The widening black/white gap in asthma hospitalizations and mortality

national support of local and regional asthma coalitions.

Healthcare

education,

delivery,andqualityAsthma morbidity has even had the attention of the WhiteHouse in developing health policy to improve care and re-duce morbidity.20 Multiple strategies have been describedand shown to be cost-effective in decreasing asthma symp-toms and reducing disparities.20-22

With much attention on improving asthma care andasthma disparities, a 2003 Institute of Medicine report stillidentified asthma treatment quality as one of 20 priorityareas for national action.23 Priorities in research to reduceasthma disparities by the National Heart, Lung, and BloodInstitute were published in 2002.24

Chicago; bSmith Child Health Research Program, Childrens Memorial

Hospital, Chicago; and dMidwest Center for Health Services and Policy

Research, US Department of Veterans Affairs, Edward Hines, Jr. VA

Hospital, Hines.

Supported by Health Resources and Services Administration (HRSA) training

grant #T32HS00078-07.

Received for publication August 22, 2005; revised November 17, 2005;

accepted for publication November 29, 2005.

Reprint requests: Ruchi Gupta, MD, MPH, Institute for Healthcare Studies and

Childrens Memorial Hospital, 339 E Chicago Ave, Room 712, Chicago, IL

60611-3071. E-mail: [email protected].

0091-6749/$32.00

2006 American Academy of Allergy, Asthma and Immunologydoi:10.1016/j.jaci.2005.11.047

351Original articles

The widening black/whospitalizations and

Ruchi S. Gupta, MD, MPH,a,b Violeta Carr

Weiss, MD, MPHa,c,d Chicago and Hines, Ill

Background: Large racial differences in asthma morbidity and

mortality have prompted research on new interventions, public

awareness, and health policy efforts in the past decade.

Objective: We sought to characterize recent trends in US

asthma hospitalization and mortality for black and white

children and adults during the period from 1980 through 2002.

Methods: We conducted a successive representative national

cohort study of US residents ages 5 to 34 years using data from

the National Hospital Discharge Survey and the US vital

statistics system. Outcome measures included black/white

(B/W) asthma hospitalization and mortality rates, rate ratios,

and rate differences.

Results: For asthma hospitalizations from 1980 through 2002,

children ages 5 to 18 years had a 50% increase in the B/W rate

ratio, and the rate difference increased from 22.8 to 28.3

hospitalizations per 10,000 population. For young adults ages

19 to 34 years, the B/W rate ratio increased from 2.3 to 2.8, and

the rate difference decreased from 9.6 to 7.9 hospitalizations

per 10,000 population. For asthma mortality from 1980

through 2001, children ages 5 to 19 years had a large increase

in the B/W rate ratio from 4.5 to 5.6 and in the rate difference

from 5.6 to 8.1 deaths per 1,000,000 population. There did not

appear to be a significant change in the B/W differences for

adults ages 20 to 34 years.

Conclusions: For children, there have been notable increases in

asthma B/W differences in hospitalizations and mortality since

1980, whereas for adults the increase has been smaller. National

efforts to improve asthma care over the past decade do not

appear to have reduced this B/W gap. When treating children

with asthma, it is important to consider the racial-ethnic

factors that might lead to avoidable hospitalizations and

premature mortality. (J Allergy Clin Immunol 2006;117:351-8.)

Key words: Asthma, disparities, hospitalizations, mortality

From athe Institute for Healthcare Studies and cthe Division of General

Internal Medicine, Northwestern University Feinberg School of Medicine,hite gap in asthmamortality

ion-Carire, MA,a,c and Kevin B.

Health disparities are pervasive and have recently beenreceiving much attention.1-3 Asthma, a leading cause ofchronic illness in children and young adults,4,5 is a healthcondition characterized by substantial racial disparities.Differences in US asthma hospitalizations and mortalitywere described during the 1970s6 and more recently since1995.7 African Americans have a higher prevalence ofasthma and are 4 times more likely to be hospitalizedand 5 times more likely to die of asthma than non-African Americans.6,8-12

It is generally believed that asthma morbidity andmortality are largely preventable, especially when patientsare well educated about their disease and have access toquality health care.13,14 In 1991, the National Heart, Lung,and Blood Institute established the National AsthmaEducation and Prevention Program (NAEPP). The firstmajor task of the NAEPP was to develop national guide-lines to help improve the quality of treatment of asthma.15

There have also been a number of large-scale nationalstudies to improve inner-city asthma,16,17 programs atthe Centers for Disease Control and Prevention,18 and

19

Abbreviations usedB/W: Black/white

ED: Emergency department

ICD-9: International Classification of Disease,

Ninth Revision

ICD-10: International Classification of Disease,

Tenth Revision

NAEPP: National Asthma Education and Prevention

Program

NCHS: National Center for Health Statistics

NHDS: National Hospital Discharge Survey

J ALLERGY CLIN IMMUNOL

FEBRUARY 2006

352 Gupta, Carrion-Carire, and Weiss

Health

care

educatio

n,

delivery,andqualityTo date, there has been no study to explore whether theresearch, education, and health policy actions taken inthe 1990s have had an effect on asthma disparities. Thepurpose of this study is to characterize the trends in asthmahospitalization and mortality rates in the United States byrace for children and young adults between 1980 and2002.

METHODS

Study population

This study examines national reports of hospitalizations (hospital

discharges) and deaths (mortality data) that occurred among US

residents ages 5 to 34 years between January 1, 1980, and December

31, 2002. Hospitalization data were stratified into data on children

(ages 5-18 years) and data on adults (ages 19-34 years).Mortality data

were also stratified into data on children (ages 5-19 years) and data on

adults (ages 20-34 years). These age groups were used to minimize

misclassification of asthma caused by diagnostic uncertainty that

occurs in younger children (age

J ALLERGY CLIN IMMUNOL Gupta, Carrion-Carire, and Weiss 353

Healthcare

education,

delivery,andqualitysubjects did not change significantly between the 1980through 1984 time period (25.2 discharges per 10,000population) and the 2000 through 2002 time period(24.6 discharges per 10,000 population). The B/W rateratio for asthma hospitalizations increased from 2.8 to4 from 1980 through 2002, and the B/W rate differenceincreased from 16.3 to 18.5 discharges per 10,000population.

Most of the increase between black and white rates wasseen in children (ages 5-18 years). Asthma hospitalizationsfor white children decreased from 11.5 to 8.1 dischargesper 10,000 population between 1980 and 1984 and 2000and 2002, respectively, whereas rates for black children

increased slightly, from 34.3 to 36.5 discharges per 10,000population. The B/W rate ratio of asthma hospitalizationsfor children increased from 3.0 to 4.5 (50%), and the ratedifference increased from 22.8 to 28.3 discharges per10,000 population. The length of hospital stay for bothblack and white children similarly decreased: 3.7 to 2.4days for black children and 3.8 to 2.3 days for whitechildren between 1980 and 2002, respectively.

For adults, there was a trend toward decreasinghospitalization rates. Rates for white adults decreasedfrom 7.1 to 4.3 discharges per 10,000 population andfor black adults from 16.6 to 12.3 discharges per 10,000population between 1980 and 1984 and 2000 and 2002,

B/W rate difference 22.8 1.54* 22.1 1.53* 27.1 1.49* 30.3 1.35* 28.3 1.79*

J ALLERGY CLIN IMMUNOL354 Gupta, Carrion-Carire, and Weiss

Health

care

educatio

n,

delivery,andqualityrespectively. The B/W rate ratio and rate difference foradult asthma hospitalizations has not substantially var-ied, with the most recent (2000-2002) rate ratio of 2.8and rate difference of 7.9 discharges per 10,000 pop-ulation. The average length of stay for white adultsdecreased from 4.8 days to 2.8 days and for black

adults decreased from 4.4 days to 2.3 days between 1980and 2002.

Asthma mortality

Between 1980 and 2001, there were an average annual218 deaths from asthma in the United States in the 5- to

FIG 1. Trends in asthma hospitalization rates and rate ratios for children ages 5 to 18 years and adults ages 19

to 34 years from 1980 through 2002. Blue lines, Black subjects; yellow lines, white subjects. Crude rates of

asthma hospitalization discharges are depicted across years. Simple linear regression fits to the data across

years were done by estimating trend.FEBRUARY 2006


VOLUME 117, NUMBER 2

Gupta, Carrion-Carire, and Weiss 355

Healthcare

education,

delivery,andquality34-year age group, or 1.31 deaths per 1,000,000 popula-tion. Asthma mortality trends for persons ages 5 to 34years during this time period are presented in Table II anddisplayed in Fig 2. Unlike hospitalization, overall asthmamortality for white subjects increased from the 1980through 1984 time period to 2000 through 2001, from

2.1 to 2.6 deaths per 1,000,000 population. For black sub-jects, asthmamortality also increased during the same timeperiod from 9.9 to 13.2 deaths per 1,000,000 population.The B/W rate ratio for asthma mortality during this timeperiod increased from 4.7 to 5.0, and the rate difference in-creased from 7.8 to 10.6 deaths per 1,000,000 population.

FIG 2. Trends in asthma mortality rates and rate ratios for children ages 5 to 19 years and adults ages 19 to 34

years from 1980 through 2002. Blue lines, Black subjects; orange lines, white subjects. Crude rates of asthma

mortality are depicted across years. Simple linear regression fits to the data were done by estimating trends.


FEBRUARY 2006


Health

care

educatio

n,

delivery,andqualityChildhood asthma mortality for both black and whitechildren increased noticeably from 1980 through 2001.Mortality rates for white children increased from 1.6 in1980 through 1984 to 1.8 in 2000 through 2001.Mortality rates for black children increased from 7.2 to9.8 deaths per 1,000,000 population between 1980 and1984 to 2000 through 2001, respectively. During thesame time period, the B/W rate ratio and rate differencefor childhood asthma increased from 4.5 to 5.6 and 5.6 to8.1, respectively. This means an additional 12 deaths peryear caused by asthma for white children and an addi-tional 46 deaths per year caused by asthma for blackchildren in 2000 through 2001 compared with 1980through 1984.

Mortality for both black and white adults increasedsteadily from 1980 through 1999, with a decrease seenin the 2000 through 2001 time period. White adults hada mortality rate increase from 2.5 to 3.6 deaths per1,000,000 population between 1980 and 1984 and 2000and 2001. During the same time period, black adults alsohad an increase in mortality from 12.7 to 18.4 deaths per1,000,000 population. For young adults in the 2000through 2001 time period, the B/W rate ratio was 5.1,and the rate difference was 14.7 deaths per 1,000,000population.

DISCUSSION

From this analysis, it appears that B/W differences inasthma hospitalizations and mortality in the United Statesfor children and young adults have either remained stableor increased during the 1980 through 2002 time period.For children ages 5 to 18 years, these differences haveincreased for both hospitalization and mortality. Foryoung adults, there appears to be a smaller increase inB/W differences for hospitalizations and mortality.

With the B/W differences increasing more for childrencompared with adults, it is unlikely that there is a singleexplanation for what underlies these trends. Commonfactors thought to be associated with disparities includedifferences in prevalence of disease, access to care, qualityof care and treatment, patient education, and personalhealth beliefs and behaviors.

Pediatric asthma prevalence for both black and whitechildren increased from 1980 through 1996 but thendecreased and stabilized by 2000.29 From 1980 through1999, asthma prevalence, morbidity, and mortality in-creased among all US adults.8 Yet there are few data tosuggest that during the 1980 through 2002 time period,asthma prevalence increased more disproportionately forblack children or adults compared with white childrenor adults to explain these findings.

Access to quality medical care is to a large extentgoverned by access to health insurance. Recent increasesin health care access and use among children, especiallyamong minorities, has been demonstrated because of theState Childrens Health Insurance Program.30-32 In con-trast, more than 15 million adults without insurancehave a chronic health problem, including asthma,33 andthe number of uninsured adults is increasing. Thereforeit is likely that lack of access to insurance for adults couldbe contributing to this gap.

Beyond insurance, perhaps the largest factor associatedwith quality in asthma management is the medication usedto treat asthma. In a survey of parents of Medicaid-insuredchildren with asthma, black children had worse asthmastatus and less use of preventive medication than whitechildren.34 In private practice black children receivedfewer controller and reliever medications than white chil-dren.35 Similar to children, fewer black adults reportedcare consistent with recommendations for medicationuse than white adults.36,37 Additionally there, might bedifferences in treatment effect by race. Most notable isthe genetic variability in the b-receptor that might berelated to how black subjects have different responsive-ness to this class of medications.38 Improving asthmatreatment quality is one of 20 priority areas for nationalaction23 and could be a significant factor underlying thelack of improvement in the B/W gap seen in this study.

Asthma knowledge, health beliefs, and behaviors alsoinfluence the appropriate use of treatment and medica-tions. When parents were asked about barriers to asthmamedication use for their children, the majority reportedpersonal health beliefs, mainly misperceptions aboutasthma, asthma medications, and their use.39 Fewer blackadults reported receiving asthma self-management educa-tion.36 Asthma management education and skills trainingare vital for improved treatment and prevention ofasthma.40,41

Some factors shown to be associated with improvedasthma care include having a primary care physician, anasthma specialist, a written action plan, and a follow-upvisit42 and believing the benefits of a treatment outweighthe risks. Evidence-based asthma guidelines, such as thoseof the NAEPP,15 can be a powerful tool for reducing racialdisparities because they consist of strict explicit protocolsbased on symptoms and not race and ethnicity.43When theNAEPP guidelines are adhered to, a reduction in hospi-talizations, emergency department (ED) visits, and out-patient asthma visits has been demonstrated.44 Althoughthese guidelines, along with other interventions, mightbe contributing to the overall decrease in hospitalizationseen in our study, it is not apparent how this would affectthe B/W gap.

A recent study looking at asthma health disparities since1995 found a reduction in the disparities gap betweenblack andwhite adults and children.7 The study looked at anarrower time frame, men and women separately, andpatients from less than 1 to 74 years old. Discrepanciesin the diagnosis of asthma are known to exist for childrenless than 5 years of age because of misdiagnosis and con-fusion with transient early wheezing25 and with adultsgreater than 35 years of age because of misclassificationof asthma with chronic obstructive pulmonary disease inolder adults.10 The differences in the study age categoriesand years analyzed might account for the differences inour results.


VOLUME 117, NUMBER 2

Gupta, Carrion-Carire, and Weiss 357

Healthcare

education,

delivery,andqualityThere are, as with all studies, limitations to the designthat need to be highlighted. The NHDS, unlike the vitalrecords, describe events and person-based experience.Also, the source of the data on race for both hospitaliza-tion and mortality data is not known. For example, it isnot possible with the hospital data to know whether thepatient, family, nurse, administrator, or physician re-corded the patients race and, ultimately, whether it wasdetermined by self-report or observation. We were alsounable to detect repeat hospitalizations by the samepatient, and the race variable was missing in 18.51% ofthe NHDS database. Although the NHDS hospital sampleis designed to provide national estimates of inpatienthospital use, it is potentially feasible that ED practices,such as 23-hour ED short stays (observation units), mightnot be uniformly deployed at all hospitals and thereforemight not be optimally represented in the NHDS hospitalsample. For mortality records, the origin of race data isalso not well characterized.

On the basis of the recent trends in asthma hospitali-zation and mortality, reducing disparities in asthma careshould be a national priority for research, health policy,and community action.2,20,24 Black and white childrenages 5 to 18 years had the largest increases in differencesfor both asthma hospitalizations and mortality over thepast 2 decades, with adults having a slight increase or sta-bilization. Different issues might be driving the relativelylarge increase in asthma disparities for children comparedwith adults. Further understanding of the reasons for thesedifferences and strategies to eliminate them might start toclose this unacceptable B/W gap.

We thank Ramon A. Durazo-Arvizu, PhD, and Christopher S.

Lyttle, MA, for their statistical expertise in this study.

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Health

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educatio

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delivery,andquality

The widening black/white gap in asthma hospitalizations and mortalityMethodsStudy populationHospitalization dataMortality dataCase definitionRace classificationStatistical considerations

ResultsAsthma hospitalizationsAsthma mortality

DiscussionReferences

Documents

The widening black/white gap in asthma hospitalizations and mortality