Background
One of the most important aspects for successful maintenance of hemodialysis in end-stage renal disease (ESRD) patients is the integrity of the vascular access [1]. Access dysfunction due to thrombosis is the most common cause of hospitalization among maintenance hemodialysis patients [2]. This dysfunction or thrombosis is a major prevalent clinical problem accounting for an average of 17% of hemodialysis patient admissions in one study [3] with $500 million to $1.3 billion spent each year in the United States to maintain a viable vascular access and control serious morbidity [3,4, 5,6]. Little is understood about risk factors associated with vascular access thrombosis (VAT) with the problem being described as “ill defined” [4]. Though pathology in End-Stage Renal Disease (ESRD) patients with high total homocysteine (tHcy) can be established, the research findings with vascular access thrombosis (VAT) and tHcy are equivocal. Investigators have found significantly higher homocysteine levels in patients with recurrent VAT compared with one or less episodes of thrombosis [9]. Initial prospective evidence supports an independent association between tHcy levels and access thrombosis [2]. The purpose of this study was to determine if significant associations exist between tHcy, age, gender, previous morbidity (diabetes and hypertension) and the number of vascular access thromboses in patients with ESRD.
Methods
One hundred and four (N=104) patients undergoing dialysis were selected. The experimental group participants were identified as those having one or more vascular access thromboses (VAT) during the previous 14-month period (November 2000 to January 2002) and the control group participants were those with no VAT during the same period. Additional sub-group analyses included the following: a) hypertensive vs. normotensive; b) diabetes mellitus, Type I, Type II, and none; c) gender; d) age.
Results
The two-sample t-Test for variance between groups revealed no significant difference in tHcy values between groups (F-ratio=1.02, p=0.095) and no significant differences in tHcy and age (F-ratio=1.26, p=0.47). ANOVA revealed hypertensives were not significantly different (F-ratio=0.78, p=0.38) from normotensives in terms of VAT and between those without diabetes with Type I and Type II (F-ratio=0.06, p=0.94).
Conclusions
While some studies have demonstrated a relationship between tHcy and VAT, this study found chronically high homocysteine levels in patients with ESRD were not associated with incidence of VAT. There were no significant differences in the number of VAT’s across additional variables of age, gender, and previous morbidity. No significant interactions were discovered.