The Utility and Limitations of Universal Polymerase Chain Reaction Screening for SARS-CoV-2 During Hospital Admission.

OBJECTIVE: Universal polymerase chain reaction (PCR) screening for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on hospital admission is an effective approach to preventing coronavirus disease 2019 (COVID-19) outbreaks in medical facilities. However, false-positive test results due to a recent infection are a concern. We investigated the usefulness and limitations of universal PCR screening for SARS-CoV-2 on hospital admission in a real-world setting. METHODS: We retrospectively analyzed 1320 attempted hospital admissions for 775 patients at the Department of Respiratory Medicine, Kyushu University Hospital, between January 1, 2022, and May 2, 2023. RESULTS: Thirty-nine out of 1201 PCR tests (3.2%) yielded a positive result, with 22 of these results being considered false positives on the basis of a recent infection. We found that 39% of cases showed a positive PCR result between 31 and 60 days after the onset of COVID-19, although the threshold cycle (Ct) for target 1 (ORF1ab gene) of the Cobas SARS-CoV-2 test (Roche Diagnostics, Basel, Switzerland) was >30 in most instances. CONCLUSION: Hospital admission based on the results of PCR screening for SARS-CoV-2 should take into account not only PCR positivity but also the Ct value and recent COVID-19 history.

[RECURRENT AND VIRTUAL EDUCATION FOR ALL DISCIPLINES AND OCCUPATIONS IN THE ALLERGY REALM : A SURVEY OF THE PARTICIPANTS FROM THE INITIATIVE 'OUTREACH LECTURES' TO CREATE EDUCATIONAL OPPORTUNITIES].

BACKGROUND: In the enhancement of allergy care involving multidisciplinary and multiple medical departments, there is a perceived need for education that targets not only specialists but also non-specialists. However, research on the need for and methods of such education remains inadequate. OBJECTIVE: To design a remote allergy care education program for all medical practitioners and to validate its necessity and utility. METHODS: The Empowering Next Generation Allergist/immunologist toward Global Excellence Task Force (ENGAGE-TF), supported by the Japanese Society of Allergology, initiated a virtual educational program called 'Outreach Lectures' in collaboration with Keio University and Fukui University. This initiative was widely promoted through social media and various institutions, and a survey was conducted through its mailing list. RESULTS: 1139 responses were obtained. More than half were physicians from non-allergy specialties, representing a diverse range of healthcare professions. Over 70% expressed being 'very satisfied,' and over 60% found the difficulty level 'appropriate.' Free-form feedback revealed differences in learning focus based on profession and learning approach based on years of experience. CONCLUSION: The high participation rate (90%) of non-specialist physicians underscores the demand for addressing allergic conditions in primary care. The effectiveness of virtual / recurrent education, particularly for healthcare professionals with over 11 years of experience, was implied. Further follow-up investigation focusing on quantitative and objective assessment of educational effectiveness is indispensable.

[STATE-OF-THE-ART OF GLOBAL START-UP INVESTMENT FOR ALLERGY AND IMMUNOLOGY 2022].

BACKGROUND: In 2022, the "New Capitalism Grand Design and Implementation Plan" was adopted in Japan, emphasizing the promotion and environmental development of startups. Given this context, an investigation into the startup and investment landscape in the allergy sector, both domestically and internationally, becomes imperative. METHODS: We analyzed 156 allergy-related startups from Japan, the US, and Europe from 2010 to 2021. Data on corporate information and investment trends were extracted from databases and VC websites. RESULTS: The total investment reached approximately 7.2 billion USD, with a ratio of 20:6:1 for the US, Europe, and Japan, respectively. The US showed a decline post its peak from 2016-2018, while Europe and Japan experienced growth. Notably, the US primarily invested in biopharmaceuticals for atopic dermatitis and food allergies, Europe in asthma-related apps, and Japan in healthcare apps and cross-border startups. DISCUSSION AND CONCLUSION: While Japan's investment environment in the allergy sector remains in its nascent stages and has room for development, the US and Europe are evidently ahead. Considering the rise of startups and funding limitations in Japan, external funding from regions like the US becomes a potential avenue. These findings are anticipated to contribute to the strategic activation of startups in allergy research and development.

Acute Dapagliflozin Administration Ameliorates Cardiac Surgery-Associated Acute Kidney Injury in a Rabbit Model.

BACKGROUND: Several studies have shown that sodium-glucose cotransporter-2 inhibitors have a renoprotective effect on acute kidney injury (AKI), but their effect on cardiac surgery-associated AKI is unknown.Methods and Results: AKI was induced in 25 rabbits without diabetes mellitus by cardiopulmonary bypass (CPB) for 2 h and they were divided into 5 groups: sham; dapagliflozin-treated sham; CPB; dapagliflozin-treated CPB; and furosemide-treated CPB (n=5 in each group). Dapagliflozin was administered via the femoral vein before initiating CPB. Kidney tissue and urine and blood samples were collected after the surgical procedure. There were no differences in the hemodynamic variables of each group. Dapagliflozin reduced serum creatinine and blood urea nitrogen concentrations, and increased overall urine output (all P<0.05). Hematoxylin and eosin staining showed that the tubular injury score was improved after dapagliflozin administration (P<0.01). Dapagliflozin administration mitigated reactive oxygen species and kidney injury molecule-1 as assessed by immunohistochemistry (both P<0.0001). Protein expression analysis showed improvement of inflammatory cytokines and apoptosis, and antioxidant enzyme expression was elevated (all P<0.05) through activation of the nuclear factor erythroid 2-related factor 2 pathway (P<0.01) by dapagliflozin. CONCLUSIONS: Acute intravenous administration of dapagliflozin protects against CPB-induced AKI. Dapagliflozin may have direct renoprotective effects in renal tubular cells.

Cannula to Femoral Artery Diameter Ratio Predicts Potential Lower-Limb Ischemia in Minimally Invasive Cardiac Surgery With Femoral Cannulation.

OBJECTIVE: Lower-limb ischemia is a complication of minimally invasive cardiac surgery with femoral cannulation. Herein, we verified our strategy using distal perfusion cannulation (DPC) against this complication. METHODS: We retrospectively assessed 91 cases of aortic valve replacement with femoral cannulation between January 2019 and March 2023. DPC was applied when lower-limb tissue oxygenation index declined by ≥20%. The cannula to femoral artery diameter ratio (C/FA) was calculated by dividing the cannula size (Fr) divided by 3 by the femoral artery inner diameter (mm). Postoperative maximum creatinine kinase (CKmax), lactate dehydrogenase (LDHmax), and lactate levels were analyzed, and univariable logistic regression and receiver operating characteristic curve analyses were employed to determine DPC predictors and the cutoff C/FA for DPC, respectively. Patients without DPC were divided into 2 subgroups based on the cutoff C/FA for further comparisons. RESULTS: DPC was required in 9 patients. Symptomatic ischemia was not observed. All laboratory data were similar in the DPC and non-DPC groups. C/FA was significantly associated with DPC (odds ratio = 1.27, 95% confidence interval: 1.09 to 1.47, P = 0.002), and the cutoff C/FA was 0.70 (sensitivity = 0.89, specificity = 0.80). In the non-DPC group, CKmax (P = 0.027) and LDHmax (P = 0.041) were significantly higher in patients with C/FA ≥0.7 (n = 16) than in those with C/FA <0.7 (n = 66). CONCLUSIONS: Our strategy for preventing symptomatic ischemia is reasonable and could be almost achieved without DPC when C/FA is <0.7. C/FA also predicts asymptomatic potential ischemia, and proactive DPC is preferable when C/FA is ≥0.7.

Efficacy of Sac Coil Embolization in Endovascular Aortic Repair for Sac Shrinkage in Patients at a High Risk of Type II Endoleak from Lumbar Arteries.

BACKGROUND: In endovascular aortic repair (EVAR), preemptive embolization of sac branch vessels is effective in preventing postoperative type II endoleak (T2EL). However, this technique has not been widely adopted especially for lumbar arteries (LAs) because of technical difficulties and time constraints. This study aimed to investigate the efficacy of nonselective sac coil embolization, which is a simpler surgical method, in postoperative sac shrinkage for patients at a high risk of T2EL from LAs. METHODS: We retrospectively assessed 76 patients who underwent elective EVAR for abdominal aortic aneurysm with 4 or more patent LAs or at least 1 patent LA of ≥2 mm at our hospital between January 2014 and December 2022. The patients who underwent sac coil embolization were included in Group Ⅰ (n = 20), and the others were divided into 2 groups: those with an inferior mesenteric artery that was originally occluded or embolized by coils or stent graft bodies (Group Ⅱ, n = 21), and those without that (Group Ⅲ, n = 35). In Group Ⅰ, 0.035-inch coils were inserted into the sac after complete stent graft deployment. The cumulative incidence of sac shrinkage (≥5 mm) was compared between the groups. Further, univariable and multivariable Cox regression analyses were used to determine the predictors of sac shrinkage. RESULTS: Sac shrinkage (≥5 mm) was observed more frequently in Group Ⅰ (50%) than in Group Ⅱ (19%) and Group Ⅲ (17%) (P = 0.052 and 0.043, respectively). The cumulative incidence of sac shrinkage was significantly higher in Group Ⅰ than in Group Ⅱ (log-rank P = 0.039) and Group Ⅲ (log-rank P = 0.024). Multivariable Cox regression analyses revealed that sac embolization was a significant predictor of sac shrinkage (hazard ratio, 4.23; 95% confidence interval, 1.66-10.8; P = 0.003). CONCLUSIONS: Nonselective sac coil embolization in EVAR is potentially effective for sac shrinkage in the early postoperative phase in patients at high risk of T2EL from LAs. This simple procedure may improve prognosis after EVAR.

Surfactant protein D prevents mucin overproduction in airway goblet cells via SIRPα.

Mucin overproduction is a common feature of chronic airway diseases such as asthma and chronic obstructive pulmonary disease (COPD), and exacerbates their underlying respiratory condition. Surfactant protein D (SP-D) protects against airway diseases through modulation of immune reactions, but whether it also exerts direct effects on airway epithelial cells has remained unclear. Therefore, we sought to investigate the inhibitory role of SP-D on mucin production in airway epithelial cells. We prepared air-liquid interface (ALI) cultures of human primary bronchial epithelial cells (HBECs), which recapitulated a well-differentiated human airway epithelium. Benzo(a)pyrene (BaP), a key toxicant in cigarette smoke, induced mucin 5AC (MUC5AC) production in ALI-cultured HBECs, airway secretory cell lines, and airway epithelia of mice. Then, the protective effects of SP-D against the BaP-induced mucin overproduction were examined. BaP increased MUC5AC production in ALI cultures of HBECs, and this effect was attenuated by SP-D. SP-D also suppressed the BaP-induced phosphorylation of extracellular signal-regulated kinase (ERK) and MUC5AC expression in NCI-H292 goblet-like cells, but not in NCI-H441 club-like cells. Signal regulatory protein α (SIRPα) was found to be expressed in HBECs and NCI-H292 cells but absent in NCI-H441 cells. In NCI-H292 cells, SP-D activated SH2 domain-containing tyrosine phosphatase-1 (SHP-1), downstream of SIRPα, and knockdown of SIRPα abolished the suppressive effects of SP-D on BaP-induced ERK phosphorylation and MUC5AC production. Consistent with these in vitro findings, intratracheal instillation of SP-D prevented the BaP-induced phosphorylation of ERK and Muc5ac expression in airway epithelial cells in a mouse model. SP-D acts directly on airway epithelial cells to inhibit mucin secretion through ligation of SIRPα and SHP-1-mediated dephosphorylation of ERK. Targeting of SIRPα is therefore a potential new therapeutic approach to suppression of mucin hypersecretion in chronic airway diseases such as COPD and asthma.

Insights from the trends of omalizumab and mepolizumab utilization in patients with asthma: A population-based cohort study using the National Database in Japan.

BACKGROUND: Biologics are increasingly being used in patients with severe uncontrolled asthma. However, the trends in their use for treating severe asthma in Japan remain unclear. METHODS: The number of patients with asthma prescribed omalizumab or mepolizumab between April 2017 and March 2018 was estimated according to sex, age, and geographical region using data from the National Database of Health Insurance Claims and Specific Health Checkups of Japan. RESULTS: Overall, 5,014, 3,449 and 7,977 patients were prescribed omalizumab, mepolizumab, or either combination, respectively. The total number of patients prescribed biologics displayed a bimodal distribution with peaks in their early teens and seventies. Biologics were most commonly used by male and female patients in their seventies. Prescription was 1.24 times higher in males than in females up to the teenage years, whereas it was 1.95 times higher in females than in males from their twenties onwards. Omalizumab was prescribed 1.45 times more frequently than mepolizumab, especially in pediatric patients, and was prescribed 1.96 times more often to female patients than to male patients. Regional differences were observed in the proportion of patients prescribed biologics. Correlation analysis suggested a weak relationship (r = 0.3226, p = 0.0270) between the proportion of patients prescribed biologics and board-certified allergists according to the geographic region. CONCLUSIONS: In Japan, biologics are prescribed more often to older patients with severe asthma compared to those in other countries. Thus, eliminating the regional disparities in asthma treatment by specialists is necessary to provide appropriate medical care to patients with severe asthma.

Effects of treatment with corticosteroids on human rhinovirus-induced asthma exacerbations in pediatric inpatients: a prospective observational study.

BACKGROUND: Human rhinoviruses (HRVs) infection is a common cause of exacerbations in pediatric patients with asthma. However, the effects of corticosteroids on HRV-induced exacerbations in pediatric asthma are unknown. We conducted a prospective observational study to determine the viral pathogens in school-age pediatric inpatients with asthma exacerbations. We assessed the effects of maintenance inhaled corticosteroids (ICS) on the detection rates of HRV species and treatment periods of systemic corticosteroids during exacerbations on pulmonary lung function after exacerbations. METHODS: Nasopharyngeal samples and clinical information were collected from 59 patients with asthma exacerbations between April 2018 and March 2020. Pulmonary function tests were carried out 3 months after exacerbations in 18 HRV-positive patients. Changes in forced expiratory volume in 1 second (FEV1)% predicted from baseline in a stable state were compared according to the treatment periods of systemic corticosteroids. RESULTS: Fifty-four samples collected from hospitalized patients were analyzed, and viral pathogens were identified in 45 patients (83.3%) using multiplex PCR assay. HRV-A, -B, and -C were detected in 16 (29.6%), one (1.9%), and 16 (29.6%) patients, respectively. The detection rates of HRV-C were lower in the ICS-treated group compared with those in the ICS-untreated group (p = 0.01), whereas maintenance ICS treatment did not affect the detection rate for viral pathogens in total and HRV-A. Changes in FEV1% predicted in patients treated with systemic corticosteroids for 6-8 days (n = 10; median, 4.90%) were higher than those in patients treated for 3-5 days (n = 8; median, - 10.25%) (p = 0.0085). CONCLUSIONS: Maintenance ICS reduced the detection rates of HRV (mainly HRV-C) in school-age inpatients with asthma exacerbations, and the treatment periods of systemic corticosteroids during exacerbations affected lung function after HRV-induced exacerbations. The protective effects of corticosteroids on virus-induced asthma exacerbations may be dependent upon the types of viral pathogen.

Risks of dementia in a general Japanese older population with preserved ratio impaired spirometry: The Hisayama Study.

BACKGROUND: Studies on the association between preserved ratio impaired spirometry (PRISm) and dementia are limited. Indeed, PRISm has often been overlooked or ignored as an index of lung function impairment. Therefore, we investigated the association of PRISm with the risk for the development of dementia in an older Japanese population. METHODS: A total of 1202 community-dwelling, older Japanese participants aged ≥65 years without dementia were followed up for a median of 5.0 years. Participants were categorized by spirometry as follows: normal spirometry (FEV1/FVC ≥0.70 and FEV1 ≥80% predicted), PRISm (≥0.70 and <80%), airflow limitation (AFL) Global Initiative for Chronic Obstructive Lung Disease (GOLD) 1 (<0.70 and ≥80%), and AFL GOLD 2 to 4 (<0.70 and <80%). Hazard ratios (HRs) and their 95% confidence intervals (CIs) were computed using a Cox proportional hazards model. RESULTS: During the follow-up period, 122 participants developed dementia. The age- and sex-adjusted incidences of dementia in the participants with normal spirometry, PRISm, AFL GOLD 1, and AFL GOLD 2 to 4 were 20.5, 37.0, 18.4, and 28.6 per 1000 person-years, respectively. Participants with PRISm had a higher risk of dementia (HR 2.04 [95%CI, 1.19-3.49]) than those with normal spirometry after adjusting for confounders. Moreover, both reduced FEV1% predicted values and FVC% predicted values were associated with the risk for dementia. CONCLUSION: PRISm was associated with an increased risk of dementia in a general older Japanese population.

Computational fluid-particle dynamics modeling of ultrafine to coarse particles deposition in the human respiratory system, down to the terminal bronchiole.

BACKGROUND AND OBJECTIVES: Suspended respirable airborne particles are associated with human health risks and especially particles within the range of ultrafine (< 0.1 µm) or fine (< 2.5 µm) have a high possibility of penetrating the lung region, which is concerned to be closely related to the bronchial or alveoli tissue dosimetry. Nature complex structure of the respiratory system requires much effort to explore and comprehend the flow and the inhaled particle dynamics for precise health risk assessment. Therefore, this study applied the computational fluid-particle dynamics (CFPD) method to elucidate the deposition characteristics of ultrafine-to-coarse particles in the human respiratory tract from nostrils to the 16th generation of terminal bronchi. METHODS: The realistic bronchi up to the 8th generation are precisely and perfectly generated from computed tomography (CT) images, and an artificial model compensates for the 9th-16th bronchioles. Herein, the steady airflow is simulated at constant breathing flow rates of 7.5, 15, and 30 L/min, reproducing human resting-intense activity. Then, trajectories of the particle size ranging from 0.002 - 10 µm are tracked using a discrete phase model. RESULTS: Here, we report reliable results of airflow patterns and particle deposition efficiency in the human respiratory system validated against experimental data. The individual-related focal point of ultrafine and fine particles deposition rates was actualized at the 8th generation; whilst the hot-spot of the deposited coarse particles was found in the 6th generation. Lobar deposition characterizes the dominance of coarse particles deposited in the right lower lobe, whereas the left upper-lower and right lower lobes simultaneously occupy high deposition rates for ultrafine particles. Finally, the results indicate a higher deposition in the right lung compared to its counterpart. CONCLUSIONS: From the results, the developed realistic human respiratory system down to the terminal bronchiole in this study, in coupling with the CFPD method, delivers the accurate prediction of a wide range of particles in terms of particle dosimetry and visualization of site-specific in the consecutive respiratory system. In addition, the series of CFPD analyses and their results are to offer in-depth information on particle behavior in human bronchioles, which may benefit health risk assessment or drug delivery studies.

Necrostatin-1 Attenuates Delayed Paraplegia after Transient Spinal Cord Ischemia in Rabbits by Inhibiting the Upregulation of Receptor-Interacting Protein Kinase 1 and 3.

BACKGROUND: Delayed-onset paraplegia is a disastrous complication after thoracoabdominal aortic open surgery and thoracic endovascular aortic repair. Studies have revealed that transient spinal cord ischemia caused by temporary occlusion of the aorta induces delayed motor neuron death owing to apoptosis and necroptosis. Recently, necrostatin-1 (Nec-1), a necroptosis inhibitor, has been reported to reduce cerebral and myocardial infarction in rats or pigs. In this study, we investigated the efficacy of Nec-1 in delayed paraplegia after transient spinal cord ischemia in rabbits and assessed the expression of necroptosis- and apoptosis-related proteins in motor neurons. METHODS: This study used rabbit transient spinal cord ischemia models using a balloon catheter. They were divided into a vehicle-treated group (n = 24), Nec-1-treated group (n = 24), and sham-controls (n = 6). In the Nec-1-treated group, 1 mg/kg of Nec-1 was intravascularly administered immediately before ischemia induction. Neurological function was assessed using the modified Tarlov score, and the spinal cord was removed 8 hr and 1, 2, and 7 days after reperfusion. Morphological changes were examined using hematoxylin and eosin staining. The expression levels of necroptosis-related proteins (receptor-interacting protein kinase [RIP] 1 and 3) and apoptosis-related proteins (Bax and caspase-8) were assessed using western blotting and histochemical analysis. We also performed double-fluorescence immunohistochemical studies of RIP1, RIP3, Bax, and caspase-8. RESULTS: Neurological function significantly improved in the Nec-1-treated group compared with that in the vehicle-treated group 7 days after reperfusion (median 3 and 0, P = 0.025). Motor neurons observed 7 days after reperfusion were significantly decreased in both groups compared with the sham group (vehicle-treated, P < 0.001; Nec-1-treated, P < 0.001). However, significantly more motor neurons survived in the Nec-1-treated group than in the vehicle-treated group (P < 0.001). Western blot analysis revealed RIP1, RIP3, Bax, and caspase-8 upregulation 8 hr after reperfusion in the vehicle-treated group (RIP1, P = 0.001; RIP3, P = 0.045; Bax, P = 0.042; caspase-8, P = 0.047). In the Nec-1-treated group, the upregulation of RIP1 and RIP3 was not observed at any time point, whereas that of Bax and caspase-8 was observed 8 hr after reperfusion (Bax, P = 0.029; caspase-8, P = 0.021). Immunohistochemical study revealed the immunoreactivity of these proteins in motor neurons. Double-fluorescence immunohistochemistry revealed the induction of RIP1 and RIP3, and that of Bax and caspase-8, in the same motor neurons. CONCLUSIONS: These data suggest that Nec-1 reduces delayed motor neuron death and attenuates delayed paraplegia after transient spinal cord ischemia in rabbits by selectively inhibiting necroptosis of motor neurons with minimal effect on their apoptosis.

Risks of Mortality and Airflow Limitation in Japanese Individuals with Preserved Ratio Impaired Spirometry.

Rationale: Several Western studies have reported that participants with preserved ratio impaired spirometry (PRISm) have higher risks of airflow limitation (AFL) and death. However, evidence in East Asian populations is limited. Objectives: To investigate the relationship between PRISm and the risks of death and incident AFL in a Japanese population. Methods: A total of 3,032 community-dwelling Japanese participants aged ⩾40 years were seen in follow-up for a median of 5.3 years by annual spirometry examinations. Participants were classified into lung function categories at baseline as follows: normal spirometry (FEV1/FVC ⩾0.70 and FEV1 ⩾80% predicted), PRISm (⩾0.70 and <80%), AFL Global Initiative for Chronic Obstructive Lung Disease 1 (<0.70 and ⩾80%), and AFL Global Initiative for Chronic Obstructive Lung Disease 2-4 (<0.70 and <80%). Hazard ratios (HRs) and their 95% confidence intervals were computed using a Cox proportional hazards model. Measurements and Main Results: During the follow-up period, 131 participants died, 22 of whom died of cardiovascular disease, and 218 participants developed AFL. When examining the prognosis of each baseline lung function category, participants with PRISm had higher risks of all-cause death (HR, 2.20; 95% confidence interval, 1.35-3.59) and cardiovascular death (HR, 4.07; 1.07-15.42) than those with normal spirometry after adjusting for confounders. Moreover, the multivariable-adjusted risk of incident AFL was greater in participants with PRISm than in those with normal spirometry (HR, 2.48; 1.83-3.36). Conclusions: PRISm was associated with higher risks of all-cause and cardiovascular death and a greater risk of the development of AFL in a Japanese community.

Potential of the EVAHEART 2 Double-Cuff Tipless Inflow Cannula for Prevention of Thromboembolic Events.

A 32-year-old man, who had developed fulminant myocarditis leading to asystole, underwent implantation of an EVAHEART 2 left ventricular assist system with a double-cuff tipless inflow cannula and a concurrent Fontan operation. Approximately 2 years after the simultaneous EVAHEART 2 implantation and the Fontan operation, the patient underwent heart transplantation. There was no device-related thromboembolism or pump malfunction under adequate antithrombotic management during the postoperative support period. Computed tomography showed no malposition of the inflow cannula irrespective of the left ventricular chamber size. Macroscopically, the left ventricular cavity of the excised heart revealed a smooth inflow ostium with appropriate intimal proliferation and without pannus or wedge thrombus formation. These findings suggest the utility of the double-cuff tipless inflow cannula for long-term clinical applications, which may lead to favorable outcomes during long-term patient management. The double-cuff tipless inflow cannula, which does not protrude into the left ventricular cavity, potentially contributes to the prevention of suction events and the collision of the inflow cannula with the interventricular septum and left ventricular free wall. Further investigation is required to confirm the role of the unique EVAHEART 2 inflow cannula in reducing thromboembolic events.

Evaluation of adrenaline auto-injector prescription profiles: A population-based, retrospective cohort study within the National Insurance Claims Database of Japan.

BACKGROUND: Adrenaline is the first-line medication for managing anaphylaxis. A better understanding of prescription trends for adrenaline auto-injectors (AAIs) is important to improving patient care as well as information on health education interventions and medical guidelines. However, it has been difficult to gather comprehensive data in a sustainable manner. Thus, we aimed to investigate trends in AAI prescriptions in Japan. METHODS: We searched the National Database of Health Insurance Claims and Specific Health Checkups of Japan (NDB), a unique and comprehensive database of health insurance claims, and investigated prescriptions for AAIs for all ages (April 2017 to March 2018). We assessed the annual number of prescriptions per person as well as prescription rates per 100,000 population per year by age, sex, and geographic region. RESULTS: A total of 88,039 subjects (56,109 males, 31,930 female) and 116,758 devices (1.33 AAIs per patient per year) were prescribed AAIs at least once a year for all ages. The prescription rate for AAIs was 69.5 per 100,000 population-years. Patients aged 0-9 years were prescribed AAIs at the rate of 278.9 per 100,000 population-years. Patients aged 0-19 years were 6.4 times more likely to be prescribed AAIs than those over 20 years of age. Males were more frequently prescribed AAIs than females in all age groups, except for those aged 20-24 years. We also evaluated differences in prescription rates by geographic region. CONCLUSIONS: This comprehensive evaluation revealed trends in AAI prescriptions, thus helping develop preventive strategies with respect to anaphylaxis in Japan.