONCLUSIONS: The continued disease burden of IPD in adults in Japan warrants improved vaccination rates and development of next-generation vaccines that include serotypes not currently covered. CLINICAL TRIAL REGISTRATION: Clinical trial summary registration number 160,822,918,146; JapicCTI-163352.

Retrospective analysis of medical costs and resource utilization for severe hypoglycemic events in patients with type 2 diabetes in Japan.

AIMS/INTRODUCTION: The present study aimed to describe hospital utilization and examine actual medical costs for severe hypoglycemic events in patients with type 2 diabetes mellitus in Japan. MATERIALS AND METHODS: Medical resource utilization associated with severe hypoglycemia was evaluated using a receipt database of acute-care hospitals in Japan. Patients with type 2 diabetes treated with antihyperglycemic agents were included. Severe hypoglycemic events were identified and divided into two groups: with or without hospitalization. Total and attributable medical costs per event were calculated based on the actual medical treatment after severe hypoglycemic events. Attributable costs were estimated from the receipt codes directly associated with the treatment of severe hypoglycemia. RESULTS: In the hospitalized patients, the median length of hospital stay was 11 days, and the median total and attributable medical costs were ¥402,081 and ¥302,341, respectively. The majority of the hospitalized patients underwent a radiographic examination and general blood tests. Apart from the hospitalization costs, the costs associated with diagnosis accounted for 29.6% of the total medical costs. In the outpatients, 60.6% visited hospitals only once for the severe hypoglycemic event, whereas 11.4% visited hospitals daily for a week after the severe hypoglycemic event. The mean number of hospital visits of the outpatient after a severe hypoglycemic event was 2.7 ± 2.6 days. The median total and attributable medical costs were ¥265,432 and ¥4,628, respectively. CONCLUSIONS: Significant medical resources are used for the treatment of severe hypoglycemic events of patients with type 2 diabetes in Japan.

Healthcare burden of recurrent Clostridioides difficile infection in Japan: A retrospective database study.

This retrospective database study aimed to assess the healthcare burden of hospitalization cost and duration associated with recurrent Clostridioides difficile infection (rCDI) by comparison with C. difficile infection (CDI) in Japan, using a health claims database of 270 acute care hospitals. Overall, 5423 hospitalized patients, with a record of one hospital-onset, healthcare facility-associated primary CDI episode within the 180-day period, from its onset between January 2012 and September 2016, were included. Of these, 353 had at least one rCDI and 5070 had no rCDI. Compared with those with no rCDI, the median total cost of hospitalization for patients with rCDI was JPY 1,184,371 (USD 11,691) higher (JPY 2,489,424 [interquartile range {IQR}: 1,597,424-4,008,751] compared with JPY 1,305,053 [624,033-2,549,569]). In addition, rCDI resulted in twice longer hospitalization duration in median compared with CDI (79 days [IQR: 53-117] compared with 40 days [20-74]). Based on a generalized linear regression model with a Gamma distribution and a logarithmic link function, the estimated mean of cost and duration of hospitalization for patients with rCDI were JPY 1,284,519 (95% confidence limit: -95,532-2,664,569) (USD 12,679) higher and 20.3 days (-9.5‒50.0) longer, compared with patients with no rCDI. The estimated mean difference in cost was higher in older patients and patients with diseases resulting in an immunosuppressive state. Higher costs and longer hospitalization for rCDI impose a great burden on healthcare system as well as patients, highlighting the importance of preventing recurrence of CDI.

A cost-effectiveness analysis of revaccination and catch-up strategies with the 23-valent pneumococcal polysaccharide vaccine (PPV23) in older adults in Japan.

OBJECTIVE: In Japan, the National Immunization Program (NIP) includes PPV23 as the primary vaccination for adults and catch-up cohorts. The Japanese Association for Infectious Diseases recommends revaccination for older adults who received primary vaccination ≥5 years earlier. The cost-effectiveness of adding revaccination and/or continuing catch-up vaccination in the NIP was evaluated from the public payer perspective in Japan. METHODS: The Markov model included five health states: no pneumococcal disease, invasive pneumococcal diseases (IPD), non-bacteremic pneumococcal pneumonia (NBPP), post-meningitis sequelae, and death. Cohorts of adults aged 65-95 were followed until age 100 or death: 2014 cohort (aged 65-95, vaccinated: 2014); 2019 cohort (aged 65: 2019); and 2019 catch-up cohort (aged 70-100: 2019, unvaccinated: 2014). Strategies included: (1) vaccinate 2014 and 2019 cohorts; (2) vaccinate 2014 and 2019 cohorts and revaccinate both; (3) strategy 1 and vaccinate 2019 catch-up cohort; (4) strategy 2 and vaccinate 2019 catch-up cohort; and (5) strategy 4 and revaccinate 2019 catch-up cohort. Parameters were retrieved from global and Japanese sources, costs and QALYs discounted at 2%, and incremental cost-effectiveness ratios (ICERs) estimated. RESULTS: Strategy 1 had the highest number of IPD and NBPP cases, and strategy 5 the lowest. Strategies 3-5 dominated strategy 1 and strategy 2 was cost-effective compared to strategy 1 (ICER: ¥1,622,153 per QALY gained). At a willingness-to-pay threshold of ¥5 million per QALY gained, strategy 2 was cost-effective and strategies 3-5 were cost-saving compared to strategy 1. CONCLUSIONS: Strategies including revaccination, catch-up, or both were cost-effective or cost-saving in comparison to no revaccination and no catch-up. Results can inform future vaccine policies and programs in Japan.

Incidence rate and patient characteristics of severe hypoglycemia in treated type 2 diabetes mellitus patients in Japan: Retrospective Diagnosis Procedure Combination database analysis.

AIMS/INTRODUCTION: To evaluate the incidence rate of and identify factors associated with severe hypoglycemic episodes in patients with treated type 2 diabetes mellitus. MATERIALS AND METHODS: Using Diagnosis Procedure Combination hospital-based medical database, we carried out a retrospective cohort study to assess the incidence rate of severe hypoglycemia in treated type 2 diabetes mellitus patients. We evaluated the associations between severe hypoglycemia and age, sex, complications, and current use of insulin or sulfonylurea (SU) in a nested case-control study. RESULTS: Of 166,806 eligible patients, 1,242 had episodes of severe hypoglycemia during the observational period. The incidence rate of the first hypoglycemic events was 3.70/1,000 patient years. Based on the nested case-control analysis, age was associated with hypoglycemic events with adjusted odds ratios (ORs) of 1.64 or 65-74-year-old patients and 3.79 for ≥75-year-old patients in comparison with 20-64-year-old patients. Comorbidities, such as cognitive impairment, cancer, macrovascular disease and diabetic complications (retinopathy, nephropathy and neuropathy), were associated with severe hypoglycemia, with adjusted ORs ranging from 1.25 to 3.80. Severe hypoglycemic events also increased in patients with current use of both SU and insulin, either SU or insulin, with adjusted ORs of 18.36, 6.31 or 14.07, respectively, compared with patients with other antihyperglycemic agents. In patients with an SU glimepiride, adjusted ORs increased dose-dependently from 3.65 (≤1 mg) to 13.34 (>2 mg). CONCLUSIONS: The incidence rate of severe hypoglycemia in this cohort was 3.70/1,000 patient years. Age, cognitive impairment, cancer, diabetic complications, current use of insulin + SU and SU dosage were identified as risk factors for severe hypoglycemia.

Cost-effectiveness of a pentavalent rotavirus vaccine in Japan.

OBJECTIVE: To evaluate the impact of universal vaccination with a pentavalent rotavirus vaccine (RV5) on the healthcare burden and costs associated with rotavirus gastroenteritis (RGE) in Japan. METHODS: The model included a hypothetical cohort of 1,091,156 children followed for their first 5 years of life. In the absence of universal vaccination, there were 19 deaths, 78,000 hospitalizations, and 678,000 outpatient visits due to RGE. The efficacy of RV5 is based on international clinical trial data, which was similar to the efficacy observed in clinical trials conducted in Japan. The primary outcome measure is the cost per quality-adjusted-life-year (QALY) gained. In the base case, the QALY loss per 1000 RGE episodes included 2.2 for children and 1.8 per parent. RESULTS: Universal vaccination is projected to reduce hospitalizations by 92%, outpatient visits by 74%, and work-loss days by 73%. For the base case analysis, the total vaccination cost was ¥26 billion. The estimated reduction in medical costs was ¥16 billion. Of 2500 QALYs gained with the vaccination program, approximately half are directly attributed to the child. In the base case analysis, the incremental cost-effectiveness ratio (ICER) for vaccination vs. no vaccination is ¥4 million and ¥2 million per quality-adjusted life year (QALY) gained from the healthcare payer and societal perspectives, respectively. The ICERs are ¥8 million and ¥4 million if parental disutilities are excluded. KEY LIMITATION: The QALY decrements for children and parents were evaluated using different instruments, and the QALY decrements do not vary based on episode severity. Given the interdependence between children and their parents, excluding parental disutilities may under-estimate the impact of RGE. CONCLUSION: Universal vaccination with RV5 in Japan is projected to have a substantial public health impact and may be cost-effective from both the payer and societal perspectives if parental disutilities are included in the cost-effectiveness ratios.

The Cost-Effectiveness Analysis of a Quadrivalent Human Papillomavirus Vaccine (6/11/16/18) for Females in Japan.

OBJECTIVE: We assessed the epidemiological and economic impact of a quadrivalent human papillomavirus (HPV) (6/11/16/18) vaccine for females in preventing cervical cancer, cervical intraepithelial neoplasia grades 2 and 3 (CIN 2/3), cervical intraepithelial neoplasia grade 1 (CIN 1), and genital warts in Japan by using a transmission dynamic model. METHODS: A published mathematical model of the transmission dynamics of HPV infection and disease was adapted for Japan. Model inputs were used from Japan or the Asia/Pacific region when available; otherwise, the default values in the original model were used. The transmission dynamic model was used to assess the epidemiological and economic impact of a quadrivalent HPV (6/11/16/18) vaccine for females in preventing cervical cancer, CIN 2/3, CIN 1, and genital warts in Japan.Maintaining current cervical cancer screening practices, we evaluated two strategies: routine vaccination of females by age 12 years (S1), and S1 combined with a temporary (5 years) female catch-up program for age 12 to 24 years (S2). The vaccine coverage rate was 80% for the routine and 50% for the catch-up vaccination programs. RESULTS: Compared with no vaccination, both vaccination strategies significantly reduced the incidence of HPV 6/11/16/18-related disease. The most effective strategy was S2. By using this strategy over 100 years in the Japanese population, the estimated cumulative percentage reduction in incident HPV 6/11/16/18-related genital warts-female, genital warts-male, cervical CIN 1, CIN 2/3, and cervical cancer cases was 90% (2,113,723 cases), 86% (2,082,637 cases), 72% (263,406 cases), 71% (1,328,366 cases), and 58% (323,145 cases), respectively. The cost-effectiveness ratios were JPY 1,244,000, and JPY 1,205,800 per quality-adjusted life-year gained for S1 and S2 compared with no vaccination, respectively, over a time horizon of 100 years. CONCLUSION: We conclude that a quadrivalent HPV vaccination program for females can reduce the incidence of cervical cancer, CIN, and genital warts in Japan at a cost-per-quality-adjusted life-year ratio within the range defined as cost-effective.

Quality assessment of umbilical cord blood units at the time of transplantation.

Total nucleated cell (TNC) count, CD34(+) cell count, colony-forming unit-granulocyte-macrophage (CFU-GM) content, and cell viability impact the outcome of umbilical cord blood (UCB) transplantation. Assessments of unit quality have usually been provided by cord blood banks (CBBs), but it is unclear whether pre-freezing tests or pre-transplant release tests performed by CBBs are reproducible. The aim of this study was to compare the UCB characteristics analyzed at the site of infusion of the UCB with those provided by CBBs. Samples were taken from 54 UCB units for assessment of post-thaw characteristics. TNC counts and CD34(+) cell contents measured at our hospital before infusion showed good correlations with values assessed in pre-freezing tests (r = 0.900 and 0.943, respectively) and pre-transplant release tests (r = 0.829 and 0.930, respectively). Our data reveal that the TNC counts and CD34(+) cell contents determined by pre-freezing and pre-transplant release tests, which are the most important UCB unit selection criteria, accurately reflected the quality of infused UCB units. However, CFU-GM content was poorly correlated (r = 0.560 and 0.606). Correlation of post-thaw cell viabilities measured before infusion and during the pre-transplant release tests was also poor (r = 0.308). We suggest that the TNC count and CD34(+) cell content estimated before cryopreservation and in pre-transplant release tests provided by CBBs are reproducible and can assist the transplant physicians in selection of appropriate UCB units.