Sapporo City Research Articles

Prediction of the future number of fall-related emergency medical services calls in older individuals

BackgroundFalls among older individuals contribute significantly to the rise in ambulance transport use. To recognize the importance of future countermeasures, we estimated the projected number and percentage of fall-related emergency medical service (EMS) calls.MethodsWe examined the sex, age group, and location of falls among patients aged ≥ 65 years who contacted emergency services in Sapporo City from 2013 to 2021. Annual fall-related calls per population subgroup were calculated, and trends were analyzed. Four models were used to estimate the future number of fall-related calls from the 2025–2060 projected population: (1) based on the 2022 data, estimates from the 2013–2022 data using (2) Poisson progression, (3) neural network, (4) estimates from the 2013–2019 data using neural network. The number of all EMS calls was also determined using the same method to obtain the ratio of all EMS calls.ResultsDuring 2013–2022, 70,262 fall-related calls were made for those aged ≥ 65 years. The rate was higher indoors among females and outdoor among males in most age groups and generally increased with age. After adjusting for age, the rate increased by year. Future estimates of the number of fall calls are approximately double the number in 2022 in 2040 and three times in 2060, with falls accounting for approximately 11% and 13% of all EMS calls in 2040 and 2060, respectively.ConclusionThe number of fall-related EMS calls among older people is expected to increase in the future, and the percentage of EMS calls will also increase; therefore, countermeasures are urgently needed.

A novel oscillatory thermal response test method for efficient characterization of ground thermal properties: Methodology and data analysis

This study presents a novel thermal response testing (TRT) approach to minimize test duration, labor, and associated costs. The proposed method, Oscillatory Thermal Response Test (OTRT), employs an oscillating heat flux using a sinusoidal wave with specific frequency and amplitude characteristics. A custom-designed TRT apparatus was developed to regulate the heating injection pattern for precise control. In Sapporo City, Hokkaido Prefecture, and Kai City, Yamanashi Prefecture, Japan, two in-situ OTRTs were conducted. The temperature profiles of the fluid and undisturbed soil were measured through optical fiber cables integrated within the U-tube legs. A novel analytical method was devised to filter, smooth, and fit the recorded data, enabling the determination of the response temperature amplitudes at the borehole inlet and outlet. Also, the temperature time derivative method calculates the effective thermal conductivity in the early 3 h. Comparative analysis with Normal Thermal Response Tests (NTRTs) demonstrated the accuracy and validity of the OTRT approach. Significant conclusions from this study include a remarkable reduction in TRT duration by over 95 %, with a high accuracy of 92 % achieved using only the first 3 h of testing. The proposed method exhibited a Root Mean Square Error (RMSE) of 0.1 W/(m·K) compared to NTRTs. To establish a strong correlation between the Amplitude Ratio and Effective Thermal Conductivity, further experimental studies are essential to address the limitations of the current study. These studies should explore a variety of geological and hydrological conditions, borehole diameters, type of heat exchanger, diameter of U-tubem grouting material, combined with numerical analysis, to enhance our understanding of this relationship.

The case of Mediterranean spotted fever of the traveler returned from Zambia

We report the case of a traveler who returned from Zambia and was diagnosed with Mediterranean spotted fever (MSF), an infectious disease caused by Rickettsia conorii conorii. The patient presented to Sapporo City General Hospital with symptoms of fever, malaise, headache, and rash. The pathogen was identified by Polymerase Chain Reaction assays and subsequent analyses. The patient improved with 10-day treatment of oral doxycycline. Although some cases of MSF have been reported in sub-Saharan Africa, none have been reported in Zambia. Rhipicephalus sanguineus sensu lato, the vector of the Rickettsia conorii conorii, has been found in various areas of Zambia. Our case report highlights the potential threat of Mediterranean spotted fever in urban areas of Zambia.

Patient Characteristics and Public Health Office Factors Associated With Long Reporting Delay of COVID-19 Cases in Sapporo City, Japan.

For therapeutic efficacy, molnupiravir and nirmatrelvir-ritonavir must be started to treat patients within 5 days of disease onset to treat patients with novel coronavirus disease 2019 (COVID-19). However, some patients spend more than 5 days from disease onset before reporting to the Public Health Office. This study aimed to clarify the characteristics of patients with reporting delay. This study included data from 12,399 patients with COVID-19 who reported to the Public Health Office from March 3rd, 2021 to June 30th, 2021. Patients were stratified into "linked" (n = 7,814) and "unlinked" (n = 4,585) cases depending on whether they were linked to other patients. A long reporting delay was defined as the difference between the onset and reporting dates of 5 days or more. Univariate and multivariate analyses were performed using log-binomial regression to identify factors related to long reporting delay, and prevalence ratios with corresponding 95% confidence intervals were calculated. The proportion of long reporting delay was 24.4% (1,904/7,814) and 29.3% (1,344/4,585) in linked and unlinked cases, respectively. Risks of long reporting delay among linked cases were living alone and onset on the day with a higher 7-day daily average confirmed cases or onset on weekends; whereas, risks for unlinked cases were age over 65 years, without occupation, and living alone. Our results suggest the necessity to establish a Public Health Office system that is less susceptible to the rapid increase in the number of patients, promotes educational activities for people with fewer social connections, and improves access to health care.

The Association between COVID-19-Related Discrimination and Probable Post-Traumatic Stress Disorder among Patients with COVID-19 in Sapporo, Japan.

BackgroundDisasters such as earthquakes, terrorism, and pandemics have triggered post-traumatic stress disorder (PTSD), and discrimination against the affected individuals has been linked to the development of PTSD. However, there is limited evidence regarding the association between discrimination against coronavirus disease 2019 (COVID-19) patients and probable PTSD in Japan.MethodsWe conducted a cross-sectional study utilizing a web-based questionnaire targeting individuals who had contracted the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in Sapporo City. A total of 4247 individuals with laboratory-confirmed SARS-CoV-2 infection spanning from February 2020 to February 2022 completed the questionnaire (response rate: 15.9%). Probable PTSD was measured using the three-item Posttraumatic Diagnostic Scale. The stratified exact logistic regression was applied to calculate the odds ratios (OR) of probable PTSD for COVID-19-related discrimination with adjusted factors.ResultsThis study included 3626 patients who had a history of SARS-CoV-2 infection. Among them, 321 patients (8.9%) experienced COVID-19-related discrimination. The prevalence of probable PTSD was 19.6% (63/321) among the patients who experienced COVID-19-related discrimination, and 4.6% (152/3305) among those who had not encountered such discrimination. The adjusted OR of COVID-19-related discrimination for probable PTSD was 4.68 (95% confidence interval [95% CI], 3.36-6.53). The population attributable fraction of probable PTSD attributable to COVID-19-related discrimination among COVID-19 patients was estimated to be 23.4% (95% CI, 21.5-25.3).ConclusionThe comprehensive epidemiological survey of COVID-19 patients in Japan showed that COVID-19-related discrimination was associated with a higher prevalence of probable PTSD. Mitigating discrimination could be helpful to attenuate PTSD in future pandemics.

Zero-Shot Traffic Sign Recognition Based on Midlevel Feature Matching

Traffic sign recognition is a complex and challenging yet popular problem that can assist drivers on the road and reduce traffic accidents. Most existing methods for traffic sign recognition use convolutional neural networks (CNNs) and can achieve high recognition accuracy. However, these methods first require a large number of carefully crafted traffic sign datasets for the training process. Moreover, since traffic signs differ in each country and there is a variety of traffic signs, these methods need to be fine-tuned when recognizing new traffic sign categories. To address these issues, we propose a traffic sign matching method for zero-shot recognition. Our proposed method can perform traffic sign recognition without training data by directly matching the similarity of target and template traffic sign images. Our method uses the midlevel features of CNNs to obtain robust feature representations of traffic signs without additional training or fine-tuning. We discovered that midlevel features improve the accuracy of zero-shot traffic sign recognition. The proposed method achieves promising recognition results on the German Traffic Sign Recognition Benchmark open dataset and a real-world dataset taken from Sapporo City, Japan.

New vectors: Scolytus chikisanii and S. japonicus (Scolytidae) associated with Dutch elm disease in Hokkaido, Japan

ABSTRACT Scolytus esuriens is a vector of Dutch elm disease (DED) in Japan. However, small holes that were presumed to be irruption or flight holes of bark beetle species other than S. esuriens were observed at dead small branches of Japanese elms in Sapporo City, Hokkaido, Japan. In this study, bark beetles that use small branches of elm trees for breeding were surveyed as candidate DED vectors. It was determined if the causal fungi of DED, Ophiostoma ulmi and O. novo-ulmi, could be acquired from adult beetles. Two bark beetles were determined as new vectors: Scolytus chikisanii and S. japonicus. The morphology of feeding wounds on the crotches of living twigs by each vector species was investigated. Subsequently, the relative frequency of feeding wounds made by each bark beetle species was estimated based on the morphological type of feeding wounds on wilting twigs in the field. S. chikisanii and S. japonicus may have contributed more to the spread of infection than S. esuriens in the study area.

Suffusion in densely compacted Satozuka pumice sand and its impact on static loading undrained shear strength and dilation behaviour

Pumice sand of volcanic origin contains a high fraction of non-plastic fines (>40 % for Satozuka pumice sand in Sapporo, Japan). Suffusion in such soil can wash away a portion of the fine particles and alter the soil microstructure. The moisture content and degree of compaction can affect the suffusion characteristics of soil deposits, however their effect has not yet been evaluated. Future construction sites in growing Sapporo City, consisting of pumice sand, will require a high degree of compaction (over 90 % and preferably over 95 %) as this sand is prone to suffusion in spite of its dense state. The aim of this study is to assess the impact of suffusion on densely compacted pumice sand with a high proportion of fines, based on its mechanical properties, with an emphasis on shear strength and dilatancy. Firstly, the suffusion characteristics of Satozuka pumice sand were evaluated. Subsequently, undrained triaxial tests (CU¯ tests) under monotonic loading were conducted on high-density specimens, with suffusion and without suffusion, to study the impact of suffusion. It is seen in the results that the hydraulic conductivity, shear strength, stress paths, and dilatancy are all noticeably affected by suffusion. The specimens with suffusion exhibit an increase in residual shear strength and maximum deviator stress under shearing and experience an earlier occurrence of phase transformation from contraction to dilation during shearing. This tendency implies that suffusion has no significant negative impact on the deterioration of earth fill made from pumice sand and non-plastic fines, and that it persists at degrees of compaction between 80 % and 100 %.

Exposure to organophosphate flame retardants and plasticizers is positively associated with wheeze and FeNO and eosinophil levels among school-aged children: The Hokkaido study

Exposure to organophosphate flame retardants and plasticizers (PFRs) increases the risk of asthma and allergies. However, little is known about its association with type 2 inflammation (T2) biomarkers used in the management of allergies. The study investigated associations among urinary PFR metabolite concentrations, allergic symptoms, and T2 biomarkers. The data and samples were collected between 2017 and 2020, including school children (n = 427) aged 9–12 years living in Sapporo City, Japan, among the participants of “The Hokkaido Study on Environment and Children’s Health.” Thirteen urinary PFR metabolites were measured by LC-MS/MS. Allergic symptoms were assessed using the International Study of Asthma and Allergies in Childhood questionnaire. For T2 biomarkers, the peripheral blood eosinophil counts, fraction of exhaled nitric oxide level (FeNO), and serum total immunoglobulin E level were measured. Multiple logistic regression analysis, quantile-based g-computation (qg-computation), and Bayesian kernel machine regression (BKMR) were used to examine the associations between the health outcomes of the individual PFRs and the PFR mixtures. The highest concentration of PFR was Σtris(1-chloro-isopropyl) phosphates (ΣTCIPP) (Median:1.20 nmol/L). Tris(1,3-dichloro-2-propyl) phosphate (TDCIPP) was significantly associated with a high odds ratio (OR, 95%CI:1.36, 1.07–1.72) for wheeze. TDCIPP (OR, 95%CI:1.19, 1.02–1.38), Σtriphenyl phosphate (ΣTPHP) (OR, 95%CI:1.81, 1.40–2.37), and Σtris(2-butoxyethyl) phosphate (ΣTBOEP) (OR, 95%:1.40, 1.13–1.74) were significantly associated with increased odds of FeNO (≥35 ppb). ΣTPHP (OR, 95%CI:1.44, 1.15–1.83) was significantly associated with high eosinophil counts (≥300/μL). For the PFR mixtures, a one-quartile increase in all PFRs (OR, 95%CI:1.48, 1.18–1.86) was significantly associated with high FeNO (≥35 ppb) in the qg-computation model. The PFR mixture was positively associated with high FeNO (≥35 ppb) and eosinophil counts (≥300/μL) in the BKMR models. These results may suggest that exposure to PFRs increases the probability of asthma, allergies, and T2 inflammation.

Wild bee surveys across 60 years reveal remarkable reduction of bee abundance in urban green areas in northern Japan

AbstractLong‐term monitoring of wild bee communities at fixed locations using a consistent sampling procedure has been rare, although declines in their diversity and abundance due to anthropogenic impacts are a major concern. At two sites in urban green areas in Sapporo city, northern Japan, where wild bee surveys were conducted in 1959, 1979, 1989, 2018, and 2019, the number of individuals of bee genera was recorded. Patterns of seasonal changes in bee abundance collected at weekly censuses differed between 1979–1989 and 2018–2019. The total bee abundance collected in annual surveys consisting of standardized censuses demonstrated 50% and 41% declines at the two sites from 1959–1989 to 2018–2019. Among the 16 genera found in the surveys, 3 abundant genera, Andrena, Lasioglossum, and Ceratina, always exhibited lower abundance in 2018–2019 than in 1959–1989 at both sites. The remarkable declines in wild bee abundance should be examined in relation to various possible factors of anthropogenic impacts.

Tracing morphological characteristics of activated sludge flocs by using a digital microscope and their effects on sludge dewatering and settling

ABSTRACT In wastewater treatment by the activated sludge (AS) process, settleability and dewaterability of AS are key issues that are directly related to the treated water quality and sludge treatment costs. Several studies investigated the relationship between the shape of AS flocs and their settling/dewatering property. To quantify the floc morphology, it is imperative to attach a camera to a microscope or move the stage manually. Hence, labour and equipment costs may increase. In this study, by combining a digital microscope and an automatic stage, more than 100 magnified floc images were rapidly obtained from one AS sample dropped on a slide glass, and shape parameters were collectively calculated using an analysis software. During 1-year monitoring of four wastewater treatment plants in Sapporo City (Hokkaido, Japan), the morphological parameters and extracellular polymeric substances (EPS) quantity/quality of AS were analyzed on the basis of their correlation to the time to filtration (TTF) and sludge volume index (SVI), which are indicators for describing the dewatering and settling properties of AS, respectively. In one plant, larger, denser, and smoother flocs tended to contain less EPS and exhibited better sludge dewaterability. In another plant, larger, denser, and smoother flocs were considered to contribute to better settlement. Especially, an equivalent high-density floc diameter and the ratio of mixed liquor suspended solids (MLSS) concentration to the total floc area were commonly suggested to explain AS dewaterability and settleability.

Changes in common areas of condominiums in Sapporo

ABSTRACT Many Asian countries are experiencing rapid urbanization. Japan is no exception, and urbanization is progressing in many regions. This study focuses on condominiums that have supported Japan’s urbanization and captures the evolution of their common areas. We target condominiums built in Sapporo City and analyze changes over a 40-year period based on data books and pamphlet drawings. The survey results revealed the following four points: 1) We determined the trends of the reduction in site and building areas and the move to an increase in number of floors. 2) In recent years, the installation rates of various common facilities, such as storage rooms, have increased. 3) We observed that the separation between public and private became clear with the progress of common facilities that had been moved indoors and outdoors, and in particular, the progressing trend of consolidating common facilities on the first floor of residential buildings. 4) We ascertained that, accompanying the consolidation of common facilities on the first floor, the number of flow lines from the inside to common facilities such as “parking lots” increased, where the original relationship with the outside in particular had been enhanced.

Isolation vulnerability analysis in road network: Edge connectivity and critical link sets

This article focuses on vulnerability in transportation systems because of large-scale disasters. We proposes an index of isolation vulnerability as a new metric for network vulnerability analysis. Isolation vulnerability covers the situation in which supporting bases and receiving bases in a network cannot connect when some links are degraded due to external forces imposed on the network. Isolation vulnerability is derived as a solution of the maximum flow problem for a one-to-one network extended for supporting bases and receiving bases. A single set of link combinations does not necessarily exist that defines an isolation vulnerability, i.e., a set that is isolation-critical. A method of enumerating all of these critical link sets is provided and applied to the road network in Sapporo city, Japan, to identify highly vulnerable public shelters and analyze their characteristics.

Japan DAMT COVID-19 response. The Temporary Medical Facility for Hospitalization Waiting and Doctor Home Response System in Sapporo City, Hokkaido

Introduction:In Japan, the response to COVID-19 has been a disaster response. In May 2021, the number of patients requiring hospitalization increased rapidly in Sapporo City, Hokkaido. Almost all medical institutions and clinics were overcrowded, and patients were forced to wait at home. Sapporo City requested a response from the Japan Disaster Medical Assistance Team (DMAT).Method:DMAT collaborated with the Sapporo City Public Health Center to set up a patient waiting station (The Temporary Medical Facility for Hospitalization Waiting) utilizing an unused hotel. DMAT placed the patient under medical care, provided oxygen therapy and other procedures, and coordinated hospitalization referrals. DMAT also organized a doctor home response system for patients who need emergency hospitalization and those who have returned home from The Hospital Waiting Stations.Results:64% of the patients were admitted to hospitals, 27% back to their homes, 9% were sent to residential care facilities, and 1% were sent to welfare facilities. The doctor home response system was able to redirect 52% of patients requiring emergency hospitalization.Conclusion:For the rapidly increasing number of patients with COVID-19, DMAT established a temporary medical facility and home visit system and was able to minimize the number of preventable deaths.

Impact of COVID-19 pandemic on emergency medical system and management strategies in patients with acute coronary syndrome

The global coronavirus disease-2019 (COVID-19) pandemic is associated with reduced rate of percutaneous coronary intervention (PCI). However, there were a few data showing how emergency medical system (EMS) and management strategies for acute coronary syndrome (ACS) changed during the pandemic. We sought to clarify changes on characteristics, treatments, and in-hospital mortality of patients with ACS transported via EMS between pre- and post-pandemic. We examined consecutive 656 patients with ACS admitted to Sapporo City ACS Network Hospitals between June 2018 and November 2021. The patients were divided into pre- and post-pandemic groups. The number of ACS hospitalizations declined significantly during the pandemic (proportional reduction 66%, coefficient −0.34, 95% CI −0.50 to −0.18, p < 0.001). The median time from an EMS call to hospital was significantly longer in post-pandemic group than in pre-pandemic group (32 [26–39] vs. 29 [25–36] min, p = 0.008). There were no significant differences in the proportion of patients with ACS receiving PCI, and in-hospital mortality between the groups. The COVID-19 pandemic had a significant impact on EMS and management in patients with ACS. Although a significant decline was observed in ACS hospitalizations, the proportion of patients with ACS receiving emergency PCI remained during the pandemic.

Wastewater-based prediction of COVID-19 cases using a highly sensitive SARS-CoV-2 RNA detection method combined with mathematical modeling

Wastewater-based epidemiology (WBE) has the potential to predict COVID-19 cases; however, reliable methods for tracking SARS-CoV-2 RNA concentrations (CRNA) in wastewater are lacking. In the present study, we developed a highly sensitive method (EPISENS-M) employing adsorption-extraction, followed by one-step RT-Preamp and qPCR. The EPISENS-M allowed SARS-CoV-2 RNA detection from wastewater at 50 % detection rate when newly reported COVID-19 cases exceed 0.69/100,000 inhabitants in a sewer catchment. Using the EPISENS-M, a longitudinal WBE study was conducted between 28 May 2020 and 16 June 2022 in Sapporo City, Japan, revealing a strong correlation (Pearson’s r = 0.94) between CRNA and the newly COVID-19 cases reported by intensive clinical surveillance. Based on this dataset, a mathematical model was developed based on viral shedding dynamics to estimate the newly reported cases using CRNA data and recent clinical data prior to sampling day. This developed model succeeded in predicting the cumulative number of newly reported cases after 5 days of sampling day within a factor of √2 and 2 with a precision of 36 % (16/44) and 64 % (28/44), respectively. By applying this model framework, another estimation mode was developed without the recent clinical data, which successfully predicted the number of COVID-19 cases for the succeeding 5 days within a factor of √2 and 2 with a precision of 39 % (17/44) and 66 % (29/44), respectively. These results demonstrated that the EPISENS-M method combined with the mathematical model can be a powerful tool for predicting COVID-19 cases, especially in the absence of intensive clinical surveillance.

Land use plan and changes in the land use planning system toward its realization: A case study of Sapporo City

AbstractThe purpose of this study is to clarify the long‐term evolution of land use planning and land use planning system operation, as well as the actual status of the population distribution and urban area formation at each stage, using the City of Sapporo as a case study. Sapporo City formulated its first basic urban plan in the 1959 Sapporo comprehensive city plan (SCCP). Since its launch in 1971, the Sapporo long‐term comprehensive plan (LTCP) was consistently employed as a masterplan, and land use plans have been established within it. SCCP emphasizes the need to control expansion of urban areas due to the crisis of sprawling urban proliferation. In response, LTCP developed a land use plan consisting of multiple cores and three types of residential areas sorted by their density. To achieve this goal, the land use planning system was revised. In this process, the basic approach to urban planning has remained consistent for almost half a century. Namely, “Positioning LTCPs as Urban Masterplan”, “Controlling the outward expansion of urban areas” and “Multi‐centered core urban structure and layout of residential areas” were continued. In parallel, the plan was flexibly modified in response to changing socioeconomic conditions.

Changes in mobility amid the COVID-19 pandemic in Sapporo City, Japan: An investigation through the relationship between spatiotemporal population density and urban facilities

By the end of 2021, the Omicron variant of coronavirus disease 2019 had become the dominant cause of a worldwide pandemic crisis. This demands a deeper analysis to support policy makers in creating interventions that not only protect people from the pandemic but also remedy its negative effects on the economy. Thus, this study investigated people’s mobility changes through the relationship between spatiotemporal population density and urban facilities. Results showed that places related to daily services, restaurants, commercial areas, and offices experienced decreased visits, with the highest decline belonging to commercial facilities. Visits to health care and production facilities were stable on weekdays but increased on holidays. Educational institutions’ visits decreased on weekdays but increased on holidays. People’s visits to residential housing and open spaces increased, with the rise in residential housing visits being more substantial. The results also confirmed that policy interventions (e.g., declaration of emergency and upgrade of restriction level) have a great impact on people’s mobility in the short term. The findings would seem to indicate that visit patterns at service and restaurant places decreased least during the pandemic. The analysis outcomes suggest that policy makers should pay more attention to risk perception enhancement as a long-term measure. Furthermore, the study clarified the population density of each facility type in a time series. Improving model performance would be promising for tracking and predicting the spread of future pandemics.

Educational significance and challenges of conducting the objective structured clinical examination twice for midwifery students before and after clinical training: A longitudinal single university study during 2014-2019 in Japan.

This study aimed to clarify the educational significance and issues associated with administering the objective structured clinical examination (OSCE) twice to midwifery students, i.e., before and after clinical training. In Sapporo City University in Japan, 37 assessment items of the OSCE were configured as "Overall," with 17 items as midwifery's normal delivery preparation (Part 1) and 20 items as midwifery's normal delivery assistance (Part 2). All students had attended lectures with textbooks. The first and second OSCEs were conducted before and after the clinical training, respectively. The scores of 54 students were retrospectively analyzed over 6 years (2014-2019). The results of the first and second OSCEs were compared. Statistical analysis was performed using Mann-Whitney U test, Wilcoxon signed rank-sum test, Fisher's exact test, and analysis of variance. The mean scores for "Overall" [0-37], "Part 1" [0-17], and "Part 2" [0-20] in the second OSCEs were significantly higher than those in the first OSCE (Overall: 22.7 vs 19.3, Part 1: 9.50 vs 7.71, Part 2: 13.2 vs 11.6, p<0.05, respectively). Regarding "Overall" and "Part 1," a positive correlation was observed between the first and second OSCEs, wherein the full scores of "Part 1," converted from 17 to 20 points to match the full scores of "Part 2," were significantly lower than those of Part 2 (p<0.05, respectively). There was a positive correlation between the scores of the first and second OSCEs in "Part 1" and "Part 2" (p<0.05). The scores increased between the two OSCEs, and participants could objectively grasp the knowledge and skills. The OSCEs conducted twice were useful in skilling-up the normal delivery preparation and assistance skills of midwifery students. However, developing an advanced educational method might be necessary for the midwifery students' preparation of normal delivery, because the scores in the OSCEs were lower.

Impact of the COVID-19 pandemic on changes in temperature-sensitive cardiovascular and respiratory disease mortality in Japan.

Some cardiovascular and respiratory diseases are triggered by changes in ambient temperature or extremes of temperature. This study aimed to clarify the changes in mortality associated with temperature-sensitive diseases in Japan during the COVID-19 pandemic. We used data from three major cities (Sapporo City, Tokyo 23 wards, and Osaka City) from 2010 to 2019 to determine disease mortality rates and monthly mean temperatures from April to December. If the pandemic had not occurred in 2020, the results showed that temperature-sensitive disease death counts would have increased from 324 to 980, based on a 95% confidence interval estimated from the past 10 years in Sapporo (19–56% increase in actual deaths from 2020), from 651 to 2,653 in Tokyo (10–39% increase), and from 235 to 1,343 in Osaka (8–48% increase). Analyses of meshed population data during the COVID-19 pandemic indicated that inhibiting people’s behaviour and outdoor mobility, especially in older men, caused a decrease in mortality.