Bias Due to Within-Subject Exposure Dependency With or Without Bias Due to Lack of Pairwise Exchangeability When Exposure Is Chronic in Case-Crossover and Case-Time-Control Studies: A Simulation Study.

The case-crossover study design has been proposed as a suitable design for use when a brief exposure causes a transient change in risk of an acute-onset disease. In pharmacoepidemiology, the condition of "brief exposure" is rarely satisfied because medication use is often chronic or successive, which may result in bias due to within-subject exposure dependency. Here we describe a simulation of a case-crossover study conducted within a cohort, where patients successively used a drug for 60 or more days and the rate ratio for the outcome occurrence was 4.0. Standard conditional logistic regression for the analysis produced overestimated odds ratios ranging up to 7.8. This bias due to within-subject exposure dependency from chronic use can be removed by the Mantel-Haenszel method or by our recently proposed weighting method. We also show that when some patients are censored after switching to another drug, a lack of pairwise exchangeability causes bias which is similar to bias due to an exposure time trend. This bias can be removed by using the case-time-control study design. We show that bias due to within-subject exposure dependency and lack of pairwise exchangeability occur independently and can occur separately or simultaneously, and we demonstrate how to detect and remove them.

Metabolic events associated with the use of antipsychotics in children, adolescents and young adults: a multinational sequence symmetry study.

It is known that younger patients treated with antipsychotics are at increased risk of metabolic events; however, it is unknown how this risk varies according to ethnicity, the class of antipsychotic and the specific product used, and by age group. We conducted a multinational sequence symmetry study in Asian populations (Hong Kong, Japan, Korea, Taiwan and Thailand) and non-Asian populations (Australia and Denmark) to evaluate the metabolic events associated with antipsychotics in both Asian and non-Asian populations, for typical and atypical antipsychotics, and by the subgroups of children and adolescents, and young adults. Patients aged 6-30 years newly initiating oral antipsychotic drugs were included. We defined a composite outcome for metabolic events which included dyslipidemia, hypertension and hyperglycemia. We calculated the sequence ratio (SR) by dividing the number of people for whom a medicine for one of the outcome events was initiated within a 12-month period after antipsychotic initiation by the number before antipsychotic initiation. This study included 346,904 antipsychotic initiators across seven countries. Antipsychotic use was associated with an increased risk of composite metabolic events with a pooled adjusted SR (ASR) of 1.22 (95% CI 1.00-1.50). Pooled ASRs were similar between Asian (ASR, 1.22; 95% CI 0.88-1.70) and non-Asian populations (ASR, 1.22; 95% CI 1.04-1.43). The pooled ASR for typical and atypical antipsychotics was 0.98 (95% CI 0.85-1.12) and 1.24 (95% CI 0.97-1.59), respectively. No difference was observed in the relative effect in children and adolescents compared to young adults. The risk of metabolic events associated with antipsychotics use was similar in magnitude in Asian and non-Asian populations despite the marked difference in drug utilization patterns.

A novel weighting method to remove bias from within-subject exposure dependency in case-crossover studies.

BACKGROUND: Case-crossover studies have been widely used in various fields including pharmacoepidemiology. Vines and Farrington indicated in 2001 that when within-subject exposure dependency exists, conditional logistic regression can be biased. However, this bias has not been well studied. METHODS: We have extended findings by Vines and Farrington to develop a weighting method for the case-crossover study which removes bias from within-subject exposure dependency. Our method calculates the exposure probability at the case period in the case-crossover study which is used to weight the likelihood formulae presented by Greenland in 1999. We simulated data for the population with a disease where most patients receive a cyclic treatment pattern with within-subject exposure dependency but no time trends while some patients stop and start treatment. Finally, the method was applied to real-world data from Japan to study the association between celecoxib and peripheral edema and to study the association between selective serotonin reuptake inhibitor (SSRI) and hip fracture in Australia. RESULTS: When the simulated rate ratio of the outcome was 4.0 in a case-crossover study with no time-varying confounder, the proposed weighting method and the Mantel-Haenszel odds ratio reproduced the true rate ratio. When a time-varying confounder existed, the Mantel-Haenszel method was biased but the weighting method was not. When more than one control period was used, standard conditional logistic regression was biased either with or without time-varying confounding and the bias increased (up to 8.7) when the study period was extended. In real-world analysis with a binary exposure variable in Japan and Australia, the point estimate of the odds ratio (around 2.5 for the association between celecoxib and peripheral edema and around 1.6 between SSRI and hip fracture) by our weighting method was equal to the Mantel-Haenszel odds ratio and stable compared with standard conditional logistic regression. CONCLUSION: Case-crossover studies may be biased from within-subject exposure dependency, even without exposure time trends. This bias can be identified by comparing the odds ratio by the Mantel-Haenszel method and that by standard conditional logistic regression. We recommend using our proposed method which removes bias from within-subject exposure dependency and can account for time-varying confounders.

The validity of the claims-based definition of rheumatoid arthritis evaluated in 64 hospitals in Japan.

BACKGROUND: An administrative database covering a whole population such as the national database in Japan may be used to estimate the nationwide prevalence of diseases including rheumatoid arthritis (RA) when a well-validated definition of the disease is available. In Japan, the record linkage between the administrative database and medical charts in hospitals is strictly prohibited. A "hospital-based" validation study is one of few possible validation studies where claims kept inside the study hospital are rearranged into the database structure. METHODS: We selected random samples of 19,734 patients from approximately 1.6 million patients who received medical care between February 2018 and January 2019 in one of the 64 hospitals of the Tokushukai Medical Group. We excluded patients whose observation period was less than 365 days and identified 334 patients who met the definition of "possible cases of RA" whose medical charts were then independently evaluated by two rheumatologists. In a sensitivity analysis, we assessed bias due to misclassifying some patients with RA who did not meet the definition of "possible cases of RA" as a patient with no RA. RESULTS: The kappa coefficient between the two rheumatologists was 0.80. The prevalence of RA in the study population was estimated to be 0.56%. We found that [condition code of RA] and ([any disease-modifying antirheumatic drug] or [oral corticosteroid with no systemic autoimmune diseases (other than RA) and no polymyalgia rheumatica]) had a relatively high sensitivity (approximately 73%) and a high positive predictive value (approximately 80%). In a sensitivity analysis, we found that when some patients with RA who did not meet the definition of "possible cases of RA" were misclassified as a patient with no RA, then this would lead to underestimation of the prevalence of the definition-positive patients and the adjusted prevalence. CONCLUSIONS: We recommend using the claims-based definition of RA (found in the current validation study) to estimate the prevalence of RA in Japan. We also suggest estimating the adjusted prevalence using the quantitative bias analysis method, since the prevalence of the disease in the "hospital-based" validation study is different from that in the administrative database. TRIAL REGISTRATION: The current study is not a clinical trial and hence not subject to trial registration.

Prevalence of Therapeutic Drug Monitoring for Lithium and the Impact of Regulatory Warnings: Analysis Using Japanese Claims Database.

BACKGROUND: Therapeutic drug monitoring (TDM) for lithium is recommended in guidelines; however, the prevalence of TDM for lithium is seldom reported. We have therefore investigated the prevalence of TDM for lithium and evaluated the impact of the regulatory warnings requiring routine TDM for lithium. METHODS: Monthly claims data covering around 1.7 million persons aged 20-74 years old during the period January 1, 2005, and March 31, 2015, were evaluated. All patients who had at least one prescription for lithium were selected and included to calculate the annual prevalence of TDM for lithium. Also we assessed whether the 2 regulatory warnings requiring routine TDM for lithium and issued in April 2012 and September 2012 had an impact on TDM for lithium, using segmented regression analysis. RESULTS: Between 2005 and 2014, 136,956 prescriptions of lithium were issued to 5823 patients, and the annual prevalence of TDM for lithium was 14.9% (95% confidence interval, 14.7%-15.1%). The analysis revealed that the mean prevalence increased abruptly by 6.9% (P = 0.001) after the regulatory warning in April 2012, whereas that the warning in September 2012 decreased by 1.2% (P = 0.47). There was no significant change in trends of period prevalence after the warning in April 2012 (April 2012-August 2012) compared with prevalence before the warning (April 2010-March 2012). Similarly, no significant change was observed in the trends before (April 2012-August 2012) and after (September 2012-March 2014) the subsequent warning in September 2012. CONCLUSIONS: Results showed that the prevalence of TDM for lithium was low, although TDM for lithium was strongly recommended by the guidelines. Regulatory warnings requiring compliance with the measurement of blood levels during treatment with lithium, issued twice during the five-month period, were associated with an increase in the prevalence of TDM for lithium. However, the impact of the second warning was not remarkable compared with the first warning.

Comparative safety of NSAIDs for gastrointestinal events in Asia-Pacific populations: A multi-database, international cohort study.

PURPOSE: The safety of nonsteroidal anti-inflammatory drugs (NSAIDs) commonly used in Asia-Pacific countries has had limited study. We assessed the risk of hospitalization for gastrointestinal events with loxoprofen and mefenamic acid compared with other NSAIDs in Asia-Pacific populations. METHODS: We conducted a cohort study using a distributed network with a common data model in Australia, Hong Kong, Japan, Korea, and Taiwan. We included patients who initiated diclofenac, loxoprofen, mefenamic acid, or celecoxib and followed them until their first gastrointestinal hospitalization, switch or discontinuation of medication, disenrollment, or end of database coverage. We used Cox proportional hazards models to assess hospitalization risk. RESULTS: We identified 9879 patients in Japan, 70 492 in Taiwan, 263 741 in Korea, and 246 in Hong Kong who initiated an NSAID, and 44 013 patients in Australia, a predominantly Caucasian population. The incidence of gastrointestinal hospitalization was 25.6 per 1000 person-years in Japan, 32.8 in Taiwan, 11.5 in Korea, 484.5 in Hong Kong, and 35.6 in Australia. Compared with diclofenac, the risk of gastrointestinal events with loxoprofen was significantly lower in Korea (hazards ratio, 0.37; 95% CI, 0.25-0.54) but not in Japan (1.65; 95% CI, 0.47-5.78). The risk of gastrointestinal events with mefenamic acid was significantly lower in Taiwan (0.45; 95% CI, 0.26-0.78) and Korea (0.11; 95% CI, 0.05-0.27) but not Hong Kong (2.16; 95% CI, 0.28-16.87), compared with diclofenac. CONCLUSIONS: Compared with diclofenac, loxoprofen was associated with a lower risk of gastrointestinal hospitalizations in Korea and mefenamic acid with a lower risk in Taiwan and Korea.

Positive predictive value of ICD-10 codes for acute myocardial infarction in Japan: a validation study at a single center.

BACKGROUND: In Japan, several large healthcare databases have become available for research since the early 2000's. However, validation studies to examine the accuracy of these databases remain scarce. We conducted a validation study in order to estimate the positive predictive value (PPV) of local or ICD-10 codes for acute myocardial infarction (AMI) in Japanese claims. In particular, we examined whether the PPV differs between claims in the Diagnosis Procedure Combination case mix scheme (DPC claims) and in non-DPC claims. METHODS: We selected a random sample of 200 patients from all patients hospitalized at a large tertiary-care university hospital between January 1, 2009 and December 31, 2011 who had an inpatient claim assigned a local or ICD-10 code for AMI. We used a standardized data abstraction form to collect the relevant information from an electronic medical records system. Abstracted information was then categorized by a single cardiologist as being either definite or not having AMI. RESULTS: In a random sample of 200 patients, the average age was 67.7 years and the proportion of males was 78.0%. The PPV of the local or ICD-10 code for AMI was 82.5% in this sample of 200 patients. Further, of 178 patients who had an ICD-10 code for AMI based on any of the 7 types of condition codes in the DPC claims, the PPV was 89.3%, whereas of the 161 patients who had an ICD-10 code for AMI based on any of 3 major types of condition codes in the DPC claims, the PPV was 93.8%. CONCLUSION: The PPV of the local or ICD-10 code for AMI was high for inpatient claims in Japan. The PPV was even higher for the ICD-10 code for AMI for those patients who received AMI care through the DPC case mix scheme. The current study was conducted in a single center, suggesting that a multi-center study involving different types of hospitals is needed in the future. The accuracy of condition codes for DPC claims in Japan may also be worth examining for conditions other than AMI such as stroke.

Symmetry analysis for monitoring safety of newly marketed drugs.

INTRODUCTION: A postmarketing study without a comparator group has been recognized as a problem as it provides no measure of association. Nevertheless, the design is sometimes used in company postmarketing studies particularly when the study involves the primary data collection. In this report, the "Symmetry Analysis Cohort Design" without a comparator group but with a control period is proposed. METHODS AND RESULTS: In the proposed design, the rate ratio is estimated using the method of prescription sequence symmetry analysis with slight modification so that the rate ratio can be estimated using data on subjects who have started the drug during the study period but no data on other subjects. DISCUSSION: The proposed design has an advantage that it can provide the measure of association. Another advantage common to all self-controlled methods is that the effect of the measured and unmeasured confounders is automatically canceled out when the effect is stable over the study period. Compared with the standard design with a comparator group, the proposed design also has weaknesses. For example, adjustment of confounding by the indication may be difficult when the indication is an acute condition. In addition, the rate ratio is not valid when the probability of the prescription of the drug is dependent on the occurrence of the outcome in the unexposed (pre-dose) period. The design may be used to evaluate the need for further studies although its real usefulness is to be determined in the future.

Brief Report: Databases in the Asia-Pacific Region: The Potential for a Distributed Network Approach.

BACKGROUND: This study describes the availability and characteristics of databases in Asian-Pacific countries and assesses the feasibility of a distributed network approach in the region. METHODS: A web-based survey was conducted among investigators using healthcare databases in the Asia-Pacific countries. Potential survey participants were identified through the Asian Pharmacoepidemiology Network. RESULTS: Investigators from a total of 11 databases participated in the survey. Database sources included four nationwide claims databases from Japan, South Korea, and Taiwan; two nationwide electronic health records from Hong Kong and Singapore; a regional electronic health record from western China; two electronic health records from Thailand; and cancer and stroke registries from Taiwan. CONCLUSIONS: We identified 11 databases with capabilities for distributed network approaches. Many country-specific coding systems and terminologies have been already converted to international coding systems. The harmonization of health expenditure data is a major obstacle for future investigations attempting to evaluate issues related to medical costs.

Prescription sequence symmetry analysis: assessing risk, temporality, and consistency for adverse drug reactions across datasets in five countries.

BACKGROUND: Prescription sequence symmetry analysis (PSSA) is a signal detection method for adverse drug events. Its capacity to consistently detect adverse drug events across different settings has not been tested. We aimed to determine the consistency of PSSA results for detecting positive and negative control adverse drug events across different settings. METHODS: Using a distributed network model, we analyzed prescription dispensing data using PSSA in Australia, Hong Kong, Japan, Korea, and Taiwan. Positive control was amiodarone and thyroxine, as a marker of amiodarone-induced hypothyroidism, a known adverse event with a clear temporal relationship to amiodarone initiation. Negative controls were amiodarone and allopurinol, as a marker of amiodarone-induced gout and thyroxine and allopurinol, as a marker of thyroxine-induced gout. Gout is not recorded as an adverse event in product information for either medicine. Adjusted sequence ratios (ASR) were calculated for each country. Pooled estimates were obtained by using the generic inverse variance method. RESULTS: A positive association was identified between amiodarone and thyroxine in all settings with a pooled ASR 2.63 (95% confidence interval (CI) 1.47-4.72). Temporal analysis showed the effect occurred within the first few weeks of treatment. No significant associations were found for the negative controls in any setting; pooled ASR were 0.76 (95%CI 0.62-0.93) and 0.98 (95%CI 0.85-1.12) for amiodarone-allopurinol and thyroxine-allopurinol, respectively. CONCLUSION: Despite different health settings, different populations, and different patterns of medicine utilization, PSSA gave consistent estimates across countries for a well-known positive association and two negative control adverse events.

The Current Status of Utilizing a Medication Record Handbook for Evaluating Shared Medication History: A Retrospective Study Using the Japanese National Claims Database.

While the coronavirus disease 2019 (COVID-19) pandemic has impacted medication adherence and consultation patterns, its effects on the medical practice and dispensary separation system of Japan remain unclear. Thus, the utilization of the medication record handbook (MRH) in both medical and dental areas remains uncertain. This study uses the National Database of Health Insurance Claims and Specific Health Checkups of Japan (NDB); we analyzed the separation of medication prescription and dispensing in both medicine and dentistry, as well as estimated how much drug information is shared by utilizing a patient-carried MRH. The external prescription (EP) rate was used as the main indicator. We then analyzed the MRH utilization rate during outpatient medication guidance. During the pandemic, there was no distinctive change in the rate of EPs in both medicine and dentistry. Furthermore, an analysis between EPs, medical internal prescriptions (IPs), and dental IPs relative to the MRH utilization rate revealed significant correlations between EPs and medical IPs as well as medical and dental IPs. Conversely, no significant correlation was found between EPs and dental IPs. Therefore, our results suggest that active MRH implementation within healthcare facilities may lead to an increase in its utilization in dentistry.

Metabolic predictors of ischemic heart disease and cerebrovascular attack in elderly diabetic individuals: difference in risk by age.

BACKGROUND: High LDL-cholesterol (LDL-C) and glucose levels are risk factors for ischemic heart disease (IHD) in middle-aged diabetic individuals; however, the risk among the elderly, especially the very elderly, is not well known. The aim of this study was to identify factors that predict IHD and cerebrovascular attack (CVA) in the elderly and to investigate their differences by age. METHODS: We performed a prospective cohort study (Japan Cholesterol and Diabetes Mellitus Study) with 5.5 years of follow-up. A total of 4,014 patients with type 2 diabetes and without previous IHD or CVA (1,936 women; age 67.4 ± 9.5 years, median 70 years; <65 years old, n = 1,261; 65 to 74 years old, n = 1,731; and ≥ 75 years old, n = 1,016) were recruited on a consecutive outpatient basis from 40 hospitals throughout Japan. Lipids, glucose, and other factors related to IHD or CVA risk, such as blood pressure (BP), were investigated using the multivariate Cox hazard model. RESULTS: One hundred fifty-three cases of IHD and 104 CVAs (7.8 and 5.7/1,000 people per year, respectively) occurred over 5.5 years. Lower HDL-cholesterol (HDL-C) and female gender were correlated with IHD in patients ≥75 years old (hazard ratio (HR):0.629, P < 0.01 and 1.132, P < 0.05, respectively). In contrast, systolic BP (SBP), HbA1C, LDL-C and non-HDL-C were correlated with IHD in subjects <65 years old (P < 0.05), and the LDL-C/HDL-C ratio was correlated with IHD in all subjects. HDL-C was correlated with CVA in patients ≥75 years old (HR: 0.536, P < 0.01). Kaplan-Meier estimator curves showed that IHD occurred more frequently in patients <65 years old in the highest quartile of the LDL-C/HDL-C ratio. In patients ≥75 years old, IHD and CVA were both the most frequent among those with the lowest HDL-C levels. CONCLUSIONS: IHD and CVA in late elderly diabetic patients were predicted by HDL-C. LDL-C, HbA1C, SBP and non-HDL-C are risk factors for IHD in the non-elderly. The LDL-C/HDL-C ratio may represent the effects of both LDL-C and HDL-C. These age-dependent differences in risk are important for developing individualized strategies to prevent atherosclerotic disease. TRIAL REGISTRATION: UMIN-CTR, UMIN00000516.

Multi-country rapid adverse drug event assessment: the Asian Pharmacoepidemiology Network (AsPEN) antipsychotic and acute hyperglycaemia study.

PURPOSE: To undertake a multi-country study to investigate the risk of acute hyperglycaemia with antipsychotic use. METHODS: Using a distributed network model with a common minimal data set, we performed a prescription sequence symmetry analysis (PSSA) to investigate the risk of acute hyperglycaemia associated with antipsychotic initiation. Incident insulin prescriptions were used as a proxy indicator of acute hyperglycaemia. Participating countries and population datasets included Australia (300,000 persons), Japan I (300,000 persons), Japan II (200,000 persons), Korea (53 million persons) Taiwan (1 million persons), Sweden (9 million persons), USA-Public (87 million persons) and USA-Private (47 million persons). RESULTS: Olanzapine showed a trend towards increased risk in most databases, with a significant association observed in the USA-Public database (Adjusted sequence ratio (ASR) = 1.14; 95% Confidence Interval (CI) 1.10-1.17) and Sweden (ASR = 1.53; 95% CI 1.13-2.06). Null or negative associations were observed for haloperidol, quetiapine and risperidone. CONCLUSION: Acute hyperglycaemia appears to be associated with olanzapine use, however, this effect was only observed in two large databases. Despite different patterns of utilization of both antipsychotics and insulin, PSSA analysis results for individual antipsychotic medicines were qualitatively similar across most countries. PSSA, used in conjunction with existing methods, may provide a simple and timely method further supporting multi-national drug safety monitoring.

Feasibility of Child-Resistant and Senior-Friendly Press-Through Packages: Potential of Different Materials.

Press-through packaging (PTP) is the most common type of drug packaging in Japan, and a production procedure for PTP has been established at an acceptable cost. However, unknown problems and new needs with regard to safety among users of various age-groups still need to be examined. Considering accident reports involving children and older adults, the safety and quality of PTP and new forms of PTP, such as child-resistant and senior-friendly (CRSF) packaging, should be evaluated. We conducted an ergonomic study on children and older adults to compare types of commonly used PTP and new varieties of PTP. Opening tests were attempted by children and older adults using a common type of PTP (Type A) and child-resistant (CR) PTP (Types B1 and B2) made from soft aluminum foil. The same opening test was conducted on older patients with rheumatoid arthritis (RA). The results showed that CR PTP was difficult for children to open: only 1 out of 18 children could open Type B1. On the other hand, all eight of the older adults could open Type B1, and eight patients with RA could easily open Types B1 and B2. These findings suggest that the quality of CRSF PTP can be improved with the use of new materials.

Global Epidemiology of Hip Fractures: Secular Trends in Incidence Rate, Post-Fracture Treatment, and All-Cause Mortality.

In this international study, we examined the incidence of hip fractures, postfracture treatment, and all-cause mortality following hip fractures, based on demographics, geography, and calendar year. We used patient-level healthcare data from 19 countries and regions to identify patients aged 50 years and older hospitalized with a hip fracture from 2005 to 2018. The age- and sex-standardized incidence rates of hip fractures, post-hip fracture treatment (defined as the proportion of patients receiving anti-osteoporosis medication with various mechanisms of action [bisphosphonates, denosumab, raloxifene, strontium ranelate, or teriparatide] following a hip fracture), and the all-cause mortality rates after hip fractures were estimated using a standardized protocol and common data model. The number of hip fractures in 2050 was projected based on trends in the incidence and estimated future population demographics. In total, 4,115,046 hip fractures were identified from 20 databases. The reported age- and sex-standardized incidence rates of hip fractures ranged from 95.1 (95% confidence interval [CI] 94.8-95.4) in Brazil to 315.9 (95% CI 314.0-317.7) in Denmark per 100,000 population. Incidence rates decreased over the study period in most countries; however, the estimated total annual number of hip fractures nearly doubled from 2018 to 2050. Within 1 year following a hip fracture, post-hip fracture treatment ranged from 11.5% (95% CI 11.1% to 11.9%) in Germany to 50.3% (95% CI 50.0% to 50.7%) in the United Kingdom, and all-cause mortality rates ranged from 14.4% (95% CI 14.0% to 14.8%) in Singapore to 28.3% (95% CI 28.0% to 28.6%) in the United Kingdom. Males had lower use of anti-osteoporosis medication than females, higher rates of all-cause mortality, and a larger increase in the projected number of hip fractures by 2050. Substantial variations exist in the global epidemiology of hip fractures and postfracture outcomes. Our findings inform possible actions to reduce the projected public health burden of osteoporotic fractures among the aging population. © 2023 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).

Effectiveness and Safety of Reduced and Standard Daily Doses of Direct Oral Anticoagulants in Patients with Nonvalvular Atrial Fibrillation: A Cohort Study Using National Database Representing the Japanese Population.

Purpose: To compare the effectiveness and safety of reduced or standard daily doses of direct oral anticoagulants (DOACs) with warfarin in Japanese patients with nonvalvular atrial fibrillation (NVAF). We used post-hoc analyses to identify patient groups that could benefit from reduced-dose DOACs. Patients and Methods: Using the National Database of Health Insurance Claims and Specific Health Checkups of Japan, we identified 944,776 patients with NVAF who had started an oral anticoagulant after at least one year of non-use between April 2011 and March 2016. We matched patients taking any, reduced, or standard doses of DOACs 1:1 with those taking warfarin. We measured treatment effectiveness based on admission due to stroke or systemic embolism (S/SE) and safety based on admission due to any bleeding (defined as major bleeding, MB). We compared both outcomes between DOACs and warfarin using the Cox proportional hazards model. We used post-hoc analysis to match patients receiving reduced-dose DOACs to those receiving standard-dose DOACs and compared treatment effectiveness and safety. Results: More than half of patients receiving DOACs used a reduced dose. The occurrences of S/SE and MB in patients receiving any, reduced, or standard doses of DOACs were equal to or lower than those receiving warfarin. In the post-hoc analysis, the risk of S/SE and MB was similar between reduced and standard doses of DOACs except for those with a history of cerebral infarction and CHA2DS2-VASc score ≥3, where the risk of S/SE was lower for reduced doses of any and individual DOACs. Conclusion: Findings from the current study are consistent with recent Asian and global studies but different from most studies conducted in North America and Europe, where patients receiving a reduced dose of DOACs had an increased risk of S/SE. Future studies should test the reproducibility of results from the current study.

Evaluation of Newly Designed Blister Packs for Easier Handling to Prevent Pill Dropping.

BACKGROUND: Blister packs with paperboard backing, which is useful for displaying instructions and information, are the most popular type of packaging for osteoporosis drugs in Japan. However, the main users of drugs are the aged, who often find blister packs difficult to open or drop their pills during opening. In this study, we compared different types of blister packs in terms of usability and handling. METHODS: We conducted a subjective and objective study to compare commonly used blister packs with newly designed ones that have a jagged notch designed to hold a pill temporarily and a perforated line that enables the pack to be held easily in one hand. Regarding subjective data, packaging and sensory tests were performed. The participants in the sensory test were healthy older adults and patients with rheumatoid arthritis (RA). We also measured the pinch power of all participants. RESULTS: A comparison of several items, including opening status, prevention of pill dropping, and understanding of the instructions, using a numerical rating scale revealed no significant differences between ordinary (type A) and newly designed (type B) packaging. However, the scores for type B were the same or better than those for type A for every evaluation item. In addition, more than 85% of the participants reported preferring to use type B. More than 80% of the participants in both groups reported dropping pills using type A, which seemed to be related to their preference for type B. In the evaluation by the examiner (objective study), all participants could successfully remove their pills without dropping using type B, including those in the RA group who had difficulty handling packages. CONCLUSION: These findings suggest that the new type of blister pack assessed in this study (type B) is preferable among older and shows promise for a universal design.

Age, gender, insulin and blood glucose control status alter the risk of ischemic heart disease and stroke among elderly diabetic patients.

BACKGROUND: We analyzed the effects of insulin therapy, age and gender on the risk of ischemic heart disease (IHD) and cerebrovascular accident (CVA) according to glycemic control. METHODS AND RESULTS: We performed a prospective cohort study (Japan Cholesterol and Diabetes Mellitus Study) of type 2 diabetes patients (n = 4014) for 2 years. The primary endpoint was the onset of fatal/non-fatal IHD and/or CVA, which occurred at rates of 7.9 and 7.2 per 1000 person-years, respectively. We divided diabetic patients into four groups based on age (≤ 70 and > 70) and hemoglobin A1C levels (≤ 7.0 and > 7.0%). Multiple regression analysis revealed that IHD was associated with high systolic blood pressure and low HDL-C in patients under 70 years of age with fair glycemic control and was associated with low diastolic blood pressure in the older/fair group. Interestingly, insulin use was associated with IHD in the older/poor group (OR = 2.27, 95% CI = 1.11-5.89; p = 0.026) and was associated with CVA in the older/fair group (OR = 2.09, 95% CI = 1.06-4.25; p = 0.028). CVA was associated with lower HDL-C and longer duration of diabetes in younger/poor glycemic control group. Results by stepwise analysis were similar. Next, patients were divided into four groups based on gender and diabetic control(hemoglobinA1C < or > 7.0%). Multiple regression analysis revealed that IHD was associated with high systolic blood pressure in male/fair glycemic control group, age in male/poor control group, and short duration of diabetic history in females in both glycemic control groups. Interestingly, insulin use was associated with IHD in the male/poor group(OR = 4.11, 95% CI = 1.22-8.12; p = 0.018) and with CVA in the female/poor group(OR = 3.26, 95% CI = 1.12-6.24; p = 0.02). CVA was associated with short duration of diabetes in both female groups. CONCLUSIONS: IHD and CVA risks are affected by specific factors in diabetics, such as treatment, gender and age. Specifically, insulin use has a potential role in preventing IHD but may also be a risk factor for CVA among the diabetic elderly, thus revealing a need to develop improved treatment strategies for diabetes in elderly patients. The Japan Cholesterol and Diabetes Mellitus Study was formulated to evaluate them(Umin Clinical Trials Registry, clinical trial reg. no. UMIN00000516; http://www.umin.ac.jp/ctr/index.htm).

Survival and prognostic factors in malignant pleural mesothelioma: a retrospective study of 314 patients in the west part of Japan.

OBJECTIVE: The objective in our study was to examine baseline and other characteristics associated with survival in patients with malignant pleural mesothelioma in Japan. METHODS: Three hundred and fourteen patients with an adjudicated diagnosis of mesothelioma were examined. Survival was evaluated by the Kaplan-Meier method with the log-rank test. The Cox model was used to estimate the hazard ratio for the possible prognostic factors. RESULTS: Of 314 patients, 223 (71%) died and only 40 (13%) were still alive at the end of the observation period starting from the day of diagnosis, while 51 (16%) were transferred to other hospitals or had the last health service contact before the end of the study period yielding the median survival of 308 days. In the multivariate analysis, age older than 70 years (hazard ratio = 2.17; 95% confidence interval, 1.36-3.46), non-epithelioid type (hazard ratio = 1.58; 95% confidence interval, 1.15-2.18), poor performance status (hazard ratio = 3.22; 95% confidence interval, 1.19-8.74), high white blood cell count (hazard ratio = 1.49; 95% confidence interval, 0.99-2.26) and high C-reactive protein level (hazard ratio = 1.80; 95% confidence interval, 1.06-3.06) were negatively associated with survival, after adjustment for other factors. CONCLUSIONS: Some baseline conditions including old age, poor performance status, non-epithelioid type, high white blood cell count and high C-reactive protein level were determinants of poor survival of patients with malignant mesothelioma.