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PLOS One logoLink to PLOS One
. 2021 Dec 2;16(12):e0260690. doi: 10.1371/journal.pone.0260690

Quality-adjusted life year comparison at medium term follow-up of endovascular versus open surgical repair for abdominal aortic aneurysm in young patients

Eunae Byun 1, Tae-Won Kwon 2,*, Hyangkyoung Kim 2, Yong Pil Cho 2, Youngjin Han 2, Gi Young Ko 3, Min-Jae Jeong 4
Editor: Robert Jeenchen Chen5
PMCID: PMC8639078  PMID: 34855851

Abstract

Objectives

This study aimed to compare the quality of life and cost effectiveness between endovascular aneurysm repair (EVAR) and open surgical repair (OSR) in young patients with abdominal aortic aneurysm (AAA).

Design

This was a single-center, observational, and retrospective study.

Materials and methods

A retrospective analysis was conducted of patients with AAA, who were <70 years old and underwent EVAR or OSR between January 2012 and October 2016. Only patients with aortic morphology that was suitable for EVAR were enrolled. Data on the complication rates, medical expenses, and expected quality-adjusted life years (QALYs) were collected, and the cost per QALY at three years was compared.

Results

Among 90 patients with aortic morphology who were eligible for EVAR, 37 and 53 patients underwent EVAR and OSR, respectively. No significant differences were observed in perioperative cardiovascular events and death between the two groups. However, during the follow-up period, patients undergoing OSR showed a significantly lower complication rate (hazard ratio [HR] = 0.11; P = .021). From the three-year cost-effectiveness analysis, the total sum of costs was significantly lower in the OSR group (P < .001) than that in the EVAR group, and the number of QALYs was superior in the OSR group (P = .013). The cost per QALY at three years was significantly lower in the OSR group than that in the EVAR group (mean: $4038 vs. $10 137; respectively; P < .001)

Conclusions

OSR had lower complication rates and better cost-effectiveness than EVAR Among young patients with feasible aortic anatomy.

Introduction

Currently, endovascular aneurysm repair (EVAR) and open surgical repair (OSR) are the only options for treating abdominal aortic aneurysm (AAA). Previous randomized controlled trials (RCTs) that compared the outcomes of EVAR and OSR have reported perioperative, 30-day, and short-term outcomes of EVAR to be superior than those of OSR, but other trials reported OSR to be a safer option than EVAR in terms of long-term outcomes [14]. The unfavorable long-term outcomes of EVAR are owing to the various complications and situations that eventually require reintervention. The possibility of an endoleak increases over time with morphological changes in the aorta. Even type 2 endoleaks (T2ELs), which are considered benign, have the potential to expedite the occurrence of other types of endoleaks, if presented with sac expansion [5].

EVAR and OSR have their respective advantages and disadvantages, which are elaborated in the National Institute for Health and Care Excellence guidelines [6]. This set of guidelines recommends OSR as the standard treatment for AAA. It emphasizes that if patients with AAA choose to undergo EVAR, the clinicians should ensure that the patients understand the potential complications and the possibility of secondary intervention that are associated with EVAR [6].

EVAR is the preferable choice for older patients with comorbidities because of its desirable periprocedural outcomes [14]. However, in younger patients who have longer life expectancies and for whom age is not a factor, the selection of treatment is less obvious, for the aforementioned reasons. This dilemma becomes more prominent when the aortic morphology of young patients makes them eligible for both EVAR and OSR. In these cases, health care professionals need to consider the health-related quality of life (HRQOL) and the cost of each surgical method when making the decision.

This study compared the quality-adjusted life years (QALYs) and medical expenses and reported the complication rates, including the reinterventions associated with increased cost, in young patients (<70 years old) with an aortic anatomy that is eligible for both EVAR and OSR. The results of this study aim to offer a foundation for the decision-making process of whether to perform an elective EVAR or OSR in young patients with AAA.

Methods

Study design and patient selection

We conducted a retrospective analysis on a prospectively compiled and computerized database of consecutive patients with AAA. All patients under 70 years of age who underwent elective EVAR or OSR for AAA between January 2012 and October 2016 and had their follow-ups terminated on March 30, 2020, were included. The indication for AAA repair was based primarily on the maximum diameter of the aneurysm, which was at least 5.5 cm for males and 5.0 cm for females [7].

All patients in the present study underwent preoperative contrast-enhanced computed tomography (CT). Following the analysis of the CT images by a professional radiologist at the hospital, one of the authors analyzed whether the aortic morphology conformed to a composite list of instructions for the inclusion of only patients with the aortic morphology that was suitable for EVAR and OSR: aneurysm infrarenal neck length ≥10 mm, infrarenal aortic neck angulation <60 degrees, neck diameter between 18 and 28 mm, and common iliac artery distal fixation length ≥10 mm [8]. Patients meeting one or more of the following exclusion criteria were not eligible to participate in this study 1) patients with aortic morphology that is not feasible for EVAR; 2) patients requiring emergency surgery due to a rupture or infection and requiring only OSR owing to the inflammation (only degenerative AAA were included); 3) patients who underwent other types of surgery for a different illness (e.g., cancer) with AAA treatment; 4) foreign patients (because of a different cost system); and 5) patients at high risks from general anesthesia (GA) based on cardiac, pulmonary, and neurologic examination, because they could only undergo EVAR under local anesthesia (LA) (Fig 1) were excluded. The possibility of general anesthesia was evaluated by collecting the opinions of experts in each department, and patients evaluated as high-risk groups during GA were excluded. Even when EVAR was always performed under LA, we prepared for GA, to be possible just in case.

Fig 1. Enrollment of the study.

Fig 1

EVAR, Endovascular aneurysm repair; OSR, open surgical repair; LA, local anesthesia; GA general anesthesia.

The choice between EVAR and OSR was based on patient preference. After preoperative evaluation, the patients made a decision after consulting with the doctor in charge (vascular surgeon and radiologist) about the treatment options [9]. When performed under LA, the patients had the advantage of reducing the risk from GA. However, patients had to lie on a firm bed during the long procedures and became anxious. The patients carefully considered the strengths and weaknesses of each treatment and chose accordingly.

This study was approved by the institutional Review Board of Asan Medical Center (2020–0215). The requirement for informed consent was waived owing to the retrospective nature of this study.

Procedure details

All OSRs were performed by two vascular surgeons. There was no difference in following a single protocol in the same hospital setting. EVARs were performed by one vascular surgeon or two radiologists; they had often operated together and discussed all results together. Among the EVAR procedures, 48.6% (18/37) were performed by radiologists and a percutaneous approach was used under inguinal LA in an intervention room. The remaining EVAR (19/37; 51.4%) procedures were performed by surgeons in operating rooms using bilateral surgical cutdown under GA.

The OSR procedures were performed using a transperitoneal approach with an incision from the xiphoid process to the pubis. The standard procedure involved infrarenal clamping and reconstruction by performing interposition with a bifurcated graft. Gortex (W. L. Gore & Association, Flagstaff, AZ, USA) and Dacron (Hemagard, Maquet Getinge Group, Rastatt Germany) grafts were used in 12 (22.6%) and 41 cases (77.4%), respectively.

For EVAR, different commercially available stent-graft devices were used. Endurant (Medtronic Inc., Santa Rosa, CA, USA) devices were used in most cases (28/37; 75.7%), while Zenith (Cook Medical, Bloomington, IN, USA) and Excluder (W. L. Gore & Associations, Flagstaff, AZ, USA) devices were used in eight (21.6%) and one (2.7%) patients, respectively. Hemostasis was achieved using Perclose Prostar XL or Proglide devices (Abbott Vascular, Redwood City, CA, USA) in all patients undergoing EVAR under LA.

Follow-up

The frequency of outpatient visits and follow-up tests were based on an expert’s opinion. The follow-up protocol included a physical examination and CT imaging. The patients who underwent EVAR visited the hospital regularly at 30 days, 6 months, 1 year, and every 2 years thereafter. Enhanced CT (aortic dissection CT or lower extremity CT angiography) was performed before visiting the outpatient department. In contrast, the patients who underwent OSR visited the outpatient department for medication every 6 months. CT was conducted only for patients who presented with other aortic aneurysms, abnormal symptoms, or abnormal findings on physical examination.

Outcomes

The primary outcomes that were analyzed included medical expenses, QALYs, and cost per QALY at three years. The secondary outcomes considered were readmission-requiring complication rates, including reintervention that resulted in increased cost and change in QALY, all-cause death, and aneurysm-related death in the perioperative period (30 days) and during follow-up.

The medical expenses comprised costs for in-hospital care, routine follow-ups, and complications. The data for the in-hospital and complication-related costs was extracted from the records of the patients’ total medical expenses that were not adjusted for health care benefits. The total sum of costs included the doctor’s fees; costs of equipment for operations or interventions, patient rooms, imaging examinations, and laboratory examinations; and other costs. On the other hand, data on the follow-up costs that were extracted from the records of unit costs of a routine aortic dissection CT ($393 in 2012) were based on the costs in our center. The price was based on the year of 2012 (the year in which the recruitment for this study started), and all costs were collected in South Korean won. The costs in future years were discounted at the rates of 1.3%, 2.6%, 3.3%, 4.3%, 6.3%, 7.9%, 8.3%, and 10.0% per year from 2013 to 2020 (according to the Korean Statistical Information Service consumer price index) [10]. Subsequently, all costs were expressed in US dollar (USD, $) at the exchange rate prevalent in 2012 [11].

We used the QALYs to calculate the HRQOL. The HRQOL values are recommended to be calibrated using social preference weights elicited from the general population. Thus, we used quality weights from the Euro Quality of Life–5 Dimensions (EQ-5D) records. We used the average score of EQ-5D during the first three years after the primary procedure by contacting and enquiring the patients through the phone during the investigation period. The following formula indicates the South Korean population-based preference weights for the EQ-5D [1215]: Y = 1 - (0.05 + 0.096 × M2 + 0.418 × M3 + 0.046 × SC2 + 0.136 × SC3 + 0.51 v UA2 + 0.208 × UA3 + 0.037 × PD2 + 0.151 × PD3 + 0.043 × AD2 + 0.158 × AD3 + 0.05 × N3), where M2, mobility level 2; M3, mobility level 3; SC2, self-care level 2; SC3, self-care level 3; UA2, usual activity level 2; UA3, usual activity level 3; PD2, pain or discomfort level 2; PD3, pain or discomfort level 3; AD2, anxiety or depression level 2; AD3, anxiety or depression level 3; and N3, any dimension on level 3.

Statistical analysis

Categorical variables were compared using the Pearson chi-square tests or Fisher’s exact test, as appropriate. Continuous variables were analyzed using the Student’s t-test and Wilcoxon Mann–Whitney U test after the normality test. Costs were presented using the mean values rather than the median values, which is considered appropriate in health economic evaluations.

For comparison of the complications, the possible differences between the groups were tested using recurrent event models (Andersen and Gill model with a robust sandwich estimator). Hazard ratio (HR) was adjusted for age because the age of the OSR group was significantly lower according to the analysis of the patients’ basic characteristics.

The cardiovascular events and death rates were calculated by the Kaplan–Meier survival analysis and were compared using the log-rank test.

P < .05 was considered as statistically significant. All statistical analyses were performed using IBM SPSS Statistics for Windows, version 21.0 (IBM Corp, Armonk, NY, USA).

Results

Patient characteristics

A total of 434 patients underwent EVAR or OSR for AAA between January 2012 and October 2016. Among these, 257 patients were excluded from the present study as they were over the age of 70 years. From the remaining patients, 59 and 118 patients underwent EVAR and OSR, respectively. After applying the exclusion criteria of patients with aortic morphology feasible for only EVAR and those at high risk from GA, we finally included 90 patients in this study. Of these 90 patients, 37 (41.1%) had undergone an EVAR and 53 (58.9%) had undergone an OSR. (Fig 1) A total of 53 patients, who had undergone an OSR, had aortic morphology that was feasible for an EVAR but had chosen to undergo an OSR.

In this study, 83 of 90 patients were male (92.2%), and the median age was 64.0 years (interquartile range, 60.8–66.3 years). The median age in the EVAR group was higher than that in the OSR group (66.0 vs. 63.0 years, respectively; P < .001); however, other demographic factors and comorbidities did not significantly differ between the groups. Preoperative CT showed a mean aortic maximum diameter of 58.6 ± 10.8 mm; 57.8 ± 9.5 mm in the EVAR group and 59.2 ± 11.6 mm in the OSR group (P = .556; a difference that was not statistically significant). Other anatomical details also showed no significant differences between the two groups (Table 1).

Table 1. Baseline demographics and aortic aneurysm morphological characteristics.

Total (n = 90) EVAR (n = 37) OSR (n = 53) P-value
Baseline characteristics
Age (years) 64.0 (60.8–66.3) 66.0 (63.0–68.0) 63.0 (58.5–65.0) < .001
Male sex 83 (92.2) 34 (91.9) 49 (92.5) >.05§
BMI (kg/m 2 ) 24.9 (± 3.0) 25.1 (± 3.4) 24.8(± 2.7) .632
Smoking 37 (41.1) 14 (37.8) 23 (43.4) .598
Hypertension 48 (53.3) 16 (43.2) 32 (60.4) .109
DM 16 (17.8) 5 (13.5) 11 (20.8) .377
COPD 8 (8.9) 4 (10.8) 4 (7.5) .712§
CKD 15 (16.7) 8 (21.6) 7 (13.2) .292
PAOD 1 (1.1) 0 (0) 1 (1.9) >.05§
CAD 30 (33.3) 10 (27.0) 20 (37.7) .289
HF 2 (2.2) 1 (2.7) 1 (1.9) >.05§
Cancer Hx. 9 (10.0) 6 (16.2) 3 (5.7) .153§
CVA 7 (7.8) 3 (8.1) 4 (7.5) >.05§
CCI 2.0 (1.0–3.0) 2.0 (1.0–3.0) 2.0 (1.0–3.0) .795*
Aortic aneurysmal morphology
Maximum aortic diameter (mm) 58.6 (± 10.8) 57.8 (± 9.5) 59.2 (± 11.6) .556
Aortic neck length (mm) 36.3 (± 12.1) 35.4 (± 15.2) .761
Aortic neck width (mm) 20.6 (± 2.5) 20.1 (± 1.9) .404
Infrarenal aortic angulation (°) 31.7 (± 25.4) 36.8 (± 28.5) .385
Shorter CIA length (mm) 35.9 (± 14.8) 33.0 (± 12.5) .084

Values in parentheses are percentages, unless age, BMI, CCI, and aortic aneurysmal morphology; age and CCI are reported as median (interquartile range); BMI and aortic aneurysmal morphology values are reported as means (± standard deviation).

†Pearson chi-square test, except.

‡Student’s t-test.

§Fisher’s exact test.

* Mann-Whitney U test.

EVAR, Endovascular aneurysm repair; OSR, open surgical repair; BMI, body mass index; DM, diabetes mellitus; COPD, chronic obstructive pulmonary disease; CKD, chronic kidney disease; PAOD, peripheral arterial occlusive disease CAD, coronary artery disease; HF, heart failure; Cancer Hx., cancer history; CVA, cerebrovascular accident; CCI, Charlson Comorbidity Index; CIA, common iliac artery.

Follow-up results

The median follow-up duration was 52 months (interquartile range, 42.8–70.5 months); 49 months (interquartile range, 41.5–73.0 months) in the EVAR group and 55 months (interquartile range, 44.0–69.5 months) in the OSR group. Perioperative myocardial infarction (MI) occurred only in the OSR group (n = 1; P = .403), but no perioperative cerebrovascular accidents (CVAs) or deaths (all-cause or aneurysm-related) occurred in either group. The differences in the rates of late MI, CVA, and death (all-cause, aneurysm-related) between EVAR and OSR were negligible (MI, P = .095; CVA, P = .403; aneurysm-related death, P = .229; all-cause death, P = .153). One aneurysm-related death (AAA rupture) occurred in the EVAR group 31 months after the procedure (Table 2). Fig 2 shows the survival curves. There was no statistically significant difference in all-cause death (P = .153) and aneurysm-related death (P = .229) between the EVAR and OSR groups, but there was a significant difference in complication (requiring admission)-free survival (P = .020).

Table 2. Cardiovascular events and death rates in perioperative and during the follow-up period.

Perioperative outcomes Follow-up outcomes
EVAR (n = 37) OSR (n = 53) P-value EVAR (n = 37) OSR (n = 53) P-value
MI 0 (0) 1 (1.9) .403 6 (16.2) 3 (5.7) .095
CVA 0 (0) 0 (0) NA 0 (0) 1 (1.9) .403
Aneurysm-related death 0 0 NA 1 (2.7) 0 (0) .229
All-cause death 0 0 NA 6 (16.2) 4 (7.5) .153

Values in parentheses are percentages.

†Log-rank test.

EVAR, Endovascular aneurysm repair; OSR, open surgical repair; MI, myocardial infarction; CVA, cerebrovascular accident; NA, not applicable.

Fig 2. Survival curves.

Fig 2

EVAR, Endovascular aneurysm repair; OSR, open surgical repair.

At the median follow-up time of 52 months (interquartile range, 42.8–70.5 months), reinterventions had been performed in 13 patients, among which eight patients had undergone EVAR (21.6%). Readmission-requiring complications occurred in three cases in three patients who had undergone OSR (5.7%); the difference was statistically significant between EVAR and OSR (HR, 0.11; 90% confidence interval [CI], 0.03–0.45; P = .0022; Table 3). This result was adjusted for age as this factor differed significantly between the two groups (P < .001; Table 1). One patient in the EVAR group required three reinterventions, and three patients required two reinterventions each. In detail, of the 13 reinterventions performed in the EVAR group, six involved embolization due to T2EL and type 1a endoleak (T1aEL). A stent graft insertion due to type 1b endoleak (T1bEL), T2EL, and limb occlusion were observed in four cases. Open conversions due to T2EL or endotension were observed in two cases; open conversions were included in the reintervention count. In the OSR group, there were three cases of complications. One case involved conservative care under readmission due to mechanical ileus and two cases involved herniorrhaphies due to incisional hernias. The three cases were considered as first complications (Table 4).

Table 3. Complication (requiring readmission) rates during follow-up.

No. of complications EVAR OSR Recurrent events modela
No. of events Average time to event (mns) No. of events Average time to event (mns) HR (95% CI)b P-value
1st complication (including reintervention) 8 23.25 3 10 .11 (0.03–0.45) .0022
2nd reintervention 4 19.75
3rd reintervention 1 1

HR for OSR group (reference group = EVAR).

aAndersen and Gill model with robust sandwich estimator.

bAdjusted for age.

EVAR, Endovascular aneurysm repair; OSR, open surgical repair; mns, months; HR, hazard ratio; CI, confidence interval.

Table 4. Details of complications and medical expenses.

EVAR
No. of patients Indication for reintervention Reintervention Medical expense ($) Reintervention-free duration (mns)
1 T2EL Embolization 4561 15
T2EL (surgery) Open graft interposition 12 304 24
2 T2EL Embolization 3013 34
T2EL Embolization 2725 58
T1bEL Limb graft extension 6977 59
3 T1bEL Stent graft insertion 19 955 66
4 T2EL Embolization 5693 45
5 T1aEL Embolization 3315 4
6 T2EL Stent graft insertion 5812 20
Endotension (surgery) Open proximal reinforce and redo EVAR 17 235 39
7 Limb occlusion Thrombolysis and stent graft insertion 13 226 1
8 T1aEL Embolization 7658 1
T1aEL Aortic cuff implantation 4704 28
Total expense of intervention 107 178
Mean expense per intervention 8245
OSR
No. of patients Indication for admission Treatment Medical expense ($) Treatment-free duration (mns)
1 Hernia Mesh herniorrhaphy 5149 20
2 Mechanical ileus Conservative care 1386 1
3 Hernia Hernia repair 3421 9
Total expense of complication 9956
Mean expense per complication 3319

EVAR, Endovascular aneurysm repair; OSR, open surgical repair; T2EL, type 2 endoleak; T1bEL, type 1b endoleak; T1aEL, type 1a endoleak; mns, months.

Both the EVAR and OSR groups included patients with complications that required no readmission or reintervention. For example, in the six patients from the EVAR group, T2ELs were found that either disappeared on their own or lacked sac growth. In the OSR group, three patients were diagnosed with retrograde ejaculation, and received symptomatic treatment. Complications, such as graft infection, distal embolization, and renal infarction, were not found in this study.

Cost analysis

The costs of hospitalization for the primary procedure, follow-up, and complications were accumulated and calculated annually. As the year passed, the difference between EVAR and OSR increased. It was found that not only the in-hospital cost but also the cumulative cost at one, two, and three years was statistically significantly higher in EVAR compared with that of OSR. Our three-year HRQOL analysis showed that the QALY at three years was significantly higher in the OSR group (mean, 2.69; 95% CI, 2.69–2.82) compared with that of the EVAR group (mean, 2.49; 95% CI, 2.27–2.70) (P = .013). Overall, the cost per QALY at three years was significantly lower in the OSR group (mean, $4038; range, $2705–$12 545) than that of the EVAR group (mean, $10 137; range, $4454–$68 419) (P < .001; Table 5).

Table 5. Medical expenses and cost per QALY.

EVAR OSR P-value
In-hospital cost, $ 16 498 (10 905–34 296) 10 523 (7615–25 105) < .001
Cost until 1 year, $ 18 014 (11 769–36 132) 10 679 (7615–25 536) < .001
Cost until 2 years, $ 19 140 (12 201–36 564) 10 841 (7615–28 828) < .001
Cost until 3 years, $ 19 279 (12 201–36 564) 10 907 (7615–28 828) < .001
QALY at 3 years (95% CI) 2.49 (2.27–2.70) 2.75 (2.69–2.82) .013
Cost per QALY at 3 years, $ 10 137 (4454–68 419) 4038 (2705–12 545) < .001

Values are reported as mean (range), except when indicated.

Costs are the accumulated values.

† Mann-Whitney U test.

EVAR, Endovascular aneurysm repair; OSR, open surgical repair; QALY, quality-adjusted life year; CI, confidence interval.

In our three-year cost analysis, the in-hospital cost for EVAR (mean, $16 498; range, $10 905–$34 296) vs. OSR (mean, $10 523; range, $7615–$25 105), and the follow-up costs for EVAR (mean, $1307; range, $1295–$1727) vs. OSR (mean, 196; range, $0–$2591) were significantly lower (both P < .001) in the EVAR group. The complication-associated costs were lower in the OSR group (mean, $188; range, $0–$5149) than those in the EVAR group (mean, $1474; range, $0–$16 864); however, the difference was not statistically significant (P = 0.087; Table 6).

Table 6. Cumulative annual cost.

EVAR (n = 37), $ OSR (n = 53), $ P-value
In-hospital cost 16 498 (10 905–34 296) 10 523 (7615–25 105) < .001
Follow-up cost at 1 yr 864 (864–864) 65 (0–864) < .001
Complication cost at 1 yr 652 (0–13 168) 91 (0–3421) .358
Cost until 1 yr 18 014 (11 769–36 132) 10 679 (7615–25 536) < .001
Follow-up cost at 2 yrs 1295 (1295–1295) 130 (0–1727) < .001
Complication cost at 2 yrs 1347 (0–16 864) 188 (0–5149) .087
Cost until 2 yrs 19 140 (12 201–36 564) 10 841 (7615–28 828) < .001
Follow-up cost at 3 yrs 1307 (1295–1727) 196 (0–2591) < .001
Complication cost at 3 yrs 1474 (0–16 864) 188 (0–5149) .087
Cost until 3 yrs 19 279 (12 201–36 564) 10 907 (7615–28 828) < .001

Values are reported as mean (range).

† Mann-Whitney U test.

EVAR, Endovascular aneurysm repair; OSR, open surgical repair; yr, year.

Discussion

Since the first successful EVAR procedure in the 1990s, the application of EVAR for AAA has steadily increased [16]. This popularity is a result of the numerous studies that demonstrated desirable perioperative and short-term outcomes for EVAR compared with those for OSR [2,1720]. However, subsequent studies on the same topic suggest little difference in the long-term outcomes between EVAR and OSR [1,4,15,17,18,21,22]. Some studies have reported better long-term outcomes for OSR [3,20,23,24], adding more contradictory data to this controversial topic. Our center also reported the superiority of OSR in long-term outcome [24]. The main reason for the EVAR long-term outcome being lower than OSR long-term outcome was the reintervention rate. The high reintervention rate was related with the high cost and QALY. Young populations who have a longer life expectancy than old populations are more exposed to chances for reintervention, leading to a higher cost and lower QALY. These young patients with AAA, who fit both OSR and EVAR, were our subject of investigation into the reintervention rate, medical expenses, and QALY. As a result, the three-year complication rate was 0.11 for HR (90% CI, 0.03–0.45; P = .0022), which was lower in the OSR than EVAR. For the three-year medical expenses, it was lower (P<0.001) in the OSR group (mean, $19 279; range; $7615–28 828) than that in the EVAR group (mean, $19 279; range, $12 200–$36 564). In addition, the three-year QALY was higher for OSR (2.75; 95% CI, 2.69–2.82) than that for EVAR (2.49; 95% CI, 2.27–2.70) (P = .013).

The patients diagnosed with AAA are at high risk of the onset of numerous comorbidities and are not expected to have average life expectancies that are comparable to those of their healthy counterparts. Thus, we need to seriously consider the HRQOL of the patients after their treatment for AAA. This study calculated the QALY at three years to assess the HRQOL. We observed higher scores in patients from the OSR group compared with those from the EVAR group, with a gain of .26 QALY at three years (Table 7). Ulug et al. reported a gain of .166 QALY at three years in patients with ruptured AAA (95% CI, 0.002–0.331), while there were differences in outcomes between ruptured and elective AAA [15]. Prinssen et al. reported a significant increase in the EQ-5D score at 6 months post-operation for OSR compared with that for EVAR, which is comparable to the results of our study [13].

Table 7. Primary procedure in-hospital cost (price of 2019, exchange rate of 2019).

  unit cost, $ EVAR(GA), $ EVAR(LA), $ OSR, $
Preoperative workup
    Aortic dissection CT 417 417 417 417
    Radiography (chest X-ray) 20 20 20 20
    Echocardiography 290 290 290 290
    Myocardial SPECT 821 821 821 821
    Pulmonary function tests 36 36 36 36
    Laboratory 206 206 206 206
Hospital stay
    Ward bed (per diem) 73 716* 533** 840***
    ICU bed (per diem) 329 0 0 329
Anesthesia
    General anesthesia 414 414 0 414
    CVP monitor 59 59 0 59
    IBP monitor 37 37 0 37
Image during in-hospital
    Aortogram 779 779 779 0
    Aortic dissection CT 417 417 417 417
Equipment
    Endurant-bifurcated body 4024 4024 4024 0
    Endurant-contralateral limb 2445 2445 2445 0
    Balloon 429 429 429 0
    Angiographic catheter 34 34 34 0
    Graduated sizing catheter 137 137 137 0
    Lunderquist wire guide 57 57 57 0
    Raidofocus guide wire 24 24 24 0
    Introducer sheath 27 27 27 0
    Perclose-proglide 249 249 249 0
    Dacron graft (gelsoft bifurcated) 609 0 0 609
    Dacron graft (hemagard) 628 0 0 0
Procedure cost EVAR (GA) 1284 1284 0 0
EVAR (LA) 1254 0 1254 0
OSR 1387 0 0 1387
Overall in-hospital cost   12478 12199 5467

* 73 (unit cost per diem) × 9.8 (mean units, days).

**73 (unit cost per diem) × 7.3 (mean units, days).

***73 (unit cost per diem) × 11.5 (mean units, days).

Unit cost is based on Asan Medical Center.

EVAR, Endovascular aneurysm repair; OSR, open surgical repair; CT, computed tomography; SPECT, single-photon emission computed tomography; ICU, intensive care unit; CVP, central vein pressure; IBP, invasive blood pressure; GA, general anesthesia; LA, local anesthesia.

Not only did OSR result in higher QALYs but also the total sum of costs for OSR at three years was much lower than those for EVAR. The reasons for the lower costs with OSR are as follows: 1) Lower in-hospital cost of the Korea health insurance system; 2) not having to constantly check for endoleaks using CT (as in the case for EVAR); and 3) no costs related to reinterventions. In our study, the HR for complication was 0.11 (reference group = EVAR; P = .0022), consistent with the results of previous RCTs [1,15,25,26]. In addition to the higher total sum of costs and repeated CT procedures for EVAR, the cumulative dose of radiation administered to patients requiring reintervention must also be considered when choosing the operational procedure. OSR may therefore be more suitable for younger patients.

In this study, there was no perioperative mortality in both the EVAR and OSR groups. Both EVAR and OSR had to be studied in young patients who were of the highest similarity as possible; therefore, patients with a life expectancy of less than one year, as well those with unsuitable anatomical morphology, were excluded. This is the most likely reason that no perioperative mortality was observed during this study. Of the 59 patients under the age of 70 years who underwent EVAR during the study period, 14 were excluded owing to their life expectancy of less than one year. Among the 118 patients under the age of 70 years who underwent OSR, no patients had a life expectancy of less than one year. According to this study on patients treated with AAA between 2001 and 2012 at our center, 7 of 352 patients (1.9%) with non-ruptured AAA died in the hospital. The two-,five-, and ten-year survival rates were 94.6%, 89.9%, and 83.4%, respectively [27]. In a study on patients over 40 years of age treated with AAA between 2014 and 2016, the 30-day mortality was 0.8%. This study also discovered that morbidity (including renal complications) and mortality due to OSR were not higher in the suprarenal aortic clamping group than those in the infrarenal aortic clamping group [28].

The mean total lengths of hospital stay were 6.3 and 9.7 days for EVAR and OSR, respectively. This result for EVAR was similar to those of four RCTs (EVAR 1 trial, 8.34 days; DREAM, 6 days; ACE trial, 5.8 days; and OVER, 5 days) [14]. The result for OSR was also similar to that of the ACE trial (8 days) [17]. Previous reports have suggested that EVAR results in lower costs than OSR due to shorter hospital stays in EVAR patients that offset the costly medical bills. The studies also reported lower 30-day mortality and morbidity rates for EVAR than those for OSR, which may also explain the lower costs for EVAR [29]. However, our results indicated a shorter length of in-hospital care for EVAR than that for OSR, and little difference in the 30-day mortality and morbidity rates between them. Despite this, the total sum of costs was lower for OSR. According to Epstein et al. [30], EVAR had long-term cost effectiveness that was comparable to that for OSR in the OVER trial conducted in the US, but was not cost effective in the trials conducted at a European center. Thus, the cost effectiveness in Korea must be analyzed based on the medical circumstances there. In Korean medical circumstances, the predominant factor associated with the lower total sum of costs for OSR was the cost of the procedures themselves. The operation-related fee in Korea is lower than that in Western countries, while the costs of endovascular devices are higher in Korea. The Endurant-bifurcated body costed 4.024 USD and the Endurant-contralateral limb costed 2,445 USD in 2019. Moreover, disposables such as balloons, catheters, and guidewires are expensive. Table 7 shows the costs of devices, examinations, and procedures according to the cost in 2019 (exchange rate, 2019 [11]). Primary procedure in-hospital costs of EVAR are much higher than those of OSR (EVAR under GA, $12 478; EVAR under LA, $12 199; OSR, $5467).

This study had several limitations. This retrospective study was conducted in a single center. The patients were able to choose the operation method and procedure; thus, the study was not randomized. Furthermore, although vascular surgeons and radiologists discussed with each other, it is possible that different specialists performed the same procedure may affect the results. However, the study has several strengths, including the fact that we directly collected telephone survey responses for the EQ-5D score after the procedure. We used the average score during the first three years after the primary procedure. This could be a factor for enabling us to measure the QALYs accurately.

In conclusion, the results of this study suggest that the complication rate is lower for OSR, and that OSR shows better cost effectiveness than EVAR in young patients, under the age of 70 years, with a suitable aortic anatomy. Therefore, OSR can be the first choice for surgeons to treat young patients with AAA and appropriate anatomical features.

Supporting information

S1 Table. STROBE checklist.

(DOCX)

S1 File. Studys minimal underlying data.

(XLSX)

Data Availability

All relevant data are within the manuscript and its Supporting Information files.

Funding Statement

The authors received no specific funding for this work.

References

  • 1.JL DB, AF B, Buth J ea, Group DS. Longterm outcome of open or endovascular repair of abdominal aortic aneurysm. N Engl J Med. 2010;362:1881–9. doi: 10.1056/NEJMoa0909499 [DOI] [PubMed] [Google Scholar]
  • 2.The United Kingdom EVAR Trial Investigators. Endovascular versus open repair of abdominal aortic aneurysm. N Engl J Med. 2010;362(20):1863–71. Epub 2010/04/13. doi: 10.1056/NEJMoa0909305 . [DOI] [PubMed] [Google Scholar]
  • 3.Patel R, Sweeting MJ, Powell JT, Greenhalgh RM, EVAR Trial Investigators. Endovascular versus open repair of abdominal aortic aneurysm in 15-years’ follow-up of the UK endovascular aneurysm repair trial 1 (EVAR trial 1): a randomised controlled trial. Lancet. 2016;388(10058):2366–74. doi: 10.1016/S0140-6736(16)31135-7 WOS:000387436900025. [DOI] [PubMed] [Google Scholar]
  • 4.Salata K, Hussain MA, de Mestral C, Greco E, Aljabri BA, Mamdani M, et al. Comparison of outcomes in elective endovascular aortic repair vs open surgical repair of abdominal aortic aneurysms. JAMA Netw Open. 2019;2(7):e196578. Epub 2019/07/11. doi: 10.1001/jamanetworkopen.2019.6578 ; PubMed Central PMCID: PMC6624804. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 5.Kim JY, Choi E, Cho YP, Han Y, Kwon TW. Fate of Pure Type II Endoleaks Following Endovascular Aneurysm Repair. Vasc Specialist Int. 2019;35(3):129–36. Epub 2019/10/18. doi: 10.5758/vsi.2019.35.3.129 ; PubMed Central PMCID: PMC6774429. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 6.NICE. Stent-graft placement in abdominal aortic aneurysm: Interventional procedures guidance [IPG163] 2016 [updated March 22; cited 2020 December 18]. Available from: https://www.nice.org.uk/guidance/ipg163.
  • 7.Moll FL, Powell JT, Fraedrich G, Verzini F, Haulon S, Waltham M, et al. Management of abdominal aortic aneurysms clinical practice guidelines of the European society for vascular surgery. Eur J Vasc Endovasc Surg. 2011;41:S1–S58. Epub 2011/01/11. doi: 10.1016/j.ejvs.2010.09.011 . [DOI] [PubMed] [Google Scholar]
  • 8.Marone EM, Freyrie A, Ruotolo C, Michelagnoli S, Antonello M, Speziale F, et al. Expert Opinion on Hostile Neck Definition in Endovascular Treatment of Abdominal Aortic Aneurysms (a Delphi Consensus). Ann Vasc Surg. 2020;62:173–82. Epub 2019/08/09. doi: 10.1016/j.avsg.2019.05.049 . [DOI] [PubMed] [Google Scholar]
  • 9.Noh M, Choi BM, Kwon H, Han Y, Ko GY, Kwon TW, et al. General anesthesia versus local anesthesia for endovascular aortic aneurysm repair. Medicine (Baltimore). 2018;97(32):e11789. Epub 2018/08/11. doi: 10.1097/MD.0000000000011789 ; PubMed Central PMCID: PMC6133456. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 10.KOSIS. [KOSIS web site]. Daejeon: Statistics Korea; [cited 2020 May 7]. Available from: http://kosis.kr/index/index.do.
  • 11.OECD. Exchange rates (indicator) [Internet]. 2020 [cited 2020 December 18]. Available from: 10.1787/037ed317-en. [DOI]
  • 12.Lee YK, Nam HS, Chuang LH, Kim KY, Yang HK, Kwon IS, et al. South Korean time trade-off values for EQ-5D health states: modeling with observed values for 101 health states. Value Health. 2009;12(8):1187–93. Epub 2009/08/08. doi: 10.1111/j.1524-4733.2009.00579.x . [DOI] [PubMed] [Google Scholar]
  • 13.Prinssen M, Buskens E, Blankensteijn JD, Dream trial participants. Quality of life endovascular and open AAA repair. Results of a randomised trial. Eur J Vasc Endovasc Surg. 2004;27(2):121–7. Epub 2004/01/14. doi: 10.1016/j.ejvs.2003.11.006 . [DOI] [PubMed] [Google Scholar]
  • 14.Canning P, Tawfick W, Whelan N, Hynes N, Sultan S. Cost-effectiveness analysis of endovascular versus open repair of abdominal aortic aneurysm in a high-volume center. J Vasc Surg. 2019;70(2):485–96. Epub 2019/02/20. doi: 10.1016/j.jvs.2018.11.018 . [DOI] [PubMed] [Google Scholar]
  • 15.IMPROVE Trial Investigators. Comparative clinical effectiveness and cost effectiveness of endovascular strategy v open repair for ruptured abdominal aortic aneurysm: three year results of the IMPROVE randomised trial. BMJ. 2017;359:j4859. Epub 2017/11/16. doi: 10.1136/bmj.j4859 ; PubMed Central PMCID: PMC5682594 at www.icmje.org/coi_disclosure.pdf and declare: no support from any organisation for the submitted work;no financial relationships with any organisations that might have an interest in the submitted work in the previous three years; no other relationships or activities that could appear to have influenced the submitted work. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 16.Lilja F, Mani K, Wanhainen A. Editor’s Choice—Trend-break in Abdominal Aortic Aneurysm Repair With Decreasing Surgical Workload. Eur J Vasc Endovasc Surg. 2017;53(6):811–9. Epub 2017/04/11. doi: 10.1016/j.ejvs.2017.02.031 . [DOI] [PubMed] [Google Scholar]
  • 17.Becquemin JP. The ACE trial: a randomized comparison of open versus endovascular repair in good risk patients with abdominal aortic aneurysm. J Vasc Surg. 2009;50(1):222–4; discussion 4. Epub 2009/07/01. doi: 10.1016/j.jvs.2009.04.074 . [DOI] [PubMed] [Google Scholar]
  • 18.Lederle FA, Freischlag JA, Kyriakides TC, Matsumura JS, Padberg FT Jr., Kohler TR, et al. Long-term comparison of endovascular and open repair of abdominal aortic aneurysm. N Engl J Med. 2012;367(21):1988–97. Epub 2012/11/23. doi: 10.1056/NEJMoa1207481 . [DOI] [PubMed] [Google Scholar]
  • 19.Chang RW, Goodney P, Tucker LY, Okuhn S, Hua H, Rhoades A, et al. Ten-year results of endovascular abdominal aortic aneurysm repair from a large multicenter registry. J Vasc Surg. 2013;58(2):324–32. Epub 2013/05/21. doi: 10.1016/j.jvs.2013.01.051 ; PubMed Central PMCID: PMC3930460. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 20.Antoniou GA, Antoniou SA, Torella F. Editor’s Choice—Endovascular vs. Open Repair for Abdominal Aortic Aneurysm: Systematic Review and Meta-analysis of Updated Peri-operative and Long Term Data of Randomised Controlled Trials. Eur J Vasc Endovasc Surg. 2020;59(3):385–97. Epub 2020/01/04. doi: 10.1016/j.ejvs.2019.11.030 . [DOI] [PubMed] [Google Scholar]
  • 21.Sirignano P, Speziale F, Montelione N, Pranteda C, Galzerano G, Mansour W, et al. Abdominal Aortic Aneurysm Repair: Results from a Series of Young Patients. Biomed Res Int. 2016;2016:7893413. Epub 2016/10/26. doi: 10.1155/2016/7893413 ; PubMed Central PMCID: PMC5061946. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 22.Gallitto E, Faggioli G, Mascoli C, Pini R, Spath P, Gabellini T, et al. Long-term EVAR efficacy in young patients. Eur J Vasc Endovasc Surg. 2019;58:E297. doi: 10.1016/j.ejvs.2019.06.904 [DOI] [Google Scholar]
  • 23.The United Kingdom EVAR Trial Investigators. Endovascular repair of arotic aneurysm in patients physicaly ineligible for open repair. N Engl J Med. 2010;362(20):1872–80. doi: 10.1056/NEJMoa0911056 [DOI] [PubMed] [Google Scholar]
  • 24.Choi K, Han Y, Ko GY, Cho YP, Kwon TW. Early and Late Outcomes of Endovascular Aortic Aneurysm Repair versus Open Surgical Repair of an Abdominal Aortic Aneurysm: A Single-Center Study. Ann Vasc Surg. 2018;51:187–91. Epub 2018/05/18. doi: 10.1016/j.avsg.2018.02.042 . [DOI] [PubMed] [Google Scholar]
  • 25.FA L, JA F, TC K, Open Versus Endovascular Repair (OVER) Veterans Affairs Cooperative Study Group. Outcomes following endovascular vs open repair of abdominal aortic aneurysm: a randomized trial. JAMA. 2009;309(302):1535–42. [DOI] [PubMed] [Google Scholar]
  • 26.Brown LC, Powell JT, Thompson SG, Epstein DM, Sculpher MJ, Greenhalgh RM. The UK EndoVascular Aneurysm Repair (EVAR) trials: randomised trials of EVAR versus standard therapy. Health Technol Assess. 2012;16:1–218. doi: 10.3310/hta16090 [DOI] [PubMed] [Google Scholar]
  • 27.Gwon JG, Kwon TW, Cho YP, Han YJ, Noh MS. Analysis of in hospital mortality and long-term survival excluding in hospital mortality after open surgical repair of ruptured abdominal aortic aneurysm. Ann Surg Treat Res. 2016;91(6):303–8. Epub 2016/12/03. doi: 10.4174/astr.2016.91.6.303 ; PubMed Central PMCID: PMC5128376. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 28.Jeong S, Kwon TW, Han Y, Cho YP. Surgical Repair of Juxtarenal Abdominal Aortic Aneurysms and safety of Suprarenal Aortic Clamping. World J Surg. 2020;44(6):2002–9. Epub 2020/02/06. doi: 10.1007/s00268-020-05409-1 . [DOI] [PubMed] [Google Scholar]
  • 29.Burgers LT, Vahl AC, Severens JL, Wiersema AM, Cuypers PW, Verhagen HJ, et al. Cost-effectiveness of Elective Endovascular Aneurysm Repair Versus Open Surgical Repair of Abdominal Aortic Aneurysms. Eur J Vasc Endovasc Surg. 2016;52(1):29–40. Epub 2016/04/28. doi: 10.1016/j.ejvs.2016.03.001 . [DOI] [PubMed] [Google Scholar]
  • 30.Epstein D, Sculpher MJ, Powell JT, Thompson SG, Brown LC, Greenhalgh RM. Long-term cost-effectiveness analysis of endovascular versus open repair for abdominal aortic aneurysm based on four randomized clinical trials. Br J Surg. 2014;101(6):623–31. Epub 2014/03/26. doi: 10.1002/bjs.9464 . [DOI] [PubMed] [Google Scholar]

Decision Letter 0

Robert Jeenchen Chen

12 Aug 2021

PONE-D-21-24097

Comparison of the quality of life and cost-effectiveness of endovascular versus open surgical repair for abdominal aortic aneurysm in young patients

PLOS ONE

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Reviewer #1: First of all, congratulate the authors for the idea and the work presented. There are some controversial aspects about the advantages of one technique or another in certain groups of patients and the results of the treatment in a short, medium and long term.

Next, a series of recommendations are made to the authors for their consideration.

Why did they choose that period of time for patient inclusion and on which they based the period of time necessary for patient follow-up?

Line 165 statistical analysis It is important that the authors indicate how the sample size was calculated or, failing that, with the analyzed sample, how we can be sure that the data is statistically significant and relevant?

Authors should explain what the operator's experience was, and what it depended on being performed by a radiologist or vascular surgeon.

line 67 please include the reference.

Please define what you understand by high anesthetic risk and how you estimated the risk of each patient.

It would be important for the authors to include the cause of the aneurysm (aetiology), that is, if it is of atherosclerotic origin related to hypertension or is it due to an arteriopathy.

Were any criteria used for the EVAR to be performed by radiologists or vascular surgeons?

Line 136 outcomes. It would be very interesting to know data from both groups such as mortality, complications in the immediate postoperative period or the length of hospital stay.

Line 155 the authors do not have to describe what the EQ-5D is. It would be important that the authors indicate how often and when the questionnaire was passed to the patients. It is to be expected that at some moments of the follow-up there would be differences between the groups.

Table 3 is misleading in interpretation. When the 1st complication including reoperation is indicated, really in the OSR group no patient required reoperation due to the pathology. Redo the statistical analysis removing these three patients from the study.

Table 4 also leads to false interpretation. The average cost of the process is indicated. Include the total cost of complications in each of the groups.

Table 5 please review the data of in-hospital cost EVAR since the cost reported is not included in the cost range

The same happens in table 6.

In the discussion section, the authors include data that are part of the results, for example the mean stays or the long-term survival rate. Please, review it.

The complications that appear in the limitations must be transferred to the results, furthermore this is not a limitation, if it could be the sample size but not the appearance of these complications.

Consider including in the limitations the form of inclusion of patients in each of the two branches of the study. In addition, it can also be a limitation not knowing what caused the same procedure to be performed on some occasions by a radiologist and on others by a surgeon. Another limitation of the study is the cost analysis, the authors do not individually consider the cost of staff (surgeons, radiologists, nurses)

PRISMA checklist should be added as supplemental table.

Please, review reference 1.

Reviewer #2: - Purpose: To evaluate quality of life and cost-effectiveness up to a 3-years FU between EVAR and OSR in patients under 70-y-o with a surgical aneurysm of abdominal aorta. The authors base their analysis on QALY which stands for “Quality Adjusted Life Year”. The QALY is commonly used in health economic evaluations as a means of quantifying the health effect of a medical intervention or a prevention program and ultimately to help payers allocate healthcare resources. It is however rather imprecise to determine the true QOL for which specific scales are proposed (but not used in the present study). I therefore recommend that the title of the manuscript would be changed accordingly: “Quality Adjusted Life Year comparison at medium term follow-up….”

- Methods: Retrospective study including 90 patients <70-y-o for whom aortic morphology would have allowed to perform TEVAR and who underwent TEVAR (37) or OSR (53) between January 2012 and October 2016.

• It is well known that studies which retrospectively screen if certain patients would have been eligible for one interventional treatment rather than for another one are flawed by many biases. Among those biases are the technological evolution of imaging, materials, and indications as well as the improvement of the individual experience and global quality of care. Those biases tend to render rather futile any comparison of patient populations treated at different time and to invalid in a more recent patient population some general results found in an historical study. For instance to compare patients who, very restrictively, benefited from TAVR between 2012 and 2016 which those who are liberally treated nowadays with TAVR updated prostheses does not make much sense. Even worse if we consider studying patients who “might have benefited from TAVR between 2012 and 2016”. To deal with such biases in the current study the authors chose to select only patients who met the nowadays aortic morphology criteria for EVAR and retrospectively reviewed all preoperative CT.

- It is important to precise who is behind the “we analysed” preoperative CT. Was it the same observer for all CT? Were results double checked? Was a certified radiologist present among authors? Which imaging software was used?

- It is crucial therefore that the authors make it clear in “Methods” that not a single patient from the (historical) EVAR group did not meet the nowadays aortic morphology criteria for EVAR because this might significantly increase the risk of impaired outcomes during follow-up.

• On the other hand, to avoid including patients that might have not tolerate OSR, the authors have excluded 14 patients for EVAR who would not have tolerate general anaesthesia. However the EVAR group did include 18 procedures (50%) performed under local anaesthesia. The authors must therefore precise the criteria of choice for local versus general anaesthesia in the EVAR group and how they can retrospectively be sure that patients who underwent EVAR under LA could have tolerate GA as well?

- Results: Even in case of a favourable anatomy, a lesser invasive treatment tend to be proposed in frail or disable patients. Patients with a past history of cancer are also good candidate for a lesser invasive treatment. The authors present a baseline comparison of demographics (Table 1) which is in line with this general figure. Due to the low number of patients and to assess a better comparison between both groups (taking into account that this is not a matched study), I strongly recommend that the authors present in Table 1 the Charlson Comorbidity Index for EAVR and OSR patients.

• A higher rate of complications is expected with EVAR during follow-up and patients must stay therefore under imaging surveillance for a life time which impacts QOL. Some large recent randomised trials share those unequivocal conclusions, however a lower global survival with EVAR in the long term is not unanimously found (please do actualise bibliography, for instance we expect to find DOI: 10.1056/NEJMoa1715955). I strongly recommend to present actuarial survival curves (freedom from death of any cause, freedom of death from aortic cause, and freedom of reintervention) in a Figure 1.

• HRQOL (Health Related Quality of Life) is usually assessed by a score on a HRQOL-14 items scale. Since such a scale has not been used, I recommend the authors to strictly stay on the notions of QALY which can be assimilated to the crude survival in complete heath for each group and cost per QALY which are relevant in this study up to a medium term FU.

• Finally minor English revisions are required, please check carefully manuscript (for instance: “Heria repair” in Table 4; “Fallow-up cost” in Table 6; “follow-ups” in Cost analysis…..)

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Reviewer #1: No

Reviewer #2: Yes: Pr. Dr. CAUS Thierry, MD, PhD

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PLoS One. 2021 Dec 2;16(12):e0260690. doi: 10.1371/journal.pone.0260690.r002

Author response to Decision Letter 0


28 Oct 2021

Reviewer 1: We have incorporated all of your suggestions into my revision. They were very helpful. We uploaded our response as an attachment. Thank you for your help.

Reviewer 2: We have incorporated all of your suggestions into my revision. They were very helpful. We uploaded our response as an attachment. Thank you for your help.

Attachment

Submitted filename: Response to Reviewers.docx

Decision Letter 1

Robert Jeenchen Chen

16 Nov 2021

Quality Adjusted Life Year comparison at medium term follow-up of endovascular versus open surgical repair for abdominal aortic aneurysm in young patients

PONE-D-21-24097R1

Dear Dr. Kwon,

We’re pleased to inform you that your manuscript has been judged scientifically suitable for publication and will be formally accepted for publication once it meets all outstanding technical requirements.

Within one week, you’ll receive an e-mail detailing the required amendments. When these have been addressed, you’ll receive a formal acceptance letter and your manuscript will be scheduled for publication.

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Kind regards,

Robert Jeenchen Chen, MD, MPH

Academic Editor

PLOS ONE

Additional Editor Comments (optional):

Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. If the authors have adequately addressed your comments raised in a previous round of review and you feel that this manuscript is now acceptable for publication, you may indicate that here to bypass the “Comments to the Author” section, enter your conflict of interest statement in the “Confidential to Editor” section, and submit your "Accept" recommendation.

Reviewer #1: All comments have been addressed

Reviewer #3: All comments have been addressed

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2. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer #1: Yes

Reviewer #3: Yes

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3. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #1: Yes

Reviewer #3: Yes

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4. Have the authors made all data underlying the findings in their manuscript fully available?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.

Reviewer #1: Yes

Reviewer #3: Yes

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5. Is the manuscript presented in an intelligible fashion and written in standard English?

PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.

Reviewer #1: Yes

Reviewer #3: Yes

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6. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #1: Congratulate the authors for the revision work they have done.

I think the final version has improved a lot.

Reviewer #3: (No Response)

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Reviewer #1: Yes: Juan Bustamante-Munguira MD PhD MsC MPH Head Cardiac Surgery Department. University Hospital of Valladolid. Spain.

Reviewer #3: No

Acceptance letter

Robert Jeenchen Chen

23 Nov 2021

PONE-D-21-24097R1

Quality Adjusted Life Year comparison at medium term follow-up of endovascular versus open surgical repair for abdominal aortic aneurysm in young patients

Dear Dr. Kwon:

I'm pleased to inform you that your manuscript has been deemed suitable for publication in PLOS ONE. Congratulations! Your manuscript is now with our production department.

If your institution or institutions have a press office, please let them know about your upcoming paper now to help maximize its impact. If they'll be preparing press materials, please inform our press team within the next 48 hours. Your manuscript will remain under strict press embargo until 2 pm Eastern Time on the date of publication. For more information please contact onepress@plos.org.

If we can help with anything else, please email us at plosone@plos.org.

Thank you for submitting your work to PLOS ONE and supporting open access.

Kind regards,

PLOS ONE Editorial Office Staff

on behalf of

Dr. Robert Jeenchen Chen

Academic Editor

PLOS ONE

Associated Data

    This section collects any data citations, data availability statements, or supplementary materials included in this article.

    Supplementary Materials

    S1 Table. STROBE checklist.

    (DOCX)

    S1 File. Studys minimal underlying data.

    (XLSX)

    Attachment

    Submitted filename: Response to Reviewers.docx

    Data Availability Statement

    All relevant data are within the manuscript and its Supporting Information files.


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