Deborah Azrael1, Alexander Mukamal2, Amy P Cohen3, David Gunnell4, Catherine Barber3, Matthew Miller5. 1. Harvard Injury Control Research Center, Harvard T.H. Chan School of Public Health, Boston, Massachusetts; Bouve School of Health Sciences, Northeastern University, Boston, Massachusetts. Electronic address: azrael@hsph.harvard.edu. 2. Harvard Injury Control Research Center, Harvard T.H. Chan School of Public Health, Boston, Massachusetts; Yale College, Yale University, New Haven, Connecticut. 3. Harvard Injury Control Research Center, Harvard T.H. Chan School of Public Health, Boston, Massachusetts. 4. Bouve School of Health Sciences, Northeastern University, Boston, Massachusetts. 5. Harvard Injury Control Research Center, Harvard T.H. Chan School of Public Health, Boston, Massachusetts; School of Social and Community Medicine, Faculty of Medicine and Dentistry, University of Bristol, Bristol, United Kingdom.
Abstract
INTRODUCTION: Identifying the source and specific type of gas used in suicides is difficult using most data systems owing to limitations in ICD-10 coding. The National Violent Death Reporting System (NVDRS), with its rich collection of both coded and free-text variables, has the potential to overcome these limitations. This study used a multipronged approach to identify gas-specific suicides in NVDRS and to track the incidence of these suicides over time. METHODS: Using suicide cases from the 16 NVDRS states that participated throughout 2005-2012, free-text and code searches were conducted for four types of variables-incident narratives, coroner/medical examiner cause-of-death statements, cause-of-death codes, and substance names-to identify suicides by carbon monoxide, helium, hydrogen sulfide, and four other gases. All analyses were conducted in 2015. RESULTS: Approximately 4% (3,242 of 80,715) of suicides recorded in NVDRS over the study period were the result of gas inhalation. Of these, the majority (73%) were carbon monoxide suicides (almost exclusively from motor vehicle exhaust and charcoal burning). Other types of gas (most notably helium), once rare, are now more common: At the start of the study period non-carbon monoxide gas suicides represented 15% of all gas suicides; at the end of the study period, they represented 40%. CONCLUSIONS: Public health policies to reduce a suicidal person's access to more lethal suicide methods require a reliable source of surveillance data on specific methods used in suicide. Small changes to NVDRS could make it an efficient and nimble surveillance system for tracking these deaths.
INTRODUCTION: Identifying the source and specific type of gas used in suicides is difficult using most data systems owing to limitations in ICD-10 coding. The National Violent Death Reporting System (NVDRS), with its rich collection of both coded and free-text variables, has the potential to overcome these limitations. This study used a multipronged approach to identify gas-specific suicides in NVDRS and to track the incidence of these suicides over time. METHODS: Using suicide cases from the 16 NVDRS states that participated throughout 2005-2012, free-text and code searches were conducted for four types of variables-incident narratives, coroner/medical examiner cause-of-death statements, cause-of-death codes, and substance names-to identify suicides by carbon monoxide, helium, hydrogen sulfide, and four other gases. All analyses were conducted in 2015. RESULTS: Approximately 4% (3,242 of 80,715) of suicides recorded in NVDRS over the study period were the result of gas inhalation. Of these, the majority (73%) were carbon monoxide suicides (almost exclusively from motor vehicle exhaust and charcoal burning). Other types of gas (most notably helium), once rare, are now more common: At the start of the study period non-carbon monoxide gas suicides represented 15% of all gas suicides; at the end of the study period, they represented 40%. CONCLUSIONS: Public health policies to reduce a suicidal person's access to more lethal suicide methods require a reliable source of surveillance data on specific methods used in suicide. Small changes to NVDRS could make it an efficient and nimble surveillance system for tracking these deaths.