Asthma-Related Medical Expenditures
                        in me United States:
                     Distributions and Trends
                OCHP Paper Series on Children's
                   Health  and the Environment
                             Paper 2QO3-4
         Prepared by Lauraine G. Chestnut and David M. Mills of Stratus Consulting Inc.
                                July  2003
•
    Disclaimer
    This paper is being distributed for purposes of information sharing and discussion only. The
    opinions and findings expressed in this paper arc those of the authors and do not necessarily rep-
    resent those of the U.S. Environmental Protection Agency or of the Office of Children's Health
    Protection. No official endorsement should be inferred from the paper.
                     MEDICAL EvpENnt-JPSS lii *HF U^iT-D aT4TES: DiS*FI3:j"iON3 A\'B

-------
About me  Paper  Series
The Office of Children's Health Probiction (OCHP) at the U.S. Environmental Protection Agency
(EPA) has created ihe Paper Series an Children's HeaWi and the Environment to share scientific, regula-
tory, and policy information about children's health and the environment with a broad audience.

The Paper Series is comprised of papers written by EPA staff members and external researchers
receiving funding from OCHP. Each paper must receive an approval from OCHP prior to accept-
ance in the Scries and undergo technical peer reviews by experts from both in and outside EPA.

All papers in the Series are distributed for purposes of information sharing and discussion only.
The opinions and findings expressed in these papers are those of the authors and do not neces-
sarily represent tho.se of l.ho U.S. Environmental Protection Agency or of the Office of Children's
Health Protection. No official Agency endorsement should be inferred from the papers.

For more information ntxiut the Paper Series, including submissions and questions, pleasv contact
Edward H. Chu at (202) 564-2188 or chu.ed@epa.gov
    ASTHk'4-RELATED tfE?:CAL EXPENDITURES IN THE UN:TED STATES' DISTRIBUTIONS 4N& TRENDS    |

-------
Ackno wled s'ment s
This paper, th«? fourth in the Office of Children's Health Protection's Paper Series on Children's
Health and the Environment, examines medical care expenditures for asthma in the United States.
The paper also compares asthma-related prescription medicine expenditure estimates based on
Medical Expenditure Payment Survey data to estimates. bitsed on an evaluation of what expendi-
tures would be if recommended treatment guidelines were followed (U.S. EPA, 1999).

Many individuals assisted in preparing this paper. OCHP appreciates the comments and guid-
ance of the following internal EPA peer reviewers: Lanelle Wiggins, Nicole Owens, Nathalie
Simon, Ed Chu, and Mark Heil.  Helpful comments were provided  by Dr.  Kevin Weiss of
Northwestern University  and  Stephen Redd  of  the U.S.  Centers for Disease  Control  and
Prevention.
ASTHM4-RFS.ATED MEPiCAi.
                                    IN TI-JE UN:TED STATES OlSTPiB'jTiONS AND TRENDS    ij|

-------
lame  or  Contents
    1. Introduction  	1




    2. Data Sources and Methods	3




    3. Asthma-Rotated Medical Service Use and Expenditure Estimates for 1996  	4




      3.'I     Total Asthma-Related Medical Expenditures	4




      3.2     Distribution of Asthma-Related Medical Expenditures	5




      3.3     Sources of Payment for Asthma-Related Medical Care	6




      3.4     Comparison to Another Estimate of Asthma-Related Medical Expenditures .  .7




    4. Trends in Asthma and Asthma-Related Medical Expenditures 	9




      4.1     C?hai\gcs in Expenditures Since the 1980s	9




      4.2     Prescription Medicine Usage for Asthma	10




    5. Summary	12




    References  	14
   jy    >'>S*H!V
-------
            Introduction
Asthma is a chronic respiratory- disease that
causes periodic episodes of inflammation and
obstruction in the airways. Symptoms include
coughing, wheezing, tightness in  the chest,
and shortness of breath. In its  most severe
manifestations it can cause death. The reasons
why certain individuals develop asthma are
not well understood, but it is well document-
ed that  for some individuals  symptoms are
aggravated by exposure to allergens, air pol-
lutants, cold temperatures, respiratory illness,
and exercise.

There are several sources of information about
the: number of  people with asthma in the
United Stales, but the specific numbers vary
depending on how it is defined. Recent esti-
mates suggest that overall about 5  percent of
the U.S. population has asthma, with a some-
what higher rale (6 percent to 7 percent) in
children under age 18 (NCHS, 1998) Once a
person develops asthma there Is no cure, but
some individuals seem, to "grow out of it" or
no longer have symptoms after some period
of time. Therefore, questions that ask, "Have
you ever been told by a doctor that you have
asthma?"  obtain the highest  estimates but
tend to overstate the population with current-
ly active asthma.

Recent change's in the w,iy the asthma preva-
lence questions are asked in  the National
Health Interview Survey (NH1S), which is con-
ducted annually, illustrate how the estimates
of asthma prevalence can vary. Table 1 shows
several  different estimates of asthma preva-
lence in the United States. The first row shows
estimates of the number of Individuals who
report any medical care expenditure for asth-
ma in 19%. This defines the lowest rate of asth-
ma at 3.2 percent and clearly understates the
number of people with asthma to the extent
that some have symptoms but seek no medical
treatment. The second row shows an estimate
of the number who report that they had asth-
ma in the past year. This is about 5.5 percent of
Table 1. Number of People With Asthma
Definition of Having Asthma Under 18 jRow %}
Asthma-related
medical care. 1996* 3,188,709 (38%)
Asthma this year. 1996" 4,429,374 (30%)
Ever diagnosed
with asthma. 1997= —
Asthma symptoms
this year, 1997s —
U.S. population.' 1996 69.109,000 (26%)
U.S. population,- 1997 69.603,000 (26%)
•MEPS (AHRQ, 2001a,b).
"1996 National Health Interview Survey (NCHS, 1998).
'1997 National Health Interview Survey (NCHS, 1999).
"US Bureau of the Census (2001).
in the United Statns
18 and Over [Row %J_
5.310,538 (62%)
10,165.173(70%)


196.120,000(74%)
198,181,000(74%)

All Ages
8.499.247
14.595.547
25,700.000
11,100.000
265.229,000
267,784,000

    AST:
-------
the total population and is based on responses
to the 1996 NHIS question, "During the past 12
months  did anyone in the family have asth-
ma?" The next two rows illustrate how the for-
mat of the question can  alter the prevalence
estimates. In 1997 the NHIS asked, "Have you
ever been told by a doctor or other health pro-
fessional that you l\ad asthma?" (NCHS, 1999).
Nearly 10 percent of the population responded
affirmatively. Following this they were asked,
"During tlu: past 12 months, have you had an
episode of asthma or an asthma attack?" The
affirmative responses to  this follow-up ques-
tion reflect about 4.1 percent of the population.
The  latter may not capture  those who  are
being actively treated  for asthma but whose
asthma symptoms are fully controlled.

Table 1 also shows  that however it  is defined,
asthma  prevalence is higher in children than
in adults. Children under age 18 represent
about one-quarter of the  U.S. population, but
they make up about 30 percent of  those who
report having asthma, and represent nearly 40
percent of those  who report  medical care
expenditures for asthma. This suggests that
asthma  is more frequent and more severe in
children than in adults.

However  it is specifically defined, asthma
prevalence in the United  States increased dra-
matically  over  the past two decades. The
increase in self-reporled asthma prevalence
from the  mid-1980s  to  the  mid-1990s was
roughly 67  percent (Mannino ct al., 1998;
NCHS, 1998), far outstripping the correspon-
ding 11 percent increase in the U.S. popula-
tion from 1985 to  1996 (U.S. Bureau of the
Census, 2001). Over this period, a number of
changes were taking place in how all medical
services were delivered and paid  for with the
growth  of managed care. At the same  time,
new prescription medications for  asthma and
the development and distribution of new
asthma  diagnosis and treatment guidelines
(NHLBI, 1991) resulted in significiiiit changes
in asthma  treatment  protocols.  Because of
these  changes, we  may see something  other
than proportional changes in asthma-related
medical expenditures since the mid-1980s.

This paper relies primarily  on data from the
1996  Medical Expenditure  Payment  Survey
(MEPS) (AHRQ, 2001a,b) to examine medical
care expenditures for asthma  in the United
States. The MEPS is a very detailed national
survey of households' medical expenditures
in a full year, which allows examination of the
distribution of expenditures and the burden
in terms of how they are paid. The paper also
examines  trends in asthma-related medical
expenditures by comparing the  1996 MEPS
estimates to results based on a similar survey
conducted in 1987 called the National Medical
Expenditure Survey (MMES). Finally, we com-
pare  asthma-related  prescription  medicine
expenditure estimates based on the  MEPS
data to estimates based on an evaluation of
what  expenditures would be if recommended
guidelines were followed (U.S. EPA, 1999).
        *"HN
-------
            Data  Sources  and  Methods
The MF.PS used a national probability sample
designed to collect information  on medical
service use and expenditures among the nonin-
stitutionalized   civilian   U.S.   population
(AHRQ, 2001b).  The- MEPS data include the
responses of the roughly 22,000 survey subjects
regarding their 1996 medical service use and
expenditures, and responses to supplemental
surveys of medical care providers designed to
capture details that the individual subjects may
not know or recall. The MEPS dnta are organ-
ized into the following household component
event files  (AHRQ,  2001a):  prescribed medi-
cines, hospital inpatient stays, emergency room
visits, outpatient visits, and  office-based
provider visits. Each record  in these files con-
tains information on a single  use or purchase of
a medical service (i.e., a physician office visit or
•A prc>s<:ription medication purchase). The infor-
mation includes the total expenditures for the
service event and the amounts paid by each
public and  private payment source.  Personal
characteristics  of tho MEPS survey  res{jon-
dents, including  their unique identifier  num-
ber,  age, and  survey population weight, are
available in the MEPS population characteris-
tics files (AHRQ, 2001b).

Asthma-related records in  the MEPS house-
hold  component event files were identified
using the   International  Classification  of
Diseases, 9'1'  revision. Clinical Modification,
(ICD-9-CM) (U.S. Department of Health and
Human Services, 1998) condition codes in each
record (i.e., asthma 1CD-9-CM = 493). Records
were selected  if any of  the listed condition
codes were for asthma. This approach is con-
sistent with the records selection criteria used
by Smith et al. (1997) in their evaluation of asth-
ma-related medical service use and expendi-
tures using the 1987 NMES data. For compari-
son, we also calculated total asthma-related
expenditures  excluding records that did not
have asthma  as the first-listed diagnosis and
found that these expenditures are 95 percent of
the  expenditures for  all diagnosis listings of
asthma. Thus, any upward bias from using any
listed asthma  diagnosis is minimal.

We used the unique personal identifier for the
subject in each record in the MHI^S data to add
the  age and survey population weights to the
event records. Survey population weights are
provided by the survey authors based on the
probability sampling. The weights are  esti-
mates of how many people in the United
Slates are represented by each survey subject,
and are required to extrapolate from the sur-
vey data to national estimates. For each cate-
gory of medical service, we summed the sur-
vey  population  weight  values across the
selected records to estimate the total national
asthma-related use; in each  medical service
category in 1996.  We calculated correspon-
ding  national  expenditure  and  payment
source estimates by first multiplying the total
expenditure  and  source-specific payment
amounts in a  record by the survey population
weight for the subject. We then summed the
resulting products for total expenditures and
for each payment source across the identified
records for  each medical service category.
This was done separately for those under age
18 and those; age 18 and over.
    ASTHk'A-P.ELATED \
-------
           Asthma-Related Medical Service   Use
           arid  Expenditure Estimates  for  1996
3.1   Total Asthma-
       Related  Medical
       Expenditures
Table 2 provides the MEPS-based national es-
timates of the number of people with asthma-
related medical service expenditures for each
expenditure category by age group for 1996.
Table 2 shows that children are more likely to
have asthma-related medical  expenses than
adults: they accounted for nearly 40 percent of
the people  with  asthma-related  medical
expenses but only about 30 percent of all indi-
viduals  who reported having asthma  (see
Table 1).

Prescription medications are the  most com-
mon asthma-related expense category: about
95 percent of the people who had asthma-
related expenses reported some expenses for
prescription medicines. Fewer than 5 percent
liad expenses for either  hospitnli/.ations or
outpatient facility visits. About 8 percent had
expenses for emergency room visits. Thus, a
small share of asthma patients accounted for
the usage  of hospital and emergency room
services for treatment of asthma.

Children accounted for about 40 percent of
asthma-related medical expenses in all cate-
gories except emergency room visits,  where
             Ihey represented  more than one-half of all
             expenses. The figures in Table 2 suggest that
             about '12 percent of children with any asthma-
             related  medical expenses had  one or  more
             emergency room visits in the past year (1996),
             while this figure was only about 6 percent for
             adults with asthma-related expenses.

             National estimates of the number of asthma-
             relaled medical service occurrences by medical
             service category and by age in 19% are present-
             ed in Table 3. As expected, the more serious
             events were less frequent. Children accounted
             for 55 percent of the emergency room visits for
             asthma, but only about one-third of the hospi-
             tal tuitions and physician visits.

             The national asthma-related medical expendi-
             tures for 1996 calculated from the MEPS are
             also presented in Table 3. In '1996, an estimat-
             ed S5.8 billion was spent on the medical treat-
             ment of asthma,  expenditures for prescrip-
             tions account for  -12 percent of the total, and
             inpatienl hospital and inpalient  physician
             services account for 33 percent of the total.
             Physician office visits account for 18 percent.
             Outpatient facility and emergency room visits
             account for 7 percent. Outpatient facility visits
             are for care received at sites such as respirato-
             ry clinics,  but not in a physician's office.
          Table 2. U.S. Population With Asthma-Related Medical Expenditures in 1996
                            Source: MEPS (AHRQ, 2001a,b).
  Medical Service Category
Under 18 (Row %)
18 and Over (Row %)    All Ages
  Inpatient hospitahzations
  Outpatient facility visits
  Emergency room visits
  Physician office visits
  Prescription medicines
  Any asthma-related medical care
112.894 (39%)
100,400 (34%)
380,163 (56%)
2,034.015 (40%)
2.979.435 (37%)
3,188,709 (38%)
175.646(61%)
196.630 (66%)
296,083 (44%)
3.013.123(60%)
4,971,183(63%)
5,310,538 (62%)
288.540
297.030
676,246
5,047,138
7.950,618
8,499.247
             .- RELATED MEDiCAL ŁXPŁ\P:-i;aES l!i 'H- UNiT = Cl STA'ES-
                                                                     AMD

-------
          Table 3. National Estimates of Asthma-Related Medical Expenditures in 1998
                              Source: MEPS (AHRQ. 2001 a.b).
                               Under 18
    18 and Older
                                                                      All Ages
                          Number  1996 Dollars Number  1996 Dollars  Number 1996 Dollars
Inpalient hospitalizations
Inpatient physician services
Outpatient facility visits
Emergency room visits
Physician office visits
Prescription medications
Total expenses	
134.2

269.2
482.6
5.293.0
$54.3
$40.4
$47.0
$97.6
$317.0
$486.8
$1.243.2
259.6

345.3
400.7
9.720.5
                                                      S1.481.4
                                                      S141.6
                                                      598.3
                                                      S162.3
                                                      $726.3
                                                      51.951.5
                                                      $4,561.6
                     393.7   $1.735.7
                     —      $182.1
                     614.4   S145.4
                     883.3   S259.9
                     15,013.6 $1.043.3
                     —      S2.438.3
                     —      $5.804.7
3.2  Distribution  of
       Asthma-Related
       Medical
       Expenditures
Of  the total  medical expenses for asthma,
roughly 20 percent was spent providing care
and treatment to those under the age of 18.
Tliis is lower than the share of those with asth-
ma expenses who are younger than 18 (see
Table 1), implying lower average individual
expenditures  for children.  For all those
younger  than 18 who received any medical
care for asthma, the average annual expendi-
ture was $384, while the  average  annual
expenditure for those age 18 and older was
S848. Because the frequencies of medical care
events are proportional to, or higher than, the
number of children with asthma expenses,
this implies that expenditures per event are
lower for children than for adults.

Figure 1  shows  that asthma-re la ted expendi-
tures were distributed very unevenly across the
population reporting such expenditures. About
50  percent of asthma-related expenses were
incurred for the treatment of only 5 percent of
the patients: a small share of the patients had
very high annual expenses, and the remainder
had much more modest expenses.

Table 4 shows the annual expenditures  by
medical service category  for the 5 percent of
asthma patients with the highest average total
expenditures across all services and  for the
remaining 95 percent of the asthma patients
who reported any medical expenditures. The
average annual total expenditure per patient
was about 86,500 for the 5 percent of asthma
patients with the highest expenditures, while
average expenditures  for  the  remaining 95
percent of  the asthma patients were about
$350. The 5 percent of patients with the high-
est expenditures account  for 94 percent of
all inpatient  hospitalization  expenditures
(Lnduding inpatient physician  services)  and
42 percent of all expenditures for emergency
room visits. Although the highest 5  percent
spent much more per person on proscription
medicines, 60 percent of the expenditure!) for
the lower 95 percent of patients were for  pre-
scription medicines. For the lower 95  percent
of the asthma patients, expenses for prescrip-
tion  medicines and physician offices visits
combined to account for 87 percent of their
total asthma-related medical expenses.
          Figure 1. Distribution of 1996 Asthma-Related
                    Medical Expenditures
                        cr 0 <•  f> <• O  «•  0 «*
                        f.hara rrf Cvrtwjsft*)) f.*r«RS«
    AS7:
-------
     Table 4. Annual Expenditures for High-Expense Asthma Patients and All Others in 1996
                             Source: MEPS (AHRO, 2001a,b).
                     5% of Patients with Highest Expenses
               Remaining 95% of Patients
                      Total expenditures Patient Annual
 Medical Service Category  {$1S9S Millions)	Average
           Total Expenditures Patient Annual
            ($1996 Millions)      Average
 Inpaiient hospitalizations       $1,652.3         $3,580
 Inpatiem physician services    $159.6          $346
 Outpatient facility visits        $41.2           $89
 Emergency room visits        $109.6          $237
 Physician office visits         $287.8          $624
 Prescription medications       $739.6          $1,602
 All services	$2.990.0         $6.478
                 $83.5
                 $22.5
                 $104.2
                 $150.4
                 $755.5
                 $1.6987
                 S2.814.7
$10
$3
$13
$19
$94
$211
$350
3.3  Sources  of Payment
       for Asthma-Related
       Medical Care
The right side of Table 5 presents the sources
of payment  for  asthma-related medical
expenses, as calculated from the MEPS data.
These results show private insurance account-
ed for 42 percent of the total asthma-related
medical service expenditures. About 23 per-
cent of the total asthma-related expenses were
paid out of pocket by the  patients and their
families. The remaining 32  percent were paid
by public funding sources,  primarily Med-
icare (which primarily covers those over age
65) and Medicaid (which primarily covers low
income households).  There are some  signifi-
cant differences across the medical service cat-
egories as to who paid the expenses. Less titan
'10 percent of the expenses for inpatient hospi-
talization, outpatient  facility, and emergency
room services were paid out of pocket, but 40
percent  of the expenses for  physician office
visits and prescription medicines  were paid
out of pocket. For hospitaii/arion services, the
difference was inude  up by public programs.
However, for outpatient facility and emer-
gency room visits, the difference was made up
primarily by private insurance.

There are some notable differences in sources
of payment for children and adults for asth-
ma-related medical expenses. Out-of-pocket
snares are similar, but private insurance cov-
ered a higher share for children (49 percent),
and  public  programs  (primarily Medicare)
covered a higher share for adults (35 percent).
For those under age 18, public programs (pri-
marily Medicaid) were the primary  payment
source for emergency room visits and outpa-
tient facility visits, accounting for 47 percent
and 73 percent of payments for these services,
respectively. This contrasts with expenses for
physician visits  and prescription medicines
for children for which 24 percent and 21 per-
cent, respectively, were paid by public pro-
grams.  These  findings, combined  with the
high share of asthma-related emergency room
visits accounted for by children  (see Table 2),
suggest that low-income families rely dispro-
portionately on emergency  rooms for treat-
ment of children with asthma.

Table 5 also contrasts  medical  expenditures
and sources of payment for  all conditions to
those for asthma-related medical  care. The
most striking difference  between  medical
expenses for asthma and medical expenses for
all conditions  is  that 42 percent of asthma
expenses were for prescription  medicines,
whereas these made up only  15 percent of the
expenditures for  all conditions. Prescription
medicines are less likely to be covered by pri-
vate insurance or public programs than other
medical rare services, so the higher share; of
        ASTHMA RELATED MESiCAL EXFFND:~IJRES I!J "HE UNrTSD STATES D-STRID'-TiCNS AND TRENDS

-------
Table 5. Payment Sources far All-Condition and Asthma Medical Expenditures for 1996
(Expenses in $1996 Millions)
Source: MEPS (AHRQ, 2001 a.b).




All Conditions Asthma
Medical Service Patient Age Total Private Out of Total Private
Category Group Expense Insurance Pocket Public* Expense Insurance
Inpatienl Under 18 $14,794 64% 2% 31% $254 76%
hospitalization 18 and over $165.905 43% 2% 46% $1.481 33%
facility services All ages 5180,699 44% 2% 45% 51,736 39%
Inpatient Under 18 52,999 74% 4% 20% $40 81%
physician 18 and over $23,506 61% 4% 32% $142 16%
services All ages $26,505 63% 4% 31% $182 31%
Outpatient Under 18 $4,011 77% 7% 14% $47 14%
facility visits 18 and over $50,719 58% 6% 30% $98 81%
All ages $54.730 60% 6% 28% $145 59%
Emergency Under 18 $4,330 56% 11% 12% $98 32%
room visits 18 and over $12,558 49% 11% 34% $162 60%
All ages $16,888 51% 11% 28% $260 50%
Physician Under 18 $12,934 53% 28% 14% $317 44%
office visits 18 and over $92.547 48% 22% 25% $726 39%
All ages $105.481 49% 23% 24% $1.043 41%
Prescription Under 18 $5,541 44% 40% 15% $487 43%
medications 18 and over $65,566 39% 45% 12% $1,952 44%
Adages $71.106 40% 45% 13% $2,438 44%
All services Under 18 $44.608 60% 16% 20% $1,243 49%
18 and over $410,801 46% 14% 33% $4,562 40%
All ages $455.409 48% 14% 31% $5,805 42%
Out of
Pocket
11%
1%
3%
5%
2%
2%
1%
6%
4%
15%
4%
8%
26%
26%
40%
35%
41%
40%
24%
23%
23%

Public*
13%
65%
57%
14%
82%
67%
73%
8%
29%
47%
26%
34%
24%
33%
13%
21%
11%
13%
24%
35%
32%
•Public programs include Medicaid, Medicare, other state, other federal, and workers' compensation.

all asthma expenditures paid out of pocket by
patients and their families (23 percent for asth-
ma versus '14 percent for all conditions) is a
result of the high share of expenditures on pre-
scription medicines for asthma.

3.4 Comparison to
Another Estimate of
Asthma-Related
Medical
Expenditures
Table 6 compares the MEPS-based estimates
of asthma-related medical expenditures for
1996 to estimates reported by Weiss el al.
(2000) for 1994 based on data from 1993
through 1995. The Weiss el al. estimates are
based on annual surveys of medical care uti-


lization in the United States, including the
National Hospital Discharge Survey and the
National Ambulatory Medical Care Survey.
These data sources do not provide the detailed
individual patient expenditure data in the
MEPS that allow for an examination of the dis-
tribution of expenditures across patients, but
they collect limited information on a much
larger share of the more rare; medical care
events such as tiospitalizations and emergency
room visits realized by the U.S. population.
For specific illnesses such as asthma, the
MEPS-bascd national estimates for these more
rare types of events are based on extrapola-
tions from a fairly small sample. Thus, it is
important to compare the findings to those








































AST:-iK<4-RFi.4TŁD WEP:fAl. EXPENDITURE!!  IN THE UN;TED STATES  DISTp:&;j-;ONS AND

-------
       Table 6. Comparison of National Estimates of Asthma-Related Medical Expenditures
 Medical Service Category
 Impatient hospiUjiizalions
 Inpatient physician services
 Outpatient facility visits
 Emergency room visits
 Physician office visits
 Prescription medications
 Total expenses
      1994 Estimates*
 Number       1994 Dollars
JIOpOs)
 477$1,897
 1,708
 1,592
 10,757
$633
$477
$647
$2.452
$6.108
      1996 Estimates"
Number      1996 Dollars
(1000s).
              SI ,736
              S182
              $145
              $260
              $1.043
              $2,438
              $5,805
394

614
883
15,014
 'Weiss at al. (2000). Costs for inpatiant physician services are included in hospitalization costs.
 "MEPS (AHRQ. 2001a.b).
obtained  from other  data sources to assess
their accuracy.

Total annual expenditures for asthma-related
medical care estimated by Weiss et al. for 1994
were $6.1 billion, which is comparable to the
estimate of $5.8 billion based  on the MEPS
data for 1996.' In the two largest expenditure
categories, prescription medications and inpa-
tient  hospitalizations, the estimates are also
quite comparable. There are some differences
between the estimates for outpatient facility
visits and physician office visits, but the total
expend ihires for the two allegories ate com-
parable.  This suggests there may be differ-
                 ences in how these expenditures are catego-
                 rized in the different data sources.

                 One important, difference in ihe two expendi-
                 ture estimates is in their age-based distribution
                 (not shown). Weiss et al.  (2000) report that
                 asthma-related medical expenditures for those
                 under age 18 accounted for roughly 32 percent
                 of the total expenditures. This is roughly pro-
                 portional to the  age  distribution of  asthma
                 prevalence. The equivalent figure in the MEPS-
                 based estimates for asthma patients under age
                 18  is 20 percent of total  expenditures. The
                 MEPS-based result reflects lower expenditures
                 for children per event such as emergency room
                 visit, rather titan fewer events.
! Weiss el al. (2000) also estimated the value of .isthma-reialrd indirect expenses such as the* loss of income associated
with premature mortality, lost work days, and lost school days. Their estimates for 1994 were 53.0 billion for the value
of lost productivity due to asthma-related morbidity and $1 6 billion for the value of lost future earnings due to aslhma-
ivlaleii mortality. A compaiison of results for these categories is not possible with the MEPS data, which do not provide
condition-specific estimates of these outcomes.
        AS~H.ViA-REs.ATSO MEOsCAL frPEND:*ijaŁS l(; ~Hs U\:TSEl
                                                                             S AND

-------
 Irene!
  rends in Astnma ana Astnma-
Reiated Medical Expenditures
4.1 Changes in
Expenditures Since
the 1980s
Table 7 provides two estimates of asthma-
related medical occurrences and expenditures
based on data from the mid-1980s, allowing E ND|TL:RES> IN T^E VH:tr.t> STATES'
                                  AND 'FEHOS

-------
         Table 8. Estimated Asthma Prescription Costs Per Patient Based on Guidelines
                                Source: U.S. EPA (1909).
 Symptom Severity
	Estimate Annual Prescription Cost Per Patient {1998 Dollars)
Share of Asthma
Population	Bronchodiiator     Anti-Inflammatory    Total
Mild-intermittent
Mild-persistenl
Moderate
Severe
Weighted average
35%
35%
25%
5%

$25
S25
$274
$299
$101
$0
$259
$1,139
$2,489
$500
$25
$284
$1,413
$2,789
$601
 Figures are age-weighted averages assuming 10% of all asthma patients are age 6 and younger.
as the totals, but  some  trends  are  clear.
Hospital admissions and emergency room vis-
its stayed the same or declined, so that expen-
diture increases in these categories reflect only
price  increases.  Physician office visits and
expenditures increased, according to both data
sources. Weiss et al.  report an increase  in
expenditures for physician office visits propor-
tional to  the increases in asthma prevalence
and medical prices, but the patient surveys
show a  somewhat less  than  proportional
increase. The greatest increase in expenditures
based on bom types of data sources was for
prescription medicines, which  show  greater
than proportional increases in both  cases.
Overall, it looks like there was a shift in expen-
ditures away  from  hospital and emergency
room services and toward physician office vis-
its and prescription medications. This is consis-
tent with the emphasis in the medical commu-
nity to promote the advances in asthma symp-
tom prevention and control that were made in
the past decade (NHLBI, 1991; 1997).

However, expenditures for hospital and emer-
gency room services are still substantial, and,
although asthma mortality did not increase in
proportion  to  the increase in asthma preva-
lence, it did increase by about 40 percent over
the same period (Mannino et al., 1998). An
obvious  question  is, therefore,  can more
progress  be made in  reducing  rates for the
more serious asthma-related health outcomes?
                         4.2   Prescription
                                Medicine  Usage
                                for  Asthma
                         Although expenditures for prescription med-
                         ications for asthma have clearly increased, it is
                         unclear whether the full benefits of the avail-
                         able preventative medications are being real-
                         ized.tn  this section we compare estimates of
                         what prescription  medication expenditures
                         would  be  per asthma patient if the current
                         guidelines were followed to the actual expen-
                         ditures per patient as reported in the MEPS.

                         Estimates provided by a  U.S. EPA-sponsored
                         asthma cost-of-ilmess study (U.S. EPA, 1999)
                         provide an interesting contrast to the prescrip-
                         tion medication expenditure estimates  from
                         the MEPS. For the EPA  study, current treat-
                         ment guidelines (NHLBI, 1997) were used to
                         estimate what annual prescription medication
                         expenditures  would be  for  asthma  patients
                         with varying levels of asthma severity if asth-
                         ma medication guidelines were followed. This
                         evaluation was done separately for those age 6
                         and under 
-------
         Table 9. Annual Asthma Prescription Expenditures Per Patient Based on MEPS
                              Source: MEPS (AHRQ, 2001 a.b).
 Share of Asthma Population
  Annua! Asthma Prescription Expenditure Per Patient in 1996
Bronchodilator   Anti-Inflammatory     Other	Total
 35%
 35%
 25%
 5%
 Weighted average
$11
$46
$236
$877
$123
$3
$25
$171
$774
$91
$6
$28
$88
$539
$60
$21
$102
$506
$2,199
$280
 Shares are percentiles ot the national population with asthma medical expenditures (8.5 million people),
 including those with no asthma-related prescription medicine expenditures, sorted by size of the pre-
 scription medicine expenditure.
The  EPA  study estimates arc based on the
usage of five types of medicines, which are
either brcmchodilalors (short-acting and long-
acting albuterol) or anti-inflammatories  (cro-
molyn,  beclomethasone  dipropioiiate,  or
methyl  prednisolone). The  much higher
expected annual costs for those with moderate
or severe asthma is the result of the treatment
guidelines  recommended  us;)go  of   anti-
inflammatory medications several limes a day
as a preventative treatment.

Table 8  shows that the expected average
annual (1998) prescription medication cost for
an asthma patient is about S600, but the MEPS
datd show that for .ill individuals with any
medical expenditures for asthma in 1996, the
average annual expenditure for asthma-relat-
ed prescription medicines was less than $300.
Because of this difference between estimates
of expected average asthma prescription costs
based on the treatment guidelines and the
reported expenditures in the MEPS, we exam-
ined the MEPS data on asthma-related pre-
scription  medicine expenditures  in  more
detail  to  see  if the  differences  could  be
accounted for.

Table 9 shows the average asthma-related pre-
scription  medicine  expenditures from the
MEPS data for percenliles of  the population
with any  asthma-related  medical  expendi-
tures. These percentiies are selected to match
the allocation of asthma severity used for the
                 EPA estimates in Table 8. Prescription medi-
                 cine names are included for each purchase in
                 the MEPS data. We grouped these into three
                 categories: bronchodilator, anti-inflammatory,
                 and other, based on the JAMA (2001) list of
                 asthma drugs. We were unable to distinguish
                 between  short-acting and  long-acting bron-
                 chodilators because the names are the same.
                 Medicines in I he "other" category are  those
                 that are not listed as asthma drugs by JAMA.
                 Some of  these may be other names for  the
                 same types  of asthma  medicines, but  some
                 were other types of medicines such as antibi-
                 otics and antihistamines that were recorded in
                 the MEPS data with a diagnosis of asthma.
                 Even if all of the medicines in the "other" cat-
                 egory were anti-inflammatory medicines,  the
                 ratio of expenditures for anti-inflammatories
                 to expenditures for bronchodilators is no more
                 than 1.5 to 1. The EPA estimates suggest that
                 for all asthma patients except those with rnild-
                 intermittent asthma, the ratio of anti-inflam-
                 matories  to bronchodilators should be at least
                 4 to 1. For the 5 percent of the asthma patients
                 with the highest expenditures, the MEPS data
                 show average prescription medicine expendi-
                 tures  are about 80 percent of what  the EPA
                 study estimates for the top  5  percent of all
                 asthma patients, but the EPA estimates sug-
                 gest that  about 10 percent would be for bron-
                 chodilators. The MEPS data show that at least
                 40 percent of the medicine expenditures for
                 this group are for bronchodilators.
                   K«EPiPAi. EXPENDI't'RES. 'N TSE LINKED STATE? iJISTPiB'J'iCNS ANO

-------
            Conclusions
The MEPS-b.«;ed estimate of total annual med-
ical care expenditures for asthma  for 1996 is
about $5.8 billion. The largest category of
expenditures is prescription medications and
the second largest is inpatierit hospitalizations.
These results are consistent with estimates by
Weiss et ai. (2000) for the mid-1990s based on
different data sources.

The comparison of the mid-1990s estimates to
the previously published mid-1980s estimates
shows some significant trends in asthma-relat-
ed medical care usage. There were declines, or
at most very small increases, in the frequencies
of the most seven: of the direct medical out-
comes (i.e., hospitalizalions and  emergency
room visits) relative to the 67 percent growth in
asthma prevalence from the mid-1980s to 1996
(Mannino  et al., 1998; NCHS, 1998). At  the
same time,  there were proportional or greater
increases in physician office visits and pre-
scription medicine expenditures. Both trends
•in; consistent  with the  goals of the asthma
treatment and  diagnosis guidelines that were
first  released  in 1991 (NHLBL 1991). These
guidelines emphasize the use of prescription
medications and physician office visits, as well
as reducing exposures to asthma triggers, to
help increase control over asthma  symptoms.
As noted by Weiss et al. (2000), hospital facility
usage declined for all illnesses because of the
increased emphasis under managed care on
controlling the use of high cost medical servic-
es, and the decline overall was greater than the
decline  for asthma-related hospitalization
when the increase in asthma prevalence is
accounted for. Weiss et al. (2000) further note
that between 1985 and 199'! there was a rough-
ly 11 percent decline in the average length of
stay for an asthma-related hospitalization.

An  important remaining question then is
whether  increases in prescription  medicine
usage and physician office visits reflect reason-
ably comprehensive adoption of recommend-
ed guidelines for asthma  treatment (NHLBI,
1991; 1997). The  U.S. EPA (1999) estimated
what average annual expenditures of prescrip-
tion medications for asthma would be if cur-
rent treatment guidelines were followed. These
estimates reflect assumptions about the distri-
bution  of asthma severity in the population
with asthma and estimates of the prescription
medication treatment protocol consistent with
the  most  recent treatment guidelines  for
patients with varying levels of asthma severity
(U.S. EPA, 1999; NHLBI, 1997). In contrast to
these estimates, the MEPS data show that asth-
ma patients are not, on .average, using asthma
medicines,  especially anti-inflammatory med-
ications, at the rate that the guidelines appear
to recommend. The average .inriual prescrip-
tion  medication expenditure per  asthma
patient is about one-half of  what the guidelines
would  recommend,  given  the assumptions
used for  the FPA estimates. Also, the relative
expenditure shares for bronchodilalors versus
anti-tnflammatories suggest that the former are
being used more and the  latter less than the
guidelines recommend.
   •\l    *3~HMA RELATED MEB:CAL EVPENDi'UftES l!i "He UN:TED STAGES DiS~PI3:,-~ION3 AND TR

-------
It appears thai there is room for improvement
in terms of adoption of the treatment guide-
lines, especially regarding  the use  of  anti-
inflammatory medications to prevent or reduce
asthma symptoms. Increased compliance with
these guidelines might continue the  trend of
reducing rates  of  hospitaliziition and emer-
gency  room  visits  for  asthma  patients.
However, the data presented here also suggest
that compliance with these guidelines may face
some barriers. One potential barrier is likely to
be the high share  of prescription medication
expenses that must be paid out of pocket by
patients and their families. These our-of-pocket
payment  levels are especially noteworthy
given that they suggest asthma places a rela-
tively high economic burden on the patient rel-
ative to other medical conditions:  the average
share of oul-of-pockel payments for all ration-
al health expenditures was 14 percent while the
out-of-pocket share for  asthma-related expen-
ditures was 23 percent, according to the MEPS
data for 1996. Further substitution of prescrip-
tion medications and physician office visits for
hospital and emergency room services would
push the oul-of-pockel share even higher, caus-
ing an even greater financial burden for asthma
patients' families.
                                                   ŁTAT=3  DISTRIBUTIONS

-------
Refer
ere rices
AHRQ: Agency for Healthcare Research and Quality. Household component event files. Accessed
2/2001 at http://www.mep's.ahrq.%ov/Data Pub/HC EventData96.htm (2001a).

AHRQ: Agency for Healthcare Research and Quality. Household component point-in-time files.
Accessed 2/2001 at htrp://www.meps.ahrq.gov/Data Pub/HC PiTData.htm#hcOUl (2001b).

JAMA: Journal of the; American Medical Association. Treatment center: asthma medications.
Accessed 4/2001 at http://www.ama-assn.org/special/asmma/treatnmt/drug/dmgtop-htm (2001).

Mannino DM, Homa DM, Perbiwski CA, Ashizawa A, Nixon LI.., Johnsoti CA, Ball I..B, Jack E,
Kang DS. 1998. Surveillance for asthma: United Stales, '1960-1995. In: CDC Surveillance
Summaries, April 24,1998. MMWR Morb Mortal Wkly Rep 47:1-28.

NCHS: National Center for Health Statistics. 1998.1996 National Health Interview Survey:
CD-ROM Series 10, No. 11A. Hyattsville, MD: National Center for Health Statistics; November.

NCHS: National Center for Health Statistics. 1999. 1997 NHIS Survey Description. Accessed
12/9/1999 at ftp://ftp.cdc.gov/pub/Health Statistics/NCHS/Dataset  Documentation/
NH1S/1997A

NHLBI: National Heart, Lung, and Blood Institute. 1991. Expert panel report: guidelines for the
diagnosis and management of asthma. Bethesda, MD: LT.S. Department of Health and Human
Services. NTH Publication No. 91-3042.

NHLBI: National Heart, Lung, and Blood Institute. 1997.  Expert panel report 2: guidelines for the
diagnosis and management of asthma. Bethusdd, MD: U.S. Department of Health and Human
Services. NIH Publication No. 97-1051.

Smith DH, Malone DC, Lawson KA, Okamoto LG, Battista C, Saunders WB. 1997. A national
estimate of the economic cosLs of asthma. Am J Reap Cril Care Med 156:787-793.

US. Bureau of the Census. 2001. Statistical abstract of the United States: 2001 (121" edition)
WashingtOiX DC: US. Government Printing Office.

US DHHS: IIS. Department of Health and Human Services. 1998. The International Clasfifcatitm of
Diseases, 9tli Revision, Clinical Modification: ICD-9-CM, 6th ed. Public Health Service, Health Care
Financing Administration. U.S. Government Printing Office, Washington, DC.

US EPA: U.S. Environmental Protection Agency. 1999. Cost of illness handbook. Washington, DC:
U.S. Environmental Protection Agency. Accessed at http://www.epa.gov/oppt/coi.

Weiss KB, Sullivan 3D, Lyttle CS. 2000. Trends in the cost of illness for asthma in the United
States, 1985-1994. / Allergy Clin Immunol 106:493-499.
                       MEDICAL E*PE\Dri;3=Ł IJJ "HE UNITED ST'.'FV DiS~PI3i;TiGN5 AND TRENDS

-------