Is suicide contagious? A study of the relation between exposure to the suicidal behavior of others and nearly lethal suicide attempts.

This study sought to determine the association between nearly lethal suicide attempts and exposure to the suicidal behavior of parents, relatives, friends, or acquaintances and to accounts of suicide in the media. The authors conducted a population-based case-control study in Houston, Texas, from November 1992 through July 1995. They interviewed 153 victims of attempted suicide aged 13--34 years who had been treated at emergency departments in Houston and a random sample of 513 control subjects. After controlling for potentially confounding variables, the authors found that exposure to the suicidal behavior of a parent (adjusted OR = 1.5; 95% CI: 0.6, 3.6; p = 0.42) or a nonparent relative (adjusted OR = 1.2; 95% CI: 0.7, 2.0; p = 0.55) was not significantly associated with nearly lethal suicide attempts. Both exposure to the suicidal behavior of a friend or acquaintance (adjusted OR = 0.6; 95% CI: 0.4, 1.0; p = 0.05) and exposure to accounts of suicidal behavior in the media (adjusted OR = 0.2; 95% CI: 0.1, 0.3; p = 0.00) were associated with a lower risk of nearly lethal suicide attempts. Exposure to accounts of suicidal behavior in the media and, to a lesser extent, exposure to the suicidal behavior of friends or acquaintances may be protective for nearly lethal suicide attempts, but further research is needed to better understand the mechanisms underlying these findings.

Population attributable risk: implications of physical activity dose.

PURPOSE: The purpose of this study is to describe the application of population attributable risk estimates in relation to the dose-related benefits or risks of physical activity. METHODS: Assumptions and limitations of population attributable risk calculations and interpretations are reviewed and evaluated in the context of physical activity dose. Theoretical estimates are developed for several hypothetical situations. RESULTS: National estimates of population attributable risk may be inaccurate because definitions and measurement techniques applied in physical activity research studies and physical activity prevalence surveys do not correspond. In addition, it is not established whether vigorous or moderate physical activity are independent contributors, sequential categories, or interactive variables in the process of disease reduction. This information is necessary to calculate population attributable risk most appropriately. CONCLUSION: Estimates of the disease burden of physical inactivity will be improved by two advances in empirical studies: first, the pairing of prevalence and relative risk estimates for nationally representative population-based samples; and second, refined relative risk estimates for various doses of physical activity.

Assigning time-linked exposure status to controls in unmatched case-control studies: alcohol use and nearly lethal suicide attempts.

In case-control studies, determination of alcohol consumption by cases immediately prior to the injury event is often conceptually straightforward. However, determination of consumption status by controls is difficult because they lack a reference point, especially when cases and controls are not individually matched. We describe a method of assigning alcohol consumption status to controls using a 24-hour drinking history, the distribution in time of case events, and the random assignment of a specific time period to each control subject. This methodology offers a practical approach for determining alcohol consumption status among control subjects immediately prior to a case event, when controls lack a reference point and have not been individually matched to cases. Published in 2001 by John Wiley & Sons, Ltd.

Nutritional rickets in Georgia.

Opinions expressed in commentaries are those of the authors and not necessarily those of the American Academy of Pediatrics or its Committees. Commentaries are not peer-reviewed.

Impact of changes in transportation and commuting behaviors during the 1996 Summer Olympic Games in Atlanta on air quality and childhood asthma.

CONTEXT: Vehicle exhaust is a major source of ozone and other air pollutants. Although high ground-level ozone pollution is associated with transient increases in asthma morbidity, the impact of citywide transportation changes on air quality and childhood asthma has not been studied. The alternative transportation strategy implemented during the 1996 Summer Olympic Games in Atlanta, Ga, provided such an opportunity. OBJECTIVE: To describe traffic changes in Atlanta, Ga, during the 1996 Summer Olympic Games and concomitant changes in air quality and childhood asthma events. DESIGN: Ecological study comparing the 17 days of the Olympic Games (July 19-August 4, 1996) to a baseline period consisting of the 4 weeks before and 4 weeks after the Olympic Games. SETTING AND SUBJECTS: Children aged 1 to 16 years who resided in the 5 central counties of metropolitan Atlanta and whose data were captured in 1 of 4 databases. MAIN OUTCOME MEASURES: Citywide acute care visits and hospitalizations for asthma (asthma events) and nonasthma events, concentrations of major air pollutants, meteorological variables, and traffic counts. RESULTS: During the Olympic Games, the number of asthma acute care events decreased 41.6% (4.23 vs 2.47 daily events) in the Georgia Medicaid claims file, 44.1% (1.36 vs 0.76 daily events) in a health maintenance organization database, 11.1% (4.77 vs 4.24 daily events) in 2 pediatric emergency departments, and 19.1% (2.04 vs 1.65 daily hospitalizations) in the Georgia Hospital Discharge Database. The number of nonasthma acute care events in the 4 databases changed -3.1%, +1.3%, -2.1%, and +1.0%, respectively. In multivariate regression analysis, only the reduction in asthma events recorded in the Medicaid database was significant (relative risk, 0.48; 95% confidence interval, 0.44-0.86). Peak daily ozone concentrations decreased 27.9%, from 81.3 ppb during the baseline period to 58.6 ppb during the Olympic Games (P<.001). Peak weekday morning traffic counts dropped 22.5% (P<.001). Traffic counts were significantly correlated with that day's peak ozone concentration (average r = 0.36 for all 4 roads examined). Meteorological conditions during the Olympic Games did not differ substantially from the baseline period. CONCLUSIONS: Efforts to reduce downtown traffic congestion in Atlanta during the Olympic Games resulted in decreased traffic density, especially during the critical morning period. This was associated with a prolonged reduction in ozone pollution and significantly lower rates of childhood asthma events. These data provide support for efforts to reduce air pollution and improve health via reductions in motor vehicle traffic.

Alcohol consumption and nearly lethal suicide attempts.

We conducted a case-control study of the association between nearly lethal suicide attempts and facets of alcohol consumption; namely, drinking frequency, drinking quantity, binge drinking, alcoholism, drinking within 3 hours of suicide attempt, and age began drinking. Subjects were 13-34 years of age. In bivariable analyses, all measures were associated with nearly lethal suicide attempts. Odds ratios ranged from 2.4 for alcoholism to 7.0 for drinking within 3 hours of attempt. All exposure variables except age began drinking exhibited a J-shaped relationship between alcohol exposure and nearly lethal suicide attempt. After controlling for potential confounders and other measures of alcohol exposure, drinking within 3 hours of attempt remained most strongly (odds ratios > 6) associated. Alcoholism remained significantly associated in most models, but at lower strength.

The influence of geographic mobility on nearly lethal suicide attempts.

Teenagers and young adults are very mobile and mobility has been identified as a potential risk factor for suicidal behavior. We conducted a population-based, case-control study of nearly lethal suicide attempts with 153 cases and 513 controls. Study participants were asked about changing residence over the past 12 months. Results indicate that moving in the past 12 months is positively associated with a nearly lethal suicide attempt (adjusted odds ratio of 2.1, with 95% confidence interval of 1.4-3.3), as are specific characteristics of the move (e.g., frequency, recency, distance, and difficulty staying in touch). These findings confirm and extend prior ecologic research by demonstrating a relationship, at the individual level, between the geographic mobility of adolescents and young adults and nearly lethal suicide attempts.

Characteristics of impulsive suicide attempts and attempters.

Suicide attempts often are impulsive, yet little is known about the characteristics of impulsive suicide. We examined impulsive suicide attempts within a population-based, case-control study of nearly lethal suicide attempts among people 13-34 years of age. Attempts were considered impulsive if the respondent reported spending less than 5 minutes between the decision to attempt suicide and the actual attempt. Among the 153 case-subjects, 24% attempted impulsively. Impulsive attempts were more likely among those who had been in a physical fight and less likely among those who were depressed. Relative to control subjects, male sex, fighting, and hopelessness distinguished impulsive cases but depression did not. Our findings suggest that inadequate control of aggressive impulses might be a greater indicator of risk for impulsive suicide attempts than depression.

Medical conditions and nearly lethal suicide attempts.

Physical illness has been studied as a risk factor for suicidal behavior, but little is known about this relationship among younger persons. We conducted a population-based, case-control study in Houston, Texas, from November 1992 through September 1995. The final sample consisted of 153 case- and 513 control-subjects aged 13 to 34 years. Case patients were identified at hospital emergency departments and met criteria for a nearly lethal suicide attempt. Control subjects were recruited via a random-digit-dial telephone survey. Case patients were more likely than controls to report having any serious medical conditions (crude OR = 3.23; 95% CI = 2.12-4.91). After controlling for age, race/ethnicity, alcoholism, depression, and hopelessness, the adjusted odds ratio for men was 4.76 (95% CI = 1.87-12.17), whereas the adjusted odds ratio for women was 1.60 (95% CI-0.62-4.17), suggesting that young men with medical conditions are at increased risk for nearly lethal suicide attempts. Increased efforts to identify and appropriately refer these patients are needed.

An unmatched case-control study of nearly lethal suicide attempts in Houston, Texas: research methods and measurements.

This article details the research methods and measurements used in conducting a population-based, case-control study of nearly lethal suicide attempts among persons aged 13-34 years, residing in Houston, Texas. From November 1992 to July 1995, we interviewed 153 case subjects presenting at one of three participating hospital emergency departments and used random digit dialing to identify 513 control subjects residing in the same catchment area in which cases were enlisted. Unlike most research in this area, this study was designed to extend our understanding of suicidal behavior and prevention activities beyond identification and treatment of depression and other mental illnesses. We discuss the overall strengths and weaknesses of our study design and conclude that this methodology is well suited for studying rare outcomes such as nearly lethal suicide.

Deaths due to injury in the military.

INTRODUCTION: More military personnel die of injuries each year than any other cause. This paper provides a basic epidemiologic description of injury deaths in the military. METHODS: Using fatality data from the Department of Defense Directorate of Information and Operations Reports and population data from the Defense Manpower Data Center, death rates of men and women in the military services for unintentional injury, suicide, homicide, and illness were calculated for the 1980-1992 period. RESULTS: From 1980 to 1992, injuries (unintentional injuries, suicides, and homicides combined) accounted for 81% of all nonhostile deaths among active duty personnel in the Armed Services. The overall death rate due to unintentional injuries was 62.3 per 100,000 person-years. The suicide rate was 12.5, the homicide rate 5.0, and the death rate due to illness 18.4. From 1980 to 1992 mortality from unintentional injuries declined about 4% per year. The rates for suicide and homicide were stable. Men in the services die from unintentional injuries at about 2.5 times the rate of women and from suicides at about twice the rate of women. Women in the military, however, have a slightly higher homicide rate than men. CONCLUSION: Injuries (unintentional injuries, suicides, and homicides) are the leading cause of death among active duty members of the U.S. Armed Forces, accounting for about four out of five deaths. The downward trend for fatal unintentional injuries indicates the success that can be achieved when attention is focused on preventing injuries. Further reduction in injury mortality would be facilitated if collection and coding of data were standardized across the military services.

Trends in intussusception-associated hospitalizations and deaths among US infants.

CONTEXT: The newly licensed tetravalent rhesus-human reassortant rotavirus vaccine has been withdrawn following reports of intussusception among vaccinated infants. OBJECTIVE: To describe the epidemiology of intussusception-associated hospitalizations and deaths among US infants. DESIGN: This retrospective cohort study examined hospital discharge data from the National Hospital Discharge Survey for 1988-1997, Indian Health Service (IHS) for 1980-1997, California for 1990-1997, Indiana for 1994-1998, Georgia for 1997-1998, and MarketScan for 1993-1996, and mortality data from the national multiple cause-of-death data for 1979-1997 and linked birth/infant death data for 1995-1997. PATIENTS: Infants (<1 year old) with an International Classification of Diseases, Ninth Revision, Clinical Modification code for intussusception (560.0) listed on their hospital discharge or mortality record, respectively. RESULTS: During 1994-1996, annual rates for intussusception-associated infant hospitalization varied among the data sets, being lowest for the IHS (18 per 100 000; 95% confidence interval [CI] = 9-35 per 100 000) and greatest for the National Hospital Discharge Survey (56 per 100 000; 95% CI = 33-79 per 100 000) data sets. Rates among IHS infants declined from 87 per 100 000 during 1980-1982 to 12 per 100 000 during 1995-1997 (relative risk =7.6, 95% CI = 3.2-18.2). Intussusception-associated hospitalizations were uncommon in the first 2 months of life, peaked from 5 to 7 months old, and showed no consistent seasonality. Intussusception-associated infant mortality rates declined from 6.4 per 1 000 000 live births during 1979-1981 to 2.3 per 1 000 000 live births during 1995-1997 (relative risk = 2.8, 95% CI = 1.8-4.3). Infants whose mothers were <20 years old, nonwhite, unmarried, and had an education level below grade 12 years were at an increased risk for intussusception-associated death. CONCLUSIONS: Intussusception-associated hospitalization rates varied among the data sets and decreased substantially over time in the IHS data. Although intussusception-associated infant deaths in the United States have declined substantially over the past 2 decades, some deaths seem to be related to reduced access to, or delays in seeking, health care and are potentially preventable.intussusception, hospitalizations, deaths, risk factors, infants.

Firearm-related injury surveillance. An overview of progress and the challenges ahead.

Firearm-related injuries pose a serious public health problem in the United States and are increasingly the focus of public health concern. Despite the magnitude of this problem, ongoing and systematic collection of data on firearm-related injuries to help guide research and policy development has been lacking. The further development of firearm-related injury surveillance systems can provide an objective source of information for policy. Beginning in the mid-1980s, the Centers for Disease Control and Prevention's National Center for Injury Prevention and Control began to support the development of firearm-related injury surveillance systems by augmenting existing national- and state-level data collection systems and establishing cooperative agreements with state and local health departments to identify optimal firearm-related injury surveillance practices. Some progress has been made in improving the capacity to undertake firearm injury surveillance at national, state, and local levels for mortality, morbidity (including disability), and risk/protective factors, but much work remains to be done. The development of state and local firearm-related injury surveillance systems provides the clearest potential for linking basic information on firearm-related injuries to action, given the critical role that states have in both public health surveillance and regulation of firearms. Broader application of external cause-of-injury codes, increased standardization and validation of definitions and data-collection instruments, improved methods for identifying firearm characteristics and types, and the identification of efficient techniques for linking health and criminal justice data sources are among the key challenges we face as we try to build a more uniform system for monitoring firearm-related injuries in the United States.

Injury rates from walking, gardening, weightlifting, outdoor bicycling, and aerobics.

PURPOSE: The objective of this survey was to estimate the frequency of injuries associated with five commonly performed moderately intense activities: walking for exercise, gardening and yard work, weightlifting, aerobic dance, and outdoor bicycling. METHODS: National estimates were derived from weighted responses of over 5,000 individuals contacted between April 28 and September 18, 1994, via random-digit dialing of U.S. residential telephone numbers. Self-reported participation in these five activities in the late spring and summer of 1994 was common, ranging from an estimated 14.5 +/- 1.2% of the population for aerobics (nearly 30 million people) to 73.0 +/- 1.5% for walking (about 138 million people). RESULTS: Among participants, the activity-specific 30-d prevalence of injury ranged from 0.9 +- 0.5% for outdoor bicycle riding to 2.4 +- 1.3% for weightlifting. The estimated number in the 30 d of people injured in the 30 d before their interview ranged from 330,000 for outdoor bicycle riding to 2.1 million for gardening or yard work. Incidence rates for injury causing reduced participation in activity were 1.1 +/- 0.5x100 participantsx30 d for walking, 1.1 +/- 0.4 for gardening, and 3.3 +/- 1.9 for weightlifting. During walking and gardening, men and women were equally likely to be injured, but younger people (18-44 yr) were more likely to be injured than older people (45 + yr). Injury rates were low, yet large numbers of people were injured because participation rates were high. Most injuries were minor, but injuries may reduce participation in these otherwise beneficial activities. CONCLUSIONS: Additional studies to confirm the magnitude of the problem, to identify modifiable risk factors, and to recommend methods to reduce the frequency of such injuries are needed.

Identification of nearly fatal suicide attempts: Self-Inflicted Injury Severity Form.

The Self-Inflicted Injury Severity Form (SIISF) was developed as an epidemiological research tool for identifying individuals in hospital emergency departments who have life-threatening self-inflicted injuries. Data were collected from 715 patients with self-inflicted injuries in two large hospitals. In 295 of these cases, a second set of data was independently collected for assessment of interrater reliability. Validity was assessed by comparing the SIISF results with simultaneously collected Risk-Rescue Ratings. Assessment of interrater reliability found that only 2.4% of physicians disagreed on the suicide method used. The kappa statistic for method used was .94, indicating excellent agreement. The SIISF was found to distinguish between severe and less severe injuries. Thus, it appears to provide a simple method to distinguish patients who have life-threatening self-inflicted injuries.

State estimates of household exposure to firearms, loaded firearms, and handguns, 1991 through 1995.

OBJECTIVES: Variations among states in household exposure to firearms, loaded firearms, and handguns were examined. METHODS: Data from the Behavioral Risk Factor Surveillance System in 22 states were used to estimate the prevalence of adults and children exposed to household firearms. RESULTS: The prevalence of adults living in households with firearms ranged from 12% to 57%; the corresponding ranges were 1% to 23% for loaded firearms and 5% to 36% for handguns. The prevalence of children less than 18 years of age living in households with loaded firearms ranged from 2% to 12%. CONCLUSIONS: Important variations among states exist in the prevalence of adults and children living in households with firearms, loaded firearms, and handguns.

Weapon-carrying, physical fighting, and fight-related injury among U.S. adolescents.

INTRODUCTION: Access to firearms and other weapons has been cited as an important factor contributing to the rise in violence-related injury among adolescents in the United States. METHODS: Data from the Youth Risk Behavior Survey supplement to the 1992 National Health Interview Survey were analyzed to examine relationships among weapon-carrying, physical fighting, and fight-related injury among U.S. adolescents aged 12-21 years (N = 10,269). Adjusted odds ratios (OR) were used to describe the association of weapon-carrying during the past 30 days with physical fighting and fight-related injury during the past 12 months. RESULTS: Weapon-carrying (15%) and physical fighting (39%) were common among adolescents. One out of 30 (3.3%) adolescents reported receiving medical care for fight-related injuries. Controlling for demographic characteristics, youth who carried weapons were more likely than those who did not to have been in a physical fight (OR = 3.3). The association between weapon-carrying and physical fighting was stronger among females (OR = 5.0) than among males (OR = 2.9), but did not vary significantly by age, race/ethnicity, or place of residence (urban, suburban, rural). Controlling for frequency of physical fighting and demographics, adolescents who carried a handgun (OR = 2.6) or other weapon (OR = 1.6) were more likely than those who did not carry a weapon to have had medical care for fight-related injuries. CONCLUSIONS: Among adolescents, weapon-carrying is associated with increased involvement in physical fighting and a greater likelihood of injury among those who do fight. Efforts to reduce fight-related injuries among youth should stress avoidance of weapon-carrying.

Firearm-related deaths in the United States and 35 other high- and upper-middle-income countries.

BACKGROUND: The Forty-Ninth World Health Assembly recently declared violence a worldwide public health problem. Improved understanding of cross-national differences is useful for identifying risk factors and may facilitate prevention efforts. Few cross-national studies, however, have explored firearm-related deaths. We compared the incidence of firearm-related deaths among 36 countries. METHODS: Health officials in high-income (HI) and upper-middle-income countries (UMI) with populations greater than one million were asked to provide data using ICD-9 codes on firearm-related homicides, suicides, unintentional deaths and deaths of undetermined intent, as well as homicides and suicides for all methods combined. Thirty-six (78%) of the 46 countries provided complete data. We compared age-adjusted rates per 100,000 for each country and pooled rates by income group and geographical location. RESULTS: During the one-year study period, 88,649 firearm deaths were reported. Overall firearm mortality rates are five to six times higher in HI and UMI countries in the Americas (12.72) than in Europe (2.17), or Oceania (2.57) and 95 times higher than in Asia (0.13). The rate of firearm deaths in the United States (14.24 per 100,000) exceeds that of its economic counterparts (1.76) eightfold and that of UMI countries (9.69) by a factor of 1.5. Suicide and homicide contribute equally to total firearm deaths in the US, but most firearm deaths are suicides (71%) in HI countries and homicides (72%) in UMI countries. CONCLUSIONS: Firearm death rates vary markedly throughout the industrialized world. Further research to identify risk factors associated with these variations may help improve prevention efforts.

Suicide after natural disasters.

BACKGROUND: Among the victims of floods, earthquakes, and hurricanes, there is an increased prevalence of post-traumatic stress disorder and depression, which are risk factors for suicidal thinking. We conducted this study to determine whether natural disasters affect suicide rates. METHODS: From a list of all the events declared by the U.S. government to be federal disasters between 1982 and 1989, we selected the 377 counties that had each been affected by a single natural disaster during that period. We collected data on suicides during the 36 months before and the 48 months after the disaster and aligned the data around the month of the disaster. Pooled rates were calculated according to the type of disaster. Comparisons were made between the suicide rates before and those after disasters in the affected counties and in the entire United States. RESULTS: Suicide rates increased in the four years after floods by 13.8 percent, from 12.1 to 13.8 per 100,000 (P<0.001), in the two years after hurricanes by 31.0 percent, from 12.0 to 15.7 per 100,000 (P<0.001), and in the first year after earthquakes by 62.9 percent, from 19.2 to 31.3 per 100,000 (P<0.001). The four-year increase of 19.7 percent after earthquakes was not statistically significant. Rates computed in a similar manner for the entire United States were stable. The increases in suicide rates were found for both sexes and for all age groups. The suicide rates did not change significantly after tornadoes or severe storms. CONCLUSIONS: Our study shows that suicide rates increase after severe earthquakes, floods, and hurricanes and confirms the need for mental health support after severe disasters.