The total number of global deaths from suicide increased annually from 762,000 to 817,000 between the years 1990 and 2016, a new study finds.
However, after making adjustments for asymmetric age group population growth across the 27-year time span, the researchers found that the suicide fatality rate actually decreased by nearly a third during that time.
The international team of researchers, led by Dr. Mohsen Naghavi of the Institute for Health Metrics and Evaluation at the University of Washington in Seattle, used data from their 2016 Global Burden of Disease Study to describe patterns of suicide over a nearly three-decade period ending in 2016. Their findings were published Wednesday in the journal The BMJ.
Suicide rates between the sexes
Previous research has indicated that men, younger adults and older adults have higher rates of suicide than women and middle-aged adults. The new report finds that once again, suicide rates were higher for men than for women across regions, countries and age groups, except for the 15-to-19 age group.
"In this age group women had consistently higher rates of suicide mortality," Naghavi and his co-authors wrote, though the gap narrowed over time.
At the national level, rates of suicide mortality for women were lower than those for men in all countries except Liberia. Worldwide, the rates were about 16 deaths per 100,000 men and 7 deaths per 100,000 women in 2016. Women around the globe also experienced a greater decrease in suicide rate (49%) compared with men (nearly 24%) over the study period.
Suicide rates by region
Still, the authors found that drivers of suicide fatalities varied by region. "In most parts of the world, suicide deaths are higher among men than women, although this ratio is much lower for countries across a belt that extends from southern India to China, including some islands in the Pacific ocean," they wrote.
In 2016, among countries with populations greater than 1 million, adjusted mortality rates from suicide were highest in Lesotho (39 deaths per 100,000), Lithuania (31 per 100,000), Russia (just under 31 per 100,000) and Zimbabwe (almost 28 per 100,000). Suicide rates were lowest in Lebanon (about 2 deaths per 100,000), Syria (2.5 per 100,000), Gaza and the West Bank and Kuwait (2.7 per 100,000) and Jamaica (2.9 per 100,000).
Overall, suicide was in the top 10 leading causes of death across Eastern Europe, Central Europe, high-income countries within Asia Pacific, Australasia and high-income countries in North America. Within regions and countries, though, suicide rates soared among people with lower social and economic status.
The authors also noted that "in Western countries, there is a strong relation between mental illness and suicide, however, in Asia, this relation is much less pronounced."
Suicide rates within nations
Individual nations saw decreases in suicide deaths. Across the study period, the largest decreases were seen in China (64.1%) Denmark (60%), the Philippines (58.1%), Singapore (50.6%) and Switzerland (50.3%), as well as in the smaller countries of the Maldives (59.1%) and Seychelles (56.1%).
"The changes observed in China have been attributed to economic growth, urbanisation, improved standards of living, and better access to medical care in rural areas," the authors wrote. At the opposite end of the spectrum, the suicide rate in Zimbabwe rose 96%, from about 14 per 100,000 to nearly 28 across the study period, though this change could not be explained.
Dr. Sandro Galea, dean and Robert A. Knox Professor at the Boston University School of Public Health, said the report had three "real findings," of which the first is that "the suicide rate is going down overall." This report is the first "in a while" to have such findings, he said.
Second, said Galea, who was not involved in the research, the consequences of suicide are "huge worldwide," and third, "there are enormous differences in suicide rates worldwide, which are quite extraordinary."
Suicide data is difficult to collect
"I think this conforms to impressions I've had," Galea said of the overall findings. "It's very helpful to have this cross-national comparison." He noted challenges in collecting data with uneven health reporting accuracy across nations but said the Institute for Health Metrics and Evaluation is the "gold standard" when it comes to gathering and analyzing global data of this type.
Ellicott C. Matthay, a postdoctoral scholar in the Department of Epidemiology and Biostatistics at the University of California, San Francisco, also noted the difficulties when reporting global health. In an editorial published alongside the study, he wrote that the results could "reflect data problems such as under-reporting, differential reporting, or misclassification of cause of death owing to the sensitive and illegal nature of suicide in many countries."
Although the findings should be "interpreted with some caution," the new report provides a basis for a variety of follow-up studies, he said. For example, researchers might try to identify the drivers of the spiking suicide rate in Zimbabwe.
"Results could prove useful to governments, international agencies, donors, civic organizations, physicians, and the public to identify the places and groups at highest risk of self harm and to set priorities for interventions," Matthay wrote.
The World Health Organization's Comprehensive Mental Health Action Plan 2013-2020 aims to reduce suicide mortality by a third between 2015 and 2030.
Navgahi and his co-authors have this goal foremost in their thoughts. They conclude, "Although the decrease in suicide mortality has been substantial during the period 1990 to 2016, if current trends continue, only 3% of 118 countries will attain the Sustainable Development Goals target to reduce suicide mortality by one third between 2015 and 2030."