Transcript Abdominal Aortic Aneurysm in Portuguese Mainland State

Introdução à Medicina II
Ana Catarina Rodrigues, Carolina Rodrigues, Catarina Cruz, Diogo Costa, Isabel Vazquez, Joana Garcia,
Joana Rei, João Paulo Carvalho, José João Monteiro, José Pedro Vale, Lúcia Vieira, Manuel Neiva de
Sousa, Marisa Martins and Ricardo Coutinho
Class 2
Advisor: Alberto Freitas
1.
Introduction
1.
2.
3.
2.
Background
Justification
Aims
Participants and Methods
1.
2.
3.
4.
5.
Study participants
Study design
Data collection methods
Variable descriptions
Statistical analysis
3.
Results
4.
Conclusion and Discussion
5.
References
1.
Introduction
1.
2.
3.
2.
Background
Justification
Aims
Participants and Methods
1.
2.
3.
4.
5.
Study participants
Study design
Data collection methods
Variable descriptions
Statistical analysis
3.
Results
4.
Conclusion and Discussion
5.
References

Abdominal Aortic Aneurysm (AAA)
›
Permanent focal dilatation of the abdominal artery below the
kidneys (infrarenal) to at least1,5 times its normal diameter1
›
Normal values (above 50 years-old)2
 Men: 1,99 cm
 Women: 1,66 cm
 Convention: an infrarenal aorta of 3
cm in diameter or larger is considered
aneurysmal3
Normal aorta
Aorta with large
abdominal aneurysm
1
Upchurch (2006) Am Fam Physician, 73(7): 1198-204
2
Lederle (1997) J Vasc Surg, 26(4): 595-601
3 Johnston
(1991) J Vasc Surg, 13(3): 452-8

Abdominal aortic aneurysm affects 1% of individuals over the
age of 55 and increases in incidence by 2% to 4% per
decade thereafter1

Main risk factors:
›
Gender:
 Men are 3 times more likely to develop this type of aneurysm than
women2
 Men are 10 times more likely to have an aneurysm of this type of 4
cm or larger3
›
Age
 Incidence rapidly increases after age 55 in men / 70 in women4
1
2
Berman (2008) J Vasc Surg, 47(2): 287-295
Egorova (2008) J Vasc Surg, 48(5): 1092-100
3 Katz
(1997) J Vasc Surg, 25(3): 561-8
4 Lederle
(1999) JAMA, 281(1): 77-82
Two major types of surgical interventions:

Open Repair (OR)1
› Endovascular Aneurysm Repair (EVAR) 2
›
OR
EVAR
- Invasive
- Less invasive
- Higher recovery time
- Lower recovery time
- Normally does not require subsequent
surgeries
- Normally requires subsequent surgeries
(either immediately or for later graft
replacement)
Performed in patients with high risk of post-operative complications
1 Prinssen
2
(2004) N Engl J Med, 351(16): 1607-18
Greenhalgh (2004) Lancet, 364(9437): 843-8

Abdominal aortic aneurysm is one of the 10 major causes
of death in men over 65 years of age in western countries.1

It is important to learn how surgical interventions used and
fatality vary in different regions

knowing which regions have better outcome for either EVAR or OR will
allow us to conclude where the patient has best chances of survival

Comparing Portugal’s mortality rates with those of other
countries will allow us to conclude whether it is better or
worse to be submitted to this type of surgical intervention in
Portugal

Portugal may serve as an example of either what to do or
what not to do in regard to the surgical intervention chosen
for treating an abdominal aortic aneurysm
1 Katz
(1997) J Vasc Surg, 25(3): 561-8

To analyse the baseline characteristics for patients undergoing
endovascular or open abdominal aortic aneurysm repair in
Portuguese mainland state hospitals during the studied period

To compare the choice of surgical approach (EVAR or OR)
among the different regions;

To determine the most frequent type of abdominal aortic
aneurysm (ruptured or non-ruptured) submitted to surgical
intervention in Portuguese mainland state hospitals of each
region;

To calculate and compare the in-hospital mortality associated:



with ruptured / non-ruptured aneurysms
with the different surgical approaches (OR and EVAR)
with the different regions
1.
Introduction
1.
2.
3.
2.
Background
Justification
Aims
Participants and Methods
1.
2.
3.
4.
5.
Study participants
Study design
Data collection methods
Variable descriptions
Statistical analysis
3.
Results
4.
Conclusion and Discussion
5.
References
1.
Introduction
1.
2.
3.
Background
Justification
Aims
Participants and Methods
2.
1.
2.
3.
4.
5.
Study participants
Study design
Data collection methods
Variable descriptions
Statistical analysis
3.
Results
4.
Conclusion and Discussion
5.
References

All Portuguese mainland state hospitals inpatients episodes
› Diagnosed with ruptured/non-ruptured abdominal aortic
aneurysm
› Submitted to either OR or EVAR for these conditions

Database:
› records from all Portuguese mainland state hospitals
› period 2000-2009*
* incomplete data (from Jan-Sep)
1.
Characterization of the population by:


Gender
Age
2.
Yearly ratio ruptured/non-ruptured surgeries
3.
Yearly ratio OR/EVAR
4.
In-hospital mortality

Patient hospital episode administrative database using the DRG
classification system
ICD-9-CM codes used for patient selection
Diseases and Injuries Codes
441.3
Ruptured aneurysm of the abdominal aorta
441.5
Aortic aneurysm unspecified site ruptured
441.4
Aneurysm of the abdominal aorta, without mention of rupture
441.9
Aortic aneurysm of unspecified site without mention of rupture
Ruptured aneurysm
Non-ruptured aneurysm
Procedures Codes
39.51
Clipping of aneurysm
39.52
Other repair of aneurysm
39.25
Aorta iliac femoral bypass
38.44
Resection of vessel with replacement, abdominal aorta
39.71
Endovascular implantation of graft in abdominal aorta
39.79
Other endovascular repair (of aneurysm) of other vessels
Open repair (OR)
Endovascular repair (EVAR)

Gender (raw data)

Age (raw data)

Type of Aneurysm (recoded variable)
• ruptured vs. non-ruptured

Type of surgical intervention (recoded variable)
• OR vs. EVAR

Mortality (raw data)

Location of mainland state hospital (recoded variable)
• Division in 5 regions (Norte, Centro, Lisboa, Alentejo and
Algarve) according to the NUTS II classification
Gender
Age
Mortality
Chi square test
Kruskal-Wallis test
Chi square test
Mann-Whitney U paired
test
Fisher’s exact test
(Holm-Bonferroni adjustment)
(for small samples)
1.
Introduction
1.
2.
3.
Background
Justification
Aims
Participants and Methods
2.
1.
2.
3.
4.
5.
Study participants
Study design
Data collection methods
Variable descriptions
Statistical analysis
3.
Results
4.
Conclusion and Discussion
5.
References
1.
Introduction
1.
2.
3.
Background
Justification
Aims
Participants and Methods
2.
1.
2.
3.
4.
5.
Study participants
Study design
Data collection methods
Variable descriptions
Statistical analysis
3.
Results
4.
Conclusion and Discussion
5.
References
2474 repairs
200 excluded (date of surgery unregistered)
n = 2274
Norte
n = 656
28,85%
Centro
n = 349
15,35%
Lisboa
n = 1249
54,92%
Alentejo
n = 19
0,84%
Algarve
n=1
0,04%
Baseline characteristics for patients undergoing endovascular or open
abdominal aortic aneurysm repair in Portuguese mainland state
hospitals during the studied period
Characteristics
Age, mean (SD), y
Male gender, %
(No.)
Norte (n=656)
Centro (n=349)
Lisboa (n=1249)
Alentejo (n=19)
Algarve (n=1)*
OR
EVAR
OR
EVAR
OR
EVAR
OR
EVAR
OR
EVAR
(n=574)
(n=82)
(n=335)
(n=14)
(n=1112)
(n=137)
(n=19)
(n=0)
(n=1)
(n=0)
71 ± 9
73 ± 7
71 ± 9
69 ± 9
71 ± 9
74 ± 8
73 ± 10
-
65
-
93.0
95.1
92.2
100
92.4
86.1
89.5
-
100.0
-
(534/574)
(78/82)
(309/335)
(14/14)
(1028/1112)
(118/137)
(17/19)
(-/-)
(1/1)
(-/-)
p**
0.005
0.120
* Lack of cases impaired statistical analysis.
**Calculated using the Kruskal-Wallis test for age and the Chi square test for male gender.
There are significant differences between the age of patients
Patients submitted to EVAR in Lisboa are older than those submitted to OR in Norte,
Centro and Lisboa (determined using Mann-Whitney U paired test and Holm-Bonferroni adjustment)
There are no significant differences between the gender of patients
Norte
Yearly distribution of total Abdominal aortic aneurysm repairs according to
surgical intervention 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009* Total
Count
OR
Centro
Lisboa
47
60
88
74
87
63
35
574
100.0%
100.0%
100.0%
100.0%
100.0%
98.9%
85.1%
87.9%
70.0%
54.7%
87.5%
0
0
0
0
0
1
13
12
27
29
82
0.0%
0.0%
0.0%
0.0%
0.0%
1.1%
14.9%
12.1%
30.0%
45.7%
12.5%
Count
34
51
35
47
60
89
87
99
90
64
656
Count
22
41
35
33
29
33
47
36
40
19
335
100.0%
100.0%
100.0%
100.0%
100.0%
100.0%
100.0%
83.7%
95.2%
79.2%
96.0%
0
0
0
0
0
0
0
7
2
5
14
0.0%
0.0%
0.0%
0.0%
0.0%
0.0%
0.0%
16.3%
4.8%
20.8%
4.0%
Count
22
41
35
33
29
33
47
43
42
24
349
Count
67
40
34
119
152
171
199
154
127
49
1112
100.0%
100.0%
100.0%
100.0%
100.0%
100.0%
100.0%
79.0%
65.1%
63.6%
89.0%
0
0
0
0
0
0
0
41
68
28
137
0.0%
0.0%
0.0%
0.0%
0.0%
0.0%
0.0%
21.0%
34.9%
36.4%
11.0%
Count
67
40
34
119
152
171
199
195
195
77
1249
Count
1
0
2
1
0
6
4
2
2
1
19
100.0%
-%
100.0%
100.0%
-%
100.0%
100.0%
100.0%
100.0%
100.0%
100.0%
0
0
0
0
0
0
0
0
0
0
0
0.0%
-%
0.0%
0.0%
-%
0.0%
0.0%
0.0%
0.0%
0.0%
0.0%
Count
1
0
2
1
0
6
4
43
42
24
19
Count
0
0
0
0
0
0
0
0
1
0
1
-%
-%
-%
-%
-%
-%
-%
-%
100.0%
-%
100.0%
0
0
0
0
0
0
0
0
0
0
0
-%
-%
-%
-%
-%
-%
-%
-%
0.0%
-%
0.0%
Count
0
0
0
0
0
0
0
0
1
0
1
Count
124
132
106
200
241
298
324
279
233
104
2041
100.0%
100.0%
100.0%
100.0%
100.0%
99.7%
96.1%
82.3%
70.6%
62.7%
89.8%
0
0
0
0
0
1
13
60
97
62
233
0.0%
0.0%
0.0%
0.0%
0.0%
0.3%
3.9%
17.7%
29.4%
37.3%
10.2%
124
132
106
200
241
299
337
339
330
166
2274
%
OR
%
Count
EVAR
%
Total
OR
%
Count
EVAR
%
Total
Alentejo
35
Count
Total
OR
%
Count
EVAR
%
Total
Algarve
51
%
EVAR
OR
%
Count
EVAR
%
Total
Total
34
OR
%
Count
EVAR
%
Total
Count
Norte
Yearly distribution of total Abdominal aortic aneurysm repairs according to
surgical intervention 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009* Total
Count
34
51
35
47
60
88
74
87
63
35
574
100.0%
100.0%
100.0%
100.0%
100.0%
98.9%
85.1%
87.9%
70.0%
54.7%
87.5%
0
0
0
0
0
1
13
12
27
29
82
0.0%
0.0%
0.0%
0.0%
0.0%
1.1%
14.9%
12.1%
30.0%
45.7%
12.5%
Count
34
51
35
47
60
89
87
99
90
64
656
Count
22
41
35
33
29
33
47
36
40
19
335
100.0%
100.0%
100.0%
100.0%
100.0%
100.0%
100.0%
83.7%
95.2%
79.2%
96.0%
0
0
0
0
0
0
0
7
2
5
14
0.0%
0.0%
0.0%
0.0%
0.0%
0.0%
0.0%
16.3%
4.8%
20.8%
4.0%
Count
22
41
35
33
29
33
47
43
42
24
349
Count
67
40
34
119
152
171
199
154
127
49
1112
100.0%
100.0%
100.0%
100.0%
100.0%
100.0%
100.0%
79.0%
65.1%
63.6%
89.0%
0
0
0
0
0
0
0
41
68
28
137
0.0%
0.0%
0.0%
0.0%
0.0%
0.0%
0.0%
21.0%
34.9%
36.4%
11.0%
Count
67
40
34
119
152
171
199
195
195
77
1249
Count
1
0
2
1
0
6
4
2
2
1
19
100.0%
-%
100.0%
100.0%
-%
100.0%
100.0%
100.0%
100.0%
100.0%
100.0%
0
0
0
0
0
0
0
0
0
0
0
0.0%
-%
0.0%
0.0%
-%
0.0%
0.0%
0.0%
0.0%
0.0%
0.0%
Count
1
0
2
1
0
6
4
43
42
24
19
Count
0
0
0
0
0
0
0
0
1
0
1
%
-%
-%
-%
-%
-%
-%
-%
OR was the
preferred
method
from
2000-2009
Count
0
0
0
0
0
0
0
-%
100.0%
-%
100.0%
0
0
0
0
OR
%
Count
EVAR
%
Centro
Total
OR
%
Count
EVAR
%
Lisboa
Total
OR
%
Count
EVAR
%
Alentejo
Total
OR
%
Count
EVAR
%
Algarve
Total
OR
EVAR
%
-%
-%
-%
Total
Count
0
0
0
EVARTotalis increasing
since
2005
Count
124
132
106
OR
%
Count
EVAR
%
Total
Count
-%
-%
-%
-%
-%
0.0%
-%
0.0%
0
0
0
0
0
1
0
1
200
241
298
324
279
233
104
2041
100.0%
100.0%
100.0%
100.0%
100.0%
99.7%
96.1%
82.3%
70.6%
62.7%
89.8%
0
0
0
0
0
1
13
60
97
62
233
0.0%
0.0%
0.0%
0.0%
0.0%
0.3%
3.9%
17.7%
29.4%
37.3%
10.2%
124
132
106
200
241
299
337
339
330
166
2274
Yearly percentage of endovascular aneurysm repair in total abdominal
aortic aneurysm surgical interventions in Portuguese mainland state
hospitals
Yearly distribution of total abdominal aortic aneurysm (AAA) surgical
interventions according to aneurysm type
Norte
2000
Non-Ruptured
Centro
Non-Ruptured
Lisboa
Non-Ruptured
Non-Ruptured
Total
2009*
80
70
55
514
73.5%
88.2%
77.1%
76.6%
78.3%
76.4%
70.1%
80.8%
77.8%
85.9%
78.4%
9
6
8
11
13
21
26
19
20
9
142
26.5%
11.8%
22.9%
23.4%
21.7%
23.6%
29.9%
19.2%
22.2%
14.1%
21.6%
Count
34
51
35
47
60
89
87
99
90
64
656
Count
18
29
25
23
17
24
29
26
28
20
239
81.8%
70.7%
71.4%
69.7%
58.6%
72.7%
61.7%
60.5%
66.7%
83.3%
68.5%
4
12
10
10
12
9
18
17
14
4
110
18.2%
29.3%
28.6%
30.3%
41.4%
27.3%
38.3%
39.5%
33.3%
16.7%
31.5%
Count
22
41
35
33
29
33
47
43
42
24
349
Count
44
32
26
86
109
134
151
141
159
56
938
65.7%
80.0%
76.5%
72.3%
71.7%
78.4%
75.9%
72.3%
81.5%
72.7%
75.1%
23
8
8
33
43
37
48
54
36
21
311
34.3%
20.0%
23.5%
27.7%
28.3%
21.6%
24.1%
27.7%
18.5%
27.3%
24.9%
Count
67
40
34
119
152
171
199
195
195
77
1249
Count
88
106
79
146
173
231
245
249
258
132
1707
71.0%
80.3%
74.5%
73.0%
71.8%
77.3%
72.7%
73.5%
78.2%
79.5%
75.1%
36
26
27
54
68
68
92
90
72
34
567
29.0%
19.7%
25.5%
27.0%
28.2%
22.7%
27.3%
26.5%
21.8%
20.5%
24.9%
124
132
106
200
241
299
337
339
330
166
2274
%
%
%
%
%
Total
2008
61
Count
Ruptured
2007
68
%
Total
2006
47
Count
Ruptured
2005
36
%
Total
2004
27
Count
Ruptured
2003
45
%
Total
2002
25
Count
Ruptured
Total
Count
2001
Count
The ratio Non-ruptured/Ruptured AAA is approximately 3/1
Yearly percentage of non-ruptured aneurysm repairs in total abdominal
aortic aneurysms surgical interventions in Portuguese mainland state
hospitals
Regional distribution of in-hospital mortality according to type of abdominal
aortic aneurysm and repair procedure
AAA /Surgery types
Non-
OR
Norte
p*
(n=656)
Centro
(n=349)
EVAR
OR
Ruptured
EVAR
(n=1249)
p**
Alentejo
Algarve
Total
(n=19)***
(n=1)***
(n=2274)
6.2%
7.0%
7.9%
18.8%
-
7.3%
(27/438)
(16/228)
(64/815)
(3/16)
(-/-)
(110/149
0.102
ruptured
p*
Lisboa
0.564
7)
0.836
1.3%
9.1%
7.3%
-
-
5.2%
(1/76)
(1/11)
(9/123)
(-/-)
(-/-)
(11/210)
45.6%
54.2%
50.8%
66.7%
100%
50.4%
(62/136)
(58/107)
(151/297)
(2/3)
(1/1)
(274/544)
-
-
65.2%
(-/-)
(-/-)
(15/23)
83.3%
0.100
(5/6)
66.7%
(2/3)
1.000
57.1%
(8/14)
0.645
*Calculated using the Fisher’s exact test.
**Calculated using the Chi square test.
***Lack of cases impaired statistical analysis.
No significant differences on mortality were found between OR and EVAR
Tendency for EVAR to present better outcome in non-ruptured AAAs
Tendency for OR to present better outcome in ruptured AAAs
p**
0.265
0.163
1.
Introduction
1.
2.
3.
Background
Justification
Aims
Participants and Methods
2.
1.
2.
3.
4.
5.
Study participants
Study design
Data collection methods
Variable descriptions
Statistical analysis
3.
Results
4.
Conclusion and Discussion
5.
References
1.
Introduction
1.
2.
3.
Background
Justification
Aims
Participants and Methods
2.
1.
2.
3.
4.
5.
Study participants
Study design
Data collection methods
Variable descriptions
Statistical analysis
3.
Results
4.
Conclusion and Discussion
5.
References
Gender/Age

Men were the most affected gender undergoing surgery (9 to 1)
 AAAs 3 times more frequent in men
 AAAs larger in men

Patients undergoing EVAR in Lisboa are significantly older than
those undergoing OR in Norte, Centro and Lisboa
 triage process where high-risk, older patients are selected for
EVAR
Open Repair vs. Endovascular Aneurysm Repair

Increase in total number of surgeries

OR as the preferred surgical intervention

Increase in the use of EVAR
Open Repair vs. Endovascular Aneurysm Repair

EVAR may present better outcome in non-ruptured aneurysms
(not confirmed by statistical analysis)

EVAR in ruptured aneurysm seemingly increases in-hospital
mortality
 only performed as last resort, on patients where survival odds
are already low
Ruptured aneurysm vs. non-ruptured aneurysm

Most surgical interventions performed on non ruptured
aneurysm
 most patients with ruptured aneurysm don’t reach
hospital alive

Elective surgery presents low in-hospital mortality

Treating an aneurysm prior to its rupture is the main
factor for achieving lower mortality rates
Prior published in-hospital and 30-day mortalities following treatment of ruptured and non-ruptured abdominal aortic
aneurysms
Year of
publication
Country of origin
Patients
operated (n)
Outcome
2004
Spain
83
Wahlgren and Malmstedt [18]
2008
Sweden
Wanhainen [19]
2008
Prinssen [20]
Study
OR
30-day mortality
3.7
6.6
3831
30-day mortality
1.8
2.8
Sweden
7175
30-day mortality
2.5
4.1
2004
Netherlands/Belgium
345
30-day mortality
1.2
4.6
Greenhalgh [21]
2008
UK
1082
30-day mortality
1.7
4.7
Schermerhorn [22]
2008
USA
45660
30-day mortality
1.2
4.8
Lederle [23]
2009
USA
881
In-hospital mortality
0.5
3.0
McPhee [24]
2007
USA
183387
In-hospital mortality
1.0
4.5
Leon [25]
2005
USA
12399
In-hospital mortality
2.3
6.0
5.2
7.3
1.3
9.1
7.3
-
6.2
7.0
7.9
18.8
30-day mortality
15.2
36.1
Non- Ruptured Aneurysm
Garcia-Madrid
[17]
Present study (total)
Norte
Centro
Lisboa
Alentejo
Wanhainen [19]
Ruptured Aneurysm
Mortality (%)
EVAR
1707
2008
Sweden
514
239
938
16
3516
Visser [26]
2009
Netherlands
201
30-day mortality
25.9
39.9
Starnes
[27]
2010
USA
179
30-day mortality
18.5
57.2
Acosta
[28]
2006
Sweden
162
In-hospital mortality
33.9
45.2
2007
UK
126
In-hospital mortality
32.7
51.4
2009
USA
700
In-hospital mortality
45.1
52.4
2007
USA
37016
In-hospital mortality
29.0
38.2
Greco [31]
2006
USA
5798
In-hospital mortality
39.3
47.7
Leon [25]
2005
USA
2118
In-hospital mortality
36.4
42.4
65.2
50.4
83.3
66.7
57.1
-
45.6
54.2
50.8
66.7
Sharif
[29]
Vogel [30]
McPhee
[24]
To be
published
Portugal
Present study (total)
Norte
Centro
Lisboa
Alentejo
In-hospital mortality
567
To be
published
Portugal
142
110
311
3
In-hospital mortality
In-hospital mortality rates

Higher than those of other Western countries

Exception: Norte
Limitations

Low number of patients undergoing EVAR could explain high p values obtained,
impairing statistical confirmation of the EVAR better outcome, especially in Norte

The cause of death of patients with ruptured abdominal aortic aneurysm is often
attributed to other pathologies – numbers may be underestimated

Surgeons’ personal testimonies refer the use of EVAR since the beginning of the
decade – directly contradicts the data
›
Flawed insertion of the ICD-9-CM codes on database
›
Lack of specific training for using the software
›
Complex procedures to registry data
1.
Introduction
1.
2.
3.
Background
Justification
Aims
Participants and Methods
2.
1.
2.
3.
4.
5.
Study participants
Study design
Data collection methods
Variable descriptions
Statistical analysis
3.
Results
4.
Conclusion and Discussion
5.
References
1.
Introduction
1.
2.
3.
Background
Justification
Aims
Participants and Methods
2.
1.
2.
3.
4.
5.
Study participants
Study design
Data collection methods
Variable descriptions
Statistical analysis
3.
Results
4.
Conclusion and Discussion
5.
References
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