Temporal Trend in Suicide Mortality for Chinese Adolescents, 2008 to 2021

Abstract

This study aims to evaluate the temporal trend in suicide mortality for Chinese adolescents aged 10 to 19 years from 2008 to 2021.

Suicide is the third leading cause of death among adolescents aged 15 to 19 years¹ and approximately 88% of adolescents who died by suicide in 2019 were from developing countries.² As the world’s biggest developing country, China has taken a series of strategies to prevent suicide and suicide mortality has dropped significantly among young people aged 15 to 24 years from 2002 to 2015.³ The present study aimed to evaluate the temporal trend in suicide mortality for Chinese adolescents aged 10 to 19 years from 2008 to 2021.

Methods

Using data from the data set of National Mortality Surveillance in China (eAppendix 1 in Supplement 1),⁴ we designed a population-based longitudinal study to assess temporal trends in suicide mortality by sex (female/male), areas of residence (rural/urban), geographic regions (central, eastern, and western), and age groups (10 to 14 years; 15 to 19 years) from 2008 to 2021. Age-adjusted suicide mortality rates were calculated using the 2010 population of China as the reference. Joinpoint regression fitting was performed on the natural logarithm of suicide mortality rate in different segments (eAppendix 2 in Supplement 1) and then annual percentage change (APC) and average annual percentage change were obtained. A Joinpoint regression model was performed using Joinpoint Regression program 4.9.1.0.⁵ Since all data were directly derived from the public data set and did not include any personal identifying information, ethical approval and informed consent were not required, according to the Ethical Review Measures for Biomedical Research Involving Human Subjects in China. This study followed STROBE reporting guidelines.

Results

From 2008 through 2021, the data set of National Mortality Surveillance in China reported 5738 suicide deaths among adolescents (Table). Among them, 3281 were male (57.18%), 4231 lived in rural areas (73.74%), and 1675 lived in eastern China (29.19%). The age-adjusted suicide mortality rate significantly decreased from 2.16 to 1.59 per 100 000 people from 2008 to 2017 (APC = −3.38%) and then rapidly increased from 1.59 to 2.83 per 100 000 people from 2017 to 2021 (APC = 15.56%). Similar trends were found in stratification by sex, area, and region (Figure).

Table. Number, Percentage, and Suicide Mortality of Chinese Adolescents Aged 10 to 19 Years, 2008 to 2021.

Characteristic	2008-2021 No. (%)	Age-adjusted suicide mortality (per 100 000 people)a			2008-2021 AAPC (95% CI)	P value
		2008	2017	2021
Total	5738 (100)	2.16	1.59	2.83	2.09 (0.19-4.04)	.03
Sex
Female	2457 (42.82)	2.38	1.25	2.84	1.37 (−1.85 to 4.69)	.41
Male	3281 (57.18)	2.00	1.91	2.82	2.69 (1.11-4.29)	.001
Residenceb
Rural	4231 (73.74)	2.41	1.84	2.92	1.48 (−1.11 to 4.12)	.27
Urban	1507 (26.26)	1.47	1.28	2.85	5.23 (1.96-8.61)	.002
Regionc
Central	1864 (32.49)	1.77	1.61	3.03	4.23 (2.00-6.50)	<.001
Eastern	1675 (29.19)	1.73	1.31	2.66	3.35 (−2.32 to 9.35)	.25
Western	2199 (38.32)	3.14	1.95	2.98	−0.40 (−2.69 to 1.94)	.73
Age, yd
10-14	1604 (27.95)	1.01	0.91	1.76	4.40 (0.08-8.90)	<.05
15-19	4134 (72.05)	3.04	2.09	3.63	1.36 (−0.79 to 3.56)	.22

Abbreviation: AAPC, average annual percentage change.

^a Age-adjusted suicide mortality rates were calculated using the 2010 population of China as the reference.

^b The data set of National Mortality Surveillance in China classified all counties (including county-level cities) as rural areas and all districts of a city as urban areas.

^c The data set of National Mortality Surveillance in China divided 31 provincial administrative regions (provinces, municipalities, and autonomous regions) in mainland China into eastern regions (Beijing, Tianjin, Hebei, Liaoning, Shanghai, Jiangsu, Zhejiang, Fujian, Shandong, Guangdong, and Hainan), central regions (Shanxi, Jilin, Heilongjiang, Anhui, Jiangxi, Henan, Hubei, and Hunan), and western regions (Nei Mongol, Guangxi, Chongqing, Sichuan, Guizhou, Yunnan, Tibet, Shaanxi, Gansu, Qinghai, Ningxia, and Xinjiang).

^d Crude suicide mortality rate per 100 000 individuals.

Figure. Temporal Trend in Suicide Mortality for Chinese Adolescents Aged 10 to 19 Years, 2008-2021.

APC indicates annual percent change.

^aStatistical significance P value of <.05.

Compared with males, females had lower age-adjusted suicide mortality since 2011 (Figure, A). Adolescents living in urban areas consistently had lower suicide mortality than those living in rural areas across the study period (Figure, B). However, adolescents living in urban areas had a more rapid rise in suicide mortality in recent years compared with those living in rural areas (urban, APC 2017-2021 = 22.08%; rural, APC 2018-2021 = 17.76%). Adolescents living in eastern regions tended to have lower age-adjusted suicide mortality than those living in other 2 regions across the study period (Figure, C).

Adolescents aged 15 to 19 years had higher suicide mortality than those aged 10 to 14 years throughout the study period (Figure, D). From 2008 to 2017, suicide mortality significantly decreased in adolescents aged 15 to 19 years (APC 2008-2017 = −4.08%), while it remained stable in adolescents aged 10 to 14 years. After 2017, suicide mortality significantly increased in all adolescents (10 to 14 years, APC 2017-2021 = 17.88%; 15 to 19 years, APC 2017-2021 = 14.77%). The average annual percentage change of suicide mortality was 4.40% in adolescents aged 10 to 14 years.

Discussion

Using nationally representative data in China, we updated the temporal trend in suicide mortality among adolescents aged 10 to 19 years and found a U-shaped trend between 2008 and 2021. The downward trend in suicide mortality among adolescents from 2008 through 2017 was consistent with previous studies,³ while the rising trend during 2017 through 2021 was initially noted. Adolescence is a susceptible period to life stress events, like family conflicts and academic stressors.⁶ Because of the significant increase in suicide mortality in recent years, there is an urgent need to strengthen awareness of mental health issues and identify early signs of suicidal ideation to prevent suicide for Chinese adolescents. The major limitation was lacking data on causes of suicide, and thus, we failed to analyze temporal trends in suicide mortality for different causes and provide precise strategies to prevent suicide.

Supplement 1.

eAppendix 1. Description of data

eAppendix 2. Description of statistical analyses

Supplement 2.

Data sharing statement