Advanced age is significantly associated with poor outcomes of thoracic endovascular aortic repair: a systematic review and meta-analysis

Abstract

Background

Whether advanced age is a risk factor for poor outcomes of thoracic endovascular aortic repair (TEVAR) remains unclear. This study aimed to evaluate the association between advanced age and outcomes after TEVAR.

Methods

To identify studies regarding TEVAR and age, the PubMed and Web of Science databases were systematically searched in July 2023. The associations between advanced age and outcomes of TEVAR for individuals with any types of thoracic aortic diseases were assessed according to the odds ratio (OR) or hazard ratio (HR). The ages of patients who suffered from adverse events after TEVAR were also compared. Study quality was assessed by using the Newcastle‒Ottawa Scale.

Results

A total of 70 studies with 52,605 patients were included in this meta-analysis. All enrolled studies were considered high-quality. Overall, advanced age was significantly associated with higher risk of postoperative mortality (p < 0.0001) and neurological complications (p = 0.006), especially delirium (p = 0.009), spinal cord ischemia (p = 0.02) and overall neurological complications (p = 0.007). Notably, the age of patients experiencing postoperative stroke was slightly older than those did not (p = 0.05). However, advanced age was not significantly associated with an elevated risk of postoperative overall complications (p = 0.59) or adverse aortic remodeling events (p = 0.34), including aortic dilation (p = 0.43) or false lumen dilation (p = 0.52). Moreover, patients who experienced acute kidney injury after TEVAR were significantly younger than those who did not (p = 0.04).

Conclusion

Advanced age is associated with poor outcomes of TEVAR, including postoperative mortality and neurological complications, though overall complications and aortic remodeling outcomes are similar. Additionally, AKI was even more frequent in younger patients. It is important to evaluate risk and benefit before deciding to perform TEVAR on older patients. Optimized peri-operative management should be developed and provided for older patients.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12893-025-02990-x.

Introduction

Older individuals are the fastest growing population in the world’s largest economies, such as the USA, China, Japan, Germany and the UK. For instance, the number of individuals aged 65 and older is predicted to exceed the number of children in the USA by 2034 (77 vs. 76.5 million) [1]. It has become more common for people to live into their 9th decade due to the development of modern medicine and preventative care [2]. However, the rapid rise in the population aged 80 and above leads to continued growth in the number of patients with aortic lesions and cardiovascular disease [3–5].

Descending thoracic aortic aneurysms (DTAA) and type B aortic dissection (TBAD) are rare but fatal cardiovascular conditions. Specifically, most DTAA patients appear to be asymptomatic until fatal events occur [6]. Over the past two decades, thoracic aortic pathology has been widely managed by thoracic endovascular aortic repair (TEVAR) [7, 8]including DTAA and TBAD, due to its minimally invasive nature compared to conventional open surgery [9, 10]. Additionally, EVAR has many advantages over conventional open surgery, such as reduced internal organ ischemia, reduced blood loss, reduced paraplegia risk, prevention of aortic cross-clamping and shorter hospital stay [11–13]. Currently, penetrating aortic ulcers [14]ruptured thoracic aortic aneurysms [15]and traumatic aortic injuries [16] are also recommended to be treated by TEVAR. The success rate of TEVAR is now approximately 98%, with a lower risk of postoperative complications and mortality than that of open surgery [17].

Unfortunately, after TEVAR, patients may suffer from stroke, paraplegia, acute kidney injury (AKI), peripheral vascular complications, infections, cardiac complications, and even death. Advanced age is commonly considered a risk factor for adverse events after surgery. Although several studies report the outcomes of TEVAR in older individuals [6, 18–20] whether advanced age is a risk factor for poor outcomes of TEVAR remains unclear. Therefore, we conducted this systematic review and meta-analysis to evaluate the association between advanced age and outcomes after TEVAR, focusing on postoperative mortality, general complications, acute kidney injury (AKI), adverse aortic remodeling events and neurological complications.

Materials and methods

Search strategy

The protocol for this systematic review was developed prospectively and registered in PROSPERO (CRD42023438243). This systematic review was conducted following the Preferred Reporting Items for MOOSE and PRISMA recommendations [21, 22]. A comprehensive online literature search using the following search terms was performed: PubMed, Web of Science and Scopus. The search query was as follows: “Thoracic endovascular aortic repair” AND age. The article search was performed in July 2023.

Selection of eligible studies

The inclusion criteria included the following: (1) cohort studies reporting the association between advanced age and outcomes of TEVAR for thoracic aortic diseases, including DTAA and TBAD; (2) studies with valid data, which were described in “Data acquisition and quality assessment”; (3) adult studies; (4) studies published in English; and (5) original reports with ≥ 10 patients.

Review papers, letters, preclinical studies commentary, or editorials were excluded. Studies including patients who received medical treatment, underwent open surgery, or had type A aortic dissection, abdominal aortic diseases or aortic sinus fistula were excluded. Duplicate studies with overlapping data were also excluded.

Two review authors screened the search results, first in title and abstract and then in full text.

Data extraction was conducted by two independent reviewers. Sample size, age, sex and types of aortic diseases were collected as baseline data.

To evaluate the association between advanced age and the outcome of TEVAR, the following data were extracted: (1) ORs or HRs with corresponding 95% CIs; (2) mean with standard deviation of age; and (3) incidence of outcome events after TEVAR.

The quality of enrolled cohort studies was assessed using the Newcastle–Ottawa Quality Assessment Scale (NOS) [23]. Studies based on prospectively collected multicenter Vascular Quality Initiative (VQI) registry data were considered prospective cohort studies.

Outcomes

The primary outcome was mortality following TEVAR. The secondary endpoints included the following postoperative complications: (1) overall adverse events; (2) adverse aortic remodeling events, including aortic dilation and false lumen (FL) dilation; (3) acute kidney injury (AKI); and (4) neurological complications, including stroke, spinal cord ischemia, delirium and overall neurological complications. Overall aortic-related events were considered overall adverse events.

Data analysis

Review Manager Software version 5.4.1 was used to calculate the pooled effect. A random-effects model and fixed-effects model were adopted to obtain the pooled MDs and 95% confidence intervals (CIs). Heterogeneity was tested by using the chi-squared test and I [2] statistic. p < 0.05 or I² > 50% indicated that the heterogeneity was significant, in which case the random-effects model was applied. The overall effects were determined by the Z test, and a p value < 0.05 was considered statistically significant. Subgroup analysis was conducted according to specific age group or adverse events. The incidence of outcome events after TEVAR was used to calculate the relevant OR and 95% CI.

Assessments of possible biases

Stata17 was used to conduct sensitivity analysis to assess the role of the diagnostic threshold, subgroup criteria, study population characteristics or surgery type in the final pooled results. Funnel plots were applied to examine the potential publication bias for comparisons that included more than 10 studies.

Results

Search result

Database searches identified 6595 references (PubMed: 810; Web of Science: 5785). After automatic deduplication by using EndNote 20, the titles and abstracts of 5772 references were subsequently screened. The full texts of 290 articles were screened. 220 were excluded for several reasons (Fig. 1). Ultimately, 70 studies were included in the meta-analysis with 52,605 patients enrolled [6, 18, 24–91].

Fig. 1.

Preferred reporting items for systemic reviews and meta-analysis flow diagram of literature screening

General characteristics of the included studies

The general characteristics of the included studies are presented in Table 1, including the first author, year of publication, study design and baseline patient characteristics. All patients included in this study suffered from thoracic aortic pathology that was treated with the TEVAR procedure. Among the 70 cohort studies, 14 were prospective, and the rest were retrospective studies. According to NOS, all cohort studies were classified as high quality (Supplementary Table 1).

Table 1.

Baseline characteristics of enrolled studies

Author	Year	Area	Diseases	Study Design	Sample Size	Age	Male	Quality Scorea	Outcome
Michele Gallo	2023	Switzerland	-	retrospective	116	63.7 ± 18.0	88	7	mortality
Shuangjing Wang	2023	China	complicated TBAD	retrospective	170	51.5 (42.3–61.0)	147	7	overall complications
Yufei Zhao	2023	China	TBAD	retrospective	186	58.5 ± 10.3	149	7	overall complications
Ali Mohammad Haji-Zeinali	2023	Iran	-	retrospective	123	56.7 ± 15	102	7	mortality
John R Spratt	2023	Fla	-	prospective	869	67.1 ± 13.7	658	7	neurological complications
Zhankui Du	2022	China	ATBAD	retrospective	479	53.35 ± 11.27	392	7	mortality
Yufei Zhao	2022	China	TBAD	retrospective	201	59.11 ± 12.46	162	7	overall complications
Wanbing Huang	2022	China	TBAD	retrospective	434	57.5 ± 11.3	385	7	neurological complications
Giacomo Murana	2022	Italy	penetrating atherosclerotic ulcer	retrospective	73	72.0 ± 8.1	58	7	mortality
Zhengbiao Zha	2022	China	TBAD	retrospective	445	53.0 ± 3.2	240	7	neurological complications
Xiuping An	2021	China	TBAD combined with renal artery involvement	retrospective	256	52.8 ± 9.8	217	7	acute kidney injury
Khaled I Alnahhal	2022	USA	rTAA, intact TAA, TBAD	retrospective	4108	≥ 80 years (n = 676)	2465	7	mortality
Miriam Rychla	2022	Switzerland	ATBAD	retrospective	57	69.0 (59.6–78.2)	42	7	overall complications
Isaac N Naazie	2022	USA	TAA	prospective	2141	72.3 ± 10.5	1147	7	mortality
Patricia Yau	2021	USA	-	retrospective	30	68.5 ± 11.7	15	7	adverse aortic remodeling events
Hanaa Dakour-Aridi	2021	USA	-	prospective	2042	-	1181	7	overall complications, neurological complications
Yoshimasa Seike	2021	Japan	TAA	retrospective	136	76 ± 7.4	107	7	neurological complications
Vy T Ho	2021	USA	blunt thoracic aortic injury	prospective	655	41.8 ± 17.4	479	7	mortality
Grace J Wang	2021	USA	TBAD	prospective	2820	60.1 ± 12.5	1985	7	mortality
Zhichun Gao	2020	China	ATBAD	retrospective	391	57.1 ± 12.0	311	7	mortality
Hiroshi Banno	2021	Japan	-	retrospective	212	76.1 ± 4.9	170	7	neurological complications
Vy T Ho	2021	USA	-	retrospective	3095	74.4 ± 9.3	1716	7	mortality
Kirthi S Bellamkonda	2021	USA	-	retrospective	3281	-	1886	7	mortality
Adam Tanious	2021	USA	TAA	retrospective	219	74 ± 10.5	120	7	mortality
Abdul Q Alarhayem	2021	USA	BTAI	retrospective	3042	42.4 ± 20.2	2140	7	mortality
Chiara Lomazzi	2020	Italy	-	retrospective	887	65 ± 14	592	7	overall complications
Jong Hyun Choi	2021	Korea	rTAD	retrospective	37	67.1 ± 15.3	23	7	overall complications
Xue-Biao Wei	2020	China	sub-ATBAD	retrospective	605	54.7 ± 10.8	520	7	mortality
Elizabeth L Norton	2020	USA	ATBAD	retrospective	182	55 (48–65)	139	8	mortality
Ryan W King	2020	USA	-	prospective	4010	63.0 ± 15.6	2424	8	mortality
Sari Hammo	2019	Sweden	rTAA	retrospective	140	74.07 ± 8.8	79	8	mortality
Hongwei Yang	2019	China	TBAD	retrospective	671	54.6 ± 10.8	580	7	mortality
Karl Sörelius	2019	Sweden	mycotic TAA	retrospective	52	71.3 ± 8.1	28	7	mortality
Akihiro Hosaka	2019	Japan	-	retrospective	77	78 (72–81)	63	7	mortality
Nikolaos Tsilimparis	2018	Germany	-	retrospective	521	67.2 ± 15	349	7	mortality
Eric E Roselli	2018	USA	-	retrospective	39	-	23	8	mortality
Yoshimasa Seike	2018	Japan	-	retrospective	215	83.4 ± 3.0	92	8	mortality
Seungjun Song	2017	South Korea	-	prospective	162	60.6 ± 12.5	57	8	neurological complications
Frances Y Hu	2017	USA	-	prospective	826	68.2 ± 12.7	473	9	mortality
Alessandro Gasparetto	2017	USA	TBAD	retrospective	62	57.6 ± 6.6	45	7	adverse aortic remodeling events
Arnoud V Kamman	2017	Italy	uncomplicated TBAD	prospective	21	57.6 ± 14.0	18	7	adverse aortic remodeling events
Yun-Ho Jeon	2016	Korea	-	retrospective	57	61.2 ± 17.5	46	7	acute kidney injury
D Böckler	2016	Germany	-	retrospective	100	65 ± 1.41	65	8	mortality
Rolf Alexander Jánosi	2016	Germany	-	retrospective	63	69.1 ± 11.5	40	7	mortality
Tim Buckenham	2015	New Zealand	-	retrospective	264	60.8 ± 17.8	175	7	mortality, neurological complications
Tae-Hoon Kim	2014	Korea	TBAD	retrospective	38	60 ± 12	25	8	adverse aortic remodeling events
Salvatore T Scali	2014	USA	-	retrospective	741	65.6 ± 14.8	530	8	neurological complications
Yoshiki Watanabe	2014	Japan	-	retrospective	52	59.7 ± 13.3	41	7	overall complications
Chikara Ueki	2014	USA	TBAD	retrospective	228	70.4 ± 11.8	153	7	mortality
Dominik Wiedemann	2013	USA	TAA, TBAD, perforating aortic ulcer, traumatic aortic transections	retrospective	300	median67 (range 20–88)	220	8	mortality
Arin L Madenci	2013	USA	-	retrospective	877	66.0 (57.0–74.0)	430	7	overall complications
Kate P Zimmerman	2016	USA	-	retrospective	1417	63.3 ± 13.5	901	9	mortality
Drosos Kotelis	2012	Germany	-	prospective	300	median66 (range 21–89)	205	7	neurological complications
Brant W Ullery	2012	USA	-	retrospective	530	71.3 ± 12.0	315	8	neurological complications
Salvatore T Scali	2012	USA	TAA	prospective	224	60.6 ± 0.5	140	7	mortality
Gabriele Piffaretti	2012	Italy	-	retrospective	171	69 ± 14	137	7	acute kidney injury
Richard P Cambria	2009	USA	-	prospective	59	62.2 ± 19.3	-	8	mortality
Massimiliano M Marrocco-Trischitta	2009	Italy	-	retrospective	179	-	150	8	mortality
Holger Eggebrecht	2008	Germany	-	retrospective	103	64.5 ± 11.2	70	8	mortality
W Anthony Lee	2011	USA	-	prospective	400	65 ± 16	276	8	mortality
Brant W Ullery	2011	USA	degenerative TAA, TBAD	retrospective	424	70.6 ± 12.0	97	7	neurological complications
Frederik H W Jonker	2011	USA	rTAA	retrospective	92	69.4 ± 11	62	8	mortality, neurological complications
Martin Czerny	2010	Switzerland	-	retrospective	226	Median67	163	7	mortality
H Ohtake	2010	Japan	TAA, TBAD	retrospective	66	70.8 ± 9.2	50	7	neurological complications
Jayer Chung	2010	USA	-	retrospective	252	68.1 ± 11.8	149	7	mortality
Martin Czerny	2011	Switzerland	-	retrospective	286	Median69	203	9	mortality
Marc E Mitchell	2011	USA	-	retrospective	15	52.4 ± 22.5	10	7	mortality
Ruojia Debbie Li	2022	USA	TAA	prospective	3072	Median73	1683	7	neurological complications
Albeir Y Mousa	2020	USA	-	retrospective	7889	67.6 ± 13.9	5125	7	neurological complications

^a Study quality was assessed by Newcastle–Ottawa Quality Assessment Scale

TAA = thoracic aortic aneurysm; TBAD = type B aortic dissection; ATBAD = acute type B aortic dissection; rTAA = ruptured thoracic aortic aneurysm; rTAD = ruptured thoracic aortic disease;

Associations between advanced age and incidence of mortality after TEVAR

Fourteen articles [18, 25, 28, 30, 32, 41, 46, 50, 52, 63, 66, 68, 71, 84] reported the OR of postoperative mortality and advanced age (Fig. 2A). Subgroup analysis was conducted according to different classifications of advanced age. Overall, advanced age was significantly associated with a higher risk of postoperative mortality (OR = 1.34 [95% CI 1.21–1.48], p < 0.00001), regardless of whether 80 years old (OR = 1.54 [95% CI 1.14–2.09], p = 0.005), 75 years old (OR = 2.44 [95% CI 1.73–3.44], p < 0.00001) or 65 years old (OR = 5.60 [95% CI 4.00–7.84], p < 0.00001) was used as the threshold criterion of advanced age. Significant heterogeneity was observed among the studies. Publication bias was assessed by using a funnel plot (supplementary Fig. 1), which indicated moderate publication bias.

Fig. 2.

Forest plot of advanced age on the risk of postoperative mortality. (A) Odds ratio; (B) hazard ratio; (C) mean age

Twenty-one [26, 27, 33, 38, 44, 47, 55–61, 67, 74, 76, 77, 80, 83, 88, 89] studies reported the HR of postoperative mortality and advanced age (Fig. 2B). Similarly, advanced age was significantly associated with a higher risk of postoperative mortality (HR = 1.05 [95% CI 1.03–1.06], p < 0.00001), regardless of whether 80 years old (HR = 4.95 [95% CI 2.45–10.00], p < 0.00001), 75 years old (HR = 6.60 [95% CI 2.12–20.55], p = 0.001), 65 years old (HR = 2.06 [95% CI 1.12–3.79], p = 0.02) or 60 years old (HR = 14.76 [95% CI 2.96–73.50], p = 0.001) was used as the threshold criterion for advanced age. The heterogeneity was significant among studies. Publication bias was assessed by a funnel plot (supplementary Fig. 2), which indicated moderate publication bias.

Seven studies [24, 27, 34, 48, 62, 73, 84] compared the mean age of patients who suffered from postoperative mortality or not. Overall, patients who died after TEVAR were significantly older than those who survived (pooled MD, 6.91; 95% CI, 3.53–10.29, p < 0.0001; Fig. 2C). The heterogeneity was significant among studies.

Association between advanced age and incidence of overall complications after TEVAR

Five studies [6, 40, 64, 90, 91] reported the OR of overall postoperative complications and advanced age (Fig. 3A). Advanced age was not significantly associated with an elevated risk of postoperative overall complications (OR = 1.03 [95% CI 0.93–1.14], p = 0.59). The heterogeneity was significant among studies.

Fig. 3.

Forest plot of advanced age on the risk of postoperative overall complications. (A) Odds ratio; (B) Hazard ratio

Five studies [45, 72, 85, 87, 91] reported the HR of overall postoperative complications and advanced age (Fig. 3B). Advanced age was not significantly associated with an elevated risk of postoperative overall complications (HR = 1.04 [95% CI 0.99–1.09], p = 0.13). The heterogeneity was significant among studies.

Association between advanced age and incidence of AKI after TEVAR

Three studies [37, 49, 69] compared the mean age of patients who did or did not experience postoperative AKI. Overall, patients who experienced AKI after TEVAR were significantly younger than those who survived (pooled MD, -2.96; 95% CI, -5.75–0.16, p = 0.04; Fig. 4). The heterogeneity was insignificant among studies.

Fig. 4.

Forest plot of age in patients suffering from postoperative acute kidney injury or not

Association between advanced age and incidence of adverse aortic remodeling events after TEVAR

Four studies [42, 51, 53, 78] compared the mean age of patients who experienced postoperative adverse aortic remodeling events with those who did not. The difference in age among patients who experienced adverse aortic remodeling events after TEVAR was insignificant (pooled MD, -2.18; 95% CI, -6.66–2.29, p = 0.34; Fig. 5), including aortic dilation (pooled MD, -3.60; 95% CI, -12.46-5.26, p = 0.43) and FL dilation (pooled MD, -1.70; 95% CI, -6.88-3.48 p = 0.52). No significant heterogeneity was observed among the studies.

Fig. 5.

Forest plot of age in patients suffering from postoperative adverse aortic remodeling events or not

Association between advanced age and incidence of neurological complications after TEVAR

Thirteen studies [6, 29, 31, 36, 46, 54, 65, 70, 75, 79, 81, 82, 86] reported the OR of postoperative neurological complications and advanced age (Fig. 6A). Subgroup analysis was conducted according to specific neurological complications, including delirium, stroke and spinal cord ischemia. Overall, advanced age was significantly associated with a higher risk of postoperative neurological complications (OR = 1.10 [95% CI 1.03–1.17], p = 0.004), especially delirium (OR = 2.31 [95% CI 1.23–4.34, p = 0.009), spinal cord ischemia (OR = 1.06 [95% CI 1.01–1.10], p = 0.02) and overall neurological complications (OR = 1.40 [95% CI 1.10–1.78], p = 0.007). Significant heterogeneity was observed among the studies. Publication bias was assessed by a funnel plot, which indicated high publication bias (supplementary Fig. 3).

Fig. 6.

Forest plot of advanced age on the risk of postoperative neurological complications. (A) Odds ratio; (B) mean age

Four studies [35, 39, 43, 65] compared the mean age of patients who did or did not experience postoperative neurological complications. Overall, patients who experienced neurological complications after TEVAR were significantly older than those who did not (pooled MD, 2.83; 95% CI, 1.34–4.32 p = 0.0002; Fig. 6B). Notably, the age of patients who experienced postoperative stroke was marginally higher than that of patients who did not (pooled MD, 4.10; 95% CI, 0.06–8.14, p = 0.05). The heterogeneity was insignificant among studies.

Sensitivity analysis

We conducted a sensitivity analysis on the comparisons with I² > 50%. All relevant results were robust (Fig. 7).

Fig. 7.

The sensitivity analysis of (A) odds ratio of mortality; (B) hazard ratio of death; (C) mean value of death; (D) odds ratio of overall adverse events; (E) hazard ratio of overall adverse events; (F) odds ratio of neurological complications

Discussion

Advanced age is a well-established risk factor for cardiovascular diseases and overall postoperative complications or even mortality. Compared to younger patients, older individuals are at a higher risk due to their reduced physiologic reserve, increased likelihood of comorbidities, and limited life expectancy, advanced age is recognized as a relative contraindication for most surgery, especially for those with a high risk of postoperative complications. However, with the cumulative surgical experience of older patients and prolonged life expectancy, it has become more common for surgeons to perform major cardiovascular surgeries on septuagenarians, octogenarians, and even nonagenarians [92]. Given the increasing need for TEVAR in older patients, we conducted this systematic review and meta-analysis to determine whether advanced age is a risk factor for poor outcomes after TEVAR. In our study, we found that advanced age was associated with a higher risk of postoperative mortality and neurological complications. The differences in the risks of overall postoperative complications and adverse aortic remodeling events among patients of different ages were not significant. Furthermore, patients suffering from postoperative AKI were significantly younger.

It is estimated that older individuals suffer from an average of 8.7 chronic diseases [93, 94]. Multiple comorbidities are associated with worse physical function, increased morbidity, and even higher mortality [93]. Similarly, according to the pooled results, older patients showed a higher postoperative mortality rate. However, in some studies, especially in multivariate regression analysis, age was not a significant predictor of in-hospital mortality, while coronary artery disease, cerebrovascular disease, chronic kidney disease, hypertension, and smoking were strong predictors of mortality [18]. Therefore, advanced age alone is not a deterrent for applying the surgery, and TEVAR may still be an appropriate option for older patients. However, a systematic assessment of frailty, renal function, cardiopulmonary function, and other comorbidities in older patients is crucial [6]. However, that study also found that in ruptured TAA, age was the only risk factor for postoperative mortality. Therefore, screening based on indications for TEVAR in older patients may impact the surgical outcomes, especially in-hospital mortality.

Interestingly, advanced age is not a risk factor for overall postoperative complications according to the pooled results, which may be attributed to selection bias as older patients are often carefully screened for TEVAR based on their risk characteristics. High-risk patients may have been excluded initially, thus not receiving TEVAR [28]. In addition, overall complications encompass a wide range of issues. A study even found that advanced age was a protective factor for poor prognosis in TBAD patients receiving TEVAR [90]. Several studies indicate that young age is a risk factor for extubation failure and longer mechanical ventilation [95–97]. Extubation failure is linked to prolonged stays in intensive care units (ICUs), more complications, and a higher risk of mortality [95, 98]. In addition, the graft composition may contribute to the development of systemic inflammatory response syndrome [99, 100]which can hinder postoperative recovery [101, 102]. Moreover, immunosenescence, which typically occurs in older patients [103]may decrease the risk of developing a postimplantation systemic inflammatory response after TEVAR [104]. Consequently, stent-related inflammation may decline with age, which makes older patients more likely to recover after tent implantation than younger patients. These abovementioned factors may contribute to the decreased risk of some complications in older patients. Future studies should focus on the relationship between the status of the immune system and postoperative complications in older patients.

Similarly, the difference in the mean age of patients suffering from postoperative adverse aortic remodeling events, including aortic dilation and FL dilation, was also insignificant. The principle of TEVAR is to cover the primary entry tear or aneurysm with a stent graft, which subsequently results in thrombosis and a volume reduction in the FL or aneurysm. Thrombosis and negative FL remodeling with increased true lumen volume are key characteristics of successful TEVAR [105, 106]. Adverse aortic remodeling events are relatively common complications after TEVAR. In fact, the diameter of the native aorta gradually increases with age. It has been reported that the aortic diameter in octagenarians is 1 cm larger than that in teenagers. In patients who receive TEVAR, the radial force caused by the graft will make the covered aorta segment dilate at a faster rate, which is influenced by the balance between the recoil force of the aorta and the radial force of the endograft. The dilatation rate may also accelerate over time because of endoleaks resulting from aortic dilatation itself [78]. It has been reported that the preoperative FL area is an independent risk factor for postoperative FL dilation [42]. Increased arterial stiffness associated with advanced age may not significantly contribute to the adverse aortic remodeling events.

However, advanced age is still a risk factor for postoperative neurological complications, including delirium, SCI and overall neurological complications. Neurological complications are a series of fearful complications after TEVAR and, importantly, are not rare. It has been reported that approximately 2–15% of patients experience SCI after TEVAR, leading to serious long-term disability and increased 1-year mortality risk [107–111]. Several hemodynamic factors are believed to be associated with increased SCI risk, such as reduced oxygen carrying capacity from anemia, decreased cardiac index, and arterial hypotension [112, 113]. Hypertension patients may require higher basal mean arterial pressure for maintaining postoperative cord perfusion [114]. Unfortunately, older patients are more likely to have multiple comorbidities, which may increase SCI risk. In addition, older patients may also have some unknown biological vulnerabilities that are associated with underappreciated comorbidity severity, postoperative derangement in cardiac performance indices, and/or unassessed local or systemic changes in spinal cord metabolism [43]. Some strategies have been developed to decrease SCI risk, such as maintaining increased mean arterial pressure and cerebrospinal fluid drainage [115–118]. It is of great importance to identify older patients with a high risk of SCI and provide appropriate preventive measures. Delirium is also reported to occur in more than 10% of patients undergoing TEVAR, leading to longer hospital and ICU stays, as well as higher hospital costs and mortality [119, 120]. In particular, age ≥ 65 years is considered an important risk factor for postoperative delirium by guidelines [121]. Notably, early applied multifactorial nonpharmacologic interventions for patients with a high risk of postoperative delirium can reduce the relevant risk by 44% [122]. Therefore, careful identification of risk factors for postoperative delirium is essential [81].

Regarding AKI, which is also a common and serious complication after TEVAR, we found that patients suffering from AKI after TEVAR were younger than those who did not. AKI is also associated with a longer hospital stay and higher mortality risk [123]. AKI may progress to chronic kidney disease or end-stage renal disease when not diagnosed and managed promptly, leading to substantial medical and financial burdens on patients, families, and society [124, 125]. Elevated blood pressure and long-term hypertension status are closely associated with AKI [126, 127]. Hypertension in young and middle-aged people is often overlooked and poorly controlled, and they also work or live in stressful environments with unhealthy lifestyles. Therefore, younger patients are at higher risk for AKI [128]. One study also found that diastolic blood pressure on admission was closely associated with in-hospital AKI, possibly due to isolated diastolic hypertension in young and middle-aged patients [69].

Perspective of clinical applications and future studies

According to the results of our study, it is important to evaluate risks and benefits before deciding to perform TEVAR on older patients with aortic disease by comprehensively assessing the risk factors for these patients. Optimized perioperative management should be developed and provided for older patients. Our study only focused on the associations between advanced age and outcomes of TEVAR. During the screening of articles, we found that some studies compared TEVAR with medical treatment or open surgery for older patients. Researchers should summarize relevant evidence to determine the appropriate treatment modalities for older patients. Specifically, future studies should investigate the optimal management strategy for older patients with different characteristics.

Limitations

Some limitations of the current study should be noted. First, because of different patient selection criteria and baseline characteristics, such as age, sex and aortic diseases, significant heterogeneity was observed in our meta-analysis. Second, the classification threshold for advanced age and follow-up duration varied among the included studies. The majority of enrolled studies didn’t delineate the cutoff value for defining advanced age. This lack of clarity was particularly evident in studies reporting postoperative complications. Therefore, we didn’t specify what is used as advanced age in the meta-analysis regarding postoperative complications, which may bring bias. Third, our meta-analysis only focused on postoperative mortality, overall complications, adverse aortic remodeling, AKI and neurological complications. Data regarding other complications, such as infection, heart attack and endoleak, were excluded due to the limited number of relevant studies or invalid data. Forth, patients with acute TBAD, patients with chronic TBAD, patients with uncomplicated TBAD, and even blunt aortic injury were enrolled, so that the included population was severely heterogeneous. Moreover, the majority of the included studies neither restricted their scope to specific types of thoracic aortic diseases nor performed independent subgroup analyses stratified by particular disease subtypes, consequently precluding the feasibility of conducting sensitivity analyses targeted at specific categories of thoracic aortic diseases. Fifth, we didn’t adjust comorbidities in meta-analysis due to the lack of relevant data. Finally, although NOS is a commonly used scale for the quality assessment for observational studies, it is a very basic scale and does not include all possible biases. Therefore, the potential bias of enrolled studies may not be fully assessed. Several modalities were employed to reduce these limitations. First, we conducted a systematic, comprehensive search in two databases. Second, we strictly stipulated the inclusion criteria, eliminating the bias caused by some potential confounding factors, and the data were independently extracted by two reviewers. Third, we conducted a subgroup analysis of different age groups or specific neurological complications. Fourth, we conducted a sensitivity analysis to confirm the robustness of the pooled results.

Conclusion

Advanced age is associated with poor outcomes of TEVAR, including postoperative mortality and neurological complications, although overall complications and aortic remodeling outcomes are similar. Additionally, AKI was even more frequent in younger patients. It is crucial to evaluate risks and benefits before deciding to perform TEVAR on older patients. Optimized peri-operative management should be developed and provided for older patients.

Electronic supplementary material

Below is the link to the electronic supplementary material.

Abbreviations

TEVAR

Thoracic endovascular aortic repair

DTAA

Descending thoracic aortic aneurysms

TBAD

Type B aortic dissection

Author contributions

Dr. Hu had full access to all the data in the study and took responsibility for the integrity of the data and the accuracy of the data analysis. Concept and design: Hu.Acquisition, analysis, or interpretation of data: All authors. Drafting the manuscript: Li, Zou. Critical revision of the manuscript for important intellectual content: All authors.Statistical analysis: Zhou, Wang, Zhang and Tan. Obtained funding: Hu. Administrative, technical, or material support: Liu and Hu.Supervision: Liu and Hu.

Funding

Dr. Hu is supported by Hubei Provincial Natural Science Foundation (grant number 2023AFB672).

Data availability

All data were extracted from published studies.

Declarations

Ethics approval and consent to participate

This study did not involve human participants or animals and therefore did not require ethics approval.

Consent for publication

Not applicable.

Competing interests

The authors declare no competing interests.