Diagnosis Procedure Combination Data Research Articles

Relationship Between Unit Characteristics and Fall Incidence: A Cross-Sectional Survey Using Administrative Data in Japan.

Falls are the most frequent accident experienced by inpatients in hospitals. As falls affect patient outcomes, high fall risk factors should be studied to prevent falls and improve patient safety. However, the relationship between hospital unit characteristics and fall risk has never been assessed. This study was designed to identify the unit characteristics significantly related to fall risk. A cross-sectional study was conducted on the medical records of patients hospitalized in a Japanese academic hospital between 2018 and 2019. This study quantified unit activities and utilized Diagnosis Procedure Combination data to examine unit characteristics related to falls based on unit day. Data on 16,307 patients were included in the analysis, and 355 unit days were certified as fall events. Based on patient condition and medical treatment, the results identified antineoplastic injections, radiation therapy, aseptic treatment room, and functional status of partly assisted transfers, meals, and oral care as unit characteristics associated with increased fall events. Decreased nursing time per patient at night (odds ratio [OR] = 0.75, p = .04) and higher numbers of partially assisted transfer patients were also identified as unit characteristics associated with higher fall incidence rates (OR = 5.56, p = .01). The results of this study are expected to assist nurses to predict falls based on unit characteristics; reducing nursing time in the units was found to be a factor associated with higher fall risk. Nurse managers must understand the unit-related fall risk factors, appropriately assign nurse staffing numbers, and demonstrate nursing leadership to prevent falls in their units.

Relationship of oral bacterial number with medical hospitalization costs in analysis of Diagnosis Procedure Combination database from single institution in Japan

Oral bacteria are known to be associated with perioperative complications during hospitalization. However, no presented reports have clarified the relationship of oral bacterial number with medical costs for inpatients. The Diagnosis Procedure Combination (DPC) database system used in Japan provides clinical information regarding acute hospital patients. The present study was conducted to determine the association of oral bacterial numbers in individual patients treated at a single institution with length of hospital stay and medical costs using DPC data. A total of 2369 patients referred by the medical department to the dental department at Hiroshima University Hospital were divided into the low (n = 2060) and high (n = 309) oral bacterial number groups. Length of hospital stay and medical costs were compared between the groups, as well as the associations of number of oral bacteria with Charlson comorbidity index (CCI)-related diseases in regard to mortality and disease severity. There was no significant difference in hospital stay length between the low (24.3 ± 24.2 days) and high (22.8 ± 20.1 days) oral bacterial number groups. On the other hand, the daily hospital medical cost in the high group was significantly greater (US$1456.2 ± 1505.7 vs. US$1185.7 ± 1128.6, P < 0.001). Additionally, there was no significant difference in CCI score between the groups, whereas the daily hospital medical costs for patients in the high group treated for cardiovascular disease or malignant tumors were greater than in the low number group (P < 0.05). Multivariate regression analysis was also performed, which showed that oral bacterial number, age, gender, BMI, cardiovascular disease, diabetes, malignant tumor, and hospital stay length were independently associated with daily hospitalization costs. Monitoring and oral care treatment to lower the number of oral bacteria in patients affected by cardiovascular disease or cancer may contribute to reduce hospitalization costs.

A Reduction in the Number of Hospitalized Cases of Acute Meningitis during the COVID-19 Pandemic in Japan.

Objective The changes in the prevalence of acute meningitis during the coronavirus disease 2019 (COVID-19) pandemic remain unclear. This study aimed to compare the prevalence of acute meningitis before and during the COVID-19 pandemic in Japan. Methods We retrospectively reviewed the Japanese nationwide administrative medical payment system database, Diagnosis Procedure Combination (DPC), from 2016 to 2022. A total of 547 hospitals consistently and seamlessly offered DPC data during this period. The study period was divided into the following three periods: April 2016 to March 2018 (fiscal years 2016-2017), April 2018-March 2020 (2018-2019), and April 2020-March 2022 (2020-2021). Results Among the 28,161,806 patients hospitalized during the study period, 28,399 were hospitalized for acute meningitis: 16,678 for viral/aseptic type, 6,189 for bacterial type, 655 for fungal type, 429 for tuberculous, 2,310 for carcinomatous type, and 2,138 for other or unknown types of meningitis. A significant decrease during the pandemic was confirmed in viral (n=7,032, n=5,775, and n=3,871 in each period; p<0.0001) and bacterial meningitis (n=2,291, n=2,239, and n=1,659; p<0.0001) cases. Meanwhile, no decrease was observed in fungal meningitis (n=212, n=246, and n=197; p=0.056) or carcinomatous meningitis (n=781, n=795, and n=734; p=0.27). The decrease in the number of tuberculous meningitis cases was equivocal (n=166, n=146, and n=117; p=0.014). The decrease during the pandemic was more remarkable in younger populations aged <50 years than in older populations, both for viral and bacterial meningitis. Conclusion The number of hospitalized cases of acute meningitis clearly decreased during the COVID-19 pandemic, especially for viral and bacterial meningitis in younger populations aged <50 years.

Association Between Arterial Pulse Waveform Analysis and Mortality in Patients With Septic Shock: A Retrospective Cohort Study Using Japanese Diagnosis Procedure Combination Data.

Purpose: Specialized pressure transducers for arterial pulse waveform analysis (S-APWA) devices are dedicated kits connected to an arterial pressure catheter that monitors hemodynamic parameters, such as cardiac output, pulse pressure variation, and stroke volume variation, less invasively. While the association between the use of S-APWA devices and clinical outcomes in perioperative patients has been previously evaluated, its assessment in patients with septic shock remains inadequate. Materials and Methods: This retrospective cohort study utilized a nationwide Diagnosis Procedure Combination database in Japan. Adult patients with septic shock admitted to the intensive care unit (ICU) with arterial pressure catheter placement on the admission day from August 2012 to February 2021 were included. Hospitalizations meeting the eligibility criteria were categorized into groups based on S-APWA device usage. The primary outcome, evaluated using Cox regression analysis, was 30-day all-cause mortality in the propensity score overlap-weighted population. Secondary outcomes included in-hospital mortality, ICU duration, and overall hospital stay. Results: Among 5130 eligible hospitalizations, 643 were in the S-APWA group and 4487 were in the conventional pressure transducer group. Cox regression analysis within the propensity score overlap-weighted population showed no significant difference in 30-day mortality (adjusted hazard ratio: 0.94; 95% confidence interval: 0.9-1.38; P = .58). Logistic regression analysis indicated no significant differences in the in-hospital mortality. While the S-APWA group had prolonged ICU stays, no significant difference in the overall hospital stay was observed according to linear regression analyses. Conclusions: Our study found no significant association between S-APWA use and 30-day mortality in patients with septic shock. These findings offer insights into optimizing monitoring systems in ICUs.

Comparable Psychotropic Prescription Rates After Hospital Discharge Between Patients with COVID-19 and Those With Non-COVID-19-Related Respiratory Infection.

Whether psychiatric symptoms after recovery from coronavirus disease 2019 (COVID-19) are specific to this illness remains unclear. In this retrospective study, the Diagnosis Procedure Combination data and outpatient clinic data were used for patients who received inpatient treatment in Saiseikai-affiliated hospitals for COVID-19 or other respiratory tract infections (non-COVID) from 2020 to 2022. The primary outcome was new prescriptions of psychotropic drugs after discharge (i. e., prescriptions of psychotropics to patients who had not received them before or during their hospitalization). Values of interest were compared between groups using the chi-square test or Fisher's exact test. A COX proportional-hazards model was used to examine factors associated with psychotropic prescriptions after discharge in age- and sex-matched COVID-19 and non-COVID patients. Of 31,993 chart records, 19,613 were excluded due to a positive history with psychiatric disorders (n=2,445), prescriptions of psychotropics (n=744), and no follow-ups (n=16,424). Thus, 3,648 COVID-19 and 8,732 non-COVID patients were included (mean [range] duration of follow-up, days: 146.9 [1-727] and 239.2 [1-729], respectively). Two hundred and four (5.6%) of the 3,648 patients with COVID-19 received psychotropic prescriptions after discharge. No statistically significant differences were observed in the prescription rates of any psychotropic category between the COVID-19 and non-COVID groups. An increase in severity during hospitalization was significantly associated with more frequent psychotropic prescriptions (hazard ratio 1.83, p<0.001). The development of psychiatric symptoms should be closely observed, especially in patients who experienced increased severity during hospitalization, regardless of whether they suffered from COVID-19.

Seasonal variation of surgically treated distal radius fracture in Japan using inpatient database: cross-sectional study.

The purpose of this study was to clarify the relationship between seasonal variation and distal radius fractures using diagnosis procedure combination data in Japan. The participants were hospitalized patients who underwent surgical treatment for distal radius fracture as the primary injury at hospitals that introduced the diagnosis procedure combination system between April 2011 and March 2016. We obtained a summary table of the month of admission, region of residence, age at admission, and sex of the patients from the Ministry of Health, Labour and Welfare and evaluated it by month, region, age group, and sex. The total number of patients for the 5years from 2011 to 2016 was 105,025. There were 29,224 male and 75,801 female participants, with a female-to-male ratio of 2.6. The mean age was 60.2 (standard deviation, 20.8) years. Distal radius fractures occurred more frequently in the winter, especially among female individuals in eastern Japan. Female participants aged ≥ 50years tended to have a higher incidence of distal radius fracture in winter. The incidence of distal radius fracture among male participants aged 0-19years was higher from spring to autumn. Surgically treated distal radius fractures occur frequently during the winter months among female individuals in eastern Japan or those aged ≥ 50years and increase from school age to adolescence, especially in male individuals from spring to autumn. We should be aware of the high incidence of distal radius fractures in winter, especially in regions with snowfall and cold temperatures.

Real-world prescription of anti-COVID-19 drugs in hospitalized patients with COVID-19 in Japan.

Prescription trends and patterns of anti-COVID-19 drugs in hospitalized patients were examined based on real world data to understand the use of anti-COVID-19 drugs in clinical practice in Japan. The longitudinal and cross-sectional study was conducted utilizing data from January 1, 2019 to December 31, 2021 of the MID-NET® medical information database, which stored the electronic medical records, administrative claim data, and diagnosis procedure combination data of patients in Japan. Hospitalized patients with a COVID-19-related diagnosis who received at least one anti-COVID-19 drug between April 1, 2020 and December 31, 2021. The following 14 drugs were included in this study: remdesivir, baricitinib, combination product of casirivimab and imdevimab, favipiravir, dexamethasone, ivermectin, azithromycin, nafamostat mesylate, camostat mesylate, ciclesonide, tocilizumab, sarilumab, combination product of lopinavir and ritonavir, and hydroxychloroquine. We identified 5,717 patients hospitalized with COVID-19 and prescribed at least one anti-COVID-19 drug. The entire cohort generally included patients over 41-50 years and more males. The most common prescription pattern was dexamethasone monotherapy (22.9%), followed by the concomitant use of remdesivir and dexamethasone (15.0%), azithromycin monotherapy (15.0%), remdesivir monotherapy (10.2%), and nafamostat mesylate monotherapy (8.5%). However, an often prescribed anti-COVID-19 drug differed depending on the period. This study revealed the real-world situation of anti-COVID-19 drug prescriptions in hospitalized COVID-19 patients in Japan. A prescribed drug would depend on the latest scientific evidence, such as efficacy, safety, and approval status, at the time of prescription. Understanding the prescription of anti-COVID-19 drugs will be important for providing the most up-to-date treatments to patients and evaluating the benefit and/or risk of anti-COVID-19 drugs based on the utilization of an electronic medical record database.

Association between Cognitive Impairment Severity and Polypharmacy in Older Patients with Atrial Fibrillation: A Retrospective Study Using Inpatient Data from a Specialised Geriatric Hospital.

This study aimed to investigate the association between cognitive impairment and polypharmacy in patients with atrial fibrillation prone to cognitive decline, and to elucidate if the Dementia Assessment Sheet for Community-based Integrated Care System 21-Items (DASC-21) severity classification indicates drug adjustment. This retrospective cohort study used the DASC-21 and Diagnosis Procedure Combination data at a specialised geriatric hospital with patients hospitalised between April 2019 and March 2022. The association between cognitive severity evaluated using the DASC-21 and polypharmacy was investigated using a multivariate logistic regression model. Data of 1191 inpatients (44.3% aged ≥85 years, 49.0% male) were analysed. Compared with severe cognitive impairment, mild (odds ratio [OR]: 3.33, 95% confidence interval [CI]: 1.29-8.57) and moderate (OR: 2.46, 95% CI: 1.06-5.72) impairments were associated with concurrent use of ≥6 medications. Antithrombotics were related to polypharmacy. The ORs did not change with 6, 8, or 10 medications (2.11 [95% CI: 1.51-2.95, p < 0.001], 2.42 [95% CI: 1.79-3.27, p < 0.001], and 2.01 [95% CI: 1.46-2.77, p < 0.001], respectively). DASC-21 severity was associated with polypharmacy in patients with atrial fibrillation, with a trend toward decreased polypharmacy from moderate to severe. The DASC-21 may serve as an indicator for drug adjustment in clinical practice.

In-Hospital Mortality in Patients With Cardiogenic Shock Requiring Veno-Arterial Extracorporeal Membrane Oxygenation With Concomitant Use of Impella vs. Intra-Aortic Balloon Pump - A Retrospective Cohort Study Using a Japanese Claims-Based Database.

Patients with refractory cardiogenic shock (CS) necessitating peripheral veno-arterial extracorporeal membrane oxygenation (VA-ECMO) often require an intra-aortic balloon pump (IABP) or Impella for unloading; however, comparative effectiveness data are currently lacking.Methods and Results: Using Diagnosis Procedure Combination data from approximately 1,200 Japanese acute care hospitals (April 2018-March 2022), we identified 940 patients aged ≥18 years with CS necessitating peripheral VA-ECMO along with IABP (ECMO-IABP; n=801) or Impella (ECPella; n=139) within 48 h of admission. Propensity score matching (126 pairs) indicated comparable in-hospital mortality between the ECPella and ECMO-IABP groups (50.8% vs. 50.0%, respectively; P=1.000). However, the ECPella cohort was on mechanical ventilator support for longer (median [interquartile range] 11.5 [5.0-20.8] vs. 9.0 [4.0-16.8] days; P=0.008) and had a longer hospital stay (median [interquartile range] 32.5 [12.0-59.0] vs. 23.0 [6.3-43.0] days; P=0.017) than the ECMO-IABP cohort. In addition, medical costs were higher for the ECPella than ECMO-IABP group (median [interquartile range] 9.09 [7.20-12.20] vs. 5.23 [3.41-7.00] million Japanese yen; P<0.001). Our nationwide study could not demonstrate compelling evidence to support the superior efficacy of Impella over IABP in reducing in-hospital mortality among patients with CS necessitating VA-ECMO. Further investigations are imperative to determine the clinical situations in which the potential effect of Impella can be maximized.

Epidemiologic evaluation of pulmonary paragonimiasis in Japan using a Japanese nationwide administrative database

BackgroundParagonimiasis is a parasitic disease primarily contracted through consumption of undercooked freshwater crustaceans or wild boar meat. Large-scale nationwide epidemiological data on paragonimiasis are lacking. In this study, we aimed to investigate the nationwide epidemiology of hospitalized patients with paragonimiasis in Japan using a comprehensive nationwide Japanese administrative database. MethodsWe evaluated the Japanese Diagnosis Procedure Combination (DPC) data of patients diagnosed with pulmonary paragonimiasis between April 1, 2012 and March 30, 2020. The patients’ address and information, including age, sex, treatment (medication: praziquantel; surgery: open thoracotomy or intracranial mass extirpation), Japan coma scale, comorbidities, and length of hospital stay, were extracted. ResultsOf the 49.6 million hospitalized patients, data were extracted on 73 patients with paragonimiasis, of whom 36 were male and 37 were female. The mean age was 49.7 years and the mean length of stay was 12.5 days. The most frequent comorbidity was pleural effusion (31.5 %), followed by pneumothorax (13.7 %). The sites of ectopic paragonimiasis in organs other than the lung included the liver (5.5 %), skin (4.1 %), and brain (2.7 %). Geographically, most patients were from the Kyushu region (54.8 %), followed by the Kanto region (22.0 %). Fukuoka Prefecture had the highest number of patients (22.0 %) by prefecture. During the study period, an average of 9.1 patients/year were hospitalized with lung paragonimiasis in Japan. ConclusionParagonimiasis has not completely disappeared in Japan; thus, physicians should be aware of paragonimiasis in the Kyushu region, especially in the Fukuoka Prefecture.

Therapeutic interventions and the length of hospital stay for pediatric patients with COVID-19: a multicenter cohort study

The evidence for pediatric patients with COVID-19 was very limited, which was attributed to the small number of the cases as well as the rare incidence of severe pneumonia in this population. This retrospective cohort study aimed to identify the characteristics of pediatric patients with COVID-19 in the early period of the pandemic by analyzing Diagnosis Procedure Combination (DPC) data in Japan. This retrospective cohort analysis of Japanese multicenter research on COVID-19 using DPC data compared the outcomes and costs of treatment for pediatric patients with COVID-19. Of 4700 patients with COVID-19, 186 pediatric patients were included in this study. Among the included pediatric patients, 17 received therapeutic drugs specifically for COVID-19, while the remaining 169 pediatric patients received only symptomatic therapy. There were no significant differences in the length of hospital stay (9 vs. 8 days, p = 0.96), and medical cost (97,585 vs. 73,291 JPY) for the intervention and control groups, respectively by multiple regression analysis. This is the first epidemiological study to use DPC data to summarize the pathophysiology of pediatric patients in the early period of COVID-19 pandemic. There was no significant difference in length of hospital stay or medical cost by intervention.

Changes in surgery rates among hospitalized patients with inflammatory bowel disease in Japan from 2015 to 2019: A nationwide administrative database analysis.

Treatment of inflammatory bowel disease (IBD), consisting of ulcerative colitis (UC) and Crohn's disease (CD), has advanced with the application of biologics or Janus kinase inhibitor (JAKi); however, some patients still need surgery. We assessed time trends of surgery and biologics or JAKi variety in Japan. Patients hospitalized due to IBD were analyzed using Diagnosis Procedure Combination data between 2015 and 2019. Longitudinal trend analysis was performed for demographics, and interrupted time-series analysis was performed to examine the association between surgery rates and an increase in the types of biologics or JAKi. Totally, 37867 cases with UC and 35493 cases with CD were analyzed. Over 5years, the surgery rate decreased in both UC and CD. The proportion of biologics and JAKi usage increased in UC and stabilized in CD. Between decreasing surgery and expanding treatment options of biologic or JAKi, interrupted time-series analysis results showed no significant correlation (level change in UC, -1.13, 95% confidence interval [CI]: -2.11 to -0.16, P=0.0235; slope change in UC, -0.05, 95% CI: -0.26 to 0.16, P=0.6372; level change in CD, -0.55, 95% CI: -1.82 to 0.71, P=0.3815; slope change in CD, -0.22, 95% CI: -0.63 to 0.19, P=0.2892). In Japan, from 2015 to 2019, the use of biologics or JAKi increased for UC and slightly decreased for CD, while the number of surgeries decreased in both. Our findings suggest that more widespread use of biologics or JAKi therapy could reduce surgeries in patients with IBD.

Inventory of real-world data sources in Japan: Annual survey conducted by the Japanese Society for Pharmacoepidemiology Task Force.

The Database Task Force of the Japan Society for Pharmacoepidemiology began its annual surveys of databases available for clinico and pharmacoepidemiological studies in 2010. In this report, we summarize the characteristics of the databases available in Japan based on the results of our 2021 survey to illustrate the recent developments in the infrastructure for database research in Japan. We included 20 major databases from the academia, government, or industry that were accessible to third parties. We used a web-based questionnaire to ask the database providers about their characteristics, such as their organization, data source(s), numbers of individuals enrolled, age distribution, code(s) used, and average follow-up periods. We received responses from all 20 databases approached: eight hospital-based databases, six insurer-based databases, four pharmacy-based databases, and two in the "other" category. Among them, 17 contained information from medical claims, pharmacy claims, and/or Diagnosis Procedure Combination data. Most insurer databases contained health check-up data that could be attached to the claims component. Some hospital-based databases had data from electronic medical records. Most insurer-based databases collected data from the insurers of working-age employees and therefore had limited coverage of older people. Most databases coded their medication data using the Japanese reimbursement codes, and many provided Anatomical Therapeutic Chemical Classification codes. The number of databases available for clinico and pharmacoepidemiological research and the proportion of the population they cover are increasing in Japan. The differences in their characteristics mean that the appropriate database must be selected for a particular study purpose.

Validation Study of Diabetes Definitions Using Japanese Diagnosis Procedure Combination Data Among Hospitalized Patients.

Validation studies of diabetes definitions using nationwide healthcare databases are scarce. We evaluated the validity of diabetes definitions using disease codes and antidiabetic drug prescriptions in the Japanese Diagnosis Procedure Combination (DPC) data via medical chart review. We randomly selected 500 records among 15,334 patients who participated in the Japan Public Health Center-Based Prospective Study for the Next Generation in Yokote City and who had visited a general hospital in Akita between October 2011 and August 2018. Of the 500 patients, 98 were linked to DPC data; however, only 72 had sufficient information in the medical chart. Gold standard confirmation was performed by board-certified diabetologists. DPC-based diabetes definitions were based on the International Classification of Diseases, 10th Revision codes and antidiabetic prescriptions. Sensitivity, specificity, and the positive and negative predictive values (PPV and NPV, respectively) of DPC-based diabetes definitions were evaluated. Of 72 patients, 23 were diagnosed with diabetes using chart review; 19 had a diabetes code, and 13 had both a diabetes code and antidiabetic prescriptions. The sensitivity, specificity, PPV, and NPV were 89.5% (95% confidence interval [CI], 66.9-98.7%), 96.2% (95% CI, 87.0-99.5%), 89.5% (95% CI, 66.9-98.7%), and 96.2% (95% CI, 87.0-99.5%), respectively, for (i) diabetes codes alone; 89.5% (95% CI, 66.9-98.7%), 94.3% (95% CI, 84.3-98.8%), 85.0% (95% CI, 62.1-96.8%), and 96.2% (95% CI, 86.8-99.5%) for (ii) diabetes codes and/or prescriptions; 68.4% (95% CI, 43.4-87.4%), 100% (95% CI, 93.3-100%), 100% (95% CI, 75.3-100%), and 89.8% (95% CI, 79.2-96.2%) for (iii) both diabetes codes and prescriptions. Our results suggest that DPC data can accurately identify diabetes among inpatients using (i) diabetes codes alone or (ii) diabetes codes and/or prescriptions.

Survey of psychiatric symptoms among inpatients with COVID-19 using the Diagnosis Procedure Combination data and medical records in Japan

Physical symptoms such as fatigue and muscle weakness, and psychiatric symptoms like depression and anxiety are considered as complications and sequelae of COVID-19. This epidemiological study investigated the actual status of psychiatric symptoms and disorders caused by COVID-19, from four major university hospitals and five general hospitals in Fukuoka Prefecture, Japan, having a population of 5 million. We conducted a survey of psychiatric disorders associated with COVID-19 using Diagnosis Procedure Combination (DPC) data and the psychiatric records of the hospitals. In the study period from January 2019 to September 2021, 2743 COVID-19 admissions were determined from DPC data across the nine sites. These subjects had significantly more anxiety, depression, and insomnia, and were receiving higher rates of various psychotropic medications than controls influenza and respiratory infections. A review of psychiatric records revealed that the frequency of organic mental illness with insomnia and confusion was proportional to the severity of COVID-19 infection and that anxiety symptoms appeared independent of infection severity. These results indicate that COVID-19 is more likely to produce psychiatric symptoms such as anxiety and insomnia than conventional infections.

Validation study on definition of cause of death in Japanese claims data.

Identifying the cause of death is important for the study of end-of-life patients using claims data in Japan. However, the validity of how cause of death is identified using claims data remains unknown. Therefore, this study aimed to verify the validity of the method used to identify the cause of death based on Japanese claims data. Our study population included patients who died at two institutions between January 1, 2018 and December 31, 2019. Claims data consisted of medical data and Diagnosis Procedure Combination (DPC) data, and five definitions developed from disease classification in each dataset were compared with death certificates. Nine causes of death, including cancer, were included in the study. The definition with the highest positive predictive values (PPVs) and sensitivities in this study was the combination of "main disease" in both medical and DPC data. For cancer, these definitions had PPVs and sensitivities of > 90%. For heart disease, these definitions had PPVs of > 50% and sensitivities of > 70%. For cerebrovascular disease, these definitions had PPVs of > 80% and sensitivities of> 70%. For other causes of death, PPVs and sensitivities were < 50% for most definitions. Based on these results, we recommend definitions with a combination of "main disease" in both medical and DPC data for cancer and cerebrovascular disease. However, a clear argument cannot be made for other causes of death because of the small sample size. Therefore, the results of this study can be used with confidence for cancer and cerebrovascular disease but should be used with caution for other causes of death.

Validity of diagnoses of respiratory diseases recorded in a Japanese administrative database

BackgroundValidating the information recorded in administrative databases is essential. However, no study has comprehensively validated the accuracy of Japanese Diagnosis Procedure Combination (DPC) data on various respiratory diseases. Therefore, this study aimed to evaluate the validity of diagnoses of respiratory diseases in the DPC database. MethodsWe conducted chart reviews of 400 patients hospitalized in the departments of respiratory medicine in two acute-care hospitals in Tokyo, between April 1, 2019 and March 31, 2021, and used them as reference standards. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of DPC data on 25 respiratory diseases were determined. ResultsSensitivity ranged from 22.2% (aspiration pneumonia) to 100% (chronic eosinophilic pneumonia and malignant pleural mesothelioma) and was <50% for eight diseases, while specificity was >90% for all diseases. PPV ranged from 40.0% (aspiration pneumonia) to 100% (coronavirus disease 2019, bronchiectasis, chronic eosinophilic pneumonia, pulmonary hypertension, squamous cell carcinoma, small cell carcinoma, lung cancer of other histological types, and malignant pleural mesothelioma) and was >80% for 16 diseases. Except for chronic obstructive pulmonary disease (82.9%) and interstitial pneumonia (other than idiopathic pulmonary fibrosis) (85.4%), NPV was >90% for all diseases. These validity indices were similar in both hospitals. ConclusionsThe validity of diagnoses of respiratory diseases in the DPC database was high in general, thereby providing an important basis for future studies.

Impact of the COVID-19 pandemic on the incidence of healthcare facility-onset Clostridioides difficile infection in hospitalized patients with sepsis: Interrupted time series analysis using Japanese Diagnosis Procedure Combination data

ObjectivesHealthcare facility-onset Clostridioides difficile infection (HO-CDI) is a major nosocomial infection associated with high mortality and healthcare costs. We aimed to determine if HO-CDI incidence decreased due to the COVID-19 pandemic. We hypothesized that the pandemic decreased HO-CDI as healthcare workers became more diligent in handwashing and sanitization. MethodsIn this retrospective cohort study, adult patients with sepsis hospitalized in general wards from January 2018 to February 2021 were identified using a nationwide Japanese administrative database. Patients were divided into two groups according to the hospitalization date (before and after the first declaration of a state of emergency). The primary outcome was a change in the level of the HO-CDI monthly incidence ratio (per 10000 patient-days). ResultsOf the 49,156 eligible hospitalizations for sepsis, 41,870 were before and 7,283 were after the first state of emergency declaration. Interrupted time-series (ITS) analysis showed no significant difference in the HO-CDI incidence ratio after Japan's first state of emergency declaration (level change −1.0, 95% confidence interval (CI) −8.6 to 6.6, p = 0.8, slope change 0.06, 95% CI -0.17 to 0.3, p = 0.6). The overall HO-CDI incidence ratio was 3.86/10000 patient-days (interquartile range 2.97–4.53); higher incidence existed in subgroups with older adults or a lower Barthel index at admission. ConclusionsNo significant change in HO-CDI incidence was observed in patients with sepsis hospitalized in general wards before and after Japan's first state of emergency declaration. Our study revealed that HO-CDI in general wards in Japan had been consistently decreasing since before the COVID-19 pandemic.

Real-world evidence on disseminated intravascular coagulation from Japan.

Many descriptive epidemiological and comparative studies using big data have been reported recently from outside Japan. Within Japan, diagnosis procedure combination (DPC) data and medical receipt data are being stored in electronic media, and real-world evidence in various fields has started to be reported. We reviewed clinical studies on disseminated intravascular coagulation (DIC) using DPC data obtained from an insurance database with large numbers of cases and a related commercially available dataset including DPC and laboratory data. After DPC was introduced in 2003, 19 studies on DIC using Japanese national DPC data and two studies using the Medical Data Vision database were reported. Epidemiological findings in seven studies showed that the proportion of drugs administered for each underlying disease differed, with antithrombin and recombinant thrombomodulin (rTM) being used more frequently in clinical settings. In 14 comparative studies on anti-DIC agents, antithrombin for severe pneumonia, postoperative intestinal perforation, and severe burn, and rTM for acute cholangitis were associated with improved survival rates. Large-scale observational studies using big data can show results similar to those of randomized control trials if the quality of individual research is high. Real-world data analysis will be increasingly necessary to complement the evidence gap unfilled by randomized control trials.

The Current Status of Suicide and Medical Care System in Japan: An Analysis of 81,407 Patients Using the Diagnosis Procedure Combination Database.

Japan has a high suicide mortality rate compared to other developed countries. To reduce suicide mortality in Japan, it is important to systematically analyze factors related to death of patients with suicide attempt. This study aimed to analyze the characteristics of patients with suicide attempt, and the factors related to their death using the Diagnosis Procedure Combination (DPC) data- a nationally representative inpatient database. We collected 81,407 cases of suicide attempt from 2016 to 2018 from DPC data and performed a multilevel logistic analysis of factors associated with death discharges. The analysis results showed that patients who received psychiatric liaison care had a lower mortality rate, but only 0.6% of surviving patients received psychiatric liaison care after admission. The odds ratio (OR) of death was high for hanging (28.86; p < 0.001) and jumping (16.28; p < 0.001), compared to wrist cutting. Patients without a psychiatric diagnosis were more likely to choose means such as hanging (14.1%) than those with a psychiatric disorder. The weekend cases had a higher OR of death than weekday (Wednesday as reference) cases (Friday 1.14, p = 0.011; Saturday 1.60, p < 0.001; Sunday 1.67, p < 0.001). Based on these findings, we suggest that improving the availability and quality of psychiatric care in acute care hospitals and primary care settings, as well as enhancing the emergency department system on weekends, could help reduce the mortality of suicide attempts.