Background
Suicide is a major contributor to premature mortality worldwide and is among the leading causes of death in the Western Pacific Region [
1]. Approximately 32% of the world's suicides occur in the region, and its annual incidence of 19.3 per 100,000 is 30% higher than the global average [
2]. While acknowledged as an important and neglected health issue, it remains a low priority in most Western Pacific countries due to competing health problems, stigma and poor understanding of the condition [
3].
The Philippines, with a population of approximately 90 million, is one of the most populous countries in the Western Pacific, yet very little is known about the epidemiology of suicide and suicidal behaviour in the country [
4]. The only predominantly Catholic country in Asia, it is an archipelago of 7,106 islands, with 66% of the population living in urban areas [
4‐
6]. Around 33% of the population are impoverished, in spite of reported economic growth in recent years [
5].
Official suicide rates are lower in the Philippines than in many other countries in the Western Pacific region [
7], although there is likely to be under-reporting because of its non-acceptance by the Catholic church and the associated disgrace and stigma to the family [
8]. As in other Catholic countries, a high proportion of suicide deaths are likely to be misclassified as injury of undetermined intent or accidents [
9]. A systematic analysis of the possible underreporting of suicides is important so its true incidence and trends can be estimated. To date, no studies of national trends in the incidence of suicide or the national epidemiology of suicidal behaviour have been undertaken using Philippine mortality data. Such an analysis is important both to provide a more complete picture of the size of the problem and to facilitate better informed decisions concerning priorities for prevention such as high risk age/sex groups and popular suicide methods that are potentially amenable to method-restriction policies.
Discussion
To the best of our knowledge, this is the first comprehensive summary of the epidemiology of suicidal behaviour in the Philippines. Whilst the incidence of suicide in the Philippines is low compared to other countries [
21,
22], it appears to have been increasing in recent years, particularly amongst males. Amongst females the highest rates are seen in 15-24 year olds. There is indirect evidence that suicide is under-reported in the Philippines.
The low rates of suicide in the Philippines in the early 1980s could reflect social cohesion during the turbulent Martial Law era and its aftermath [
23]. Reductions in suicide rates during periods of war and civil disturbance are well recognised [
24]. Recent increases in suicide might be explained by improved reporting and changing social attitudes. Up until 1983 suicides were barred from receiving religious burial rites in the Philippines. The 1983 revision of the Canon Law removed this prohibition [
25] and this change coincided with the increase in reported mortality rates. Similar trends and changing attitudes were observed in Ireland which is also predominantly Catholic [
26]. Rising trends in suicide in the Philippines are in keeping with the increases seen in a number of Asian countries - most notably Thailand, South Korea, Japan and Hong Kong [
22], in contrast many Western countries have experienced reductions in rates since the 1980s [
9,
27].
The Philippines is a predominantly Roman Catholic country and it is possible that reluctance to report deaths as suicide contribute to the low official rates. Nevertheless, the strong Roman Catholic culture could also contribute to preventing some suicides, due to the beliefs and social norms associated with Catholicism. Similar protective effects of Catholicism have been reported in a recent analysis of data from Switzerland [
28]. Likewise, predominantly Catholic countries in Europe such as Portugal, Spain and Italy have amongst the lowest suicide rates in that region.
More women than men attempt suicide in the Philippines, but as seen in most other countries case fatality is higher in males, in part due to males' preference for more violent/lethal methods of suicide. The male-to-female ratio for suicide (3.3:1) in the Philippines is higher than in China or India but comparable to that seen Thailand, Japan and New Zealand [
2]. The male: female ratio increased almost two fold between the mid-1980s to 2005. There is no clear explanation for this change, although it could be partly due to persisting poverty and income inequality, combined with increasing labour market competitiveness during this period, despite reported economic growth [
29,
30]. Other studies have shown that working age men may be more susceptible to suicide in times of economic difficulty than women, possibly due to higher societal pressures to succeed [
31].
Suicide attempts and mortality were generally higher in adolescents and young adults than in the older age groups, this contrasts with patterns seen in most countries where rates tend to increase with age [
32]. However similar high rates in young people have been reported in Pakistan and Thailand [
33,
34]. This could be due to increased vulnerability of young people to social stressors [
35]. Adolescence is a period of life changes and most teenagers struggle with issues such as independence and developing a sense of identity and a system of values and responsibilities. These struggles are manifest in the high incidence of non-fatal self-harm in this age group worldwide, but in most countries such attempts are generally of lower lethality than attempts made in older age groups, and so are not reflected in statistics for completed suicide. Reasons for this excess in young people in the Philippines require further investigation.
The increasing rates of suicide and accidental deaths and corresponding decrease in undetermined deaths are suggestive of some underreporting and misclassification. More studies, however, are needed to further evaluate possible underreporting. The small peak in the mid-1990s coincided with the passage of the Administrative Order 1, s. 1993, which defined and updates civil registry laws and guidelines [
36], this could have resulted in better suicide reporting, if only for a short period of time.
There is a dearth of detailed information on the incidence of suicide and suicide attempts in rural areas but the rate reported in one indigenous population in the 1990s is among the highest in the world (173 per 100,000) [
15]. High suicide rates have been reported among indigenous groups in other settings [
37]. Although of a larger magnitude, the difference in rates between the Kulbi people and the general population is similar to that observed between the Atayal people and the Taiwanese population [
37].
The most commonly used methods of suicide in the Philippines appear to be hanging, shooting and organophosphate poisoning. Although, the lack of method-specific suicide mortality data means that these observations are based on newspaper reports; such reporting is likely to be non-representative and restricted to the most newsworthy and overt suicides. Non-fatal self harm most often involved drugs such as isoniazid and paracetamol, which can be purchased without prescription and in unlimited amounts. Paracetamol is widely used as an analgesic and antipyretic drug, and high use of isoniazid reflects its availability due to the high prevalence of TB in the Philippines [
38], where it is known as a vitamin or medication for "weak lungs" (a local euphemism for TB) [
39].
The choice of method is greatly influenced by availability. In the Philippines, there is minimal regulation for the sale of over the counter drugs and organophosphate insecticides, although many toxic pesticides are banned in the country [
40]. Private possession of firearms is allowed conditional to acquisition of a license, which is not subject to background checks [
41,
42]; 'home-made' firearms are also in common use[
42].
Our study has some limitations, particularly the availability and reliability of routinely reported mortality data. Aside from the reluctance to report suicide deaths due to the stigma, inadequacies have also been noted in death registration practices, and incompleteness and errors in entries for the cause of death in official records[
13,
43]. Even in medically attended deaths, certification is generally based on the clinical symptoms rather than results of autopsy. Although guidelines for death certificate completion exist, these are often not followed [
44].
The profile of people who made suicide attempts was derived from hospital-based studies in selected, mainly urban, areas; patterns may differ in more rural locations. Suicide patterns and beliefs could be different for people in rural areas and for cultural minorities, as seen in the study of the Kulbi people [
15]. Furthermore these studies covered different time periods and so the patterns of medicines and poisons taken in suicide attempts may be non-comparable if these have changed over time.
Competing interests
The authors declare that they have no competing interests. DG is an NIHR Senior Investigator.
Authors' contributions
MTR conducted data synthesis and analysis and drafted the manuscript, MAL supervised data collection and literature review, DG supervised data synthesis and analysis and the drafting of the manuscript. All authors contributed to the conceptualization of the research, and reviewed and approved the manuscript.