Identifying Racial and Ethnic Disparities in
Admissions for Ambulatory Care Sensitive
Conditions among Medicare Beneficiaries
Presented by
Arthur J. Bonito, Ph.D.1; Celia R. Eicheldinger, M.S.1;
Arthur A. Meltzer, Ph.D.2, And Linda G. Greenberg, Ph.D.3
1RTI International; 2CMS; 3 AHRQ
Presented at
The 2005 Annual Research Meeting of AcademyHealth,
Boston, MA, June 28, 2005
3040 Cornwallis Road
Phone 919-541-6377
■
P.O. Box 12194 ■ Research Triangle Park, NC 27709
Fax 919-990-8454
e-mail ajb@rti.org
RTI International is a trade name of
Research Triangle Institute
Background
2

Limited information and few previously published
studies exist on access to care for minority Medicare
beneficiaries, other than African Americans, using
Medicare administrative claims data.

CMS sponsored this project to improve identification of
Asians and Hispanics, as well as to examine disparities
in health care access and use under Medicare.

Avoidable hospitalizations for ACSCs provide one
indication of limited access and receipt of less-thanadequate primary care.
Ambulatory Care Sensitive Conditions

3
Hospital or Emergency Room (ER) admissions for 15
Ambulatory Care Sensitive Conditions (ACSCs) that
include the following :

Chronic (5) – chronic lung disease (asthma and
COPD), congestive heart failure, seizures,
diabetes, and hypertension

Acute (8) – cellulitis; bacterial pneumonia; urinary
tract infection; ulcers; hypoglycemia; hypokalemia;
dehydration; ear, nose, and throat infections

Preventable (2) – influenza and malnutrition
Study Goals
4

To improve accuracy of racial/ethnic identification of
Medicare beneficiaries to include: non-Hispanic
White, Black, Hispanic, Asian/Pacific Islander (A/PI),
and American Indian/Alaska Native (AI/AN).

To identify racial/ethnic disparities in hospital or
emergency room admissions for ACSCs.
Methods and Data

Developed algorithm to more correctly identify Medicare
beneficiaries’ race/ethnicity:
 Used Spanish and Asian surname lists from US Census.
 From Medicare enrollment database (EDB), used first and
last name, race/ethnicity, language preference and place
of residence.
 Used common first names from web sources.

Used Medicare Part A claims for 2002 to estimate hospital
and ER admissions for ACSCs.

Selected a stratified random sample of 1.96 million FFS
Medicare beneficiaries (over-sampling minorities).
5
Data Limitations
6

CMS obtains race/ethnicity data on Medicare
beneficiaries from SSA, which categorizes “Hispanic”
as a race code.

We present findings for AI/ANs despite underidentification on the EDB.

CMS has been working with IHS since 1999 to
improve identification of AI/AN beneficiaries.

Analyses show small predictable bias.
2002 Medicare FFS Study Sample
7
Race/Ethnicity
Sample
Medicare FFS

NH White
329,954
26,779,400

Black
328,246
3,053,618

Hispanic
534,196
720,664

A/PI
415,190
449,914

AI/AN
120,557
121,818

Other/Unknown
231,978
471,630

TOTAL
1,960,121
31,579,044
Analysis Approach
8

We examined hospital or ER admissions for each type of
ACSC - chronic, acute, preventable, and any.

We examined percentages with hospital or ER admission
by type of ACSC, race/ethnicity, sex, and age group.

The following tables include stacked bar graphs for each
type of ACSC by race, sex, and age.
Figure 1
Percentage of male Medicare beneficiaries with admissions for chronic
Percentage of male Medicare beneficiaries with a chronic ambulatory care sensitive condition
ambulatory
care sensitive
conditions by age group and race/ethnicity: CY 2002
by age group and race/ethnicity: calendar year 2002
5.95
5.53
5.60
85+
4.63
4.85
5.07
75-84
65-74
< 65
3.54
4.99
4.12
3.43
4.53
3.05
2.46
2.50
1.44
6.78
4.50
White
5.83
4.48
Black
Hispanic
Race/Ethnicity
9
3.70
A/PI
AI/AN
Figure 2
Percentage of female Medicare beneficiaries with admissions for chronic
Percentage
of female
Medicare beneficiaries
with
admissions
for
chronic ambulatory CY
care 2002
ambulatory care
sensitive
conditions
by
age
group
and
race/ethnicity:
sensitive conditions by age group and race/ethnicity; calendar year 2002
6.70
6.00
6.62
85+
5.00
75-84
5.49
4.83
< 65
5.52
5.06
3.50
2.94
3.72
2.54
Black
Hispanic
Race/Ethnicity
10
2.22
7.22
5.44
5.09
4.79
1.41
8.19
White
65-74
4.04
A/PI
AI/AN
Preliminary Results for Chronic ACSCs
11

Across all race/ethnicity groups, women have higher
percent of admissions for chronic ACSCs than men.

Typically, men and women under age 65 have higher
percent of admissions for chronic ACSCs.

Among elderly men and women (65 years of age and
over), admissions for chronic ACSCs increase with
age.

A/PI and White beneficiaries have lowest percent of
admissions for chronic ACSCs, Blacks and AI/ANs
have the highest percent, Hispanics falls in between.
Figure 3
Percentage of male Medicare beneficiaries with admissions for acute
of male Medicare
beneficiaries
with group
admissions
for ambulatory
care sensitive
ambulatoryPercentage
care sensitive
condition
by age
and
race/ethnicity:
CY 2002
condition by age group and race/ethnicity: calendar year 2002
9.98
85+
75-84
65-74
< 65
7.07
5.98
5.69
5.42
4.46
4.38
3.82
3.68
4.01
3.14
2.24
2.43
2.51
1.38
4.25
5.02
White
Black
3.20
Hispanic
A/PI
Race/Ethnicty
12
5.22
4.04
AI/AN
Figure 4
Percentage of female Medicare beneficiaries with admissions for acute
Perrcentage
of female
Medicare beneficiaries
admissions
for acute ambulatory care
ambulatory care
sensitive
condition
by age with
group
and race/ethnicity:
CY 2002
sensitive condition by age group and race/ethnicity: calendar year 2002
9.38
7.42
6.50
5.61
6.44
5.19
4.73
4.06
4.23
3.91
2.71
3.31
2.34
1.52
5.82
White
7.17
5.27
Black
Hispanic
Race/Ethnicity
13
5.00
7.93
3.93
A/PI
AI/AN
85+
75-84
65-74
< 65
Preliminary Results for Acute ACSCs
14

Across all race/ethnicity groups, women have higher
percent of admissions for acute ACSCs than men.

Men and women age 85 and over have highest
percent of admissions for acute ACSCs.

Among elderly men and women, admissions for acute
ACSCs increase with age.

A/PI beneficiaries have lowest percent of admissions,
Blacks and AI/ANs have the highest, and Whites and
Hispanics fall in between.
Figure 5
Percentage of male Medicare beneficiaries with admissions for preventable
Percentage
of male Medicare
beneficiaries
with
admissions
for preventive
ambulatory care
ambulatory
caresensitive
sensitive
condition
by
age
group
and
race/ethnicity:
CY 2002
condition by age group and race/ethnicity: calendar year 2002
0.10
0.15
0.11
0.08
0.09
0.08
0.04
0.04
0.09
White
0.04
0.04
0.04
0.05
0.03
0.03
0.10
Black
0.05
0.04
Hispanic
A/PI
Race/Ethnicity
15
0.12
0.01
AI/AN
85+
75-84
65-74
< 65
Figure 6
Percentage of female Medicare beneficiaries with admissions for preventable
Percentage of female Medicare beneficiaries with admissions for preventive ambulatory care
ambulatory
caresensitive
sensitive
conditions
byand
age
group and
race/ethnicity:
CY 2002
conditions
by age group
race/ethnicity:
calendar
year 2002
0.14
0.11
85+
0.09
75-84
0.13
0.10
0.06
0.04
0.07
0.03
0.10
0.08
0.21
0.06
0.03
0.03
0.06
0.10
0.15
0.10
0.06
White
Black
Hispanic
Race/Ethnicity
16
A/PI
AI/AN
65-74
< 65
Preliminary Results for Preventable ACSCs
17

Across all race/ethnicity groups, women have a higher
percent of admissions for preventable ACSCs than
men.

Typically, among men and women – ages 85 and over
and under 65 – have the highest percent of admissions
for preventable ACSCs.

Typically, among elderly men and women, admissions
for preventable ACSCs increase with age.

A/PI beneficiaries have lowest percent of admissions,
Blacks and AI/ANs have the highest, and Whites and
Hispanics fall in between.
Figure 7
Percentage of male Medicare beneficiaries with admissions for any
Percentage of male Medicare beneficiaries with admissions for any ambulatory care sensitive
ambulatory care sensitive
condition
group calendar
and race/ethnicity:
CY 2002
condition
by age groupby
and age
race/ethnicity:
year 2002
13.00
10.84
14.42
9.87
10.14
9.90
8.10
7.23
7.67
8.16
7.89
5.17
5.30
4.56
2.96
11.05
7.76
White
Black
6.41
Hispanic
A/PI
Race/Ethnicity
18
9.79
7.59
AI/AN
85+
75-84
65-74
< 65
Figure 8
Percentage of female Medicare beneficiaries with admissions for any
Percentage of female Medicare beneficiaries with admissions for any ambulatory care
ambulatory care sensitive
condition
age
and calendar
race/ethnicity:
CY 2002
sensitive condition
by ageby
group
andgroup
race/ethnicity:
year 2002
14.02
14.63
85+
11.59
75-84
10.36
11.38
11.09
< 65
9.23
7.37
7.49
9.21
6.57
4.93
9.10
4.78
3.02
14.20
19
13.49
9.66
9.56
White
65-74
Black
Hispanic
7.40
A/PI
AI/AN
Preliminary Results for any ACSCs

Across all race/ethnicity groups, women have higher
percent of admissions for all ACSCs combined than men.

Men and women ages 85 and over have highest percent of
admissions for all ACSCs combined.

Among elderly men and women, admissions for all ACSCs
combined increase with age.

A/PI beneficiaries have lowest percent of admissions,
Blacks and AI/ANs have the highest, and Whites and
Hispanics fall in between.
20
Summary of Preliminary Results

21
There is considerable consistency across the 15 individual
ACSCs and the four grouped -- chronic, acute, preventable
and any -- with respect to racial/ethnic differences in the level
of hospital or ER admissions, with age and sex controlled.

Black and AI/AN beneficiaries have the highest levels of
ACSC hospital or ER admissions.

A/PI beneficiaries have the lowest level of ACSC hospital or
ER admissions.

Hispanic and White beneficiaries typically occupy the
middle ground, with lower levels of ACSC hospital or ER
admissions than Black and AI/AN, but higher than A/PI.
Conclusions

The improved race/ethnicity variable indicates sizeable and
consistent differences in admissions for ACSCs, suggesting
differences in access by some minority groups to timely and
appropriate primary care services.

More accurate coding for Hispanics and A/PIs allows a
unique opportunity to increase our knowledge of disparities
in health care use and outcomes.

Additional research is needed, including multivariate
analysis to adjust for differences in SES, health status,
disease levels, as well as hospital, ER, outpatient, and
ambulatory care service use.
22