May 27, 2010

Emergency Department Visits for Drug-related Suicide Attempts by Adults Aged 25 or Older: 2008

In response to the devastating impact that suicide has on families and communities, the U.S. Surgeon General issued a public health call to action for suicide prevention in 1999.¹ However, research that examined suicides between 1986 and 2005 showed that the overall suicide rate declined an average of 1.2 percent each year between 1986 and 1999 and then increased an average of 0.7 percent between 1999 and 2005.² The increase between 1999 and 2005 was caused primarily by the increased suicide rates among white persons aged 40 to 64, a demographic not commonly perceived as high risk. Specifically, suicide rates during this time period increased in this age group by 2.7 percent annually for white men and 3.9 percent annually for white women.

Completed suicides represent only part of this public health problem. Suicide attempts remain one of the most important risk factors for completed suicides.³ Emergency department (ED) data provide a window into recent trends for suicide attempts that were serious enough to necessitate emergency treatment. Between 1992 and 2001, there was a 47 percent increase in all suicide attempts.⁴ More recent data from the Drug Abuse Warning Network (DAWN) show that the number of ED visits for drug-related suicide attempts increased 21 percent from 2005 to 2006, with the most recent estimates leveling off in 2007 and 2008.⁵

The DAWN data provide a way to monitor drug-related ED visits in the United States.^6,7 To be a DAWN case, the ED visit must have involved a drug, either as the direct cause of the visit or as a contributing factor. DAWN data can be used to examine ED visits for drug-related suicide attempts. Although DAWN includes only suicide attempts that involve drugs or alcohol in combination with drugs, these attempts are not limited to drug overdoses. If there is drug involvement in a suicide attempt by other means (e.g., cut wrists while smoking marijuana), the case is included as drug related. Excluded are suicide attempts with no drug involvement and suicide-related behaviors other than actual attempts (e.g., suicidal ideation or suicidal thoughts); also excluded are suicide attempts involving alcohol only for patients aged 21 or older. This issue of The DAWN Report focuses on ED visits resulting from drug-related suicide attempts by adults aged 25 or older; other reports in this series focus on visits involving suicide attempts among other age groups.

During 2008, an estimated 3,224,014 drug-related ED visits were made by patients aged 25 or older, of which 4.3 percent (138,108 visits) involved a suicide attempt. Many of the ED visits for drug-related suicide attempts involved multiple drugs, with an overall average of 2.4 drugs per ED visit for both males and females. More than half (57.7 percent) of the ED visits for drug-related suicide attempts were made by females.

Almost two thirds of the ED visits for drug-related suicide attempts by adults aged 25 or older were made by patients in the 25 to 34 and 35 to 44 age groups (31.8 and 30.9 percent, respectively), and one quarter of the visits were made by patients aged 45 to 54 (24.6 percent) (Figure 1). About one in eight visits (12.6 percent) were made by patients aged 55 or older.

Figure 1. Percentage of Emergency Department (ED) Visits for Drug-related Suicide Attempts by Adults Aged 25 or Older, by Age Group: 2008

Pharmaceuticals were involved in 94.9 percent of ED visits for drug-related suicide attempts among adults aged 25 or older (Table 1). Alcohol in combination with other drugs was involved in one third (32.8 percent) of all visits. Illicit drugs were involved in about one fifth (19.1 percent) of these visits, with 12.3 percent involving cocaine and 7.2 percent involving marijuana.⁸

Anti-anxiety drugs were involved in 45.3 percent of ED visits for drug-related suicide attempts, the majority of which could be attributed to benzodiazepines (33.6 percent). Antidepressants were involved in 21.0 percent of these visits, while antipsychotics accounted for 13.6 percent. Narcotic painkillers accounted for 15.4 percent of such visits, while pain medications containing acetaminophen as their main ingredient were involved in 10.7 percent, and anticonvulsants accounted for 7.5 percent of these ED visits. Cardiovascular agents were involved in 8.0 percent of these ED visits. Other prescription and over-the-counter (OTC) pharmaceuticals, including gastrointestinal agents (e.g., laxatives) and respiratory agents (e.g., antihistamines), involved in ED visits for drug-related suicide attempts among adults aged 25 or older were typically found at rates of less than 5 percent (data not shown).

The drugs involved in ED visits for drug-related suicide attempts varied by gender. Anti-anxiety drugs were more likely to be involved in visits made by females than those made by males (49.4 vs. 39.6 percent), as were antidepressants (23.4 vs. 17.7 percent) (Figure 2). Conversely, ED visits involving drug-related suicide attempts by males were more likely than those by females to involve alcohol in combination with other drugs (38.4 vs. 28.7 percent) and illicit drugs (25.0 vs. 14.7 percent). Antipsychotics and narcotic painkillers each were involved in more than 1 in 10 ED visits made by males (13.5 and 14.4 percent, respectively) and females (13.8 and 16.2 percent, respectively).

Figure 2. Selected Substances Involved in Emergency Department (ED) Visits for Drug-related Suicide Attempts by Adults Aged 25 or Older, by Gender: 2008

The drugs involved in ED visits for drug-related suicide attempts also varied by age group (Table 2). Anti-anxiety drugs accounted for the largest proportions of substances involved with these visits across all age groups (ranging from 41.7 to 62.0 percent). Anti-anxiety drugs were involved in approximately 6 in 10 of such visits among patients aged 55 to 64 and 65 or older (58.4 and 62.0 percent, respectively). Of these, benzodiazepines were involved in more than one third (37.3 percent) of such visits made by patients aged 55 to 64 and in more than half (50.7 percent) made by patients aged 65 or older. About one third of visits among patients in the 25 to 34, 35 to 44, and 45 to 54 age groups involved alcohol in combination with other drugs (31.8, 36.4, and 34.0 percent, respectively), compared with about one quarter (25.9 percent) of visits among patients aged 55 to 64 and about one fifth (19.9 percent) of those for patients aged 65 or older. Nearly one quarter (24.2 percent) of visits among patients aged 35 to 44 involved illicit drugs, with smaller percentages for other age groups. Antipsychotic drugs accounted for more than one in five visits among patients aged 65 or older (21.5 percent). Smaller percentages of visits involved narcotic painkillers (e.g., hydrocodone and oxycodone products), ranging from 13.2 percent among patients aged 65 or older to 16.9 percent among patients aged 55 to 64.

While suicide prevention efforts have historically targeted youths, young adults, and elderly men, the findings in this report suggest that adults aged 25 to 54 may also be appropriate targets for drug-related suicide prevention campaigns. The patterns of drug involvement for persons of different ages and genders suggest that interventions might be most effective if they are tailored to match the behaviors and needs of specific groups. Moreover, given the high involvement of prescription drugs in ED visits for drug-related suicide attempts made by patients aged 25 or older, doctors and families need to be educated about the potential use of prescription drugs as a method of or influence on suicide attempts.