Comparison of machine-learning and logistic regression models for prediction of 30-day unplanned readmission in electronic health records: A development and validation study.

It is expected but unknown whether machine-learning models can outperform regression models, such as a logistic regression (LR) model, especially when the number and types of predictor variables increase in electronic health records (EHRs). We aimed to compare the predictive performance of gradient-boosted decision tree (GBDT), random forest (RF), deep neural network (DNN), and LR with the least absolute shrinkage and selection operator (LR-LASSO) for unplanned readmission. We used EHRs of patients discharged alive from 38 hospitals in 2015-2017 for derivation and in 2018 for validation, including basic characteristics, diagnosis, surgery, procedure, and drug codes, and blood-test results. The outcome was 30-day unplanned readmission. We created six patterns of data tables having different numbers of binary variables (that ≥5% or ≥1% of patients or ≥10 patients had) with and without blood-test results. For each pattern of data tables, we used the derivation data to establish the machine-learning and LR models, and used the validation data to evaluate the performance of each model. The incidence of outcome was 6.8% (23,108/339,513 discharges) and 6.4% (7,507/118,074 discharges) in the derivation and validation datasets, respectively. For the first data table with the smallest number of variables (102 variables that ≥5% of patients had, without blood-test results), the c-statistic was highest for GBDT (0.740), followed by RF (0.734), LR-LASSO (0.720), and DNN (0.664). For the last data table with the largest number of variables (1543 variables that ≥10 patients had, including blood-test results), the c-statistic was highest for GBDT (0.764), followed by LR-LASSO (0.755), RF (0.751), and DNN (0.720), suggesting that the difference between GBDT and LR-LASSO was small and their 95% confidence intervals overlapped. In conclusion, GBDT generally outperformed LR-LASSO to predict unplanned readmission, but the difference of c-statistic became smaller as the number of variables was increased and blood-test results were used.

Epidemiology of patients with severe asthma in Japan: a nationwide descriptive study.

Background: The 2014 European Respiratory Society/American Thoracic Society guidelines defined severe asthma based on treatment intensity and estimated the proportion of severe asthma among all asthma cases to be 5-10%. However, data supporting the estimate and comprehensive and sequential data on asthma cases are scarce. We aimed to estimate the national prevalence and proportion of severe asthma during the last decade. Methods: Using a Japanese national administrative database, which covers ≥99% of the population, we evaluated the prevalence and proportion of severe asthma in 2013, 2015, 2017 and 2019. Additionally, we elucidated the demographic characteristics, treatments and outcomes of patients with asthma. Results: The national prevalence of mild-moderate and severe asthma in 2019 was 800 and 36 per 100 000 persons, respectively. While the prevalence of mild-moderate asthma remained almost constant in the study years, the prevalence of severe asthma decreased, resulting in a reduction in the proportion of severe asthma from 5.6% to 4.3%. Although treatment modalities have evolved, such as the increased use of combination inhalers and asthma biologics, approximately 15% of mild-moderate and 45% of severe asthma cases were still considered "uncontrolled". The number of deaths from asthma decreased in patients with both mild-moderate and severe asthma. Conclusions: This study revealed that the prevalence of severe asthma in Japan decreased during the study period and fell below 5% in the most recent data. Despite treatment evolution, a substantial proportion of patients with both mild-moderate and severe asthma still have poor asthma control.

Outcomes and Baseline Predictors of Failure in Primary Standalone Xen45 Gel Stent versus Trabeculectomy for Glaucoma.

PURPOSE: To compare safety, effectiveness, and baseline predictors of failure in standalone primary Xen45 gel stent (Xen) versus trabeculectomy (Trab) in glaucoma. DESIGN: Retrospective study. SUBJECTS: Subjects that underwent primary Xen or Trab augmented by mitomycin-C with at least 12 months follow-up. METHODS: Multinational observational study of eyes in the Fight Glaucoma Blindness international registry MAIN OUTCOME MEASURES: The primary outcome was success at 12 months defined by intraocular pressure (IOP) reduction ≥ 20% from baseline and ≤ threshold IOPs of 15, 18, and 21 mmHg with (qualified) or without (complete) medications and without secondary glaucoma surgery. Multivariable mixed effects Cox regression models were used to identify risk factors for failure in each cohort. RESULTS: A total of 701 eyes (Xen, 308; Trab, 393) of 596 subjects were included with baseline IOP being significantly higher (22.4 vs. 19.9 mmHg, P < 0.001) and baseline medications significantly lower in the Xen versus the Trab group (2.9 vs. 3.4, P < 0.001). Baseline visual field mean deviation was less severe in the Xen group (-9.47 vs. -13.04 dB, P < 0.001). The proportion of complete surgical success was significantly lower in the Xen versus Trab group across the 3 upper IOP limits at 12 months; 32% versus 52% at 15 mmHg, 37% versus 54% at 18 mmHg, and 39% versus 55% at 21 mmHg (P < 0.001). The incidence of postoperative numerical and symptomatic hypotony was lower in the Xen versus Trab group. In the Xen cohort, a higher failure rate was associated with Asian ethnicity (hazard ratio [HR], 1.97; 95% confidence interval (CI), 1.03-3.79) and use of oral acetazolamide at baseline (HR, 1.74; 95% CI, 1.13-2.70), whereas a lower failure rate was associated with diagnosis of ocular hypertension/open-angle glaucoma suspect (HR, 0.40; 95% CI, 0.20-0.82) and secondary open-angle glaucoma (HR, 0.46; 95% CI, 0.26-0.82). Exposure to prostaglandin analog was associated with greater failure in the Trab group (HR, 2.66; 95% CI, 1.18-6.01). CONCLUSIONS: There was significantly greater complete success at 12 months across all complete success definitions for Trab compared with Xen, whereas the rate of postoperative hypotony was significantly lower in the Xen group. Asian ethnicity and use of oral acetazolamide at baseline were associated with greater failure in Xen, whereas exposure to prostaglandin analog was associated with greater failure in Trab patients. Such baseline predictors of success and failure may help guide patient selection for subconjunctival minimally invasive glaucoma surgery in patients undergoing surgical intervention. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Two-year outcomes of Xen 45 gel stent implantation in patients with open-angle glaucoma: real-world data from the Fight Glaucoma Blindness registry.

OBJECTIVE: To evaluate efficacy and safety outcomes of the Xen 45 gel stent implant over 24 months of follow-up. METHODS: A retrospective analysis of prospectively collected data from the Fight Glaucoma Blindness observational registry. Complete success (CS) was defined as intraocular pressure (IOP) reduction ≥20% from preoperative and an IOP ≤18 mm Hg and ≥6 mm Hg with no secondary procedure at 2 years and without IOP-lowering medications. Qualified success (QS) was defined similarly, allowing the use of IOP-lowering medications. RESULTS: The Xen 45 gel stent implant was implanted in 646 eyes of 515 patients. Preoperative IOP was 21.4±7.6 (mean±SD) mm Hg on 2.7±1.3 IOP-lowering medication and mean deviation was -10.2±8.4 dB. After 24-month follow-up, IOP was 16.8±7.3 mm Hg (mean reduction of 21.7%) on 1.2±1.4 IOP-lowering medications. CS and QS rates at 24 months were 26% and 48%, respectively. CS and QS were higher in the Xen stand-alone group (33% and 52%, respectively) than in the Xen+cataract group (16% and 42%, respectively). Bleb needling was performed in 28.4% of cases, and 18% underwent a secondary procedure. CONCLUSIONS: The Xen 45 gel stent implant offers acceptable long-term efficacy for the treatment of open-angle glaucoma. However, there is a significant rate of reoperation and needling, and outcomes are less effective if combined with cataract surgery.

Association of Novel Antihyperglycemic Drugs Versus Metformin With a Decrease in Asthma Exacerbations.

BACKGROUND: Similar to metformin, dipeptidyl peptidase-4 inhibitors (DPP-4 Is), glucagon-like peptidase 1 receptor agonists (GLP-1 RAs), and sodium glucose co-transporter-2 inhibitors (SGLT-2 Is) may improve control of asthma owing to their multiple potential mechanisms, including differential improvements in glycemic control, direct anti-inflammatory effects, and systemic changes in metabolism. OBJECTIVE: To investigate whether these novel antihyperglycemic drugs were associated with fewer asthma exacerbations compared with metformin in patients with asthma comorbid with type 2 diabetes. METHODS: Using a Japanese national administrative database, we constructed 3 active comparators-new user cohorts of 137,173 patients with a history of asthma starting the novel antihyperglycemic drugs and metformin between 2014 and 2022. Patient characteristics were balanced using overlap propensity score weighting. The primary outcome was the first exacerbation requiring systemic corticosteroids, and the secondary outcomes included the number of exacerbations requiring systemic corticosteroids. RESULTS: DPP-4 Is and GLP-1 RAs were associated with a higher incidence of exacerbations requiring systemic corticosteroids compared with metformin (DPP-4 Is: 18.2 vs 17.4 per 100 person-years, hazard ratio: 1.09, 95% confidence interval [CI]: 1.05-1.14; GLP-1 RAs: 24.9 vs 19.0 per 100 person-years, hazard ratio: 1.14, 95% CI: 1.01-1.28). In contrast, the incidence of exacerbations requiring systemic corticosteroids was similar between the SGLT-2 Is and metformin groups (17.3 vs 18.1 per 100 person-years, hazard ratio: 1.00, 95% CI: 0.97-1.03). While DPP-4 Is and GLP-1 RAs were associated with more exacerbations requiring systemic corticosteroids, SGLT-2 Is were associated with slightly fewer exacerbations requiring systemic corticosteroids (53.7 vs 56.6 per 100 person-years, rate ratio: 0.95, 95% CI: 0.91-0.99). CONCLUSIONS: While DPP-4 Is and GLP-1 RAs were associated with poorer control of asthma compared with metformin, SGLT-2 Is offered asthma control comparable to that of metformin.

One-Year Anti-VEGF Therapy Outcomes in Diabetic Macular Edema Based on Treatment Intensity: Data from the Fight Retinal Blindness! Registry.

PURPOSE: To compare 1-year outcomes of eyes with diabetic macular edema (DME) treated in routine clinical practice based on the proportion of visits where intravitreal VEGF inhibitor injections were delivered. DESIGN: Cohort study. PARTICIPANTS: There were 2288 treatment-naive eyes with DME starting intravitreal VEGF inhibitor therapy from October 31, 2015 to October 31, 2021 from the Fight Retinal Blindness! international outcomes registry. METHODS: Eyes were grouped according to the proportion of visits at which an injection was received, Group A with less than the median of 67% (n = 1172) versus Group B with greater than the median (n = 1116). MAIN OUTCOME MEASURES: Mean visual acuity (VA) change after 12 months of treatment. RESULTS: The mean (95% confidence interval [CI]) VA change after 12 months of treatment was 3.6 (2.8-4.4) letters for eyes in Group A versus 5.2 (4.4-5.9) letters for eyes in Group B (P = 0.005). The mean (95% CI) central subfield thickness (CST) change was -69 (-76 to -61) µm and -85 (-92 to -78) µm for eyes in Group A versus Group B, respectively (P = 0.002). A moderate positive correlation was observed between the number of injections received over 12 months of treatment and the change in VA (P < 0.001). Additionally, eyes that received more injections had a moderately greater CST reduction. CONCLUSIONS: This registry analysis found that overall VA and anatomic outcomes tended to be better in DME eyes treated at a greater proportion of visits in the first year of intravitreal VEGF inhibitor therapy. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Noninvasive Positive Airway Pressure Management for Post-extubation Support in Preterm Infants: Observational Cohort Study with Overlap Weighting Analysis.

BACKGROUND: Nasal continuous positive airway pressure (NCPAP), nasal intermittent positive pressure ventilation (NIPPV), and high-flow nasal cannula (HFNC) are often used after initial extubation in preterm infants. However, data regarding the choice between NCPAP/NIPPV and HFNC are limited. This study examined which therapy was more effective as post-extubation support. METHODS: This is a retrospective, cohort study that used the Diagnosis Procedure Combination database in Japan, 2011-2021. Propensity score overlap weighting analyses were performed to compare the composite outcomes of in-hospital death and reintubation in preterm infants who received NCPAP/NIPPV and HFNC. We identified infants born at gestational age 22-36 weeks who were intubated within 1 day of birth. We included patients who underwent NCPAP/NIPPV or HFNC after initial extubation. Patients with airway obstruction or congenital airway abnormalities were excluded. RESULTS: We identified 1,203 preterm infants treated with NCPAP/NIPPV (n = 525) or HFNC (n = 678). The median (interquartile range) gestational age at delivery was 30 (27-33) weeks, and birth weight was 1296 (884-1,802) g. Compared with the HFNC group, the NCPAP/NIPPV group had a significantly lower proportion of the composite outcome after the overlap weighting analysis (risk ratio, 0.62; 95% confidence interval, 0.47 to 0.83; p = 0.001). This significant difference was also observed in infants born at gestational age 22-31 weeks, whereas no significant difference was observed in infants born at gestational age 32-36 weeks. CONCLUSIONS: NCPAP/NIPPV may be a superior post-extubation support than HFNC in preterm infants, especially in those born at gestational age of 22-31 weeks.

Impact of COVID-19 pandemic on the number of otolaryngologic surgeries in Japan.

OBJECTIVE: Previous studies show that the COVID-19 pandemic affected the number of surgeries performed. However, data on the association between the COVID-19 pandemic and otolaryngologic surgeries according to subspecialties are lacking. This study was performed to evaluate the impact of the COVID-19 pandemic on various types of otolaryngologic surgeries. METHODS: We retrospectively identified patients who underwent otolaryngologic surgeries from April 2018 to February 2021 using a Japanese national inpatient database. We performed interrupted time-series analyses before and after April 2020 to evaluate the number of otolaryngologic surgeries performed. The Japanese government declared its first state of emergency during the COVID-19 pandemic in April 2020. RESULTS: We obtained data on 348,351 otolaryngologic surgeries. Interrupted time-series analysis showed a significant decrease in the number of overall otolaryngologic surgeries in April 2020 (-3619 surgeries per month; 95% confidence interval, -5555 to -1683; p < 0.001). Removal of foreign bodies and head and neck cancer surgery were not affected by the COVID-19 pandemic. In the post-COVID-19 period, the number of otolaryngologic surgeries, except for ear and upper airway surgeries, increased significantly. The number of tracheostomies and peritonsillar abscess incisions did not significantly decrease during the COVID-19 pandemic. CONCLUSION: The COVID-19 pandemic was associated with a decrease in the overall number of otolaryngologic surgeries, but the trend differed among subspecialties.

Epidemiology of patients with lymphangioleiomyomatosis: A descriptive study using the national database of health insurance claims and specific health checkups of Japan.

BACKGROUND: Using patient registries or limited regional hospitalization data may result in underestimation of the incidence and prevalence of rare diseases. Therefore, we used the national administrative database to estimate the incidence and prevalence of lymphangioleiomyomatosis over six years (2014-2019) and describe changes in clinical practice and mortality. METHODS: We extracted data from the National Database of Health Insurance Claims and Specific Health Checkups of Japan between January 2013 and December 2020. This database covers ≥99% of the population. We used the diagnostic code for lymphangioleiomyomatosis to estimate the incidence and prevalence from 2014 to 2019. Additionally, we examined the demographic characteristics, treatments, comorbidities, and mortality of the patients. RESULTS: In women, the incidence and prevalence of lymphangioleiomyomatosis in 2019 were approximately 3 per 1,000,000 person-years and 28.7 per 1,000,000 persons, respectively. While, in men, the incidence and prevalence of lymphangioleiomyomatosis were <0.2 per 1,000,000 person-years and 0.8 per 1,000,000 persons, respectively. From 2014 to 2019, the proportion of prescriptions of sirolimus and everolimus increased, while the use of home oxygen therapy, chest drainage, comorbid pneumothorax, and bloody phlegm decreased. The mortality rate remained stable at approximately 1%. CONCLUSIONS: The incidence and prevalence of lymphangioleiomyomatosis were higher in women than those reported previously. Although the incidence did not change during the 6-year period, the prevalence gradually increased. Moreover, lymphangioleiomyomatosis was observed to be rare in men. The practice of treating patients with lymphangioleiomyomatosis changed across the six years while mortality remained low, at approximately 1%.

Clinical Features and Outcomes of Shoshin Beriberi.

Shoshin beriberi is a fulminant form of wet beriberi, but there are no large-scale studies detailing the clinical features of this disease. We investigated the clinical features and outcomes of Shoshin beriberi using data from a nationwide database in Japan.Using the Diagnosis Procedure Combination database, we identified patients with Shoshin beriberi between July 2010 and March 2021. We retrospectively investigated the characteristics, comorbidities, treatment, and in-hospital mortality of patients with Shoshin beriberi. The chi-square test or Fisher's exact test was used for categorical variables, and the Mann-Whitney U-test was used for continuous variables.We identified 62 patients with Shoshin beriberi. The median (interquartile range) age was 63 (48-69) years. Furthermore, 54 patients were male (87%). The most common comorbidity was alcohol-related disorder (34%). The median (interquartile range) length of hospital and intensive care unit stays were 17 (range, 10-35) and 5 (range, 1-9) days, respectively. The proportion of patients who received venoarterial extracorporeal membrane oxygenation, intra-aortic balloon pump, continuous renal replacement therapy, and mechanical ventilation was 11, 5, 29, and 63%, respectively. Among the patients with Shoshin beriberi, 53% received 2 or more catecholamines or inotropes. The in-hospital mortality was 23%. Impaired consciousness at admission was significantly related to in-hospital death (P < 0.001).The present study is the first and largest to describe the clinical features of patients with Shoshin beriberi using a nationwide database. Impaired consciousness at admission was significantly associated with in-hospital death.

Exploring the influence of a financial incentive scheme on early mobilization and rehabilitation in ICU patients: an interrupted time-series analysis.

BACKGROUND: Clinical guidelines recommend early mobilization and rehabilitation (EMR) for patients who are critically ill. However, various barriers impede its implementation in real-world clinical settings. In 2018, the Japanese universal healthcare coverage system announced a unique financial incentive scheme to facilitate EMR for patients in intensive care units (ICU). This study evaluated whether such an incentive improved patients' activities of daily living (ADL) and reduced their hospital length of stay (LOS). METHODS: Using the national inpatient database in Japan, we identified patients admitted to the ICU, who stayed over 48 hours between April 2017 and March 2019. The financial incentive required medical institutions to form a multidisciplinary team approach for EMR, development and periodic review of the standardized rehabilitation protocol, starting rehabilitation within 2 days of ICU admission. The incentive amounted to 34.6 United States Dollars per patient per day with limit 14 days, structured as a per diem payment. Hospitals were not mandated to provide detailed information on individual rehabilitation for government, and the insurer made payments directly to the hospitals based on their claims. Exposure was the introduction of the financial incentive defined as the first day of claim by each hospital. We conducted an interrupted time-series analysis to assess the impact of the financial incentive scheme. Multivariable radon-effects regression and Tobit regression analysis were performed with random intercept for the hospital of admission. RESULTS: A total of 33,568 patients were deemed eligible. We confirmed that the basic assumption of ITS was fulfilled. The financial incentive was associated with an improvement in the Barthel index at discharge (0.44 points change in trend per month; 95% confidence interval = 0.20-0.68) and shorter hospital LOS (- 0.66 days change in trend per month; 95% confidence interval = - 0.88 - -0.44). The sensitivity and subgroup analyses showed consistent results. CONCLUSIONS: The study suggests a potential association between the financial incentive for EMR in ICU patients and improved outcomes. This incentive scheme may provide a unique solution to EMR barrier in practice, however, caution is warranted in interpreting these findings due to recent changes in ICU care practices.

Treatments and outcomes of neonatal disseminated intravascular coagulation with and without neonatal asphyxia: A retrospective study using nationwide data in Japan.

BACKGROUND: Although neonatal disseminated intravascular coagulation (DIC) is associated with high mortality and severe complications, few studies have reported its clinical course. We aimed to describe the characteristics, treatments, and outcomes of neonatal DIC by using a national inpatient database. METHODS: Using the Japanese Diagnosis Procedure Combination database, we identified 5533 patients with neonatal DIC who were admitted to neonatal intensive care units between July 2010 and March 2020. We categorized the patients into those with asphyxia (n = 2911) and those without asphyxia (n = 2622). We investigated the patient characteristics, treatments, and outcomes. We further categorized neonates with asphyxia according to its severity. RESULTS: The gestational age of neonates with asphyxia was significantly lower than that of neonates without asphyxia (P < 0.001). Antithrombin was most commonly used for DIC (40%). Neonates with asphyxia were more likely to receive antithrombin (43% vs. 38%; P < 0.001), recombinant human soluble thrombomodulin (28% vs. 20%; P < 0.001), and fresh frozen plasma transfusion (68% vs. 51%; P < 0.001) than those without asphyxia. Neonates with asphyxia had higher in-hospital mortality (17% vs. 10%; P < 0.001), severe bleeding (11% vs. 6.8%; P < 0.001), and hospitalization costs than those without asphyxia. Additionally, neonates with severe asphyxia were more likely to receive several DIC therapies (such as recombinant human soluble thrombomodulin [30% vs. 24%]) and had higher in-hospital mortality (19% vs. 11%) and hospitalization costs than those with mild asphyxia. CONCLUSIONS: In this large retrospective study of neonatal DIC, patients with asphyxia received several treatments and demonstrated unfavorable outcomes when compared to those without asphyxia.

Cost-effectiveness analysis of prophylactic laser peripheral iridotomy for primary angle-closure suspect in Japan.

BACKGROUND/OBJECTIVES: This study aimed to compare the cost-effectiveness of prophylactic laser peripheral iridotomy (LPI) with that of observation for primary angle-closure suspect (PACS) in Japan. SUBJECTS/METHODS: A Markov model was developed to compare the costs and utilities of prophylactic LPI with those of observation of 40-year-old patients with PACS. In the model with a yearly cycle over a 20-year time horizon, the disease was postulated to irreversibly progress from PACS to primary angle closure, followed by primary angle-closure glaucoma, unilateral blindness, and bilateral blindness. The parameters were estimated mainly based on a recent randomised controlled trial and analyses of Japanese claims data. The incremental cost-effectiveness ratio was estimated from the healthcare payer's perspective and evaluated at the willingness-to-pay 5 million Japanese Yen per quality-adjusted life-year. The observation period and the age at entry into the cohort was changed to account for a variety of clinical courses in sensitivity analyses. We conducted one-way deterministic sensitivity analysis and probabilistic sensitivity analysis with Monte Carlo simulations with 10 000 iterations. RESULTS: The incremental cost-effectiveness ratio of LPI was 2,287,662 Japanese Yen (14,298 pounds sterling) per quality-adjusted life-year, which was below the willingness-to-pay threshold. The ratios were approximately 4 and 8 million in the 15-year and 10-year time horizons, respectively. Increasing the age at entry had little influence on the incremental cost-effectiveness ratio. The deterministic and probabilistic sensitivity analyses indicated that the results were robust. CONCLUSIONS: Our results indicate that prophylactic LPI for middle-aged patients with PACS is cost-effective in Japan.

RECENT TRENDS IN THE CUMULATIVE INCIDENCE AND INTERVENTION PATTERNS OF RETINOPATHY OF PREMATURITY IN JAPAN: A Multicenter Analysis, 2011-2020.

PURPOSE: To investigate recent trends in the cumulative incidence and treatment patterns of retinopathy of prematurity (ROP) in Japan. METHODS: A retrospective multicenter cohort was conducted from 2011 to 2020 using the Diagnosis Procedure Combination inpatient database. Preterm newborns with birth weight <2,500 g were categorized by birth weight. The cumulative incidence of ROP, treatment patterns, and association between treatment and birth weight were investigated. RESULTS: A total of 82,683 preterm infants were identified, of whom 9,335 (11.3%) were diagnosed with ROP. The cumulative incidence of ROP increased by 15% in those with birth weight <500 g over the study period. Among the ROP infants, 20.2% received treatment, including laser photocoagulation (94.8%), intravitreal injection (3.8%), or both (1.8%). The proportion receiving laser photocoagulation decreased followed by an increase in intravitreal injection. This shift in intervention pattern was most conspicuous for those with birth weight 750 to 1,249 g. The risk ratio of receiving laser and intravitreal injection for those weighing <500 g was 24.7 (95% confidence interval, 10.5-58.2) and 28.4 (5.8-138.1), respectively, as compared with infants weighing >1,500 g. CONCLUSION: The cumulative incidence of ROP increased in infants with birth weight <500 g. A shift from laser photocoagulation to intravitreal injection was observed in the more recent years.

Association between body mass index and outcomes after autologous breast reconstruction: a nationwide inpatient database study in Japan.

BACKGROUND: Although autologous reconstruction following breast cancer surgery is common, little is known about the association between preoperative body mass index (BMI) and short-term surgical outcomes. This study investigated the association between BMI and short-term surgical outcomes in autologous breast reconstruction using a nationwide Japanese inpatient database. METHODS: We retrospectively identified female patients with breast cancer who underwent breast reconstruction using a pedicled flap or free flap from July 2010 to March 2020. Multivariable regression analyses and restricted cubic spline analyses were conducted to investigate the associations between BMI and short-term outcomes with adjustment for demographic and clinical backgrounds. RESULTS: Of the 13,734 eligible patients, 7.1% and 22.2% had a BMI of < 18.5 kg/m2 and > 25 kg/m2, respectively. Compared with BMI of 18.5-21.9 kg/m2, overweight (25.0-29.9 kg/m2) and obese (≥ 30.0 kg/m2) were significantly associated with higher occurrences of takebacks (odds ratio, 1.74 [95% confidence interval, 1.28-2.38] and 2.89 [1.88-4.43], respectively) and overall complications (1.37 [1.20-1.57] and 1.77 [1.42-2.20], respectively). In the restricted cubic spline analyses, BMI showed J-shaped associations with takebacks, overall complications, local complications, and wound dehiscence. BMI also demonstrated linear associations with postoperative surgical site infection, duration of anesthesia, duration of drainage, length of stay, and hospitalization costs. CONCLUSION: In autologous breast reconstruction following breast cancer surgery, a higher BMI was associated with takebacks, morbidity, a longer hospital stay, and higher total costs, whereas a lower BMI was associated with fewer surgical site infections, a shorter hospital stay, and lower total costs.

Treatment courses and outcomes of oesophageal atresia in patients with trisomy 18: a case series of 271 patients from a nationwide database in Japan.

OBJECTIVE: To describe characteristics, treatments and clinical outcomes of patients with trisomy 18 and oesophageal atresia, using a nationwide database in Japan. DESIGN: Descriptive study using a retrospective cohort. SETTING: A nationwide inpatient database including 90% of hospitals with neonatal intensive care units in Japan. PATIENTS: Patients hospitalised within a day after birth for both oesophageal atresia and trisomy 18 between July 2010 and March 2020. INTERVENTIONS: Radical surgery for oesophageal atresia. MAIN OUTCOME MEASURES: Characteristics, treatment course and outcomes. RESULTS: Among 271 patients with both oesophageal atresia and trisomy 18, 70 patients underwent radical surgery for oesophageal atresia. Patients who underwent radical surgery were less likely to have severe cardiac anomalies (17% vs 32%; p=0.020), but more likely to undergo cardiac surgery (21% vs 9.5%; p=0.012) than those who did not. The overall in-hospital mortality was lower (54% vs 79%; p<0.001) and the median age at death was higher (210 days vs 39 days; p<0.001) in patients who underwent radical surgery than the others. Postoperative mortality within 30 days after radical surgery was 5.7%. Patients who underwent radical surgery were likely to be discharged to home (50% vs 18%; p<0.001), whereas the age at home discharge (median 314 days vs 216 days; p=0.19) and the requirement for each home treatment did not differ significantly by radical surgery. CONCLUSION: This study provides information that will aid the clinical decision-making process for patients with oesophageal atresia and trisomy 18. Radical surgery may be a safe and feasible treatment option.

Association between aspirin dose and outcomes in patients with acute Kawasaki disease: a nationwide retrospective cohort study in Japan.

This study aimed to identify the appropriate dose of aspirin to be prescribed to patients with acute Kawasaki disease (KD). Using a Japanese national inpatient database, we identified patients with KD treated with intravenous immunoglobulin between 2010 and 2021.The outcomes included the occurrence of coronary artery abnormalities and intravenous immunoglobulin resistance, length of hospital stay, and medical costs. Restricted cubic spline functions were performed to examine the association between aspirin dose and the outcomes. Data of 82,109 patients were extracted from the database. Non-linear associations were observed between aspirin dose and the outcomes. In comparison with an aspirin dose of 30 mg/kg/day, the odds ratio (95% confidence interval) for coronary artery abnormalities was 1.40 (1.13-1.75) at 5 mg/kg/day. An aspirin dose of ≥ 30 mg/kg/day did not significantly change the odds ratio for coronary artery abnormalities. Intravenous immunoglobulin resistance was significantly lower at a dose of 60 mg/kg/day or higher. CONCLUSION:  The results showed no significant association between aspirin escalation over standard-dose and coronary artery abnormalities in patients with acute KD. High-dose aspirin showed the potential to reduce hospital stay and medical costs without increasing complications. WHAT IS KNOWN: • Aspirin is used as a standard treatment together with intravenous immunoglobulin for acute Kawasaki disease (KD). However, few studies have shown the most effective dosage of aspirin to prevent coronary artery abnormalities (CAAs). WHAT IS NEW: • There was no significant association between aspirin dose escalation and CAAs in patients with acute KD.

Ocular Adverse Events After Influenza Vaccination in Older Adults: Self-Controlled Case Series Using a Large Database in Japan.

BACKGROUND: To clarify the risk of adverse ocular events following influenza vaccination. METHODS: This self-controlled case series study used a claims database linked to vaccination records of a large city in Japan between April 2014 and September 2021. Individuals aged ≥ 65 years who developed adverse ocular events during the follow-up period were included. The exposure was influenza vaccination. The primary outcome was defined as the occurrence of at least one of the following five eye diseases: uveitis, scleritis, retinal vein occlusion, retinal artery occlusion, or optic neuritis. Conditional Poisson regression was used to estimate the within-subject incidence rate ratio of ocular adverse events during the risk period (0-56 days after vaccination) compared to the control period. RESULTS: A total of 4,527 cases were eligible for the study (median age, 74 years; male, 42%). The incidence rate ratio for the outcome during the risk period was 0.99 (95% confidence interval, 0.87 to 1.14). No increased risk was observed for individual components of the outcome either; the incidence rate ratio was 0.94 (0.78 to 1.13) for uveitis, 1.17 (0.86 to 1.59) for scleritis, 0.98 (0.76 to 1.27) for retinal vein occlusion, 0.89 (0.42 to 1.87) for retinal artery occlusion, and 0.87 (0.44 to 1.70) for optic neuritis. CONCLUSIONS: This self-controlled case series showed no apparent increase in the risk of adverse ocular events after influenza vaccination among older adults. These results mitigate the concerns of older adults who may hesitate to receive influenza vaccination for fear of adverse ocular events. ABBREVIATION: HR = hazard ratio; CI = confidence interval; RVO = retinal vein occlusion; SCCS = self-controlled case series.

Hospital volume and outcomes following bronchoscopy in patients with interstitial lung disease: A retrospective observational study using a national inpatient database in Japan.

BACKGROUND: Interstitial lung diseases (ILDs) are a group of diffuse parenchymal lung disorders that cause inflammation and fibrosis in the interstitium of the lungs. Histopathological examination is pivotal to accurately diagnose the type of ILD, and bronchoscopy (BS) is often performed to collect lung tissue. This study aimed to determine the relationship between hospital volume and outcomes following BS in patients with ILD. METHODS: Inpatient data on patients with ILD who underwent BS between July 1, 2010 and March 31, 2021 were extracted from the Japanese Diagnosis Procedure Combination database. The annual hospital volume of BS was categorized into four (very low- [≤15 cases/year], low- [16-29 cases/year], high- [30-54 cases/year], and very high- [≥55 cases/year] volume) groups. The primary outcome was all-cause 14-day mortality after BS. Multiple imputation methods followed by multivariable logistic regression analyses fitted with generalized estimating equations were used to estimate the association between hospital volume and 14-day mortality after BS. RESULTS: A total of 89,454 patients with ILD from 1002 hospitals underwent BS. The all-cause mortality within 14 days after BS was 0.77%. An inverse trend was observed between mortality and hospital volume. Compared with the very low-hospital volume group, the very high-hospital volume group was significantly associated with a lower mortality (adjusted odds ratio = 0.63, 95% confidence interval: 0.48-0.85, p = 0.002). CONCLUSIONS: Hospital volume was inversely associated with all-cause mortality within 14 days after BS for hospitalized patients with ILD.