Temporal Trends of Suicide Mortality in Mainland China: Results from the Age-Period-Cohort Framework

Trends in injury-related mortality among residents of Jiangsu Province from 2012 to 2021: an age-period-cohort analysis

Objective

We investigated the temporal trends and examined age-, period-, and cohort-specific effects of injury-related deaths among residents in Jiangsu to provide evidence for future injury prevention.

Methods

This study included 406,936 injury deaths from the Jiangsu provincial population death registration system. The average annual percent change (AAPC) in age-standardized mortality rates (ASMRs) was analyzed using joinpoint regression. Age-period-cohort models were generated to explore the effects of age, period, and birth cohort effects on mortality risk.

Results

ASMRs for all injuries (AAPC = -2.3%), road traffic accidents (AAPC = -5.3%), suicide (AAPC = -3.8%), and drowning (AAPC = -3.9%) showed a downward trend during 2012-2021(all p < 0.05), while unintentional falls showed an upward trend (AAPC = 5.1%, p < 0.05). From 2012 to 2021, the age-standardized mortality rates (ASMRs) for four primary types of injuries consistently exhibited higher among males compared to females, with rural regions displaying higher ASMRs than urban areas. Trends in ASMRs for road traffic accidents, drowning, and unintentional falls by sex and urban/rural areas were consistent with overall trends. Significant age, cohort, and period effects were identified in the trends of injury-related deaths for both sexes in Jiangsu. The age effect showed that the highest age effect for injury-related deaths was for the ages of 85 years and above, except for suicide, which was for the ages 80-84 years. Between 2012 and 2021, the period effect on road traffic accidents declined, while that on accidental falls increased. Initially, the period effect on suicide decreased but then rose, peaking in 2012 with a Relative Risk (RR) of 1.11 (95% CI: 1.04-1.19). Similarly, the period effect on drowning initially declined before rising, with the highest effect observed in 2013, at an RR of 1.12 (95% CI: 1.07-1.19). The highest cohort effects for road traffic accidents were observed in the 1957-1961 group, for accidental falls in the 1952-1956 group, and for both drowning and suicide in the 1927-1931 group.

Conclusion

The mortality rate of unintentional falls has been increasing. Older adults are at high risk for the four leading injuries. The improvements in mortality rates can be attributed to advancements in education, urbanization, and the promulgation and implementation of laws and policies.

The long-term changing patterns of suicide mortality in China from 1987 to 2020: continuing urban-rural disparity

BACKGROUND

Over the past three decades, China has experienced significant changes in urban-rural, gender, and age-specific suicide mortality patterns. This study aimed to investigate the long-term trends in suicide mortality in China from 1987 to 2020.

METHODS

Suicide mortality data were obtained from China's National Health Commission. Joinpoint regression analysis was used to examine changes in trends and age-period-cohort modeling to estimate age, period, and cohort effects on suicide mortality from 1987 to 2020. Net drift, local drift, longitudinal age curves, and period relative risks were also calculated.

RESULTS

Crude and age-standardized suicide mortality in China showed continuing downward trends from 1987 to 2020, with a more pronounced decrease in rural areas (net drift = -7.07%, p<0.01) compared to urban areas (net drift = -3.41%, p<0.01). The decline curve of urban areas could be divided into three substages. Period and cohort effects were more prominent in rural areas. Suicide risk was highest among individuals aged 20-24 and gradually increased after age 60. Females, particularly those of childbearing age, had higher suicide risk than males, with a reversal observed after age 50. This gender reversal showed distinct patterns in urban and rural areas, with a widening gap in urban areas and a relatively stable gap in rural areas.

CONCLUSIONS

Suicide mortality in China has consistently declined over the past three decades. However, disparities in age, gender, and urban-rural settings persist, with new patterns emerging. Targeted suicide prevention programs are urgently needed for high-risk groups, including females of childbearing age and the elderly, and to address the slower decrease and reversing urban-rural gender trends.

Temporal trends in mortality of tuberculosis attributable to high fasting plasma glucose in China from 1990 to 2019: a joinpoint regression and age-period-cohort analysis

Background

Nowadays, high fasting plasma glucose (HFPG) has been identified as the important risk factor contributing to the increased burden of diseases. But there remains a lack of research on tuberculosis (TB) mortality specifically attributable to HFPG. Thus, this study aims to explore the long-term trends in HFPG-related TB mortality in China from 1990 to 2019.

Methods

Data on HFPG-related TB mortality were obtained from the Global Burden of Disease (GBD) Study 2019. Analyzing the data using joinpoint regression and age-period-cohort methods adjusting for age, period, and cohort allowed us to assess the trends in TB mortality due to HFPG.

Results

The age-standardized mortality rates (ASMRs) of TB attributable to HFPG exhibited a downward trend in China from 1990 to 2019, with an average annual percentage change (AAPC) of -7.0 (95% CI, -7.5 to -6.6). Similar trends were found for male (AAPC of -6.5 [95% CI, -7.0 to -6.0]) and female (AAPC of -8.2 [95% CI, -8.5 to -7.9]), respectively. Local drifts curve with a U-shaped pattern reflected the AAPC of TB mortality due to HFPG across age groups. The greatest decline was observed in the age group of 60-64 years. The mortality rates related to HFPG first increased and then decreased with increasing age, peaking in the 55-59 age group. Our analysis of the period and cohort effects found that the rate ratios of TB mortality due to HFPG have decreased over the past three decades, more prominently in women. It is noteworthy that while both genders have seen a decline in HFPG-attributable TB mortality and risk, men have a higher risk and slightly less significant decline than women.

Conclusion

The present study shows that HFPG-related ASMRs and risk of TB in China decreased over the last 30 years, with similar trends observed in both men and women. In order to attain the recommended level set by the WHO, the effective strategies for glycemic control and management still needed to be implemented strictly to further decrease the burden of TB.

Trends of suicide rates by gender and residence in China from 2002 to 2019

Objective

China has undergone tremendous social changes in the last few decades. This study aimed to research the trends of the suicide rates from 2002 to 2019, and to differentiate effects attributable to age, period, and cohort by gender and residence in China.

Methods

Suicide mortality data were obtained from China's Ministry of Health Vital Registration System. Joinpoint regression model was used to estimate the average annual percentage change (AAPC) of the suicide rates and ratios by gender and residence. The age-period-cohort framework was performed to analyze the underlying mechanisms for suicide mortality trends.

Results

Over the observation period, the significant decrease in suicide mortality rates in China for the economic development and urbanization was observed but to different degrees across gender and regional subgroups. The male-to-female ratio of suicide rates increased year by year (AAPC: 1.9%, 95% CI: 0.2% to 3.7%) while the urban-rural ratio changed little (AAPC: 0.9%, 95% CI: -1.8% to 3.7%). The age-period-cohort analysis revealed a marked increased effect of age and overall decreased effect of both period and cohort on suicide mortality rates. However, the recent cohort has presented an inversely increasing effect.

Conclusion

The suicide rate has fallen sharply in China which has undergone tremendous socioeconomic changes. The varied changes in the suicide rate of different residence-, gender-, and age-groups as well as the age, period, and cohort effect on suicide risk further indicate the relationship of development and the suicide rates may be neither static nor identical on different subgroups in a rapidly changing society.

Risk factor analysis and nomogram construction for predicting suicidal ideation in patients with cancer

BACKGROUND

Suicidal ideation in cancer patients is a critical challenge. At present, few studies focus on factors associated with suicidal ideation, and predictive models are still lacking. This study aimed at investigating the risk factors for suicidal ideation among cancer patients, and developed a predictive nomogram to screen high risk cancer patients for early prevention and intervention.

METHODS

A questionnaire survey was conducted among cancer patients between May 2021 and January 2022. The factors associated with suicidal ideation were used to construct a multivariate logistic regression model, which was visualized as a predictive nomogram to evaluate the risk of suicidal ideation. Areas under the curve, calibration plot, decision curve analysis, and internal and external validation were used to validate the discrimination, calibration and clinical usefulness of the model.

RESULTS

A total of 820 patients with cancer were recruited for this study and 213 (25.98%) developed suicidal ideation. Levels of demoralization, depression and cancer staging, marital status, residence, medical financial burden, and living condition were influence factors for suicidal ideation. Comparing nomogram with Self-rating Idea of Suicide Scale (SIOSS), the nomogram had a satisfactory discrimination ability with an AUC of 0.859 (95% CI: 0.827-0.890) and 0.818 (95% CI: 0.764-0.873) in the training and validation sets, respectively. The calibration plot and decision curve analysis revealed that this nomogram was in good fitness and could be beneficial in clinical applications.

CONCLUSIONS

Suicidal ideation is common in cancer patients. Levels of demoralization, depression and cancer staging were independent predictors of suicidal ideation. The nomogram is an effective and simple tool for predictive suicidal ideation in cancer patients.

Trends in the Prevalence of Hypertensive Heart Disease in China From 1990 to 2019: A Joinpoint and Age–Period–Cohort Analysis

To the best of our knowledge, no comprehensive estimates of the descriptive epidemiology of and trends in hypertensive heart disease (HHD) in China have been reported. In this study, the temporal trends in the prevalence of HHD in China from 1990 to 2019 were estimated using an age–period–cohort model. Data related to HHD burden were collected from the Global Burden of Disease Study 2019. From 1990 to 2019, HHD prevalence in China showed decreasing trends in both sexes combined (average annual percentage change [AAPC]: −0.2%, 95% confidence interval (CI: −0.3% to −0.2%) and in males (AAPC: −0.5%, 95% CI: −0.5% to −0.4%), but significant increases in the age groups of 15–19, 20–24, …, and 60–64 years. The age effect analysis showed an increase in HHD prevalence from 50 to 94 years in both males and females, the period effect analysis showed a slight increase in HHD prevalence from 2009 to 2019 in females, and the cohort effect analysis showed a consistent decline in HHD prevalence from earlier to later birth cohorts in both males and females.

Trends in suicide rates and the case-fatality of pesticide self-poisoning in an agricultural county in china, 2009 to 2014

BACKGROUND

Suicide rates in China have declined substantially in the last two decades, however, the correlates of the decreases are still unclear.

METHODS

Using hospital-based suicidal acts registry system in Meixian county, we reviewed all episodes of suicidal behaviors presented at hospitals from 2009 to 2014. The data was combined with the suicides reported in the same period by the county's Center for Disease Prevention and Control. Stratified by gender and method, age-standardized incidences of suicide death, suicide attempts, suicidal acts, as well as the case-fatalities of suicidal acts, were calculated. Joinpoint regression analysis was applied to test the time trends changes of the annual incidences and case-fatalities. Correlation coefficients between suicide rates and case-fatality were estimated.

RESULTS

Age-standardized suicide rates among females declined by 20.4% per year, meanwhile, overall suicide rates were characterized by downward trend without statistical significance. The annual proportions of suicide deaths by pesticide self-poisoning ranged from 57.1% to 82.6%. There were positive or marginally positive correlations between suicide rates and case-fatalities of suicidal acts in gender- and method-specific groups (r values range from 0.77 to 0.89).

LIMITATIONS

Underreporting in the hospital-based registry system and misclassification in the death reporting system. Changes in other related factors are not yet accessible.

CONCLUSION

Suicide rates in females declined prominently in Meixian from 2009 to 2014, even though overall suicide rates remained steady. Pesticide ingestion were most common suicide method. Restriction of pesticide and reduction in the case-fatality are critical targets of suicide prevention in rural China.

Psychological characteristics of suicide attempters among undergraduate college students in China: a cross-sectional study

BACKGROUND

There is a need to understand the psychological characteristics of suicide attempters to prevent future suicide attempts. This study aims to examine potential differences between individuals who have attempted suicide and those who have not done so, on several risk and protective measures.

METHOD

Participants were 11,806 undergraduate students from seven provinces in China, of which 237 reported a non-fatal suicide attempt. We used the random numbers generator function within the SPSS to randomly select a control subset of 1185 participants to be used as the comparison group based on a 1:5 case-control ratio. Scores on three commonly used risk measures (depression, hopelessness, and psychache) and three protective measures (social support, self-esteem, and purpose in life) for suicidality were adopted to compare the responses of the two groups.

RESULTS

Suicide attempters had indicated higher Median scores for all three risk factor measurements. Suicide attempters also reported significantly lower Median scores for all three protective factor measurements compared to non-suicide attempters. The results suggest that the suicide attempters' group had higher risks of suicidality compared to the non-attempter group.

CONCLUSIONS

Suicide attempters continued to report higher scores of risk factors and lower scores of protective factors, indicating that they may continue to be at a higher likelihood of a suicide attempt. Key protective factors should be identified for each individual in order to deliver appropriate clinical interventions to reduce their risk of reattempting.

Time Trends and Predictions of Suicide Mortality for People Aged 70 Years and Over From 1990 to 2030 Based on the Global Burden of Disease Study 2017

Background: High suicide rate in the elderly is an important global public health problem but has not received the attention it deserves. This study aimed to examine time trends of suicide mortality for people aged 70 years and over by sex, age, and location from 1990 to 2017, and to provide predictions up to 2030. Methods: Using data from the Global Burden of Disease study 2017, we presented elderly suicide mortality changes and compared the patterns for the elderly with that for all ages. We estimated associations between socio-demographic index (SDI) and suicide mortality rates using a restricted cubic spline smoother, and predicted suicide mortality rates up to 2030. Results: In 2017, 118,813 people aged 70 years and over died from suicide, indicating a mortality rate of 27.5 per 100,000, with the highest rates in Eastern Sub-Saharan Africa, Western Sub-Saharan Africa, and Central Sub-Saharan Africa, and for countries and territories, the highest were in South Korea, Zimbabwe, Lesotho, Mozambique, and Senegal. Between 1990 and 2017, suicide mortality rate for the elderly aged 70 years and over decreased globally (percentage change -29.1%), and the largest decreases occurred in East Asia, Southern Latin America, and Western Europe. Nationally, the largest decrease was found in Chile, followed by Czech Republic, Hungary, Turkey, and Philippines. For most countries, the elderly mortality rate was higher than the age-standardized rate, with the largest percentage differences in China and countries in Sub-Saharan Africa. The elderly suicide mortality rate decreased as SDI increased, except for a slight rebound at mid to high SDI. According to projections, 10 out of 195 countries were expected to meet the SDGs indicator of a third reduction by 2030. Conclusions: Variability in suicide mortality rates for the elderly aged 70 years and over by sex, age, region, country, and SDI can guide preventive policies, but causes of the variability need further study. Comprehensive strategies should be adopted to reduce suicide rates and close the gap to the 2030 SDGs.

Historical trends in breast Cancer among women in China from age-period-cohort modeling of the 1990-2015 breast Cancer mortality data

Background

Evidence on historical trends extracted embedded in recent data can advance our understanding of the epidemiology of breast cancer for Chinese women. China is a country with significant political, socioeconomic, and cultural events since the 1900s; however, no such studies are reported in the literature.

Methods

Age-specific mortality rates of breast cancer during 1990–2015 in China were analyzed using APC modeling (age-period-cohort modeling) method. Net effect from birth cohort was derived to measure cancer mortality risk during 1906–1990 when no mortality data were collected, and net effect from time period was derived to measure cancer mortality risk during 1990–2015 when data were collected. Model parameters were estimated using intrinsic estimator, a novel method to handle collinearity. The estimated effects were numerical differentiated to enhance presentations of time/age trend.

Results

Breast cancer mortality rate per 100,000 women increased from 6.83 in 1990 to 12.07 in 2015. After controlling for age and period, the risk of breast cancer mortality declined from 0.626 in 1906–10 to − 1.752 in 1991–95 (RR = 0.09). The decline consisted of 3 phases, a gradual phase during 1906–1940, a moderate phase with some fluctuations during 1941–1970, and a rapid phase with large fluctuations during 1971–1995. After controlling for age and cohort, the risk of breast cancer mortality increased from − 0.141 in 1990 to 0.258 in 2015 (RR = 1.49) with an acceleration after 2005. The time trends revealed by both the cohort effect and the period effect were in consistency with the significant political and socioeconomic events in China since the 1900s.

Conclusions

With recent mortality data in 1990–2015, we detected the risk of breast cancer mortality for Chinese women over a long period from 1906 to 2015. The risk declined more than 90% from the highest level in 1906–10 to the lowest in 1990–95, followed by an increase of 49% from 1990 to 2015. Findings of this study connected historical evidence with recent data, supporting further research to exam the relationship between development and risk of breast cancer for medical and health decision-making at the population level and prevention and treatment at the individual level.

Suicide mortality in Spain (1984-2018): age-period-cohort analysis

OBJECTIVE

To assess the effects of age, period and cohort suicide mortality trend in Spain (1984-2018).

METHODS

Mortality and population data were obtained from the National Institute of Statistics. The analysis of the effect of age, period of death and birth cohort on the evolution of suicide mortality in the period 1984-2018 was performed using a web tool for age-period-cohort analysis provided by the Division of Cancer Epidemiology and Genetics of the National Cancer Institute of the USA.

RESULTS

Rates increase with age (age effect) in both sexes. The period effect shows, in males, an increase over the period 1984-1998 followed by a significant decrease until 2018. In females, rates remain stable over the period 1987-2002, decrease during 2007-2012 (p < 0.05) and eventually stabilise. In both males and females, the risk decreases in each successive birth cohort between 1904 and 1939. Subsequently, the risks increase until the birth cohort of the period 1964-1974 after which the risk decreases for males and remains stable for females.

CONCLUSION

A better understanding of the effects of the birth cohort could open new doors in suicide prevention.

Plasma brain-derived neurotrophic factor (BDNF) concentration and the BDNF Val66Met polymorphism in suicide: a prospective study in patients with depressive disorder

Purpose

The relationship was investigated between brain-derived neurotrophic factor (BDNF) concentrations, a BDNF polymorphism (196G>A), and the response to selective serotonin reuptake inhibitors (SSRIs) among Chinese patients with major depressive disorder (MDD).

Patients and methods

A total of 125 patients and 91 healthy controls were enrolled. The disease progression and treatment responses were evaluated using the Hamilton depression rating scale (HAMD24), the Hamilton anxiety scale, the Beck depression index, and BDNF concentrations at the baseline, 4, 8, and 12 weeks after treatment. Responders were defined as patients with at least a 50% decrease in the HAMD24.

Results

The BDNF concentrations were significantly lower in MDD (947±297 vs 1187±236 pg/mL, p=0.019), in MDD with attempted suicide than those without (779±231 vs 993±298, p=0.024) at the baseline. The BDNF concentrations remarkably increased in response to SSRI treatment. Significant correlations were noted between the BDNF concentrations and suicide ideation or attempted suicide (p<0.01), but not with HAMD24 or depression. BDNF 196G>A correlated with neither suicide ideation nor treatment responses.

Conclusion

BDNF concentrations were significantly lower in patients with attempted suicide/ideation. BDNF concentrations could serve as a response marker for antidepressant treatment in MDD.

Trends in Diabetes Mortality by Gender in Urban and Rural Areas in China From 2003 to 2012: An Age-Period-Cohort Analysis

We aimed to provide updated estimates for the trends and the effects attributable to age, period, and cohort by gender in urban and rural areas in China. The data were based on the vital registration system in China from 2003 to 2012. The annual percentage change used Joinpoint Regression Analysis. Spline functions were fitted to the age-period-cohort analysis. The average age-adjusted diabetes mortality rate was higher in women than in men, and it was higher in urban than in rural residents among both genders. The trend analysis of diabetes showed a favorable pattern among urban residents in both genders. Mortality increased with age, and compared with period and cohort effects, age effects were the most important risk factor in diabetes mortality. Although the overall trends in diabetes mortality decelerated, aging and rural-urban differences could still be driving the epidemic underlining a continued need for the priorities for health care programs to focus on predictors in diabetes mortality.

Bans of WHO Class I Pesticides in Bangladesh-suicide prevention without hampering agricultural output

Background

Pesticide self-poisoning is a major problem in Bangladesh. Over the past 20-years, the Bangladesh government has introduced pesticide legislation and banned highly hazardous pesticides (HHPs) from agricultural use. We aimed to assess the impacts of pesticide bans on suicide and on agricultural production.

Methods

We obtained data on unnatural deaths from the Statistics Division of Bangladesh Police, and used negative binomial regression to quantify changes in pesticide suicides and unnatural deaths following removal of WHO Class I toxicity HHPs from agriculture in 2000. We assessed contemporaneous trends in other risk factors, pesticide usage and agricultural production in Bangladesh from 1996 to 2014.

Results

Mortality in hospital from pesticide poisoning fell after the 2000 ban: 15.1% vs 9.5%, relative reduction 37.1% [95% confidence interval (CI) 35.4 to 38.8%]. The pesticide poisoning suicide rate fell from 6.3/100 000 in 1996 to 2.2/100 000 in 2014, a 65.1% (52.0 to 76.7%) decline. There was a modest simultaneous increase in hanging suicides [20.0% (8.4 to 36.9%) increase] but the overall incidence of unnatural deaths fell from 14.0/100 000 to 10.5/100 000 [25.0% (18.1 to 33.0%) decline]. There were 35 071 (95% CI 25 959 to 45 666) fewer pesticide suicides in 2001 to 2014 compared with the number predicted based on trends between 1996 to 2000. This reduction in rate of pesticide suicides occurred despite increased pesticide use and no change in admissions for pesticide poisoning, with no apparent influence on agricultural output.

Conclusions

Strengthening pesticide regulation and banning WHO Class I toxicity HHPs in Bangladesh were associated with major reductions in deaths and hospital mortality, without any apparent effect on agricultural output. Our data indicate that removing HHPs from agriculture can rapidly reduce suicides without imposing substantial agricultural costs.

Historical trends in suicide risk for the residents of mainland China: APC modeling of the archived national suicide mortality rates during 1987-2012

PURPOSE

Distinctive and dramatic changes in the history of China with a rapid suicide decline in recent years present an opportunity to investigate the risk of suicide. In this study, we investigated suicide risk with a historical perspective with archived data to inform suicide research and prevention policies and strategies.

METHOD

Documented age-specific suicide mortality rates in 1987-2012 were decomposed into age, period, and cohort effect using APC-modeling method and intrinsic estimator (IE) technique. The estimated effects were further analyzed by numerical differentiation.

RESULTS

The data satisfactorily fit the constructed APC models. Cohort effect indicated that suicide risk in China fluctuated at very high levels during 1903-1967, followed by a sharp decline during 1968-1977, and reached the lowest level in 1983-1987 before increased again. Period effect confirmed the declining trend since 1987. Three sunny cohorts with reduced suicide risk and four cloudy cohorts with increased risk were, respectively, associated with significant cultural, social, political, and economic events in China since the 1900s.

CONCLUSIONS

The mega trends in the suicide risk at the population level are closely related to significant historical events in China. Suicide is anticipated to increase because of the growing risk for the young cohorts (particularly young females) as the country further develops. Study findings suggest the significance of national strategies for suicide prevention and control, including maintenance of social harmony and stability, provision of more opportunities for development, enhancement of social integration, and restriction of suicide facilitating factors.

Socio-demographic and economics factors associated with suicide mortality in Iran, 2001-2010: application of a decomposition model

BACKGROUND

Suicide is a major global health problem, especially among youth. Suicide is known to be associated with a variety of social, economic, political and religious factors, vary across geographical and cultural regions. The current study aimed to investigate the effects of socioeconomic factors on suicide mortality rate across different regions in Iran.

METHODS

The data on distribution of population and socio-economic factors (such as unemployment rate, divorce rate, urbanization rate, average household expenditure etc.) at province level were obtained from the Statistical Centre of Iran and the National Organization for Civil Registration. The data on the annual number of deaths caused by suicide in each province was extracted from the published reports of the Iranian Forensic Medicine Organization. We used a decomposition model to distinguish between spatial and temporal variation in suicide mortality.

RESULTS

The average rate of suicide mortality was 5.5 per 100,000 population over the study period. Across the provinces (spatial variation), suicide mortality rate was positively associated with household expenditure and the proportion of people aged 15-24 and older than 65 years and was negatively associated with the proportion of literate people. Within the provinces (temporal variation), higher divorce rate was associated with higher suicide mortality. By excluding the outlier provinces, the results showed that in addition to the proportion of people aged 15-24 and older than 65, divorce and unemployment rates were also significant predictors of spatial variation in suicide mortality while divorce rate was associated with higher suicide mortality within provinces.

CONCLUSION

The findings indicate that both spatial and temporal variations in suicide mortality rates across the provinces and over time are determined by a number of socio-economic factors. The study provides information that can be of importance in developing preventive strategies.

A social change perspective on injury prevention in China

INTRODUCTION

China has undergone massive social change over the past four decades. Since national estimates became available in 1987, the overall fatal injury rate has decreased. This paper investigates targeted interventions and sociodemographic factors that may have contributed to fatal injury rate changes particularly for road traffic fatality (RTF), suicide and drowning.

AIMS

(1) To review the recent epidemiology of injury in China.(2)To investigate factors influencing trends in overall and specific cause injury mortality rates.

METHODS

Published injury mortality statistics and related literature were reviewed. Factors potentially influencing trends were investigated in the context of rapid development based on literature reviews of targeted interventions, macrolevel and microlevel contextual factors and changes specific to RTF, suicide and drowning.

RESULTS

Overall estimated national injury mortality rates in China decreased between 1987 and 2015, despite a rapid rise in RTF. Suicide and drowning rates decreased significantly and falls displaced drowning among the leading causes. The higher female to male suicide ratio reversed. Differences were observed in frequencies and proportions of deaths by major cause by age group and over time.

DISCUSSION

Economic and structural development and related social change in this period include: urbanisation, changes in demographics, life choices (eg, internal migration), education, poverty alleviation, health insurance and relevant regulations/legislation. These factors potentially explain much of the change in fatal injury rates in China. Data limitations persist. Increased investment in data and research would provide realistic opportunities for accelerated progress in implementing effective targeted interventions to further reduce China's injury burden.

Burden of suicide in Poland in 2012: how could it be measured and how big is it?

OBJECTIVES

The aim of our study was to estimate the health-related and economic burden of suicide in Poland in 2012 and to demonstrate the effects of using different assumptions on the disease burden estimation.

METHODS

Years of life lost (YLL) were calculated by multiplying the number of deaths by the remaining life expectancy. Local expected YLL (LEYLL) and standard expected YLL (SEYLL) were computed using Polish life expectancy tables and WHO standards, respectively. In the base case analysis LEYLL and SEYLL were computed with 3.5 and 0% discount rates, respectively, and no age-weighting. Premature mortality costs were calculated using a human capital approach, with discounting at 5%, and are reported in Polish zloty (PLN) (1 euro = 4.3 PLN). The impact of applying different assumptions on base-case estimates was tested in sensitivity analyses.

RESULTS

The total LEYLLs and SEYLLs due to suicide were 109,338 and 279,425, respectively, with 88% attributable to male deaths. The cost of male premature mortality (2,808,854,532 PLN) was substantially higher than for females (177,852,804 PLN). Discounting and age-weighting have a large effect on the base case estimates of LEYLLs. The greatest impact on the estimates of suicide-related premature mortality costs was due to the value of the discount rate.

CONCLUSIONS

Our findings provide quantitative evidence on the burden of suicide. In our opinion each of the demonstrated methods brings something valuable to the evaluation of the impact of suicide on a given population, but LEYLLs and premature mortality costs estimated according to national guidelines have the potential to be useful for local public health policymakers.

Sharply Reduced but Still Heavy Self-Harm Burdens in Hubei Province, China, 1990-2015

The aims of this study were to describe fatal and non-fatal self-harm burdens, as well as burdens from the main preventable risk factors, and to investigate the different suicide methods in Hubei province in central China utilizing data from both Global Burden of Disease Study 2015 and Hubei Disease Surveillance Points system. All self-harm burdens including mortality, years of life lost (YLLs), prevalence, years lived with disability (YLDs), and disability adjusted life-years (DALYs) consistently demonstrated downward trends in Hubei from 1990 to 2015, with a bigger decline gap observed among females and narrower decreasing amplitudes among the elderly. Hubei experienced much higher age-standardized rates for self-harm mortality (22.0 per 100,000), YLLs (560.1 per 100,000) and DALYs (563.9 per 100,000) than the national (9.0, 292.3 and 295.0 per 100,000 respectively) and global levels (11.5, 453.3 and 457.9 per 100,000 respectively) in 2015. Self-harm burdens have begun shifting from females to males and the elderly suffered more self-harm burdens than other age groups. Alcohol use accounted for 20.9% of all self-harm DALYs for males, whereas intimate partner violence accounted for 24.4% of all self-harm DALYs for females. Poisoning, mainly pesticide self-poisoning, was still the most common method of suicide. Effective interventions by multi-sectoral collaboration are urgently needed to reduce the alarmingly heavy self-harm burdens in Hubei.

Stroke Mortality Attributable to Ambient Particulate Matter Pollution from 1990 to 2015 in China: An Age-Period-Cohort and Spatial Autocorrelation Analysis

In this study, we analyzed the temporal and spatial variations of stroke mortality attributable to ambient particulate matter pollution (stroke mortality-PM_2.5) in China from 1990 to 2015. Data were collected from the Global Burden of Disease (GBD) 2015 study and analyzed by an age-period-cohort model (APC) with an intrinsic estimator (IE) algorithm, as well as spatial autocorrelation based on the Geographic Information System. Based on APC analysis with the IE method, stroke mortality-PM_2.5 increased exponentially with age, its relative risk reaching 42.85 (95% CI: 28.79, 63.43) in the 75–79 age group. The period effects showed a reversed V-shape and its highest relative risk was 1.22 (95% CI: 1.15, 1.27) in 2005. The cohort effects decreased monotonically from 1915–1919 to 1990–1994. The change rate fluctuated from 1920–1924 to 1990–1994, including three accelerating and three decelerating decreases. There was a positive spatial autocorrelation in stroke mortality-PM_2.5 from 1990 to 2015. Hot-spots moved from the northeastern areas to the middle and southwestern areas, whereas cold-spots lay mostly in coastal provinces. Besides the aging process in recent years, stroke mortality-PM_2.5 had significantly declined from 2005 to 2015 due to socio-economic and healthcare development. Stroke mortality-PM_2.5 varied substantially among different regions, and cost-effective prevention and control should be implemented more in the middle and southwestern areas of China.