Suicides --- United States, 1999--2007

Alex E. Crosby, MD

LaVonne Ortega, MD

Mark R. Stevens, MSPH

National Center for Injury Prevention and Control, CDC

Corresponding author: Alex E. Crosby, MD, Division of Violence Prevention, National Center for Injury Prevention and Control, 4770 Buford Highway, NE, MS F-63, Atlanta, GA 30341. Telephone: 770-488-4410; Fax: 770-488-4222; E-mail: aec1@cdc.gov.

Injury from self-directed violence, which includes suicidal behavior and its consequences, is a leading cause of death and disability. In 2007, suicide was the 11th leading cause of death in the United States and the cause of 34,598 deaths (1). In 2000, the estimated cost of self-directed violence (fatal and nonfatal) was $33 billion ($32 billion in productivity losses and $1 billion in medical costs) (2). Suicide rates are influenced by biological, psychological, social, moral, political, and economic factors (3). Self-directed violence in the United States affects all racial/ethnic groups but often is misperceived to be a problem solely affecting non-Hispanic white males (4).

To determine differences in the prevalence of suicide by sex, race/ethnicity, age, and geographic region in the United States, CDC analyzed 1999--2007 data from the Web-based Injury Statistics Query and Reporting System --- Fatal (WISQARS Fatal) (5) and the National Vital Statistics System (NVSS). Mortality data originate from NVSS, which collects death certificate data filed in the 50 states and the District of Columbia (1). Data in this report were based on suicides from any cause and include the 1999--2007 data years. The WISQARS database contains mortality data based on NVSS and population counts for all U.S. counties based on U.S. Census data. Counts and rates of death can be obtained by underlying cause of death, mechanism of injury, state, county, age, race, sex, year, injury cause of death (e.g., firearm, poisoning, or suffocation) and by manner of death (e.g., suicide, homicide, or unintentional injury) (4).

Unadjusted (crude) death rates were based on resident population data from the U.S. Census Bureau (5). Confidence intervals were calculated in two ways: 1) groupings of <100 deaths were calculated by using the gamma method (1), and 2) groupings of ≥100 deaths were calculated by using a normal approximation (1).

NVSS codes racial categories as white, black, American Indian/Alaskan Native (AI/AN), and Asian/Pacific Islander (A/PI); ethnicity is coded separately as Hispanic or non-Hispanic (1). All references to a specific race refer to non-Hispanic members (e.g., non-Hispanic white and non-Hispanic black). Differences in rates between two populations were compared using the z statistic based on a normal approximation at a critical value of α = 0.05 (1). Because coding of the mortality data changed to the International Classification of Diseases, Tenth Revision (ICD-10) beginning in 1999, analyses by year and race/ethnicity were conducted for 1999--2007 to examine rate changes during that period. To compare differences in rates across the years 1999--2007, trend analyses to test statistical significance were conducted using a negative binomial rate regression model (6).

In 2007, a total of 34,598 suicides occurred in the United States; 83.5% of suicides were among whites, 7.1% among Hispanics, 5.5% among blacks, 2.5% among A/PIs, and 1.1% among AI/ANs (Table). Although AI/ANs represented the smallest proportion of suicides of all racial/ethnic groups, they shared the highest rates with whites. Overall, the suicide rate for males (18.4 per 100,000 population) was approximately 4 times (383%) greater than for females (4.8 per 100,000 population). In each of the racial/ethnic groups, suicide rates were higher for males than for females, but the male-female ratio for suicide differs among these groups. Among whites, the male-female ratio was 3.8; among Hispanics, 5.0; among blacks, 5.0; among A/PIs, 2.4; and among AI/ANs, 3.7. During 2007, 4,754 (13.7%) suicides occurred in the Northeast, 7,515 (21.7%) in the Midwest, 8,940 (25.8%) in the West, and 13,389 (38.7%) in the South (Table). Regional crude suicide rates were significantly higher for persons living in the West (12.8 per 100,000 population), followed by the South (12.1), Midwest (11.3), and Northeast (8.7). An assessment of trends for the years 1999--2007 showed increases for AI/ANs (p<0.001) and whites (p<0.001) and decreases for blacks (p<0.001); no significant changes occurred in trends for rates among Hispanics and A/PIs.

Suicide rates by race/ethnicity and age group demonstrated different patterns by racial/ethnic group, with the highest rates occurring among AI/AN adolescents and young adults (Figure). Rates among AI/ANs, blacks, and Hispanics tended to be highest among adolescents and young adults, then declined or leveled off with increasing age. In contrast, rates among whites were highest among those aged 40--54 years. Among A/PIs, rates were highest for persons aged ≥65 years. Although the overall rates for AI/ANs were similar to those of whites, the rates among adolescent and young adult AI/ANs aged 15--29 years were substantially higher. AI/AN youths had substantially greater rates of suicide than young persons of other racial/ethnic groups. In addition, suicide ranked as the fourth leading cause of years of potential life lost (YPLL) among AI/ANs, accounting for 7.5% of all YPLL among AI/ANs (5). Multiple factors contribute to the high rates of suicide among AI/AN populations, including individual-level factors (e.g., alcohol and substance misuse and mental illness), family- or peer-level factors (e.g., family disruption or suicidal behavior of others), and societal-level factors (e.g., poverty, unemployment, discrimination, and historical trauma [i.e., cumulative emotional and psychological wounding across generations]) (7). Although certain protective factors exist within AI/AN communities, including spirituality and cultural continuity, the factors are often outweighed by the magnitude of the risk factors (7). The regional differences found in this report are consistent with previous studies conducted in the United States (8). These studies have shown that regional differences in demographic patterns (i.e., age, race/ethnicity, and sex) and in suicide methods do not account completely for variations in suicide.

Suicide prevention efforts throughout the United States tend to focus on counseling, education, and clinical intervention strategies for persons at risk for suicide (3). Although these approaches provide limited individual protection, they also require high levels of effort and commitment and might have a limited population-level impact, a critical goal of public health (9). In contrast, strategies that seek to address societal-level factors demonstrated to be associated with suicide (e.g., economic strain, poverty, and misuse of alcohol and other psychoactive substances) and improving the health system infrastructure in impoverished and underserved communities to address this problem might have a greater effect but need additional development and testing (9).

The findings presented in this report are subject to at least two limitations. First, the number of suicides is undercounted in the database (and such undercounts have not changed in recent years) (10); therefore, the suicide rates in this report are likely to be underestimates. Second, injury mortality data likely underestimate by 25%--35% the actual numbers of deaths for AI/ANs and certain other racial/ethnic populations (e.g., Hispanics) because of the misclassification of race/ethnicity of decedents on death certificates (11). Because the variables included in U.S. mortality data are limited, the results cannot be used to determine potential factors related to such disparities as mental or physical disability, sexual orientation, or income. Other data sources (e.g., the National Violent Death Reporting System) that collect a broader array of information about the circumstances surrounding suicides and other violent deaths can provide additional insight for suicide prevention programs (12).

Effective, comprehensive suicide prevention programs focus on risk and protective factors, including coping skills, access to mental health treatment, substance misuse, and social support; however, only a limited number have been developed specifically for selected populations (3). An example of a comprehensive prevention program that has been reported to reduce suicidal behavior within an AI/AN community is the Natural Helpers Program (13). This multicomponent program involves personnel who are trained to respond to adolescents and young adults in crisis, notify mental health professionals in the event of a crisis, and provide health education in the schools and community. Other program components include outreach to families after a suicide or other traumatic death, immediate response and follow-up for youths reported to be at risk, alcohol and substance abuse programs, community education about suicide prevention, and suicide-risk screening in mental health and social service programs.

To reduce the rates of suicide among groups that are affected disproportionately, substantial public health investments are needed to address the health and well-being of persons at risk and to support the widespread implementation of culturally relevant and effective programs. Prevention efforts and resources also should be directed toward adults aged 40--54 years, the population that recently has had increases in suicides but often is overlooked as a specific group for prevention efforts (14).

References

1. Xu J, Kochanek KD, Murphy SL, Tejada-Vera B. Deaths: final data for 2007. Hyattsville, MD: US Department of Health and Human Services, CDC, National Center for Health Statistics; 2010. National Vital Statistics Reports Vol. 58, No. 19. Available at http://www.cdc.gov/nchs/data/nvsr/nvsr58/nvsr58_19.pdf.
2. Corso PS, Mercy JA, Simon TR, Finkelstein EA, Miller TR. Medical costs and productivity losses due to interpersonal and self-directed violence in the United States. Am J Prev Med 2007:32:474--82.
3. Goldsmith SK, Pellmar TC, Kleinman AM, Bunney WE, eds. Reducing suicide: a national imperative. Washington, DC: National Academies Press; 2002.
4. Earls F, Escobar JI, Manson SM. Suicide in minority groups: epidemiologic and cultural perspectives. In: Blumenthal SJ, Kupfer DJ, eds. Suicide over the life cycle: risk factors, assessment, and treatment of suicidal patients. Washington, DC: American Psychiatric Publishing; 1990:571--98.
5. CDC. Web-based Injury Statistics Query and Reporting System (WISQARS): fatal injury data. Atlanta, GA: US Department of Health and Human Services, CDC. Available at http://www.cdc.gov/injury/wisqars/fatal.html.
6. Agresti A. An introduction to categorical dta analysis. 2nd ed. Hoboken, NJ:Wiley;2007.
7. Substance Abuse and Mental Health Services Administration (SAMHSA). To live to see the great day that dawns: preventing suicide by American Indian and Alaska Native youth and young adults. Rockville, MD: US Department of Health Human Services, SAMHSA, Center for Mental Health Services; 2010. Publication no. SMA 10-4480.
8. CDC. Regional variations in suicide rates---United States, 1990--1994. MMWR 1997;46:789--93.
9. Frieden TR. A framework for public health action: the health impact pyramid. Am J Public Health 2010;100:590--5.
10. O'Carroll PW. A consideration of the validity and reliability of suicide mortality data. Suicide Life Threat Behav 1989;19:1--16.
11. Arias E, Schauman WS, Eschbach K, Sorlie PD, Backlund E. The validity of race and Hispanic origin reporting on death certificates in the United States. Vital Health Stat 2 2008;148:1--23.
12. 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.
13. May PA, Serna P, Hurt L, DeBruyn LM. Outcome evaluation of a public health approach to suicide prevention in an American Indian tribal nation. Am J Public Health 2005;95:1238--44.
14. CDC. Increases in age-group--specific injury mortality--United States, 1999--2004. MMWR 2007;56:1281--4.

All MMWR HTML versions of articles are electronic conversions from typeset documents. This conversion might result in character translation or format errors in the HTML version. Users are referred to the electronic PDF version (http://www.cdc.gov/mmwr) and/or the original MMWR paper copy for printable versions of official text, figures, and tables. An original paper copy of this issue can be obtained from the Superintendent of Documents, U.S. Government Printing Office (GPO), Washington, DC 20402-9371; telephone: (202) 512-1800. Contact GPO for current prices.

**Questions or messages regarding errors in formatting should be addressed to mmwrq@cdc.gov.