Performance Characteristics of Candidate Criteria for Hemodialysis Arteriovenous Fistula Maturation.

BACKGROUND: Twenty to 60% of newly created hemodialysis arteriovenous fistulas do not mature adequately for use. One barrier to developing interventions to improve fistula outcomes is a lack of standardized criteria for maturation. METHODS: Using data from the multicenter, prospective Hemodialysis Fistula Maturation (HFM) Study, we determined sensitivities, specificities, and positive and negative predictive values of multiple candidate maturation criteria using the HFM Study maturation criteria as the reference. We also compared, across the maturation criteria, relationships between maturation and fistula survival using Cox proportional hazards models. RESULTS: We included 535 of the 602 HFM Study participants. The median (interquartile range) age was 57 (47-65) years, 70% were men, and 45% were Black participants. Depending on the criterion and time frame for ascertainment (3, 4, 5, 6, or 9 months), sensitivities ranged from 57% to 100%, specificities ranged from 85% to 100%, positive predictive values ranged from 88% to 100%, and negative predictive values ranged from 65% to 100%. For all criteria, areas under the curve for the 6-month (0.90-0.97 for unassisted maturation and 0.89-0.95 for overall maturation) and 9-month time frames were similar. Attainment of unassisted maturation was associated with lower risks of fistula abandonment, with hazard ratios ranging from 0.10 to 0.40 depending on the criterion and time frame. Eliminating dialysis adequacy indicators, or simplifying the criteria in other ways, had little effect on performance characteristics. CONCLUSIONS: High performance characteristics are maintained with maturation criteria that are simpler and less burdensome to ascertain than the HFM Study outcome measure.

Association between anaesthesia type and arteriovenous fistula maturation.

Background: Whereas general anaesthesia is commonly used for haemodialysis fistula creation, regional or local anaesthesia has been posited to lead to better fistula maturation outcomes. We sought to measure the association between anaesthesia type and arteriovenous fistula maturation. Methods: We performed a secondary analysis of data from the Hemodialysis Fistula Maturation study, a multicentre prospective cohort study of advanced chronic kidney disease patients who underwent single-stage upper extremity fistula creation between 2010 and 2013. We evaluated the relationship between anaesthesia type and unassisted (without maturation-facilitating interventions) or overall (unassisted or assisted) fistula maturation using multivariable logistic regression. Results: Among 602 participants, 336 (55.8%) received regional/local anaesthesia and 266 (44.2%) received general anaesthesia. Unassisted maturation occurred in 164/309 patients (53.1%) after regional/local vs 91/226 patients (40.3%) after general anaesthesia (P=0.003). After adjustment for patient factors and fistula type, regional/local anaesthesia was associated with greater odds of unassisted maturation than general anaesthesia (odds ratio 1.72, 95% confidence interval 1.24-2.39; P=0.001). However, after further adjustment for clinical centre fixed effects, odds of unassisted maturation did not differ by anaesthesia type (odds ratio 1.03, 95% confidence interval 0.78-1.36; P=0.830). Similar findings were observed for overall maturation and composite endpoints accounting for potential survivorship bias. Conclusions: Regional/local anaesthesia was associated with increased odds of fistula maturation when adjusting for patient factors and fistula type. However, this association did not persist after adjusting for centre fixed effects. Future research is needed to better understand the relationship between anaesthesia type and centre factors to optimise outcomes after fistula surgery.

Illness perception in patients with chronic kidney disease and kidney failure: a scoping review protocol.

INTRODUCTION: Patient education is a crucial component in the management of chronic kidney disease (CKD); however, many education programmes do not tailor to patients' disease-related belief and emotional reactions. According to Leventhal's self-regulation model, such beliefs and reactions, known as illness perceptions, are a part of patients' understanding of their disease and treatment-related actions. The existing research of illness perception in the field of nephrology has been heterogenous in terms of study outcomes and in study population; and the evidence of how illness perceptions affect behavioural and decisional outcomes is limited. This scoping review aims to map and summarise the evidence of published literature on illness perception among patients with CKD not yet treated by dialysis and kidney failure. METHODS AND ANALYSIS: This study bases its approach on Joanna Brigg's Institute Guidelines on scoping review methods. The search strategy was developed together with a medical information specialist. Searches will be performed on acceptance of publication in the following databases: PubMed, EMBASE, PsycINFO via Ovid, Scopus and the Cumulative Index to Nursing and Allied Health Literature. Searches will be run without incorporating a date restriction in order to capture content from the databases' inception to present day. Search terms including 'illness perception', 'kidney disease' and 'kidney failure' will be screened in titles and abstracts. Two independent researchers will screen the abstracts and full text for full eligibility. We will include studies focusing on illness perception of patients with CKD with estimated glomerular filtration rate <60 mL/min/1.73 m2, kidney failure or recipients of kidney transplant. We will exclude patients <18 years of age, patients with acute kidney injury and non-English articles. All demographic data, study design and study findings will be collected and analysed using a data abstraction tool. ETHICS AND DISSEMINATION: This study does not require internal review board approval. We will present the findings of this scoping review in a peer-reviewed journal.