National Surveillance Estimates of Unintentional, Non-fire Related

Carbon Monoxide Poisoning

Jackie Clower, MPHContractor, Air Pollution & Respiratory Health Branch

June 13, 2011

National Center for Environmental HealthDivision of Environmental Hazards and Health Effects

CARBON MONOXIDE (CO)

Colorless, odorless gas

Produced due to incomplete combustion of hydrocarbons

Common routine sources: Home heating & cooking appliances Gas powered equipment Motor vehicles

A leading cause of poisoning in the US

EPIDEMIOLOGY OF UNINTENTIONAL, NON-FIRE-RELATED EXPOSURES

Mortality & Morbidity >20, 000 emergency department visits ~450 deaths

Populations Non-fatal: Children (<5 years), Females Fatal: Elderly (>65 years), Males

Season Winter

Region Midwest Northeast

HEALTH EFFECTS & PREVENTION Non-specific flu-like symptoms:

Fatigue, dizziness, headache, confusion, nausea, vomiting

Collapse, coma, cardio-respiratory failure, & death 15−49% develop neuro-cognitive sequelae

Most cases: Occur in residential settings Preventable with installation of CO alarms

CO SURVEILLANCEFrequency of eventsSeverity of outcomePreventability of exposures

+ Effectiveness of simple preventive measures

= Critical Issue for Public Health Surveillance

CDC developed a national surveillance framework for unintentional, non-fire related CO poisoning from several data sources

CO SURVEILLANCE FRAMEWORK

Mortality

Hospitalization

Hyperbaric oxygen treatment

Emergency department visits

Poison center

National Fire Protection Association

Health Behaviors(e.g., presence of CO alarm at home)

National Vital Statistics System– ~ 450 deaths annually (1999 –2004)

Nationwide Inpatient Sample, 2007– ?

Nationwide Emergency Department Sample, 2007 – ?

Hyperbaric Oxygen , 2009 – ?

American Housing Survey, 2009– 33.4% U.S. households with working CO alarmNational Health Interview Survey, 2009– 40.3% U.S. households with CO alarm

National Poison Data System– ? (2000 – 2009)National Fire Protection Association, 2005 – 61,100 non-fire CO incidents

CO HOSPITALIZATIONSAND ED VISITS: METHODS

Healthcare Cost and Utilization Project (HCUP)

Sponsored by Agency for Healthcare Research and Quality

Largest data repository of hospital discharges Short-term, non-federal, general hospitals Nationally representative samples are drawn

CO HOSPITALIZATION AND ED VISITS: METHODS

Characteristics NEDS 2007

NIS 2007

Participating states 27 40Sample hospitals 966 1,044Sample discharge ~27 mill >8 millTotal weighted sample >122 mill >39 mill

HCUP: Nationwide Emergency Department Sample (NEDS) Nationwide Inpatient Sample (NIS)

CSTE’s case definition used to classify confirmed, probable, & suspected cases

Rates were calculated with Census Bureau population estimates

CO HOSPITALIZATION AND ED VISITS: RESULTS

Highest rate of ED visits among those 18-44 years (87 visits/million)

Highest rate of hospitalization among those ≥85 years (18 stays/million)

Females visited EDs more than males Males more likely to be hospitalized CO-related hospitalization cost was >$26 million

NEDS 2007 NIS 2007

n (%) Rate per million (95% CI)

n (%) Rate per million (95%

CI)Total CO Cases

232,875 772 (764,781) 22, 718 75 (67, 84)

Confirmed CO Cases

21,304 (9.1)

71 (69,72) 2,302 (10.1)

8 (6,9)

CO SURVEILLANCE FRAMEWORK

Mortality

Hospitalization

Hyperbaric oxygen treatment

Emergency department visits

Poison center

National Fire Protection Association

Health Behaviors(e.g., presence of CO alarm at home)

National Vital Statistics System– ~ 450 deaths annually (1999 –2004)

Nationwide Inpatient Sample, 2007– 2,302 confirmed cases

Nationwide Emergency Department Sample, 2007 – 21,304 confirmed cases

Hyperbaric Oxygen , 2009 – ?

American Housing Survey, 2009– 33.4% U.S. households with working CO alarmNational Health Interview Survey, 2009– 40.3% U.S. households with CO alarm

National Poison Data System– ? (2000 – 2009)National Fire Protection Association, 2005 – 61,100 non-fire CO incidents

HYPERBARIC OXYGEN TREATMENT: METHODS

Database of hyperbaric oxygen treatments administered for severe CO poisoning

Undersea and Hyperbaric Medical Society (UHMS) physicians contribute data on patients receiving treatment

August 2008 - January 2010: patient-level data were reported by 87 facilities in 39 states

Case definition: an individual treated with hyperbaric oxygen at a participating facility in the US

HYPERBARIC OXYGEN TREATMENT: METHODS

Panel of 38 questions: Patient demographics Treatment regimens Circumstances surrounding poisonings

Example variables: Number of others treated with hyperbaric oxygen in the same

incident Duration of exposure Symptoms Duration of loss of consciousness % blood carboxyhemoglobin

HYPERBARIC OXYGEN TREATMENT: RESULTS

Among the 864 patients, most were: White (54.3%) Male (57.3%) Aged 18 -44 years (43.5%)

75% exposed along with others 55% of patients were discharged after

treatment 41% were hospitalized

10% of patients reported a CO alarm at their exposure location

CO SURVEILLANCE FRAMEWORK

Mortality

Hospitalization

Hyperbaric oxygen treatment

Emergency department visits

Poison center

National Fire Protection Association

Health Behaviors(e.g., presence of CO alarm at home)

National Vital Statistics System– ~ 450 deaths annually (1999 –2004)

Nationwide Inpatient Sample, 2007– 2,302 confirmed cases

Nationwide Emergency Department Sample, 2007 – 21,304 confirmed cases

Hyperbaric Oxygen , 2009 – 552 cases

American Housing Survey, 2009– 33.4% U.S. households with working CO alarmNational Health Interview Survey, 2009– 40.3% U.S. households with CO alarm

National Poison Data System– ? (2000 – 2009)National Fire Protection Association, 2005 – 61,100 non-fire CO incidents

POISON CENTER CALLS: METHODS Nationally, 61 Poison Centers upload call

data to the National Poison Data System (NPDS)

2.2 million reports annually Includes 36 million reports over last 30

years Case definition:

A call: Regarding a human CO exposure Coded as “unintentional” exposure

Example variables: Demographics Call type: informational vs. exposures Clinical effects: symptoms Exposure site Level of care Outcome

POISON CENTER CALLS: RESULTS 68,316 (23 calls/million/year) CO exposure calls to US poison centers from 2000-2009

28% of calls was regarding persons <18 years (18,896)

50% (34,356) of women & 44% of men (30,257) reported being exposed

235 deaths captured

NPDS provides data regarding CO exposed populations who would not be captured by administrative health records 53.7% (36,691) managed at a healthcare facility 45.1% (30,798) managed onsite & not otherwise

identified

CO SURVEILLANCE FRAMEWORK

Mortality

Hospitalization

Hyperbaric oxygen treatment

Emergency department visits

Poison center

National Fire Protection Association

Health Behaviors(e.g., presence of CO alarm at home)

National Vital Statistics System– ~ 450 deaths annually (1999 –2004)

Nationwide Inpatient Sample, 2007– 2,302 confirmed cases

Nationwide Emergency Department Sample, 2007 – 21,304 confirmed cases

Hyperbaric Oxygen , 2009 – 552 cases

American Housing Survey, 2009– 33.4% U.S. households with working CO alarmNational Health Interview Survey, 2009– 40.3% U.S. households with CO alarm

National Poison Data System– 68,312 exposure calls (2000 – 2009)National Fire Protection Association, 2005 – 61,100 non-fire CO incidents

SUMMARY AND CONCLUSIONS

These analyses expand CO surveillance to include: Most comprehensive, recent national estimates of ED

visits & hospitalizations Most detailed information on patients treated with

hyperbaric oxygen First summary that includes a 10-year period of poison

center calls

Findings from this surveillance framework are critical for prevention efforts as the results contribute to a better understanding of CO poisoning

ACKNOWLEDGEMENTS:Shahed IqbalJeneita BellFuyuen Yip

For more information please contact Centers for Disease Control and Prevention

1600 Clifton Road NE, Atlanta, GA 30333Telephone: 1-800-CDC-INFO (232-4636)/TTY: 1-888-232-6348E-mail: cdcinfo@cdc.gov Web: http://www.cdc.gov

The findings and conclusions in this report are those of the authors and do not necessarily represent the official position of the Centers for Disease Control and Prevention.

National Center for Environmental HealthDivision of Environmental hazards and Health Effects