Temporal trend of mortality by suicide among adults in Brazil: 2000 to 2015

Abstract Objective To analyze temporal trends of mortality due to suicide among adults in Brazil, by macroregion and gender, from 2000 to 2015. Methods A retrospective study of temporal trends in suicide mortality rates in adults aged 20 to 64 years, by macroregion and gender, from 2000 to 2015. Data from the Brazilian Mortality Database (SIM) and from the Brazilian Institute of Geography and Statistics (IBGE) were used. The mortality rate trends analysis was performed using simple linear regression, with Stata 14 software. Results There was an upward trend in mortality due to intentionally inflicted self-harm in the Brazilian adult population in the North, Northeast, and Southeast regions for both genders (p<0.001), with predominance in the male population in these three regions and throughout the country (p<0.001). A downward trend was observed in the South and Midwest (p=0.003 and p=0.040). Conclusion Mortality due to intentionally inflicted self-harm has increased in Brazil, but has undergone important variations in different parts of the country. Even a regional analysis is insufficient to achieve a thorough evaluation of these contrasts because of the country’s continental proportions and data collection biases. Further studies focused on this topic are required.


Introduction
The World Health Organization (WHO) considers suicide a complex phenomenon, with avoidable and multifactorial causes and which affects not only the individual, but also his/her family and the whole community of which he/she is a member. It is the second cause of death in the population of adults aged between 15 and 29 years worldwide and accounts for about 800,000 deaths a year (the equivalent to about 1 person every 40 seconds). 1 This number is known to be underestimated due to biases in data collection, which is not performed in certain regions and varies over the years, and also to the pervasive confounding factor of suicide notified as accident or death of indeterminate cause. 1 In Brazil, suicide mortality is approximately 11,000 people a year and is the fourth cause of death in the general population (in the age range from 15 to 29 years it is the third cause among men and the eighth among women). 2 It has been estimated that the average suicide mortality rate in the country from 1980 to 2000 was 3 to 4 out of every 100,000 inhabitants, which is considered low compared with international standards. In the 1990s, the annual average rose to levels between 5 and 15 per 100,000 inhabitants, which is classified as medium incidence. These numbers change significantly by region, microregion, and under different socioeconomic and climatic conditions. 3 However, evidence indicates that suicide rates continue to increase in Brazil, especially among young men and middle-aged women. 4 In the last century, suicide was recognized as a subject of interest and a public health problem on a global scale. 5 The number of studies on the subject increased as well as researchers' interest in carrying them out, although the number remains low, with flaws affecting data collection, and the financial resources available are insufficient. The main risk factors for suicide already identified in other studies are: mental diseases and disorders; use of certain medications, drugs and alcohol, exposure to pesticides; terminal and degenerative diseases; and influence of media. [4][5][6][7] Additionally, Brazil has one of the world's highest levels of income inequality, which has a direct impact on population health and on causes of death. 8 There are several studies in the literature describing causes, "suicidogenic" factors, and major influences, both in Brazil and in other parts of the world. [9][10][11][12][13] In these studies, the main objects of study are risk and protection factors and the characteristics of the populations involved in the act. However, there is a lack of studies evaluating temporal trends in Brazil by macroregions or microregions, mainly more recent ones, or their associations with local conditions. Suicide itself is a sensitive topic, and collection and analysis of data relating to it is difficult and controversial.
Furthermore, setting parameters for a country with such large dimensions as Brazil is a challenge.
Considering the above, this study aims to analyze temporal trends in mortality due to suicide in adults in Brazil, by macroregion and gender, from 2000 to 2015.

Methods
This is a retrospective study of temporal trends in suicide mortality rates in the adult Brazilian population aged between 20 and 64 years, by gender and macroregions, from 2000 to 2015.
In this study, suicides were defined as deaths caused by intentionally inflicted self-harm, codes X60 to X84 Rates were calculated per 100,000 inhabitants.
The analysis of mortality rate trends was conducted using simple linear regression with STATA 14 software.
This model was chosen for its straightforward preparation and interpretation and its statistical power. The death rate from intentionally inflicted self-harm was defined as the dependent variable and the years analyzed in the study (2000)(2001)(2002)(2003)(2004)(2005)(2006)(2007)(2008)(2009)(2010)(2011)(2012)(2013)(2014)(2015) were defined as the independent variable. The linear trend was only considered statistically significant when its probability of occurrence was equal to or lower than 0.05, that is, p ≤ 5%.
This study analyzed aggregated public data without identifying the people involved and approval by a Human Research Ethics Committees (HREC) was therefore not required. This study is in compliance with CNS resolution 510, of April 7, 2016.

Results
From 2000 to 2015, 117,322 adult deaths from intentionally inflicted self-harm occurred in Brazil, which corresponds to 1.72% of all deaths in this period. This sample was 79.7% male and the ratio of about 5 male deaths to 1 female death holds not only in the overall sum of obituaries, but also in the annual distribution in almost all of the years analyzed ( Table 1).
The method most frequently used by the adult population of both genders was hanging or strangulation (X70), which accounted for 59.5% of the total mortality, followed by intentional firearm injury (X71 to X74), used by 8.6%, and self-poisoning using pesticides (X68) and other chemicals or unspecified harmful substances (X69). After hanging or strangulation, the male population preferred firearms (X72 to X74) and pesticides (X 68), while the female population's second option was pesticides (X 68), followed by other chemicals and harmful substances (X69).
In 2000, there were 5.84 suicide deaths for each 100,000 inhabitants of both genders in Brazil. In 2015, this rate was 7.23. This represents a 19% increase in the incidence of self-harm deaths over the period analyzed.
The magnitudes of the male rates are remarkable for all years and are from 3 to 5 times greater than the female rates ( Table 2). There was a tendency for suicide mortality to increase in each gender separately and for both genders taken together in the Northeast and Southeast regions and

Discussion
The absolute numbers of suicides increased over the years analyzed, following the gradual increase in the Brazilian population. The percentage of 1.72% of deaths found is slightly higher than the worldwide percentage The same bulletin reports that, although the male population accounts for 80% of accomplished deaths by suicide, women try to commit suicide more frequently (69%) and tend to repeat the attempts 6% more than men. The population of suicide attempters analyzed in the bulletin preferred intoxication by drugs or other chemicals and harmful substances. The difference between attempts and consummated acts in the population can be related to more violent methods preferred by men (firearms, for example), rather than drugs or other substances, which are the first choice of women who attempt suicide and tend to be less lethal. 2 The North and Northeast regions showed significant upward trends. The trend in the Northeast region was the highest percentage increase among all the regions studied, although the rates in the North and Northeast remain the two lowest rates per 100,000 inhabitants in the study. It is of note that in poorly assisted regions, there is little or no incentive for the municipality/State to refine collection of data on mortality, since, at first sight, to do so would make the municipality or region in question have worse outcomes. Moreover, one must also consider the smaller scope of the healthcare network and the work of Psychosocial Care Centers (PCC) in the North region, which has the worst coverage of all 5 regions. 16 Furthermore, certain factors are considered "suicidogenic", including local environmental and socioeconomic ills, such as drought, famine, rising violence in areas of vulnerability associated with use of drugs and alcohol, poor health conditions with consequent increase in infant and maternal mortality, incidence of psychiatric disorders without treatment, and labor exploitation -especially in rural areas. 5,11 There is consensus that the Human Development Index (HDI) is associated with violence -self-directed or otherwise.

Conclusion
Mortality from intentionally inflicted self-harm increased in Brazil over recent years, especially in the male population from the North, Northeast, and Southeast regions. In the South and Midwest regions, there were significant downward trends in the male population and in the population as a whole (both sexes together). It is important to highlight that the national mortality coefficients hide very significant regional variations and are difficult to measure and also that Brazil is a country of continental proportions.
Even regional analyses have significant intra-regional variations and further studies are needed to enable identification of more accurate associations (such as studies with age stratification). Economic, social, and cultural parameters are strongly linked to these differences and may be factors of increased risk or protection.

Disclosure
No conflicts of interest declared concerning the publication of this article.