How do we and how should we define and count poisoning deaths in the United States?

1. U.S. DEPARTMENT OF HEALTH AND HUMAN SERVICES Centers for Disease Control and Prevention National Center for Health Statistics How do we and how should we define and count poisoning deaths in the United States? Lois A. Fingerhut, MASpecial Assistant for Injury Epidemiology, OAERobert N. Anderson, PhDChief, Mortality Statistics Branch, DVS

2. Objectives • To consider revising the existing matrix definition of poisoning to include relevant codes from the F10-F19 series of the Mental and Behavioral Disorders chapter of the ICD • To better understand what is gained from analyzing multiple cause of death data for poisoning

3. How are poisoning deaths currently defined? • By the List of 113 Causes (used to rank leading causes of death in the US): the underlying cause ICD-10 codes for Unintentional poisoning are X40-X49 • By the External Cause of Injury Mortality Matrix as the underlying cause for poisoning regardless of intent [Recommended by NCHS and Injury ICE]

4. Poisoning is defined in the Matrix by ICD-10 codes by intent ICD also codes broad substance groups

5. Poisoning deaths- 2002

6. Based on the matrix definition, poisoning was, in 2002,… • 3rd leading cause of injury death overall; • distant 2nd for unintentional injury; • 3rd for suicide • leading cause for intent undetermined.

7. Should codes be added to the definition of poisoning? • Being considered are underlying ICD-10 codes F10-F19 for Mental and Behavioral disorders (MBD) due to pyschoactive substance use • The precise wording on the death certificate can determine whether a drug or alcohol related death is assigned an underlying cause of poisoning or a F10-F19 code.

8. F10 Alcohol F11Opioids F12 Cannabinoids F13 Sedatives/hypnotics F14 Cocaine F15 Other stim.,incl. caffeine F16 Hallucinogens F17 Tobacco F18 Volatile solvents F19 Mult drug use & other psycho. substances 4th digit of these codes: .0 Acute intoxication .1 Harmful use .2 Dependence syndrome .3-.4 Withdrawal states .5 Psychotic disorder .6 Amnesic syndrome .7 Residual/late onset psychotic disorder .8 Other MBD .9 Unspecified MBD F10-F19: If so, which codes should be added? 3 digit ICD-10 codes For each 3 digit code: .0-.1 and .3-.9= Nondependent abuse .2=Dependent abuse

9. F10-F19 Deaths: 2002 [MBD due to tobacco use (F17) is not included as a drug. F17 was the underlying cause of 549 deaths in 2002.]

10. Alcohol and drug-related deaths from MBD 1999-2002 Slow but steady increases in alcohol-related (except intoxication) deaths as well as nondependent drug abuse deaths

11. Multiple cause codes identify the specific drug or substance • Multiple cause of death codes are often referred to as nature of injury codes; for poisoning and toxic effects in ICD-10 these are T36-T65. • Too often they are neglected in analyses.

12. “T” codes • T36-T50: Poisoning by drugs, medicaments and biological substances • T51-T65: Toxic effects of substances chiefly nonmedicinal as to source • Using these nature of injury poisoning codes, 29,974 deaths had at least one mention of a poison or toxic substance, and there were a total of 49,946 mentions of substances. • For all underlying-external cause poisoning deaths, an average of 1.9 total substances were listed per death

13. Leading substances in multiple cause data by underlying cause of death : 2002 Underlying causes of death Drugs and toxic effect substances mentioned in multiple cause data

14. WHO’s Mortality Reference Group (MRG) • The MRG makes decisions regarding the application and interpretation of ICD to mortality and makes recommendations on proposed ICD updates to the Update Reference Committee (URC). • The URC recommends changes to the ICD-10 to the Heads of WHO Collaborating Centers for the Family of International Classifications each year.

15. The MRG has recommended: Deaths due to Acute Intoxication • If the death certificate has language that includes words that would have resulted in an underlying cause code of F10-F19 with a 4th digit of ‘0’, the new rule will result in coding to an underlying external poisoning code for alcohol. • The largest impact in the US will be more deaths coded to X45 [Accidental poisoning by and exposure to alcohol] because nearly all of the F10-F19 codes with a 4th digit of ‘0’ are for alcohol (F10.0)

16. Regarding all F10-F19: • If the underlying cause would have resulted in any code F10-F19 and the certificate also included information ascribed to an external cause poisoning code, the new rule will result in underlying cause codes going to the external causes. • These changes will increase the number of poisoning deaths by an indeterminate amount. • These changes will be implemented in 2006.

17. Recommendation • At a minimum, consider expanding the definition of poisoning deaths beyond the number based on matrix (26,435 deaths in 2002) to include deaths due to alcohol intoxication (617 deaths), and deaths due to drug non-dependence (1,747)

18. 3 leading causes of injury death: 2002 Will poisoning soon become the 2nd leading cause of injury death??

19. Conclusion • Death certificate wording determines whether a drug or alcohol-related death is assigned an underlying cause of poisoning or mental or behavioral disorder. Recommendations on formal definitions must follow broad-based discussions among communities of toxicologists, medical examiners, and injury epidemiologists.

20. National Academy of Science May 2004 U.S. Institute of Medicine has recommended that: • WHO should review and reform the ICD codes for poisoning[This is being done] • NCHS should review the methodology of its existing surveys to maximize the value….for poison prevention and control.[Review of mortality definition is underway] From: Forging a Poison Prevention and Control System (2004)

21. LFingerhut@cdc.gov RNAnderson@cdc.gov