Home About us Current issue Back issues Submission Instructions Advertise Contact Login   

Search Article 
  
Advanced search 
 
Saudi Journal of Kidney Diseases and Transplantation
Users online: 947 Home Bookmark this page Print this page Email this page Small font sizeDefault font size Increase font size 
 


 
Table of Contents   
BRIEF COMMUNICATION  
Year : 2018  |  Volume : 29  |  Issue : 3  |  Page : 615-622
Determinants of patency of arteriovenous fistula in hemodialysis patients


1 Department of Nephrology, Dialysis and Kidney Transplantation, Rabta Hospital, Tunis, Tunisia
2 Research Laboratory of Renal Pathology LR00SP01, Tunis Medical School, Tunis el Manar University, Tunis, Tunisia

Click here for correspondence address and email

Date of Submission20-Jun-2017
Date of Acceptance22-Jul-2017
Date of Web Publication28-Jun-2018
 

   Abstract 

The arteriovenous fistula (AVF) is the vascular access of the first choice for hemodialysis (HD). Studies on patency of AVF and its affecting factors reveal a high risk for access failure. The aim of this study was to assess the primary and secondary AVF patency and their determinant factors. It was a retrospective, descriptive study conducted in the HD facility of the Nephrology Department in Rabta University Hospital. We included AVF created before December 2009 in end-stage renal disease (ESRD) patients. The end of the follow-up was fixed in December 2013. We included 126 AVFs created in 111 patients; 22.5% were aged >65 years, 39.6% were diabetic, 68.5% were hypertensive, and 26.1% had peripheral vascular disease. The primary patency rates were 78% at one year and 42% at five years. The secondary patency rates were 80% at one year and 69% at five years. Multivariate analysis revealed that the factors affecting the primary patency of AVF were: the use of jugular catheter for longer than three months (odds ratio (OR):1.91, P = 0.044) and a C-reactive protein >5 mg/L (OR: 1.7, P = 0.049). Aging (>65 years) (OR: 2.46, P = 0.042), referral time to a nephrologist <6 months before onset of ESRD (OR: 2.87, P = 0.015), absence of an antiplatelet therapy (OR: 4.47, P = 0.005), and serum phosphorus <45 mg/L (OR: 2.07, P = 0.045) were the significant impairing risk factors for secondary AVF patency. Our study suggests that early referral and creation of AVF and maturation before ESRD as well as its adequate monitoring are essential for maintaining patency.

How to cite this article:
Zouaghi MK, Lammouchi MA, Hassen M, Rais L, Krid M, Smaoui W, Jebali H, Kheder R, Hamida FB, Moussa FB, Fatma LB, Beji S. Determinants of patency of arteriovenous fistula in hemodialysis patients. Saudi J Kidney Dis Transpl 2018;29:615-22

How to cite this URL:
Zouaghi MK, Lammouchi MA, Hassen M, Rais L, Krid M, Smaoui W, Jebali H, Kheder R, Hamida FB, Moussa FB, Fatma LB, Beji S. Determinants of patency of arteriovenous fistula in hemodialysis patients. Saudi J Kidney Dis Transpl [serial online] 2018 [cited 2019 Aug 23];29:615-22. Available from: http://www.sjkdt.org/text.asp?2018/29/3/615/235183

   Introduction Top


The arteriovenous fistula (AVF) is the vascular access of choice for hemodialysis (HD).[1],[2] Its patency is the primary determinant of the effectiveness of the dialysis. The reported rate of primary and secondary patency of AVF is 60% and 71% at one year, respectively and, 55% and 65%, respectively at two years.[3] The main determinants of the patency of AVF are epidemiological, anatomical, clinical, biological, and pharmacological.[3],[4],[5] Their knowledge helps to identify the population at risk of failure of the vascular access. Few studies have focused on the patency of AVF in Tunisia and its determinants. The aim of our study was to evaluate the primary and secondary patency of AVF in patients with chronic renal failure on dialysis and to clarify their determinants.


   Methods Top


We conducted a descriptive, retrospective study at the nephrology department of the Rabta university hospital during five years from January 2009 to December 2013. We included patients with end-stage renal disease (ESRD) and the AVF had been created by the end of 2009. The end of the follow-up was fixed at December 31, 2013. We excluded patients with recovery of renal function during the first three months after the creation of the AVF. We defined:

  • Primary failure as the immediate failure of the AVF occurring within 72 postoperative hours, or the inability to successfully cannulate the AVF for HD within six months after its creation[6]
  • Primary patency was the time interval between AVF creation and its first thrombosis and any intervention for recanali-zation[6],[7]
  • Secondary patency was the time interval between AVF creation and abandonment with or without the intervention of recanalization.[6],[7]


Data collection was conducted from files and HD registers. We collected the following parameters at the time of creating the AVF: demographics (age and gender), comorbidities (hypertension, diabetes, peripheral arterial disease, coronary artery disease, heart failure, and smoking), the current treatment (renin-angio-tensin system blockers, calcium channel blockers, statins, antiplatelet therapy, and anticoagulants) , initial nephropathy, clinical data (systolic blood pressure, diastolic blood pressure, mean arterial pressure and pulse pressure, the body mass index, biological parameters (hemoglobin, C-reactive protein (CRP), corrected calcium, phosphorus, calcium × phospho-product, parathormone, serum albumin), and imaging. We specified the type of AVF and exploration data before creation of the AVF. We investigated the roles of these factors in determining the primary and secondary AVF permeability.


   Statistical Analysis Top


Data were entered and analyzed using Statistical Package for Social Sciences (SPSS) version 21.0 for Windows (SPSS Inc., Chicago, IL, USA). The study of patency was carried out by calculating the actuarial patency rates at six months and then annually from the date of AVF creation until the end of patency using the above-mentioned definitions, or the date of the last follow-up among patients with patent AVF. Kaplan–Meier survival curves were established and compared by the log-rank test. Death, loss of follow-up, and end of the study with patent AVF were not considered patency loss events. Multivariate analysis was performed by COX regression. A statistical difference was considered statistically significant if P <0.05.


   Results Top


One hundred and twenty-six AVFs were studied in 111 patients. Thirteen patients had two AVFs, and one patient had three. The average age of the patients was 52.7 years (20–81 years) and, 22.5% of patients were aged over 65 years. Eighty-one patients (80%) had, in addition to chronic kidney disease, at least one other chronic pathology. The duration of follow-up by the nephrologists before the onset of ESRD was more than six months in 45% of cases. Before the study, 69% of patients were dialyzed by internal jugular catheter (IJC). Demographic characteristics and clinical and biological parameters are summarized in [Table 1].
Table 1: Demographics, clinical and biological characteristics of the study population.

Click here to view


About 7% of patients had radial artery calcifications at the wrist. Venography was performed in 34.9% of cases. The creation of AVF occurred before onset of HD in only eight patients (7.2%). AVF was distal in 62.7% and proximal in 34.1% of patients [Figure 1]. The average duration of primary patency was 995.2 days ranging from 0 to 3150 days. The actuarial primary patency rate was 82 % at six months, 78% at one year, 69% at two years, 61% at four years and 42% at five years [Figure 2].
Figure 1: Vascular access type in the study patients.

Click here to view
Figure 2: a and b

Click here to view


The causes of primary patency loss were immediate primary failure (14 cases), thrombosis (20 cases), rupture of aneurysm (1 case), and recanalization (19 cases).

Recanalization procedures included arterio-venous replantation in six cases, percutaneous angioplasty in 12 cases and patch angioplasty in one case. Other causes of primary patency loss were death (28 cases) and lost to follow-up (2 cases). At the end of primary patency study, 42 AVFs (33 %) were still patent.

The average duration of secondary patency was 1124.07 days ranging from zero to 4263 days. The actuarial secondary patency rate was 83% at six months, 80% at one year, 74% at two years, 70% at four years, and 69% at five years [Figure 2]. The causes of secondary patency loss were immediate primary failure (14 cases), thrombosis (23 cases), and aneurysm rupture (1 case). Other causes of secondary patency loss were death (30 cases) and lost to follow-up (2 cases). At the end of the study, 56 AVFs (44.4%) were still patent. The factors affecting the patency of AVF on univariate analysis are illustrated in [Table 2]. Multivariate study found that CRP >5 mg/L and use of IJC for longer than three months, were primary patency impairing factors. Age >65 years, lack of antiplatelet drug intake, serum phosphorus <45 mg/L and duration of nephrology care before onset of ESRD of <6 months, impaired the secondary patency [Table 3].
Table 2: Factors influencing patency of arteriovenous fistula on univariate analysis.

Click here to view
Table 3: Factors affecting the patency of the arteriovenous fistula on multivariate analysis.

Click here to view



   Discussion Top


The AVF patency study and influencing factors help in determining the high-risk population for vascular access failure. Our study showed that the actuarial primary patency rate was 82% at six months, 78% at one year, 69% at two years, 61% at four years and 42% at five years. We found that two factors significantly decreased the primary patency: CRP >5 mg/L and use of IJC for more than three months. The actuarial secondary patency rate was 83% at six months, 80% at one year, 74% at two years, 70% at four years, and 69% at five years.

Age above 65 years, nonuse of anti-platelet drugs, nephrology care <6 months before the start of HD and phosphorus levels <45 mg/L significantly impaired the secondary patency in our patients.

The study of demographic, clinical, biological, anatomical and a follow-up of five years were the strong points of our study. On the other hand, the single-center retrospective character, the absence of some biological parameters and the absence of an AVF flow study were the weak points in this series. The primary and secondary patency rates in our study were similar to those reported by many authors,[3],[4],[8],[9] despite a specialized care that begins at an advanced stage of chronic kidney disease and late creation of AVF. The relatively young age of the patients in our study may explain these findings.

The influence of age on the patency of AVF is still controversial. A review of literature by Smith et al[10] on the factors influencing patency of AVF showed an increase of access failure in the elderly population. In a meta-analysis of 2007, Lazarides et al[11] showed a significant difference in secondary patency rates between the elderly and younger patients at 12 and 24 months with odds ratios (ORs) of 1.525 (P = 0.001) and 1.357 (P = 0.019). In our study, age >65 years impaired the secondary patency with an OR of 2.46 (P = 0.042). Other authors have demonstrated the negative impact of age on the primary and/or secondary patency rates.[8],[9] Comorbidities in the elderly including uremic or ischemic cardiomyopathy, atherosclerosis and diabetes, as well as poor veins, increased the risk of primary failure and impaired the patency of distal AVF.[8],[11]

On the other hand, Al-Jaishi et al[3] and Gibson et al[4] found that age had no effect on primary patency. These findings were also found in our series where age did not seem to influence the primary patency.

We did not find a significant effect of gender on AVF patency in our study. In a literature review of 2012, Smith et al[10] also found the same result. On the other hand, other studies found a negative impact of female gender on AVF patency and suggested that it could be explained by the small diameter of the vessels in women.[4],[12]

Diabetes mellitus is a risk factor for atherosclerosis in HD patients, which could explain the increased risk of AVF patency loss in patients with diabetes.[3],[8],[9] In our patients, diabetes was not an affecting factor on AVF patency. This result is shared by other authors.[4],[5] The precautions taken by surgeons before AVF creation, by vascular system study, reduce the risk of primary failure and patency loss of AVF in diabetes patients.[3],[9] A proper supervision of diabetes patients may reduce the risk of AVF failure.[8]

Few studies have checked the impact of the care period before the start of renal replacement on AVF patency. Ravani et al[13] showed that duration of this support <3 months was a risk factor of primary failure with a relative risk of 1.72. In our study, nephrology management time before the onset of ESRD was lower at six months in 55% of patients. These findings show the delay in instituting specialized management in our patients. We also found impairment of secondary patency in this population with a relative risk of 2.87.

The use of temporary vascular access, especially IJC, is the origin of local and systemic inflammatory reaction that can alter the AVF patency.[4],[9] In our study, we found a statistically significant relationship between prior use of an IJC for >3 months and the risk of primary patency loss (P <0.044). Several studies have focused on evaluating the effect of the use of antiplatelet agents on AVF patency. The meta-analysis of Da Silva et al[14] has demonstrated the protective effect of antiplatelet agents (aspirin, ticlopidine, clopidogrel, and dipyridamole) on AVF patency.

An earlier meta-analysis by the Antiplatelet Trialists' Collaboration[15] also had the same conclusions, that antiplatelet agents, mainly aspirin alone or aspirin and dipyridamole, greatly reduce the risk of vascular thrombosis in patients at high-risk for this complication. Our results also concluded that the use of antiplatelet agents is recommended to improve the patency of AVF in the absence of any contraindication.

Some authors have found CRP as a factor influencing the permeability of AVF. The elevation of CRP is known as a marker of chronic inflammation in ESRD patients.[16] CRP is a risk factor for atherosclerosis and cardiovascular events in this population.[16],[17] Therefore, an increase of CRP has a negative impact on AVF patency. In the series of Chou et al,[18] a CRP above 8 mg/L had a negative impact on AVF patency. We had the same result in our study for a CRP above 5 mg/L on the primary patency.

In contrast to what has been reported by many authors, hyperphosphatemia, recognized as a great marker of cardiovascular risk and AVF patency loss,[5],[19] was found in our study as a factor having a protective effect on the secondary patency AVF. Hyperphosphatemia could be explained either by good nutritional status or related to sufficient reserves of vitamin D. Some studies have shown that good nutrition plays a protective role on the permeability of the AVF.[20] It has been shown that vitamin D deficiency in HD is a cardiovascular risk factor and loss of AVF patency.[21] In our study, the dosage of vitamin D and nutritional parameters were not specified.


   Conclusion Top


This study shows that early nephrology management, the creation of AVF well before the start of HD and a decrease in the use of temporary vascular access improves AVF patency in patients with ESRD. A good multidisciplinary collaboration between nurses, surgeon, radiologist, and nephrologist is essential for better management of a vascular access.

Conflict of interest: None declared.

 
   References Top

1.
Allon M, Depner TA, Radeva M, et al. Impact of dialysis dose and membrane on infection-related hospitalization and death: Results of the HEMO study. J Am Soc Nephrol 2003; 14:1863-70.  Back to cited text no. 1
[PUBMED]    
2.
Hoen B, Paul-Dauphin A, Hestin D, Kessler M. EPIBACDIAL: A multicenter prospective study of risk factors for bacteremia in chronic hemodialysis patients. J Am Soc Nephrol 1998; 9:869-76.  Back to cited text no. 2
[PUBMED]    
3.
Al-Jaishi AA, Oliver MJ, Thomas SM, et al. Patency rates of the arteriovenous fistula for hemodialysis: A systematic review and meta-analysis. Am J Kidney Dis 2014;63:464-78.  Back to cited text no. 3
[PUBMED]    
4.
Gibson KD, Gillen DL, Caps MT, et al. Vascular access survival and incidence of revisions: A comparison of prosthetic grafts, simple autogenous fistulas, and venous transposition fistulas from the United States Renal Data System Dialysis Morbidity and Mortality Study. J Vasc Surg 2001;34:694-700.  Back to cited text no. 4
[PUBMED]    
5.
Asano M, Thumma J, Oguchi K, et al. Vascular access care and treatment practices associated with outcomes of arteriovenous fistula: International comparisons from the Dialysis Outcomes and Practice Patterns Study. Nephron Clin Pract 2013;124:23-30.  Back to cited text no. 5
[PUBMED]    
6.
Lee T, Mokrzycki M, Moist L, et al. Standardized definitions for hemodialysis vascular access. Semin Dial 2011;24:515-24.  Back to cited text no. 6
[PUBMED]    
7.
Sidawy AN, Gray R, Besarab A, et al. Recommended standards for reports dealing with arteriovenous hemodialysis accesses. J Vasc Surg 2002;35:603-10.  Back to cited text no. 7
[PUBMED]    
8.
Huijbregts HJ, Bots ML, Wittens CH, et al. Hemodialysis arteriovenous fistula patency revisited: Results of a prospective, multicenter initiative. Clin J Am Soc Nephrol 2008;3:714-9.  Back to cited text no. 8
[PUBMED]    
9.
Kim DS, Kim SW, Kim JC, et al. Clinical analysis of hemodialysis vascular access: Comparision of autogenous arterioveonus fistula & arteriovenous prosthetic graft. Korean J Thorac Cardiovasc Surg 2011;44:25-31.  Back to cited text no. 9
[PUBMED]    
10.
Smith GE, Gohil R, Chetter IC. Factors affecting the patency of arteriovenous fistulas for dialysis access. J Vasc Surg 2012;55:849-55.  Back to cited text no. 10
[PUBMED]    
11.
Lazarides MK, Georgiadis GS, Antoniou GA, Staramos DN. A meta-analysis of dialysis access outcome in elderly patients. J Vasc Surg 2007;45:420-6.  Back to cited text no. 11
[PUBMED]    
12.
Kazemzadeh GH, Modaghegh MH, Ravari H, Daliri M, Hoseini L, Nateghi M. Primary patency rate of native AV fistula: Long term follow up. Int J Clin Exp Med 2012;5:173-8.  Back to cited text no. 12
    
13.
Ravani P, Barrett B, Mandolfo S, et al. Factors associated with unsuccessful utilization and early failure of the arterio-venous fistula for hemodialysis. J Nephrol 2005;18:188-96.  Back to cited text no. 13
[PUBMED]    
14.
Da Silva AF, Escofet X, Rutherford PA. Medical adjuvant treatment to increase patency of arteriovenous fistulae and grafts. Cochrane Database Syst Rev 2003;(2):CD002786.  Back to cited text no. 14
    
15.
Collaborative overview of randomised trials of antiplatelet therapy - II: Maintenance of vascular graft or arterial patency by antiplatelet therapy. Antiplatelet trialists' collaboration. BMJ 1994;308:159-68.  Back to cited text no. 15
    
16.
Kim BS, Jeon DS, Shin MJ, et al. Persistent elevation of C-reactive protein may predict cardiac hypertrophy and dysfunction in patients maintained on hemodialysis. Am J Nephrol 2005;25:189-95.  Back to cited text no. 16
[PUBMED]    
17.
Matsumae T, Abe Y, Murakami G, et al. Determinants of arterial wall stiffness and peripheral artery occlusive disease in non-diabetic hemodialysis patients. Hypertens Res 2007;30:377-85.  Back to cited text no. 17
[PUBMED]    
18.
Chou CY, Kuo HL, Yung YF, Liu YL, Huang CC. C-reactive protein predicts vascular access thrombosis in hemodialysis patients. Blood Purif 2006;24:342-6.  Back to cited text no. 18
[PUBMED]    
19.
Morena M, Bosc JY, Jaussent I, et al. The role of mineral metabolism and inflammation on dialysis vascular access failure. J Vasc Access 2006;7:77-82.  Back to cited text no. 19
[PUBMED]    
20.
Gagliardi GM, Mancuso D, Falbo E, et al. Anthropometric parameters of nutritional assessment as predictive factors of arteriovenous fistula malfunction in patients undergoing hemodialysis. J Vasc Access 2012;13:475-81.  Back to cited text no. 20
[PUBMED]    
21.
Walker JP, Hiramoto JS, Gasper WJ, et al. Vitamin D deficiency is associated with mortality and adverse vascular access outcomes in patients with end-stage renal disease. J Vasc Surg 2014;60:176-83.  Back to cited text no. 21
[PUBMED]    

Top
Correspondence Address:
Dr. Mohamed Ali Lammouchi
Department of Nephrology, Dialysis and Kidney Transplantation, Rabta Hospital, Tunis
Tunisia
Login to access the Email id


DOI: 10.4103/1319-2442.235183

PMID: 29970738

Rights and Permissions


    Figures

  [Figure 1], [Figure 2]
 
 
    Tables

  [Table 1], [Table 2], [Table 3]



 

Top
   
 
 
    Similar in PUBMED
    Search Pubmed for
    Search in Google Scholar for
    Email Alert *
    Add to My List *
* Registration required (free)  
 


 
    Abstract
   Introduction
   Methods
   Statistical Analysis
   Results
   Discussion
   Conclusion
    References
    Article Figures
    Article Tables
 

 Article Access Statistics
    Viewed1338    
    Printed12    
    Emailed0    
    PDF Downloaded210    
    Comments [Add]    

Recommend this journal