--- United States, 1990--2004
In 2004, suicide was the third leading cause of death among youths and young adults aged 10--24 years in the United States, accounting for 4,599 deaths (1,2). During 1990--2003, the combined suicide rate for persons aged 10--24 years declined 28.5%, from 9.48 to 6.78 per 100,000 persons (2). However, from 2003 to 2004, the rate increased by 8.0%, from 6.78 to 7.32 (2), the largest single-year increase during 1990--2004. To characterize U.S. trends in suicide among persons aged 10--24 years, CDC analyzed data recorded during 1990--2004, the most recent data available. Results of that analysis indicated that, from 2003 to 2004, suicide rates for three sex-age groups (i.e., females aged 10--14 years and 15--19 years and males aged 15--19 years) departed upward significantly from otherwise declining trends. Results further indicated that suicides both by hanging/suffocation and poisoning among females aged 10--14 years and 15--19 years increased from 2003 to 2004 and were significantly in excess of trends in both groups. The results suggest that increases in suicide and changes in suicidal behavior might have occurred among youths in certain sex-age groups, especially females aged 10--19 years. Closer examination of these trends is warranted at federal and state levels. Where indicated, health authorities and program directors should consider focusing suicide-prevention activities on these groups to help prevent suicide rates from increasing further.
Annual data on suicides in the United States during 1990--2004 (1) were obtained from the National Vital Statistics System via WISQARS™ (2) by sex, three age groups (i.e., 10--14, 15--19, and 20--24 years), and the three most common suicide methods (firearm, hanging/suffocation,* and poisoning†). Although coding of mortality data changed from the International Classification of Diseases, Ninth Revision (ICD-9) to the Tenth Revision (ICD-10) beginning in 1999, near total agreement exists between the two revisions regarding classification of suicides (3). Suicide trends during the 15-year period were examined for each sex-age group overall and by method, using a negative binomial rate regression model. Differences between observed rates and model-estimated rates for each year were evaluated using standardized Pearson residuals, which account for the general level of variability in the year-to-year rates. Standardized Pearson residuals >2 or <-2 were used to identify unusual departures from the modeled rate trends. A comprehensive explanation of these methods has been published previously (4).
Significant upward departures from modeled trends in 2004 were identified in total suicide rates for three of the six sex-age groups: females aged 10--14 years and 15--19 years and males aged 15--19 years (Table). The largest percentage increase in rates from 2003 to 2004 was among females aged 10--14 years (75.9%), followed by females aged 15--19 years (32.3%) and males aged 15--19 years (9.0%). In absolute numbers, from 2003 to 2004, suicides increased from 56 to 94 among females aged 10--14 years, from 265 to 355 among females aged 15--19 years, and from 1,222 to 1,345 among males aged 15--19 years.
In 1990, firearms were the most common suicide method among females in all three age groups examined, accounting for 55.2% of suicides in the group aged 10--14 years, 56.0% in the group aged 15--19 years, and 53.4% in the group aged 20--24 years. However, from 1990 to 2004, among females in each of the three age groups, significant downward trends were observed in the rates both for firearm suicides (p<0.01) and poisoning suicides (p<0.05), and a significant increase was observed in the rate for suicides by hanging/suffocation (p<0.01). In 2004, hanging/suffocation was the most common method among females in all three age groups, accounting for 71.4% of suicides in the group aged 10--14 years, 49% in the group aged 15--19 years, and 34.2% in the group aged 20--24 years. In addition, from 2003 to 2004, hanging/suffocation suicide rates among females aged 10--14 and 15--19 years increased by 119.4% (from 0.31 to 0.68 per 100,000 persons) and 43.5% (from 1.24 to 1.78), respectively (Figures 1 and 2). In absolute numbers, from 2003 to 2004, suicides by hanging/suffocation increased from 32 to 70 among females aged 10--14 years and from 124 to 174 among females aged 15--19 years. Aside from 2004, the only other significant departure from trend among females in these two age groups during 1990--2004 was in suicides by hanging/suffocation among females aged 15--19 years in 1996 (Figure 2).
Reported by: KM Lubell, PhD, SR Kegler, PhD, AE Crosby, MD, D Karch, PhD, Div of Violence Prevention, National Center for Injury Prevention and Control, CDC.
The findings in this report indicate that 2004 suicide rates for males aged 15--19 years and females aged 10--14 years and 15--19 years diverged upward significantly from modeled trends during 1990--2004. For females in the two age groups, significant departures were observed for 2004 in suicides by hanging/suffocation and poisoning. The rate for suicide by hanging/suffocation among females aged 10--14 years more than doubled from 2003 to 2004, from 0.31 to 0.68 per 100,000 population. During 1990--2003, the highest yearly rate for such deaths among females in this age group was 0.35 per 100,000 population in 1998.
The marked increases in suicide rates among females in the two younger age groups suggest possible changes in risk factors for suicide and the methods used, with greater use of methods (e.g., hanging by rope) that are readily accessible (5). Scientific knowledge regarding risk factors for suicide in young females is limited. Research that focuses on suicide mortality has emphasized males, who constitute approximately three fourths of suicide decedents aged 10--19 years (2). In contrast, research on suicidal behavior among females primarily has examined factors related to suicidal thoughts and nonfatal self-inflicted injuries. One comparative study, conducted in Singapore, suggested that perceptions of interpersonal relationship problems are more common among young female suicide decedents than among their male counterparts (6). Family discord, legal/disciplinary problems, school concerns, and mental health conditions such as depression increase the risk for suicide among youths of both sexes (6,7). Drug/alcohol use can exacerbate these problems (7).
Recent reports have detailed unintentional asphyxia fatalities resulting from adolescents playing "the choking game" (i.e., intentionally restricting the supply of oxygen to the brain, often with a ligature, to induce a brief euphoria). Some of these fatalities likely are misclassified as suicides. However, such deaths are unlikely to account for a substantial portion of the recent increases in hanging/suffocation suicides among young girls. The available evidence suggests that choking-game fatalities occur predominantly among boys (8). In addition, analysis of hanging/suffocation deaths classified as unintentional or undetermined in this population did not reveal increases that paralleled those in hanging/suffocation suicides (CDC, unpublished data, 2007).
The findings in this report are subject to at least three limitations. First, because U.S. mortality data currently are available only through 2004, whether the increases observed in 2004 represent changes in trends or single-year anomalies is not clear and suggests a need for further study as more current data become available. Second, official mortality data for suicides might include classification errors. Previous research has highlighted the extent to which suicides are undercounted (9). Finally, because U.S. mortality data include limited variables, these data do not allow examination of potential differences or changes in the underlying risk factors for fatal suicidal behavior among young females. Other data sources (e.g., the National Violent Death Reporting System) that collect a broader array of information about the circumstances surrounding suicides (10) might provide additional insights.
These findings demonstrate the potential mutability of youth suicidal behavior. Public health researchers and suicide-prevention practitioners need to learn more about both the risk factors for suicide among young females and effective strategies for suicide prevention. The trends in suicide rates and methods described in this report, if confirmed, suggest that prevention measures focused solely on restricting access to the most lethal means are likely to have limited success. Prevention measures should address the underlying reasons for suicide in populations that are vulnerable.
National Center for Health Statistics. Multiple cause-of-death public-use data files, 1990 through 2004. Hyattsville, MD: US Department of Health and Human Services, CDC, National Center for Health Statistics; 2007.
CDC. Web-based Injury Statistics Query and Reporting System (WISQARS™). Atlanta, GA: US Department of Health and Human Services, CDC; 2007. Available at http://www.cdc.gov/ncipc/wisqars/default.htm.
Anderson RN, Minino AM, Fingerhut LA, Warner M, Heinen MA. Deaths: injuries, 2001. Natl Vital Stat Rep 2004;52:1--5.
Agresti A. An introduction to categorical data analysis. 2nd ed. Hoboken, NJ: Wiley; 2007.
CDC. Methods of suicide among persons aged 10--19 years---United States, 1992--2001. MMWR 2004;53:471--4.
Ang RP, Chia BH, Fung DSS. Gender differences in life stressors associated with child and adolescent suicides in Singapore from 1995 to 2003. Int J Soc Psychiatry 2006;52:561--70.
Kloos AL, Collins R, Weller RA, Weller EB. Suicide in preadolescents: who is at risk? Curr Psychiatry Rep 2007;9:89--93.
Le D, Macnab AJ. Self strangulation by hanging from cloth towel dispensers in Canadian schools. Inj Prev 2001;7:231--3.
O'Carroll PW. A consideration of the validity and reliability of suicide mortality data. Suicide Life Threat Behav 1989;19:1--16.
Steenkamp M, Frazier L, Lipskiy N, et al. The National Violent Death Reporting System: an exciting new tool for public health surveillance. Inj Prev 2006;12(Suppl 2):ii3--5.
* Includes self-inflicted asphyxiation and ligature strangulation.
† Includes intentional drug overdose and carbon monoxide exposure.
National Suicide Prevention Week --- September 9--15, 2007
Suicide is the eleventh leading cause of death in the United States and the third leading cause among youths and young adults aged 10--24 years, accounting for 4,599 deaths in this age group in 2004 (1).
Approximately 142,000 visits are made to emergency departments by persons in this age group each year to receive medical care for self-inflicted injuries (1).
Known risk factors for suicide include
1) a previous suicide attempt,
2) history of depression or other mental illness,
3) alcohol or drug abuse,
4) family history of suicide or violence,
5) physical illness, and
6) feeling alone (2).
However, because U.S. mortality data lack information on many risk factors for suicide, reasons for subgroup vulnerabilities are not addressed. Using data from the National Violent Death Reporting System, CDC has begun to compile additional information about the circumstances of suicide to better understand why suicides occur and how they might be prevented.
During National Suicide Prevention Week, September 9--15, 2007, CDC encourages parents, educators, health-care providers, and health authorities to learn more about suicide, including the groups at greatest risk, warning signs for suicide, and potential prevention strategies.
Additional information is available at http://www.cdc.gov/ncipc/dvp/suicide/default.htm.