Taisuke Kojima

In Japan, “obesity” is defined as a body mass index (BMI) ≥25 kg/m2, and “severe obesity” as a BMI ≥35 kg/m2. “Obesity disease” is a pathological condition in which obesity results in or is associa...

This study aimed to estimate the medical costs attributable to obesity among Japanese adults with obesity-related health disorders using the JMDC claims database and assess the impact of body mass index (BMI) categories on the medical costs during a five-year follow-up period. A retrospective cohort study using anonymized claims and health checkup data from the JMDC database was conducted. Participants aged ≥18 years with first recorded BMI between December 2012 and December 2018 and diagnosed with obesity-related health disorders were included. Participants were stratified into two groups: those without obesity (BMI 2) and those with obesity (BMI ≥25.0 kg/m²). Annual medical costs (total, outpatient, inpatient, medication) were summarized. Generalized estimating equations (GEE) with a gamma regression model and log link function were used to estimate cost ratios and adjusted mean total medical costs, adjusting for age category, sex, baseline BMI category, and baseline outpatient visit frequency. Sensitivity analyses were performed to assess robustness across different age groups and regression models. A total of 244,150 eligible participants were analyzed (without obesity: 150,217; with obesity: 93,933). Over five-year follow-up, total medical costs per person-year increased from 218,929 to 265,919 JPY in those without obesity and from 234,093 to 323,086 JPY in those with obesity. Higher baseline BMI showed greater five-year increases in the adjusted medical costs, resulting in 27.7% increase by excess costs due to obesity with 83.3% of those attributable to BMI ≥27.0 kg/m². Sensitivity analyses confirmed the robustness of these findings. The estimated excess costs due to obesity indicate higher healthcare costs among Japanese adults with obesity-related health disorders. The per capita burden appeared higher in those with higher BMI, with most excess costs concentrated in individuals with BMI ≥27.0 kg/m². These results highlight the healthcare cost burden associated with obesity and suggest that effective weight management strategies may contribute to reducing healthcare expenditures.

Introduction The current clinical reality and burden of obesity disease in Japan are poorly understood. To address this knowledge gap, in this real-world study we describe the characteristics of Japanese individuals with obesity disease (IwOD) and their obesity disease treatments using data from the Japan Obesity Research Based on electronIc healTh record (J-ORBIT) database. Methods This retrospective observational study (January 2019 to January 2024) assessed data of ≥ 18-year-old IwOD registered in J-ORBIT and diagnosed with primary obesity per the criteria of the Japan Society for the Study of Obesity (JASSO). IwOD were grouped according to the most advanced treatment received during the study period, including the index date: lifestyle intervention, pharmacotherapy, or bariatric surgery. Demographic and clinical characteristics, degree of weight reduction, and percent change in metabolic parameters from baseline to the latest follow-up timepoint were described. Results Among the 782 IwOD included in this study, 274, 487, and 21 had received advanced treatment in the form of lifestyle intervention, pharmacotherapy, and bariatric surgery, respectively. At baseline, across treatment groups the mean age ranged from 45 to 57 years, female proportion ranged from 45% to 76%, and body mass index (BMI) ranged from 31 to 39 kg/m², respectively. Across treatment groups, 62–69% had ≥ 3 obesity-related health disorders (ORHDs) at baseline. Mean follow-up periods in these groups ranged from 846 to 1211 days. Mean weight and BMI numerically decreased from baseline to follow-up across groups. In the lifestyle intervention , pharmacotherapy, and bariatric surgery groups, 38%, 45%, and 65% of IwOD achieved ≥ 3% weight reduction at the latest follow-up timepoint. IwOD with baseline BMI ≥ 30 kg/ m² tended to achieve greater weight reduction. Triglyceride, high-density lipoprotein-cholesterol, blood glucose, hemoglobin A1c, and uric acid levels tended to improve in IwOD with ≥ 3% weight reduction and greater categories. Conclusion Obesity-associated burden in terms of ORHDs was common among Japanese IwOD. Although IwOD tended to have the highest weight reduction after bariatric surgery, this treatment is indicated for a highly restrictive population and requires specific criteria to be met, leaving many IwOD with unmet needs. These IwOD may need pharmacotherapy for better weight management than that provided by current options.

Objective: This study aimed to describe real‐world treatment patterns and clinical characteristics of Japanese patients with alopecia areata (AA), particularly focusing on those treated with baricitinib. Methods: This retrospective observational study involved patients (aged ≥ 15 years) with a confirmed diagnosis of AA between January 1, 2018, and September 30, 2023. Patient demographics, hospital characteristics, comorbidities, and treatment patterns as described in a Japanese claims database were analyzed for overall and severe AA subtypes. Baricitinib users were assessed for treatment patterns, dose modifications, persistence, and the use of combination therapies. Results: Among 81,555 patients with AA included, 421 (0.52%) received baricitinib. The mean age was 40.7 years, with a higher proportion of females (58.91%). Most AA cases were diagnosed in clinics. Severe AA patients showed similar age and gender distributions. Comorbidities such as allergic rhinitis (34.01%) and atopic dermatitis (18.69%) were more prevalent among overall AA population. Topical corticosteroids (85.78%) and oral antihistamines (78.42%) were the most commonly used treatment. Intravenous corticosteroid pulse therapy (29.98%) and baricitinib (7.55%) were more frequently adopted for patients with severe AA than in the overall AA population (2.20% and 0.52%, respectively). Baricitinib users ( n = 403) were more often diagnosed in hospitals, especially university hospitals, than in clinics. Treatment was initiated predominantly at a 4‐mg dose (84.86%). Among 403 baricitinib users, treatment persistence at 3 and 9 months was 85.70% and 70.90%, respectively; combination therapy with topical corticosteroids (43.92%) and oral antihistamines (36.97%) was the most common treatment, while 34.49% received monotherapy with baricitinib. Atopic dermatitis (64.27%) and allergic rhinitis (32.75%) were frequent comorbidities among baricitinib users. Conclusion: Topical corticosteroids remain the common treatment for AA in Japan. High treatment persistence was observed with baricitinib and was occasionally used in combination with other therapies. These findings highlight evolving treatment trends and the distinct clinical profile of patients with AA treated with baricitinib in Japan.

To describe clinical characteristics, disease burden, and treatment patterns among people with obesity disease (PwOD) in Japan, using data from the Adelphi Real World Obesity Disease Specific Programme™ (DSP). Secondary data from the Japanese DSP cohort (July to December 2022) were analyzed. PwOD had a BMI ≥25 kg/m² and ≥1 obesity-related complications (ORCs). Outcomes were summarized for all PwOD or stratified by obesity class (BMI ≥25-2 [high-degree obesity disease]) and use of anti-obesity medications (AOMs). The study included 442 PwOD (mean age: 52.8 years; 54.8% males; BMI ≥25-2: 64.5%; BMI ≥35 kg/m²: 35.5%; AOM users: n = 228; non-AOM users: n = 214). High-degree obesity disease was associated with worsened SF-36v2 scores (Physical Component Summary, Physical Functioning, Bodily Pain, and General Health), greater activity impairment, and reduced work productivity. Common weight management approaches were diet (79.9%) and exercise (51.1%). Common prescription AOMs included traditional herbal medicine (67.5%) and mazindol (21.1%). People with high-degree obesity disease (BMI ≥35 vs. ≥25-2) used more prescription AOMs (57.3 vs. 48.4%), behavioral therapy (9.6 vs. 1.8%), and weight loss surgery (2.6 vs. 0.4%). The difference in weight reduction between AOM and non-AOM users was modest. People with high-degree obesity disease experienced greater disease burden. Diet and exercise are common for weight management, while behavioral therapy is less frequently implemented. These findings highlight the challenges and unmet medical needs in treating obesity in Japan and could inform better treatment strategies in Japan and globally among the Asian population.

Simultaneous detection of multiple analytes from a single sample (multiplexing), particularly when at the point of need, can guide complex decision-making without increasing the required sample volume or cost per test. Despite recent advances, multiplexing still typically faces the critical limitation of measuring only one type of molecule per assay platform – for example, only small molecules or only nucleic acids. In this work, we address this bottleneck with a customizable platform that integrates cell-free expression (CFE) with a polymer-based aqueous two-phase system (ATPS) to produce membrane-less “protocells” containing transcription and translation machinery used for analyte detection. Multiple protocells are arrayed in microwells where each protocell droplet performs distinct reactions to detect chemically diverse targets including small molecules, minerals, and nucleic acid sequences, all from the same sample. We demonstrate that these protocell arrays can measure analytes in a human biofluid matrix, maintain function after lyophilization and rehydration, and produce visually interpretable readouts, illustrating its potential for application as a minimal-equipment, field-deployable, multi-analyte detection tool.

This work presents one-incubation one-hour multiplex ELISA enabled by aqueous two-phase systems for five-plex cytokine detection in human ThP-1 macrophages.

A new approach to generate magneto‐activatable microstructures for discrete cell adhesion to investigate cell mechanoresponsiveness is reported here. The system is based on poly(n‐butylacrylate) micropillar arrays, generated from prepolymers via C,H insertion chemistry and filled with magnetic iron oxide nanoparticles. The pillars' surfaces are modified such that only top faces of the pillars are cell attractive, while the pillar side walls and the area between the pillars are covered by a cell repelling hydrogel layer based on poly(N,N‐dimethyl acrylamide). Magnet stimulation leads to pillar deflection, which induces traction forces to adherent cells. Analysis of early mechanoresponse in human mesenchymal stem cells, specifically the localization of autophosphorylated focal adhesion kinase (pFAK Y397) and the co‐transcriptional activator yes‐associated protein (YAP), shows a clear redistribution of pFAK Y397 to the cell margins and an enhanced nuclear localization of YAP, following the magnetically induced mechanical actuation. The successful use of this technique shows that the generated magnetoactive posts are suitable tools to detect the onset (FAK) and maintenance (YAP) involved in stem cell mechanosensing and mechanotransduction. The platform combines selective cell adhesion with the possibility of magnetic actuation, thereby representing a promising technology to broaden the molecular understanding of cellular mechanobiology.

Extracellular traps (ETs), such as neutrophil extracellular traps, are a physical mesh deployed by immune cells to entrap and constrain pathogens. ETs are immunogenic structures composed of DNA, histones, and an array of variable protein and peptide components. While much attention has been paid to the multifaceted function of these structures, mechanistic studies of ETs remain challenging due to their heterogeneity and complexity. Here, a novel DNA‐histone mesostructure (DHM) formed by complexation of DNA and histones into a fibrous mesh is reported. DHMs mirror the DNA‐histone structural frame of ETs and offer a facile platform for cell culture studies. It is shown that DHMs are potent activators of dendritic cells and identify both the methylation state of DHMs and physical interaction between dendritic cells and DHMs as key tuning switches for immune stimulation. Overall, the DHM platform provides a new opportunity to study the role of ETs in immune activation and pathophysiology.