The overall global number of deaths by suicide increased by almost 20,000 during the past 30 years, new research shows.
The increase occurred despite a significant decrease in age-specific suicide rates from 1990 through 2019, according to data from the Global Burden of Disease Study 2019.
Population growth, population aging, and changes in population age structure may explain the increase in number of suicide deaths, the investigators note.
“As suicide rates are highest among the elderly (70 years or above) for both genders in almost all regions of the world, the rapidly aging population globally will pose huge challenges for the reduction in the number of suicide deaths in the future,” write the researchers, led by Paul Siu Fai Yip, PhD, of the HKJC Center for Suicide Research and Prevention, University of Hong Kong, China.
The findings were published online Aug. 16 in Injury Prevention.
Global public health concern
Around the world, approximately 800,000 individuals die by suicide each year, while many others attempt suicide. Yet suicide has not received the same level of attention as other global public health concerns, such as HIV/AIDS and cancer, the investigators write.
They examined data from the Global Burden of Disease Study 2019 to assess how demographic and epidemiologic factors contributed to the number of suicide deaths during the past 30 years.
The researchers also analyzed relationships between population growth, population age structure, income level, and gender- and age-specific suicide rates.
The Global Burden of Disease Study 2019 includes information from 204 countries about 369 diseases and injuries by age and gender. The dataset also includes population estimates for each year by location, age group, and gender.
In their analysis, the investigators looked at changes in suicide rates and the number of suicide deaths from 1990 to 2019 by gender and age group in the four income level regions defined by the World Bank. These categories include low-income, lower-middle–income, upper-middle–income, and high-income regions.
Number of deaths versus suicide rates
The number of deaths was 738,799 in 1990 and 758,696 in 2019.
The largest increase in deaths occurred in the lower-middle–income region, where the number of suicide deaths increased by 72,550 (from 232,340 to 304,890).
Population growth (300,942; 1,512.5%) was the major contributor to the overall increase in total number of suicide deaths. The second largest contributor was population age structure (189,512; 952.4%).
However, the effects of these factors were offset to a large extent by the effect of reduction in overall suicide rates (−470,556; −2,364.9%).
Interestingly, the overall suicide rate per 100,000 population decreased from 13.8 in 1990 to 9.8 in 2019.
The upper-middle–income region had the largest decline (−6.25 per 100,000), and the high-income region had the smallest decline (−1.77 per 100,000). Suicide rates also decreased in lower-middle–income (−2.51 per 100,000) and low-income regions (−1.96 per 100,000).
Reasons for the declines across all regions “have yet to be determined,” write the investigators. International efforts coordinated by the United Nations and World Health Organization likely contributed to these declines, they add.