Gender Differences in Management and
Outcomes of AMI Patients in Taiwan, 1997-2007:
The role of health information
PRESENTER: NICOLE HUANG
NATIONAL YANG MING UNIVERSITY
Background
 Extensive researches have examined gender differences in use of
cardiac procedures and outcomes for AMI.
 Use of interventional cardiac procedure

In general, most studies found that women were less likely to use cardiac procedures
(catheterization/revascularization) than men.

However, some found no significant difference in utilization of cardiac procedures.

Most findings are limited to western societies.
 Survival Outcomes

Many studies report that women experience poorer survival outcomes than men,
whereas others indicate no difference. Under particular settings, women may fare
better than men.

Strong age-gender mortality interaction for AMI.
Background
 Proposed Mechanisms

Gender difference may not necessarily reveal itself as obvious sex
discrimination.

Sex differences in

disease conceptualization

risk perception of medical intervention

symptom presentation: misconception or ignorance

Communication patterns between physicians and patients

Hence, many believe that the status of the patient can be strengthened
through improved consumer information

But it is unclear whether and to what extent information can effectively
narrow gender disparities in health care.
Research Objectives
 While health professionals are presumably to be medically
knowledgeable, be able to talk in the same language, and have
better access to the system:

To assess potential gender disparities in use of invasive cardiac procedures
and survival outcomes exist between men and women in Taiwan, a typical
Asian population

To determine if gender disparities also exist among health professionals

If there are differences, are they smaller than those among general nonhealth professional patients?
Methods

Setting


Taiwan National Health Insurance (NHI)

Universal coverage with enrollment rate of 99%

Comprehensive package: WM, TCM, DM, and prescription drugs

Wage-based premium & per-capita premium

The incidence of new AMI (2007): 70 /100,000 population aged 30-85
Data

NHI inpatient claims, enrollment files, major disease/injury files

The medical personnel registry

The hospital registry
Methods


Sample

A total of 95,197 eligible AMI patients aged 30 to 85 years, who had been
admitted to a hospital for a new AMI episode (ICD_9_CM 410) in Taiwan
between 1997 and 2007, were identified.

In order to make health professionals (including their relatives) and nonhealth professional patients more comparable, we excluded those patients
with monthly wage＜ 40,000 New Taiwan (NT) dollars
Dependent Variables

Use of Catheterization/ Revascularization within 1 year of index
admission

30-day and 1-year mortality
Methods

Statistical Analyses

Generalized Estimating Equations (GEE): the relatives odds for the use of a
catheterization and revascularization procedure within 1 year of the index
admission.

Cox proportional hazards models: differences in survival between men and
women

Adjusting for patient characteristics (age, co-morbidity, urbanization) &
provider characteristics (age, gender, specialty, case volume, level of practice)

Stratification analysis by age

Sensitivity analyses
Table 1: Characteristics of new AMI admissions in Taiwan, by gender and health professional status, 1997-2007
Health professionals and Relatives
General
Characteristics
Male
Female
Male
Female
p-value
n=639
n=140
n=7800
n=2098
%
%
%
%
Patient Characteristics
Age (years)
63.1
68.1
59.2
71.4
<0.001
Charlson co-morbidity
<0.001
0
352
50
4549
738
55.1
35.7
58.3
35.2
1
212
57
2317
808
33.2
40.7
29.7
38.5
≧2
75
33
934
552
11.7
23.6
12.0
26.3
Urbanization
0.703
Urban
483
106
5635
1520
75.6
75.7
72.2
72.4
Suburban
118
28
1888
493
18.5
20.0
24.2
23.5
Rural
38
6
277
85
5.9
4.3
3.6
4.1
Year
0.264
1997
36
7
399
112
5.6
5.0
5.1
5.3
1998
41
12
426
137
6.4
8.6
5.5
6.5
1999
50
12
525
148
7.8
8.6
6.7
7.1
2000
78
14
622
169
12.2
10.0
8.0
8.1
2001
64
16
730
238
10.0
11.4
9.4
11.3
2002
58
17
803
239
9.1
12.1
10.3
11.4
2003
74
11
837
252
11.6
7.9
10.7
12.0
2004
77
14
920
299
12.1
10.0
11.8
14.3
2005
65
24
1023
340
10.2
17.1
13.1
16.2
2006
54
8
812
128
8.5
5.7
10.4
6.1
2007
42
5
703
36
6.6
3.6
9.0
1.7
Outcomes
374
59
4825
878
Catheterization
58.5
42.1 <0.001
61.9
41.8
Revascularization
335
45
4222
678
52.4
32.1 <0.001
54.1
32.3
30-day mortality
74
25
809
436
11.6
17.9 0.043
10.4
20.8
1 year mortality
110
40
1276
755
17.2
28.6 0.002
16.4
36.0
p-value
<0.001
<0.001
0.476
<0.001
<0.001
<0.001
<0.001
<0.001
Table 2: Adjusted odds (95% CI) of men undergoing catheterization or any revascularization procedure compared to
women, by health professional status and age
≧65
Total
<65
GEE
OR
95%CI
OR
95%CI
OR
95%CI
Catheterization
Non-HP Male
1.43
1.26-1.61*
1.78
1.41-2.25*
1.31
1.14-1.51*
HP Male
1.80
1.14-2.83*
1.39
0.64-3.02
1.96
1.07-3.59*
Non-HP Male
1.61
1.42-1.82*
2.16
1.72-2.71*
1.44
1.24-1.66*
HP Male
2.21
1.40-3.50*
2.36
1.14-4.87*
2.09
1.11-3.95*
Revascularization
The model was adjusted for patient characteristics (age, co-morbidity, urbanization), provider
characteristics (age, gender, specialty, case volume, and level of practice), and year.
Table 3: Adjusted hazard ratios (95% CI) of men for 30-day and 1-year mortality compared to women, by health
professional status and age
≧65
Total
<65
Cox proportional hazard model
HR
95%CI
HR
95%CI
HR
95%CI
30-day mortality
Non-HP Male
HP Male
0.91
0.81-1.03
0.59
0.44-1.80*
0.98
0.86-1.12
0.91
0.56-1.46
0.41
0.13-1.29
1.11
0.65-1.88
0.86
0.78-0.94*
0.55
0.44-0.70*
0.92
0.83-1.02
0.87
0.59-1.27
0.40
0.16-1.01
1.04
0.68-1.60
1 year mortality
Non-HP Male
HP Male
The model was adjusted for patient characteristics (age, co-morbidity, urbanization), provider
characteristics (age, gender, specialty, case volume, and level of practice), and year.
Summary

Main findings:


Use of cardiac procedures:

Significant gender disparities in management were observed in
Taiwan and persisted after stratifying by age

Similar gender disparities also existed among health professionals
Survival outcomes

In younger cohort, men fared significantly better in survival
outcomes than women

In older cohort, such difference diminished. For health
professionals, female were even had lower mortality hazards than
men
Summary
 Study limitations

Small number of female health professional patients may not allow for more
detailed analyses

Data limitations: Lack of clinical information (e.g.

Generalizability
 The preliminary findings suggest that

Medical knowledge alone may not explain observed gender differences in
access to invasive cardiac procedures and outcomes

Apparent disadvantages in survival outcomes among younger women (aged
below 65) deserve more attentions.
Thank You For Your Attention
Characteristics
Physician characteristics
Age
<35
35-39
40-44
45-49
≧50
Gender
Female
Male
Specialty
Non-Cardiology
Cardiology
Case volume
<150
≧150
Hospital level
Medical center
Regional
District
Table 1: Characteristics of new AMI admissions in Taiwan, by gender and health professional status, 1997-2007
Health professionals and Relatives
General
Male
Female
Male
Female
Characteristics
p-value
p-value
n=639
n=140
n=7800
n=2098
%
%
%
%
Patient Characteristics
Age (years)Health professionals
63.1 and Relatives
68.1
59.2
71.4General<0.001
<0.001
Charlson co-morbidity
<0.001
Male
Female50 35.7 p-value
Male738 35.2 <0.001
Female
0
352
4549
55.1
58.3
1
57
2317n=7800
808
33.2
29.7
n=639
% 212n=140
% 40.7
% 38.5n=2098
%
≧2
75
33
934
552
11.7
23.6
12.0
26.3
Urbanization
0.703
0.476
Urban
483
106
5635
1520
75.6
75.7
72.2
72.4
Suburban
118
28
1888
493
18.5
20.0 0.532
24.2
23.5
Rural
38
6
277
85
5.9
4.3
3.6
96
28
1349
15.0
20.0
17.34.1 342
16.3
Physician characteristics
Age
0.532
0.007
195
42
2402
617
30.5
30.0
30.8
29.4
<35
96
28
1349
342
15.0
20.0
17.3
16.3
164
33 4223.630.0
1968
498
25.7195 30.5
23.7
35-39
2402
617 25.2
30.8
29.4
40-44
164
33
1968
498
25.7
23.6
25.2
23.7
98
23 2316.416.4
1248
379
15.398 15.3
18.1
45-49
1248
379 16.0
16.0
18.1
50
≧
833
10.7
86
14 1410.010.0
833 262 10.712.5 262
13.586 13.5
12.5
Gender
0.480
0.281
16
5
194
61
Female
2.5
3.6 0.480
2.5
2.9
623
135
7606
2037
Male
97.5
96.4
97.5
97.1
16
5
194
61
2.5
3.6
2.5 <0.001
2.9
Specialty
0.094
254
45
2909
982
Non-Cardiology
39.7
32.1
37.3
46.8
623
135 9596.467.9
7606
2037
97.5385 60.3
97.1
4891
1116 97.5
Cardiology
62.7
53.2
Case volume
0.424
<0.001
0.094
<150
264
63
3251
1006
41.3
45.0
41.7
48.0
254
45 7732.155.0
2909
982
≧150
4549
1092 37.3
58.3
52.0
39.7375 58.7
46.8
Hospital level
0.481
<0.001
95 7467.952.9
4891
60.3361 56.5
53.2
Medical center 385
4221
1023 62.7
54.1
48.8 1116
Regional
232
52
2879
745
36.3
37.1
36.9
35.5
0.424
District
46
14
700
330
7.2
10.0
9.0
15.7
Year
0.264
264
63
3251
1006
41.3
45.0
41.7 <0.001
48.0
1997
36
7
399
112
5.6
5.0
5.1
5.3
375
77 1255.0 8.6
4549
1998
426
137 58.36.5 1092
6.4
5.5
58.741
52.0
1999
50
12
525
148
7.8
8.6
6.7
7.1
2000
78
14
622
169
12.2
10.0 0.481
8.0
8.1
64
16
730
238
2001
10.0
11.4
9.4
11.3
361
74 1752.9
4221 239 54.1
1023
56.558
48.8
2002
803
9.1
12.1
10.3
11.4
2003
837
252 36.9
10.7
12.0
232
52 1137.1 7.9
2879
745
36.374 11.6
35.5
2004
77
14
920
299
12.1
10.0
11.8
14.3
46
14 2410.017.1
700 340 9.016.2 330
7.265 10.2
15.7
2005
1023
13.1
2006
54
8
812
128
8.5
5.7
10.4
6.1
2007
42
5
703
36
6.6
3.6
9.0
1.7
Outcomes
374
59
4825
878
Catheterization
58.5
42.1 <0.001
61.9
41.8 <0.001
Revascularization
335
45
4222
678
52.4
32.1 0.000
54.1
32.3 0.000
30-day mortality
74
25
809
436
11.6
17.9 0.000
10.4
20.8 0.000
1 year mortality
110
40
1276
755
17.2
28.6 <0.001
16.4
36.0 <0.001
p-value
0.007
0.281
<0.001
<0.001
<0.001