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Suicide around public holidays Emma Barker, John O'Gorman and Diego De Leo Australas Psychiatry published online 4 February 2014 DOI: 10.1177/1039856213519293 The online version of this article can be found at: http://apy.sagepub.com/content/early/2014/02/04/1039856213519293 A more recent version of this article was published on - Apr 8, 2014
Published by: http://www.sagepublications.com
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The Royal Australian and New Zealand College of Psychiatrists
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research-article2014
APY0010.1177/1039856213519293Australasian PsychiatryBarker et al.
AP
Suicide around public holidays Emma Barker Australian Institute for Suicide Research and Prevention, Griffith University,
Australasian Psychiatry 1–5 © The Royal Australian and New Zealand College of Psychiatrists 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav DOI: 10.1177/1039856213519293 apy.sagepub.com
Brisbane, QLD, Australia
John O’Gorman Australian Institute for Suicide Research and Prevention, Griffith University, Brisbane, QLD, Australia Diego De Leo Australian Institute for Suicide Research and Prevention, Griffith University, Brisbane, QLD, Australia
Abstract Objective: To examine the frequency of suicides on holidays and special days of the year, specifically in Queensland, Australia. Methods: We analysed data from the Queensland Suicide Register between 1990 and 2009. The days examined were: Easter, Christmas, New Year, Valentine’s Day and Anzac Day. We compared suicide cases on these days with the average counts for periods before and after the days. Results: There was a statistically significant increase in suicides on Christmas Eve and on New Year’s Day. Our results are discussed in light of trends reported in the literature. Conclusion: The beginning and end of the festive season are times when special attention is warranted for those with a heightened risk of suicide. Keywords: Australia, festive season, holiday, Queensland, risk, suicide
R
esearch suggests that rates of suicide do not remain consistent throughout the year; rather there appear to be temporal patterns of suicide, influenced by the season1,2 and day of the week.3,4 Another time when suicidal behaviour may fluctuate is the period surrounding significant public holidays.5 Studies indicate that the rates of suicide may increase in the days after Christmas6,7 and during the New Year period.6,8,9 This effect does not appear to be restricted to the Christmas/New Year period, as significant increases in suicides are noted around Easter,10 in particular the Saturday after Good Friday.6 Public holidays do not necessarily mean an increase in suicide, however, as rates decrease on Christmas Day itself6 and other significant days during the Easter period, including Easter Sunday and Monday.6,9 Bridges11 supports the finding of a decrease in suicide on the actual day of the holiday in the US, finding for all holidays (except for New Year’s Day) that the average suicide rate declined from 33.7 to 31.5 per 100 million persons, per day.11 Studies including Emergency Department presentations for non-fatal suicidal behaviour have found similar results to those focusing on fatal suicidal behaviour. Jessen et al.5 find fewer suicide attempts than expected before Christmas, but more attempts after Christmas (a 39% increase) and on New Year’s Day.5 However, these
results were not as consistent as with fatal suicidal behaviour: research finds a decrease in admissions on Christmas day, but no significant increase in the following 11 days.12 Valentine’s Day appears to be the only special day, other than New Year’s Day, that sees an increase in suicidal behaviour on the holiday itself.13 There are two main hypotheses in the literature that may offer some explanation for the fluctuations in suicide around public holidays. The theory of the ‘broken promise effect’ presents the idea that certain days of the year promise more than they can deliver, leaving individuals feeling deflated afterwards and increasing the risk for suicide.14 The trends reported in the current literature for special days and public holidays appear to be consistent with research on birthdays15 and seasons,16 which support the idea of a broken promise effect during these times. Holiday periods, anticipated to be an enjoyable time, may coincide with extra life stressors, including family conflict, alcohol use and increased spending6 that may exacerbate loneliness in those who are not able to share the holiday time with their families. Corresponding author: Diego De Leo, Australian Institute for Suicide Research and Prevention (AISRAP), Griffith University, 176 Messines Ridge Road, Brisbane, QLD 4122, Australia. Email: [email protected]
1 Downloaded from apy.sagepub.com at University of Newcastle on September 5, 2014
Australasian Psychiatry
A second possible reason for the decrease in suicide witnessed on the holiday itself, and the increase after the holiday, involves the prospect of returning to work after the holiday. This is consistent with previous findings that suicide rates are highest at the beginning of the work week, particularly Mondays, and decline as the week progresses3,4; and indications that New Year’s Day, which generally signifies the end of the holiday season and beginning of a new working year, is associated with an increase in suicides. This is also supported by the fact that research in this area involving psychiatric inpatients fails to find such strong effects.17,18 The exception is Valentine’s Day, which does not involve a day off work, with suicides around this time being more likely to be influenced by the romantic aspects of the day.13
accurate date of death available for analysis. The total number of cases meeting these criteria was 10,511. We excluded 46 cases because the date of death could not be ascertained. The number of days between the date of death for each individual and each of the seven significant days under investigation was calculated; and we recorded the number of suicide deaths occurring the day before, on and after that public holiday or special day. Six suicide cases occurred during the New Year’s period in 1990. These cases were excluded from the final analysis, because there was no December 1989 data available for comparison. Similarly, we excluded another five cases because they occurred on or around Christmas 2009, and no January 2010 data were available for comparison at the time we wrote this article.
The aim of the current study was to evaluate the fluctuation of suicide around major public holidays and significant days in Australia. The days selected were the days of Easter, Christmas Day, New Year and Valentine’s Day (which was studied previously) and Anzac Day (25 April). The latter is a public holiday and a day of special significance to the Australian community, which recognises the contribution of those who lost their lives in the defence of their country.
To provide a basis for comparison, we made counts of suicide for the days corresponding to the holidays and special days, and 1 week before and 1 week after Anzac Day and Valentine’s Day. For Easter, we made counts of suicides for the 6 days in March before the Easter period and for the 6 days in April/May after the Easter period. In the case of Christmas and the New Year (which are separated by 1 week), the comparison period for after Christmas was displaced to the week after the New Year; and the comparison period before New Year was displaced to the week before Christmas. This provided an observation window before and after the period of interest, to establish the average number of suicides about that time. We based the estimate on a period ‘about that time’, because suicide is known to show seasonal effects.1,2
Method The Queensland Suicide Register (QSR) is a comprehensive database of suicide mortality data, managed by the Australian Institute for Suicide Research and Prevention (AISRAP) and funded by Queensland Health. The QSR database gathers information on all suicides by Queensland residents since 1990. Data included in the QSR are collated from police reports (since 1994, including psychological autopsy questionnaires), post-mortem reports and toxicology analyses, all of which are provided by the Queensland Office of the State Coroner. Cases are classified in one of three categories, following the Suicide Classification Flow Chart (Figure 1) developed by AISRAP: 1. Beyond reasonable doubt: The available information refers to one or more significant factors that, in combination, constitute a pattern highly indicative of suicide; 2. Probable: The available information is not sufficient to allow for a judgment of ‘beyond reasonable doubt’, but is still more consistent with a death by suicide than by any other means; and 3. Possible: The available information is suggestive of suicide, but there is the substantial possibility that the death may be due to other internal or external causes of death (these cases were excluded from our analyses). The current project included suicide deaths recorded in Queensland between 1990 and 2009 that had an
On the assumption of a Poisson process, we calculated the average number of suicides for the period of interest and computed the probability of a count as high as the highest count for days of the holiday or special period. We performed our calculations using the online calculator at http://stattrek.com/online-calculator/poisson.aspx. The conventional alpha level of .05 was adjusted, because five tests were being made (one for each period of interest). Using the Bonferroni correction, the alpha level set was .01 (i.e. .05/5).
Results Figure 2 presents the number of suicides that were recorded over the 10-year study period, for each day of the Easter period. The low point was Good Friday and the peak was the Tuesday after Easter Monday. When compared with the average count for the comparison days about that time (28.6), the higher count on the day after Easter Monday was found to be not statistically significant (p = .058). Figure 3 presents the number of suicides recorded for each day of the Christmas period. The high point was Christmas Eve: this was found to be statistically significant (p = .004), when compared to the average number of suicides for the comparison period (30.1). Figure 4 presents the number of suicides for each day of the New Year period. The high point on New Year’s Day
2 Downloaded from apy.sagepub.com at University of Newcastle on September 5, 2014
Barker et al.
Figure 1. Flowchart of suicide classification process in Queensland Suicide Register. was statistically significant (p = .0001), when compared with the average for the comparison period (27.5). Figure 5 presents the number of suicides for the Valentine’s Day period and for the Anzac Day period. In neither case was there much change over the days, nor were any of the counts above the average for their comparison periods (for Valentine’s Day, the comparison average was 28.6 and for Anzac Day, the comparison average was 28.5). In summary, statistically significant increases were found in these data only for Christmas Eve and New Year’s Day.
Discussion Based on previous findings, we may have expected an increase in suicides in the days following most major public holidays,5,7,10 with a decrease on and before the holiday itself.11 Expected exceptions would have been New Year’s Day8 and Valentine’s Day,13 which may show an increase in suicidal behaviours on that day. The results from the QSR suicides examined here agreed with previous work in finding an increase in suicides on New Year’s Day. Such an increase is consistent with the idea of suicide being prompted by a ‘broken promise’.14 The first day of a new year is widely thought of in the community
3 Downloaded from apy.sagepub.com at University of Newcastle on September 5, 2014
Australasian Psychiatry 60
35 30
50
25
40
20
30
15
20
10
10
5 0
0 Day before Good Friday
Good Friday
Easter Saturday
Easter Sunday
Easter Monday
Day a er Easter Monday
Figure 2. Distribution of the number of suicides on each day during the Easter period. 50 45 40 35 30 25 20 15 10 5 0
New Years Eve
New Year’s Day
2-Jan
Figure 4. Distribution of suicides on each day during the New Year’s period. Eve: The evening/night before the given day; Jan: January
30 25 20 Valenne’s Day Anzac Day
15 10 5
Christmas Eve
Christmas Day
Boxing Day
27-Dec
0 Day before
Valenne’s/Anzac Day
Day aer
Figure 3. Distribution of suicides on each day during the Christmas period. Dec: December
Figure 5. Distribution of suicides on each day during the Valentine’s and Anzac day periods.
as a time of promise and fresh beginnings. For some, this may heighten a sense of hopelessness, because previous years left the promise unfulfilled and the prospect of another such year may trigger suicide.
suicide deaths did not depart significantly from the average of the comparison periods about that time.
Such an interpretation is not applicable ipso facto to explain the increase in suicides on Christmas Eve. However, the Christmas period is traditionally a time for celebration with family and friends, but for those without such an opportunity, the beginning of such a time may intensify feelings of isolation or the pain of broken relationships. This may help to interpret the increase we observed here. An important consideration for both Christmas Eve and New Year’s Day is the increase in alcohol intake that is traditionally associated with these festive occasions. Alcohol consumption is a risk factor for suicide in its own right and may exacerbate any effect that personal factors such as loss and disappointment might have; therefore, the role of alcohol in suicidal behaviour at this time of the year should not be underestimated. The Easter period was not found to show a statistically significant increase in suicides. There was a high point on the Tuesday after Easter Monday, which for many people signals a return to work, but the difference in
Unlike previous findings on non-fatal suicidal behaviour, the current study failed to find an increase in suicides on Valentine’s Day. In Australia, Valentine’s Day is not a public holiday and although there is commercial promotion of the day, interest is likely confined to young people or those with strong romantic attachments. Previous research finding an increase in suicidal behaviour undertaken in the UK focuses on suicide attempts.13 It is possible that suicidal behaviour around this time may depend on the importance of this day in different countries. Alternatively, suicide attempts around this time may relate to a romantic relationship, which the day celebrates. It would be easy to speculate that non-fatal suicidal behaviour could be aimed at manipulating a troubled relationship; however, this investigation only targeted fatal suicidal behaviour (which is significantly different in many aspects from non-fatal suicidal behaviour), and no increase in deaths due to suicide was evidenced. By contrast, Anzac Day has general public significance in Australia. It commemorates the valour of soldiers from Australia and New Zealand in the Gallipoli campaign in
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Barker et al.
the First World War; and by extension, the contribution of all Australians who have lost their lives in defence of their country, over the years. The day is a holiday marked by street parades in cities, suburbs and towns around the country. In recent times, business is not closed on that day (as it was for many years); but it is a sombre day and, for many war veterans, the day is accompanied by an increase in alcohol use. For those who lost a loved one in military service, it could well revive thoughts and feelings of bereavement. We are not aware of any previous examination of suicide on Anzac Day with which we can compare our current findings, but the result here is of it having essentially no effect.
Funding
The results reported here were based on a study of suicide cases for only one state of Australia, and the sample investigated does not have the same magnitude of some databases used internationally. The power to detect statistically significant effects was, therefore, lower than what might be considered optimal and we cannot claim the sample was representative of the population of the entire country. That said, the only difference that may have proved statistically significant with more precise estimates was the apparent increase in suicide on the day after the end of the Easter period. As for representativeness, Queensland suicide rates continue to be higher than those of New South Wales, Australian Capital Territory and Victoria; however, they also continue to be lower than those of the Northern Territory and Tasmania, and similar to South Australia and Western Australia.19 With regard to alcohol use, Queensland has a higher rate of hospitalisation for alcohol-related injuries than a number of other Australian states.20 To the extent that alcohol is involved in the increased incidence of suicide on the special days reported here, our findings in Queensland may not generalise to other states and territories.
2. Sun JJ, Guo XX, Ma JJ, et al. Seasonality of suicide in Shandong China, 1991–2009: Associations with gender, age, area and methods of suicide. J Affective Disord 2011; 135: 258–266.
One other possible limitation of our study is that the comparison periods for Christmas and New Year included periods when many Australians typically take a summer vacation. If these periods before and after Christmas and New Year’s Day are associated with a decrease in suicide, this may have produced an inflation of the incidence of suicide on the days observed. Such an effect would of course be expected to influence all days in the Christmas/ New Year period, and not just the days found here. We considered it important to control for the seasonality effect that was previously reported1 and, for this reason, we employed comparison periods that were close in time to the special days of interest.
12. Bergen H and Hawton K. Variation in deliberate self-harm around Christmas and New Year. Social Sci Med 2007; 65: 855–867.
The practical implications of the present findings are that greater vigilance with respect to suicidal behaviour in Australia is warranted around New Year’s Day and the beginning of the Christmas period. Gatekeepers should be alert to signs that might manifest at these times and implement, where necessary, appropriate prevention strategies.
This work was supported by funding from the Australian Department of Health (given to the Australian Institute for Suicide Research and Prevention (AISRAP), a National Centre of Excellence in Suicide Prevention and a Collaborating Centre for Research and Training in Suicide Prevention of the World Health Organization (WHO)).
Disclosure The authors report no conflict of interest. The authors alone are responsible for the content and writing of the paper.
References 1. Cantor CH, Hickey PA and De Leo D. Seasonal variation in suicide in a predominantly Caucasian tropical/subtropical region of Australia. Psychopathology 2000; 33: 303–306.
3. Ohtsu T, Kokaze A, Osaki Y, et al. Blue Monday phenomenon among men: Suicide deaths in Japan. Acta Medica Okayama 2009; 63: 231–236. 4. Law CK and De Leo D. Seasonal differences in the day-of-the-week pattern of suicide in Queensland, Australia. Int J Environ Res Pub Health 2013; 10:2825–33. doi: 10.3390/ ijerph10072825. 5. Jessen G, Jensen BF, Arensman E, et al. Attempted suicide and major public holidays in Europe: Findings from the WHO/EURO Multicentre Study on Parasuicide. Acta Psychiatrica Scandinav 1999; 99: 412–418. 6. Jessen G and Jensen BF. Postponed suicide death? Suicides around birthdays and major public holidays. Suicide Life Threat Behav 1999; 29: 272–283. 7. Nishi M, Miyake H, Okamoto H, et al. Relationship between suicide and holidays. J Epidemiol 2000; 10: 317–320. 8. Ajdacic-Gross V, Lauber C, Bopp M, et al. Reduction in the suicide rate during Advent - A time series analysis. Psychiatry Res 2008; 157: 139–146. 9. Zonda T, Bozsonyi K, Veres E, et al. The impact of holidays on suicide in Hungary. Omega 2008; 58: 153–162. 10. Kalediene R and Petrauskiene J. Inequalities in daily variations of deaths from suicide in Lithuania: Identification of possible risk factors. Suicide Life Threat Behav 2004; 34: 138–146. 11. Bridges FS. Rates of homicide and suicide on major national holidays. Psycholog Rep 2004; 94: 723–724.
13. Davenport SM and Birtle J. Association between parasuicide and Saint Valentine’s Day. Brit Med J 1990; 300: 783–784. 14. Gabennesch H. When promises fail: A theory of temporal fluctation in suicide. Social Forces 1988; 67: 129–145. 15. Ajdacic-Gross V, Knöpfli D, Landolt K, et al. Death has a preference for birthdays - An analysis of death time series. Ann Epidemiol 2012; 22: 603–606. 16. Ajdacic-Gross V, Bopp M, Sansossio R, et al. Diversity and change in suicide seasonality over 125 years. J Epidemiol Commun Health 2005; 59: 967–972. 17. Brådvik LL and Berglund MM. A suicide peak after weekends and holidays in patients with alcohol dependence. Suicide Life Threat Behav 2003; 33: 186–191. 18. Neuner T, Hübner-Liebermann B, Wolfersdorf M, et al. Time patterns of inpatient suicides. Int J Psychiatr Clin Pract 2010; 14: 95–101. 19. De Leo D, Sveticic J and Kumpula EK. Suicide in Queensland 2008–2010: Mortality rates and related data. Brisbane: Australian Institute for Suicide Research and Prevention, 2013. 20. Chikritzh T, Catalano P, Stockwell T, et al. Australian alcohol indicators: Patterns of alcohol use and related harms for Australian states and territories. Perth: National Drug Research Institute, 2003.
5 Downloaded from apy.sagepub.com at University of Newcastle on September 5, 2014
Suicide around public holidays Emma Barker, John O'Gorman and Diego De Leo Australas Psychiatry published online 4 February 2014 DOI: 10.1177/1039856213519293 The online version of this article can be found at: http://apy.sagepub.com/content/early/2014/02/04/1039856213519293 A more recent version of this article was published on - Apr 8, 2014
Published by: http://www.sagepublications.com
On behalf of:
The Royal Australian and New Zealand College of Psychiatrists
Additional services and information for Australasian Psychiatry can be found at: Email Alerts: http://apy.sagepub.com/cgi/alerts Subscriptions: http://apy.sagepub.com/subscriptions Reprints: http://www.sagepub.com/journalsReprints.nav Permissions: http://www.sagepub.com/journalsPermissions.nav
Version of Record - Apr 8, 2014 >> OnlineFirst Version of Record - Feb 4, 2014 What is This?
Downloaded from apy.sagepub.com at University of Newcastle on September 5, 2014
519293
research-article2014
APY0010.1177/1039856213519293Australasian PsychiatryBarker et al.
AP
Suicide around public holidays Emma Barker Australian Institute for Suicide Research and Prevention, Griffith University,
Australasian Psychiatry 1–5 © The Royal Australian and New Zealand College of Psychiatrists 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav DOI: 10.1177/1039856213519293 apy.sagepub.com
Brisbane, QLD, Australia
John O’Gorman Australian Institute for Suicide Research and Prevention, Griffith University, Brisbane, QLD, Australia Diego De Leo Australian Institute for Suicide Research and Prevention, Griffith University, Brisbane, QLD, Australia
Abstract Objective: To examine the frequency of suicides on holidays and special days of the year, specifically in Queensland, Australia. Methods: We analysed data from the Queensland Suicide Register between 1990 and 2009. The days examined were: Easter, Christmas, New Year, Valentine’s Day and Anzac Day. We compared suicide cases on these days with the average counts for periods before and after the days. Results: There was a statistically significant increase in suicides on Christmas Eve and on New Year’s Day. Our results are discussed in light of trends reported in the literature. Conclusion: The beginning and end of the festive season are times when special attention is warranted for those with a heightened risk of suicide. Keywords: Australia, festive season, holiday, Queensland, risk, suicide
R
esearch suggests that rates of suicide do not remain consistent throughout the year; rather there appear to be temporal patterns of suicide, influenced by the season1,2 and day of the week.3,4 Another time when suicidal behaviour may fluctuate is the period surrounding significant public holidays.5 Studies indicate that the rates of suicide may increase in the days after Christmas6,7 and during the New Year period.6,8,9 This effect does not appear to be restricted to the Christmas/New Year period, as significant increases in suicides are noted around Easter,10 in particular the Saturday after Good Friday.6 Public holidays do not necessarily mean an increase in suicide, however, as rates decrease on Christmas Day itself6 and other significant days during the Easter period, including Easter Sunday and Monday.6,9 Bridges11 supports the finding of a decrease in suicide on the actual day of the holiday in the US, finding for all holidays (except for New Year’s Day) that the average suicide rate declined from 33.7 to 31.5 per 100 million persons, per day.11 Studies including Emergency Department presentations for non-fatal suicidal behaviour have found similar results to those focusing on fatal suicidal behaviour. Jessen et al.5 find fewer suicide attempts than expected before Christmas, but more attempts after Christmas (a 39% increase) and on New Year’s Day.5 However, these
results were not as consistent as with fatal suicidal behaviour: research finds a decrease in admissions on Christmas day, but no significant increase in the following 11 days.12 Valentine’s Day appears to be the only special day, other than New Year’s Day, that sees an increase in suicidal behaviour on the holiday itself.13 There are two main hypotheses in the literature that may offer some explanation for the fluctuations in suicide around public holidays. The theory of the ‘broken promise effect’ presents the idea that certain days of the year promise more than they can deliver, leaving individuals feeling deflated afterwards and increasing the risk for suicide.14 The trends reported in the current literature for special days and public holidays appear to be consistent with research on birthdays15 and seasons,16 which support the idea of a broken promise effect during these times. Holiday periods, anticipated to be an enjoyable time, may coincide with extra life stressors, including family conflict, alcohol use and increased spending6 that may exacerbate loneliness in those who are not able to share the holiday time with their families. Corresponding author: Diego De Leo, Australian Institute for Suicide Research and Prevention (AISRAP), Griffith University, 176 Messines Ridge Road, Brisbane, QLD 4122, Australia. Email: [email protected]
1 Downloaded from apy.sagepub.com at University of Newcastle on September 5, 2014
Australasian Psychiatry
A second possible reason for the decrease in suicide witnessed on the holiday itself, and the increase after the holiday, involves the prospect of returning to work after the holiday. This is consistent with previous findings that suicide rates are highest at the beginning of the work week, particularly Mondays, and decline as the week progresses3,4; and indications that New Year’s Day, which generally signifies the end of the holiday season and beginning of a new working year, is associated with an increase in suicides. This is also supported by the fact that research in this area involving psychiatric inpatients fails to find such strong effects.17,18 The exception is Valentine’s Day, which does not involve a day off work, with suicides around this time being more likely to be influenced by the romantic aspects of the day.13
accurate date of death available for analysis. The total number of cases meeting these criteria was 10,511. We excluded 46 cases because the date of death could not be ascertained. The number of days between the date of death for each individual and each of the seven significant days under investigation was calculated; and we recorded the number of suicide deaths occurring the day before, on and after that public holiday or special day. Six suicide cases occurred during the New Year’s period in 1990. These cases were excluded from the final analysis, because there was no December 1989 data available for comparison. Similarly, we excluded another five cases because they occurred on or around Christmas 2009, and no January 2010 data were available for comparison at the time we wrote this article.
The aim of the current study was to evaluate the fluctuation of suicide around major public holidays and significant days in Australia. The days selected were the days of Easter, Christmas Day, New Year and Valentine’s Day (which was studied previously) and Anzac Day (25 April). The latter is a public holiday and a day of special significance to the Australian community, which recognises the contribution of those who lost their lives in the defence of their country.
To provide a basis for comparison, we made counts of suicide for the days corresponding to the holidays and special days, and 1 week before and 1 week after Anzac Day and Valentine’s Day. For Easter, we made counts of suicides for the 6 days in March before the Easter period and for the 6 days in April/May after the Easter period. In the case of Christmas and the New Year (which are separated by 1 week), the comparison period for after Christmas was displaced to the week after the New Year; and the comparison period before New Year was displaced to the week before Christmas. This provided an observation window before and after the period of interest, to establish the average number of suicides about that time. We based the estimate on a period ‘about that time’, because suicide is known to show seasonal effects.1,2
Method The Queensland Suicide Register (QSR) is a comprehensive database of suicide mortality data, managed by the Australian Institute for Suicide Research and Prevention (AISRAP) and funded by Queensland Health. The QSR database gathers information on all suicides by Queensland residents since 1990. Data included in the QSR are collated from police reports (since 1994, including psychological autopsy questionnaires), post-mortem reports and toxicology analyses, all of which are provided by the Queensland Office of the State Coroner. Cases are classified in one of three categories, following the Suicide Classification Flow Chart (Figure 1) developed by AISRAP: 1. Beyond reasonable doubt: The available information refers to one or more significant factors that, in combination, constitute a pattern highly indicative of suicide; 2. Probable: The available information is not sufficient to allow for a judgment of ‘beyond reasonable doubt’, but is still more consistent with a death by suicide than by any other means; and 3. Possible: The available information is suggestive of suicide, but there is the substantial possibility that the death may be due to other internal or external causes of death (these cases were excluded from our analyses). The current project included suicide deaths recorded in Queensland between 1990 and 2009 that had an
On the assumption of a Poisson process, we calculated the average number of suicides for the period of interest and computed the probability of a count as high as the highest count for days of the holiday or special period. We performed our calculations using the online calculator at http://stattrek.com/online-calculator/poisson.aspx. The conventional alpha level of .05 was adjusted, because five tests were being made (one for each period of interest). Using the Bonferroni correction, the alpha level set was .01 (i.e. .05/5).
Results Figure 2 presents the number of suicides that were recorded over the 10-year study period, for each day of the Easter period. The low point was Good Friday and the peak was the Tuesday after Easter Monday. When compared with the average count for the comparison days about that time (28.6), the higher count on the day after Easter Monday was found to be not statistically significant (p = .058). Figure 3 presents the number of suicides recorded for each day of the Christmas period. The high point was Christmas Eve: this was found to be statistically significant (p = .004), when compared to the average number of suicides for the comparison period (30.1). Figure 4 presents the number of suicides for each day of the New Year period. The high point on New Year’s Day
2 Downloaded from apy.sagepub.com at University of Newcastle on September 5, 2014
Barker et al.
Figure 1. Flowchart of suicide classification process in Queensland Suicide Register. was statistically significant (p = .0001), when compared with the average for the comparison period (27.5). Figure 5 presents the number of suicides for the Valentine’s Day period and for the Anzac Day period. In neither case was there much change over the days, nor were any of the counts above the average for their comparison periods (for Valentine’s Day, the comparison average was 28.6 and for Anzac Day, the comparison average was 28.5). In summary, statistically significant increases were found in these data only for Christmas Eve and New Year’s Day.
Discussion Based on previous findings, we may have expected an increase in suicides in the days following most major public holidays,5,7,10 with a decrease on and before the holiday itself.11 Expected exceptions would have been New Year’s Day8 and Valentine’s Day,13 which may show an increase in suicidal behaviours on that day. The results from the QSR suicides examined here agreed with previous work in finding an increase in suicides on New Year’s Day. Such an increase is consistent with the idea of suicide being prompted by a ‘broken promise’.14 The first day of a new year is widely thought of in the community
3 Downloaded from apy.sagepub.com at University of Newcastle on September 5, 2014
Australasian Psychiatry 60
35 30
50
25
40
20
30
15
20
10
10
5 0
0 Day before Good Friday
Good Friday
Easter Saturday
Easter Sunday
Easter Monday
Day a er Easter Monday
Figure 2. Distribution of the number of suicides on each day during the Easter period. 50 45 40 35 30 25 20 15 10 5 0
New Years Eve
New Year’s Day
2-Jan
Figure 4. Distribution of suicides on each day during the New Year’s period. Eve: The evening/night before the given day; Jan: January
30 25 20 Valenne’s Day Anzac Day
15 10 5
Christmas Eve
Christmas Day
Boxing Day
27-Dec
0 Day before
Valenne’s/Anzac Day
Day aer
Figure 3. Distribution of suicides on each day during the Christmas period. Dec: December
Figure 5. Distribution of suicides on each day during the Valentine’s and Anzac day periods.
as a time of promise and fresh beginnings. For some, this may heighten a sense of hopelessness, because previous years left the promise unfulfilled and the prospect of another such year may trigger suicide.
suicide deaths did not depart significantly from the average of the comparison periods about that time.
Such an interpretation is not applicable ipso facto to explain the increase in suicides on Christmas Eve. However, the Christmas period is traditionally a time for celebration with family and friends, but for those without such an opportunity, the beginning of such a time may intensify feelings of isolation or the pain of broken relationships. This may help to interpret the increase we observed here. An important consideration for both Christmas Eve and New Year’s Day is the increase in alcohol intake that is traditionally associated with these festive occasions. Alcohol consumption is a risk factor for suicide in its own right and may exacerbate any effect that personal factors such as loss and disappointment might have; therefore, the role of alcohol in suicidal behaviour at this time of the year should not be underestimated. The Easter period was not found to show a statistically significant increase in suicides. There was a high point on the Tuesday after Easter Monday, which for many people signals a return to work, but the difference in
Unlike previous findings on non-fatal suicidal behaviour, the current study failed to find an increase in suicides on Valentine’s Day. In Australia, Valentine’s Day is not a public holiday and although there is commercial promotion of the day, interest is likely confined to young people or those with strong romantic attachments. Previous research finding an increase in suicidal behaviour undertaken in the UK focuses on suicide attempts.13 It is possible that suicidal behaviour around this time may depend on the importance of this day in different countries. Alternatively, suicide attempts around this time may relate to a romantic relationship, which the day celebrates. It would be easy to speculate that non-fatal suicidal behaviour could be aimed at manipulating a troubled relationship; however, this investigation only targeted fatal suicidal behaviour (which is significantly different in many aspects from non-fatal suicidal behaviour), and no increase in deaths due to suicide was evidenced. By contrast, Anzac Day has general public significance in Australia. It commemorates the valour of soldiers from Australia and New Zealand in the Gallipoli campaign in
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Barker et al.
the First World War; and by extension, the contribution of all Australians who have lost their lives in defence of their country, over the years. The day is a holiday marked by street parades in cities, suburbs and towns around the country. In recent times, business is not closed on that day (as it was for many years); but it is a sombre day and, for many war veterans, the day is accompanied by an increase in alcohol use. For those who lost a loved one in military service, it could well revive thoughts and feelings of bereavement. We are not aware of any previous examination of suicide on Anzac Day with which we can compare our current findings, but the result here is of it having essentially no effect.
Funding
The results reported here were based on a study of suicide cases for only one state of Australia, and the sample investigated does not have the same magnitude of some databases used internationally. The power to detect statistically significant effects was, therefore, lower than what might be considered optimal and we cannot claim the sample was representative of the population of the entire country. That said, the only difference that may have proved statistically significant with more precise estimates was the apparent increase in suicide on the day after the end of the Easter period. As for representativeness, Queensland suicide rates continue to be higher than those of New South Wales, Australian Capital Territory and Victoria; however, they also continue to be lower than those of the Northern Territory and Tasmania, and similar to South Australia and Western Australia.19 With regard to alcohol use, Queensland has a higher rate of hospitalisation for alcohol-related injuries than a number of other Australian states.20 To the extent that alcohol is involved in the increased incidence of suicide on the special days reported here, our findings in Queensland may not generalise to other states and territories.
2. Sun JJ, Guo XX, Ma JJ, et al. Seasonality of suicide in Shandong China, 1991–2009: Associations with gender, age, area and methods of suicide. J Affective Disord 2011; 135: 258–266.
One other possible limitation of our study is that the comparison periods for Christmas and New Year included periods when many Australians typically take a summer vacation. If these periods before and after Christmas and New Year’s Day are associated with a decrease in suicide, this may have produced an inflation of the incidence of suicide on the days observed. Such an effect would of course be expected to influence all days in the Christmas/ New Year period, and not just the days found here. We considered it important to control for the seasonality effect that was previously reported1 and, for this reason, we employed comparison periods that were close in time to the special days of interest.
12. Bergen H and Hawton K. Variation in deliberate self-harm around Christmas and New Year. Social Sci Med 2007; 65: 855–867.
The practical implications of the present findings are that greater vigilance with respect to suicidal behaviour in Australia is warranted around New Year’s Day and the beginning of the Christmas period. Gatekeepers should be alert to signs that might manifest at these times and implement, where necessary, appropriate prevention strategies.
This work was supported by funding from the Australian Department of Health (given to the Australian Institute for Suicide Research and Prevention (AISRAP), a National Centre of Excellence in Suicide Prevention and a Collaborating Centre for Research and Training in Suicide Prevention of the World Health Organization (WHO)).
Disclosure The authors report no conflict of interest. The authors alone are responsible for the content and writing of the paper.
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