BACKGROUND: Older adults in Japan have the highest drowning mortality rate globally due to frequent bathing practices. Low outdoor temperatures have been linked to bath-related deaths; however, previous studies employed limited statistical models and focused on a single prefecture. Given Japan's aging population, preventing bath-related deaths is a public health priority. This study aimed to analyze the association between outdoor temperature and bath-related drowning deaths across Japan from 1995 to 2020 (n = 110,938), examining regional variations and identifying contributing prefectural characteristics. METHODS: Daily counts of bath-related drowning deaths per prefecture were matched with daily mean temperature data from the Japan Meteorological Agency. Prefecture-level demographic and environmental data were obtained from Japan's Official Statistics. We applied a generalized additive mixed model to examine the association between daily mean temperature and bath-related drowning death risk. Meta-regression was used to identify prefecture-level modifiers. RESULTS: Bath-related drowning death risk peaked at a daily mean temperature of 1.8 °C (relative risk [RR] 9.7, 95% confidence interval [CI]: 9.5-9.9), compared with the lowest risk at 30.3 °C. The association was stronger at mid-range temperatures, particularly among males and individuals aged ≥65 years. Among prefectures, Kagoshima-the southernmost prefecture on Japan's main islands-had the highest maximum RR at 19.6 (95% CI: 16.2-23.6), while Hokkaido-the northernmost prefecture-had the lowest at 3.8 (95% CI: 3.4-4.3). Prefecture-level factors that strengthened this relationship included a lower prevalence of double-pane windows as a proxy of housing insulation and higher annual mean temperatures with ratio of RR change per one standard deviation increase of 0.76 (95% CI: 0.69-0.83) and 1.27 (95% CI: 1.18-1.37), respectively. CONCLUSIONS Warmer prefectures in southern regions exhibited greater maximum-to-minimum risk ratios compared to cooler northern prefectures. This paradoxical finding underscores the importance of region-specific interventions to reduce bath-related deaths.
Japan/epidemiology* ; Humans ; Drowning/epidemiology* ; Male ; Aged ; Female ; Baths/statistics & numerical data* ; Middle Aged ; Temperature ; Aged, 80 and over ; Adult ; Young Adult ; Risk Factors ; Adolescent

BACKGROUND: Globally, Japan has the highest drowning mortality among older adults, largely because of bathing customs. Although this mortality rate peaks in winter, the nationwide impact of outdoor temperature has not been quantified, and whether specific days carry greater risks for bathtub drowning deaths remains unclear. Therefore, we aimed to address these gaps using nationwide data from Japan. METHODS: We collected daily data on outdoor temperatures and bathtub drowning deaths (from death certificates), along with population data, across 47 prefectures from 1995-2020. A time series regression model incorporating a cyclic spline for day-of-year and a cross-basis function for outdoor temperature was used to estimate seasonality and temperature attributable fractions (AFs). Prefecture-specific estimates were pooled using meta-analysis. National holidays were defined by the Act on National Holidays. RESULTS: During the study period, 99,930 home bathtub drowning deaths were recorded. The AF for seasonality modelled with a cyclic spline for day-of-year was 77.8% (empirical confidence interval [eCI]: 76.7-78.8%), which decreased to 15.3% (eCI: 13.1-18.0%) after adjusting for outdoor temperature, indicating that outdoor temperature accounted for 80.3% of the seasonal effect. Elevated risks were observed on Sundays (relative risk = 1.16, 95% CI: 1.12-1.20), holidays (1.12, 95% CI: 1.08-1.16), New Year's Day (1.72, 95% CI: 1.61-1.84), and New Year's Eve (1.63, 95% CI: 1.52-1.74) in the adjusted model, which included a cyclic spline for day-of-year and a cross-basis function for outdoor temperature. CONCLUSION Our findings highlight the importance of mitigating the impact of outdoor temperature on bath-related death risk. Identifying high-risk days can be used to help develop targeted preventive strategies.
Seasons ; Humans ; Drowning/epidemiology* ; Japan/epidemiology* ; Temperature ; Aged ; Male ; Adult ; Female ; Middle Aged ; Child ; Young Adult ; Adolescent ; Aged, 80 and over ; Child, Preschool

OBJECTIVE: To analyze the mortality of injuries among children and adolescents aged 5 to 24 in China from 1990 to 2019, and to provide the theoretical basis for the formulation of policies related to injury prevention. METHODS: The mortality data of children and adolescents aged 5 to 24 years in China between 1990 and 2019 were obtained from Global Burden of Disease (GBD) 2019, and the change in mortality between 1990 and 2019 was described. Age-period-cohort analysis was utilized to determine the age effect, period effect and cohort effect for road injuries, drowning and self-harm. RESULTS: Injury mortality of Chinese children and adolescents aged 5 to 24 years decreased from 46.22 [95% uncertainty interval (UI): 40.88-52.12] per 100 000 to 20.36 (95%UI: 17.58-23.38) per 100 000 between 1990 and 2019. Sub-group analysis revealed a pattern that was basically consistent with the overall trend. From 1990 to 2019, drowning declined from the first leading cause of injury death among children and adolescents aged 5 to 24 years in China to the second while road injuries became the one which caused the most death among them, and self-harm was the third leading cause of injury death. The top three causes of injury death in each subgroup were basically the same as the overall, but the order was different in each subgroup. Age-period-cohort analysis showed that the death risk of road injuries, drowning, and self-harm all decreased with period and cohort. Aside from that, the death risk of road injuries showed a U-shape trend, which decreased at first but increased soon afterwards, with the increase of age, while the death risk of drowning decreased with age and the death risk of self-harm increased with age. CONCLUSION In China, the injuries mortality among children and adolescents aged 5 to 24 years has decreased over the last three decades. However, specific cause-related injury deaths, manifested differently in different sub-groups. Targeted policies and intervention should be proposed to reduce the mortality of children and adolescents in accordance with the characteristics of injuries death in different genders and age groups.
Adolescent ; Asians ; Cause of Death ; Child ; China/epidemiology* ; Drowning ; Female ; Global Burden of Disease ; Humans ; Infant ; Male ; Wounds and Injuries

Objective: To analyze the trajectory of drowning and road traffic injury mortality among children aged 5-14 years in China from 2008 to 2019. Methods: Mortality data of unintentional injuries were from the Mortality Surveillance Data Set of National Disease Surveillance System from 2009 to 2018 and grouped by regions, urban and rural areas, genders, and age groups. The trajectory model was used to analyze the trend of drowning and road traffic injury mortality with years. Results: The mortality of drowning and road traffic injury showed a similar trend. In the trajectory model of drowning mortality, east, middle and west rural boys and western urban boys of all ages belonged to the high mortality group. The moderate mortality group included eastern urban boys and western girls aged 5-9 years and also contained eastern and middle urban boys and western urban girls aged 10-14 years. The other combinations belonged to the low mortality group. In the trajectory model of road traffic injury mortality, western urban boys, all rural boys and western rural girls aged 5-9 years, middle and western rural boys and western urban boys aged 10-14 years belonged to the high mortality group. Eastern urban girls aged 5-9 years and 10-14 years belonged to the low mortality group. The other combinations belonged to the moderate mortality group. Conclusion: There are different groups in the trajectory model of drowning and road traffic injury mortality among children in China. Identifying the trajectory of injury mortality is helpful to carry out more targeted prevention in China.
Accidental Injuries ; Accidents, Traffic ; Child ; China/epidemiology* ; Drowning ; Female ; Humans ; Male ; Rural Population ; Urban Population ; Wounds and Injuries

OBJECTIVES: To explore the research hotspots and development trends of the field of forensic drowning from 1991 to 2020 by bibliometrics methods. METHODS: Based on Web of Science, CNKI database, Wanfang Data knowledge service platform, python 3.9.2, CiteSpace 5.8.R3, Gephi 0.9.2, etc. were used to analyze the publishing trends, countries/regions, institutions, authors and topics of the study on drowning. RESULTS: A total of 631 English literature were obtained, including 59 articles from Chinese authors, and 386 Chinese literature were obtained. The Chinese and English journals with the largest number of related literatures were Chinese Journal of Forensic Science (80 articles) and Forensic Science International (106 articles), respectively. Japan published the most articles in English, and China ranked third. Osaka City Univ (Japan, 28 articles) published the most English articles, and Guangzhou Forens Sci Inst (China, 22 articles) ranked second. Among Chinese literature, Guangzhou Forens Sci Inst (32 articles) published the most. The topic analysis of Chinese and English literature showed that diatom examination, virtual autopsy, postmortem biochemical examination, the nature of death, and postmortem submersion interval were the hot spots of current research, but English literature had more studies on new technologies and methods, while Chinese literature was more inclined to practice, application and experience summary. CONCLUSIONS The number of literature in forensic medicine on drowning is relatively stable. The scope of international and domestic collaborations in this field is still limited. The automated examination of diatoms, the establishment of diatom DNA barcodes and virtual autopsy will be the most important research hotspots in the coming period and are expected to achieve breakthroughs in drowning diagnosis, drowning location inference, postmortem submersion interval estimation, etc.
Bibliometrics ; China/epidemiology* ; Drowning/diagnosis* ; Forensic Medicine ; Humans ; Publications

Objective To study the preference relation between residence, sex, age and causes of accidental death of Chinese residents. Methods In this study, 72 residence-sex-age groups and 8 causes of accidental death were qualitatively and quantitatively analyzed by correspondence analysis using the official statistical yearbook issued from 2014 to 2018, and the preference values were calculated. Results Among the 576 pairs of correspondences between the residence-sex-age groups and causes of accidental death, 352 pairs （61.11%） showed a preference relation （preference value>0）. In terms of residence and sex, accidental death preference among Chinese residents was higher in rural areas than in urban areas, and males were higher than females. In terms of the causes of accidental death, the overall risk of accidental mechanical asphyxia and motor vehicle accidents was the highest among all age groups of Chinese residents. In terms of age, with the increase of age, the preference value of accidental death of Chinese residents showed a trend of first increasing and then decreasing. The comparative analysis results of the preference values of various causes of accidental death in different age groups showed that motor vehicle traffic accidents, accidental poisoning, death by crush and electric shock were more likely to occur in the working age group between 20 and 59 years old, accidental fall and fire were more likely to occur in the elderly group over 80 years old, and drowning and accidental mechanical asphyxia were more likely to occur in the minor group between 1 and 19 years old. Conclusion There are different preference relations between residence-sex-age groups and causes of accidental death in China. Therefore, effective control strategies and measures should be formulated for Chinese residents with preference for accidental death.
Accidental Falls ; Accidents, Traffic ; Adult ; Aged ; Asphyxia/etiology* ; China/epidemiology* ; Drowning ; Female ; Humans ; Male ; Middle Aged ; Young Adult

Hot bath-related deaths occur occasionally in Korea, particularly in the winter season among elderly people. The postmortem determination of the cause and manner of death is often difficult because the investigation depends predominantly on postmortem external examination. Moreover, the pathogenesis of sudden death during immersion in a hot bath tub is not easily explained. Confusion regarding the manner of death, whether accidental or natural, causes some conflicts in the compensation of life insurance. This study reviewed the literature, particularly Japanese studies about epidemiology, pathophysiology, and the disputes regarding determination of the manner of death. We concluded that the cause and manner of death are not as simple as only natural disease or drowning; there are complicated cases mixed with accidental and natural causes. Extensive epidemiological studies and thorough investigation, including full autopsy and toxicologic studies, are essential for comprehensive understanding of hot bath-related deaths in Korea.
Aged ; Asian Continental Ancestry Group ; Autopsy ; Baths ; Cause of Death ; Compensation and Redress ; Death, Sudden ; Dissent and Disputes ; Drowning ; Epidemiologic Studies ; Epidemiology ; Humans ; Immersion ; Insurance, Life ; Korea ; Seasons

OBJECTIVES: To analyze the relationship between the suicide method and the sex, age, education background and cause of suicide to provide reference for the forensic identification of suicide. METHODS: After scene investigation, external body examination, autopsy and case investigation, 124 identified suicide cases which happened in recent three years in Wuhua district in Kunming were collected. Analytical methods as chi-square test and descriptive statistics were performed by SPSS 22.0. RESULTS: In all the suicide cases, male to female ratio was 1.53∶1. The suicide methods were mainly fatal fall, hanging and drowning. The ratio of local to non-native residents was 1∶1. The suicide rate in the people with primary school or junior middle school education level was highest. The group of >10-50 years tended to choose fatal fall suicide and people over 60 years were more likely to choose hanging. People with different academic background tended to choose fatal fall suicide. The suicide methods as fatal fall and hanging were chosen because of mental and physical diseases and economic problems, while the suicides with emotional problems were more likely to choose fatal fall and poisoning. CONCLUSIONS Suicide belongs to a kind of complex cases. For the cases of suspected suicide, complete exploration and overall consideration should be done to determine the nature of cases based on comprehensive analysis of all the influence factors.
Adolescent ; Adult ; Age Distribution ; Aged ; Autopsy ; Cause of Death ; Child ; China/epidemiology* ; Drowning/psychology* ; Female ; Humans ; Incidence ; Male ; Mental Disorders/psychology* ; Middle Aged ; Sex Distribution ; Suicide/statistics & numerical data* ; Young Adult

OBJECTIVETo study the trend of accidental death among children under 5 years of age in Beijing.

METHODSCases of death in children under 5 years old in Beijing, during 2003-2012 were collected, to analyze the strength and trends of accidental death, main causes of accident and its epidemiological features.

RESULTSThe overall accidental death was 8.47% of all death among children under 5 years old in Beijing during 2003-2012. During these 10 years, data showed a downward trend on the mortality rates on injuries (P < 0.05), especially on drowning, in 1-4 year old and rural children under five years of age. In 2012, the accidental death rate of children under five was 6.37/105. The 5 main causes of accidental deaths were suffocation, traffic accident, falling, poisoning and drowning, in order of size. The main causes of death were suffocation in the 0-1 year group, suffocation and traffic accident in the 1-2 year group and traffic accident in the 3-4 year group. The proportion of deaths due to traffic accident increased gradually with age. Area distribution showed that accidental deaths mainly happened in rural area (52.19%), with two main types as traffic accident and suffocation.

CONCLUSIONThe reduction of accidental death rate among children under 5 years old in Beijing mainly was caused by the decline of accident mortality in 1-4 year old and children in the rural areas. Our data suggested that the focus in reducing the accidental death rate among children under 5 years old in Beijing should target on the prevention of infant suffocation and traffic accidents among the 1-4 year old, with rural areas in particular.

Accidents ; mortality ; Accidents, Traffic ; mortality ; Asphyxia ; mortality ; Cause of Death ; Child Mortality ; Child, Preschool ; China ; epidemiology ; Drowning ; mortality ; Female ; Humans ; Infant ; Male ; Suicide

OBJECTIVE: To analyze the features of drowning victims with psychiatric disorders to support further investigation on such cases. METHODS: One hundred and five archives of drowning victims with psychiatric disorders from January 2010 to June 2014 in Harbor Public Security Subbureau, Shanghai Public Security Bureau were reviewed. The decedents' general information, autopsy findings, case investigation data and disease histories were statistically analyzed. RESULTS: Of the 105 cases, 104 were suicides. Most decedents were poorly educated. Most suicides occurred in warm climate, and the corpses were usually found within 2 days. Most decedents had no suicide history and notes, but had abnormal mental or behavior changes before suicide. Depression, depression status and schizophrenia were the main types of psychiatric disorders, and only 9 decedents had received regular therapies before their deaths. CONCLUSION Mental disorder is a high risk factor in the drowning victims. Guardians should be aware of psychotic abnormal behaviors, especially during warm climate seasons.
China/epidemiology* ; Depression/epidemiology* ; Depressive Disorder/epidemiology* ; Drowning/psychology* ; Female ; Humans ; Male ; Mental Disorders/psychology* ; Psychotic Disorders ; Retrospective Studies ; Risk Factors ; Schizophrenia ; Seasons ; Suicide/statistics & numerical data*