Trends in childhood asthma: NCHS data on prevalence, health care use and mortality

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Trends in childhood asthma NCHS data on
prevalence, health care use and mortality

• Susan Lukacs, DO, MSPH
• Lara Akinbami, MD
• Infant, Child and Womens Health Studies Branch,
  NCHS, CDC

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Asthma data available from NCHS data systems

• Prevalence
• Health care utilization
• Ambulatory health care
• Hospitalizations
• Mortality

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Asthma prevalence
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National Health Interview Survey (NHIS)

• Continuous multipurpose survey on health
  conditions, status and behavior
• Representative sample of the noninstitutionalized
  civilian US population
• Interviews in gt40,000 households no review of
  medical records
• Parent or responsible adult answers in proxy for
  children under 18 years of age
• Redesigned in 1997 affected asthma estimates

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NHIS original and redesigned asthma questions
1980-1996 Redesigned 1997-present Additional question 2001-present
Screener question (None) Has a doctor or other health professional EVER told you that your child had asthma?
Prevalence questions During the past 12 mos, did anyone in the family have asthma? IF YES to EVER? During the past 12 mo, has your child had an episode of asthma or an asthma attack? IF YES to EVER? Does your child still have asthma?
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Asthma prevalence, 1980-96, asthma lifetime
diagnosis, current and asthma attack prevalence,
1997-2002 NHIS, children 0-17 years
Asthma lifetime diagnosis
Current asthma prevalence
Asthma prevalence (4.3 per yr ?)
Asthma attack prevalence
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Other asthma indicators available from the NHIS

• 2002 asthma module
• School days missed (trend established prior to
  1997)
• Preventive medications
• Given asthma management plan by doctor
• Advised by doctor to change home environment
• 1999 asthma module (different questions)
• Wheezing severity
• Use of OTC and prescription medications

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Average number school days a child with asthma
missed per year, ages 5-17 years NHIS 1980-2002
NHIS redesign

• Per child with asthma having gt one asthma attack
  per year

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Indicators of asthma control among children with
current asthma, 2002 NHIS asthma module
Ever taken preventive medication 65
Given management plan by MD 40
Advised to change environment by MD 48
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Asthma hospitalizations
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Asthma hospitalizations for children 0-17 years,
1980-2002 National Hospital Discharge Survey
(NHDS)
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Asthma mortality
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Mortality component of National Vital Statistics
System (NVSS)

• Death certificate data received by NCHS from 50
  States and DC ? can obtain State-level data
• Coding system changed in 1999 from ICD-9 to
  ICD-10

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Asthma deaths, children 0-17 years, 1980-2000,
NVSS
ICD-9
ICD-10
ICD-9
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Race/ethnic disparities in the burden of
childhood asthma

• Healthy People 2010 overarching goal
• Examining disparities in asthma can guide policy
  and program decisions
• However, issues in categorizing by race
• New OMB guidelines single vs. multiple race
• Ethnicity not consistently available in data
  systems that rely on abstraction from medical
  records

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Race/ethnic disparities in asthma attack
prevalence, (1997-2001 annual average), NHIS
Non-Hispanic black
Non-Hispanic black children had 30 higher asthma
attack prevalence than NH white children
Non-Hispanic white
Hispanic
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Race/ethnic disparities in asthma attack
prevalence, (1997-2001 annual average), NHIS
Puerto Rican
Non-Hispanic black
Non-Hispanic white
Hispanic
Mexican
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Racial disparities in asthma hospitalizations
(2000-2002 annual average), NHDS
Black
Black children had 240 higher hospitalization
rate than white children
White
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Race/ethnic disparities in mortality (1999-2001
annual average), NVSS
Non-Hispanic black
Non-Hispanic black children had 350 higher
asthma death rate than NH white children
Non-Hispanic white
Hispanic
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Summary on trends in childhood asthma

• Prevalence, health care use, and mortality
  increased through the mid 1990s
• Since the mid 1990s, prevalence, ambulatory
  health care use, hospitalization and death rates
  have plateaued
• Minority children bear a higher asthma burden
• Racial disparities are most pronounced for
  preventable outcomes, such as ER visits,
  hospitalization and death

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For additional information on asthma from the CDC

• NCHS home page http//www.cdc.gov/nchs/
• Asthma Health E stat asthma prevalence, health
  care use and mortality for all ages in 2002
• Summary statistics from the NHIS for children,
  2002
• National Center for Environmental Health
  http//www.cdc.gov/nceh/airpollution/asthma/
• Behavioral Risk Factor Surveillance Survey state
  level asthma prevalence for adults
• Links to asthma-related reports in the Morbidity
  and Mortality Weekly Report, including the Asthma
  Surveillance Summary, 1980-1999