Outcomes of the First and Second Hemodialysis Fistula: A Cohort Study

RATIONALE & OBJECTIVE

Fistulas are the preferred form of hemodialysis access; however, many fistulas fail to mature into usable accesses after creation. Data for outcomes after placement of a second fistula are limited.

STUDY DESIGN

Cohort study.

SETTING & PARTICIPANTS

People who initiated hemodialysis therapy in any of 5 Canadian dialysis programs (2004-2012) and had at least 1 hemodialysis fistula placed.

PREDICTOR

Second versus initial fistula; receipt of 2 versus 1 fistula; second versus first fistula in recipients of 2 fistulas.

OUTCOMES

Catheter-free fistula use during 1 year following initiation of hemodialysis therapy or following fistula creation, if created after hemodialysis therapy start; proportion of time with catheter-free use; time to catheter free use; time of functional patency.

ANALYTICAL APPROACH

Logistic regression; fractional regression.

RESULTS

Among the 1,091 study participants (mean age, 64±15 [SD] years; 63% men; 59% with diabetes), 901 received 1 and 190 received 2 fistulas. 38% of second fistulas versus 46% of first fistulas were used catheter free at least once. Average percentages of time that second and initial fistulas were used catheter free were 34% and 42%, respectively (OR, 0.72; 95% CI, 0.54-0.94). Compared with people who received 1 fistula, those who received 2 fistulas were less likely to achieve catheter-free use (26% vs 56%) and remain catheter free (23% vs 49% of time; OR, 0.30, 95% CI, 0.24-0.39). Among people who received 2 fistulas, the proportion of time that the second fistula was used catheter free was 11% higher with each 10% greater proportion of time that the first fistula was used catheter free (95% CI, 1%-22%). Model discrimination was modest (C index, 0.69).

LIMITATIONS

Unknown criteria for patient selection for 1 or 2 fistulas; unknown reasons for prolonged catheter use.

CONCLUSIONS

Outcomes of a second fistula may be inferior to outcomes of the initial fistula. First and second fistula outcomes are weakly correlated and difficult to predict based on clinical characteristics.

Multi-Disciplinary Vascular Access Care and Access Outcomes in People Starting Hemodialysis Therapy

BACKGROUND AND OBJECTIVES

Fistulas, the preferred form of hemodialysis access, are difficult to establish and maintain. We examined the effect of a multidisciplinary vascular access team, including nurses, surgeons, and radiologists, on the probability of using a fistula catheter-free, and rates of access-related procedures in incident patients receiving hemodialysis.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We examined vascular access outcomes in the first year of hemodialysis treatment before (2004-2005, preteam period) and after the implementation of an access team (2006-2008, early-team period; 2009-2011, late-team period) in the Calgary Health Region, Canada. We used logistic regression to study the probability of fistula creation and the probability of catheter-free fistula use, and negative binomial regression to study access-related procedure rates.

RESULTS

We included 609 adults (mean age, 65 [±15] years; 61% men; 54% with diabetes). By the end of the first year of hemodialysis, 102 participants received a fistula in the preteam period (70%), 196 (78%) in the early-team period (odds ratios versus preteam, 1.47; 95% confidence interval, 0.92 to 2.35), and 139 (66%) in the late-team period (0.85; 0.54 to 1.35). Access team implementation did not affect the probability of catheter-free use of the fistula (odds ratio, 0.87; 95% confidence interval, 0.52 to 1.43, for the early; and 0.89; 0.52 to 1.53, for the late team versus preteam period). Participants underwent an average of 4-5 total access-related procedures during the first year of hemodialysis, with higher rates in women and in people with comorbidities. Catheter-related procedure rates were similar before and after team implementation; relative to the preteam period, fistula-related procedure rates were 40% (20%-60%) and 30% (10%-50%) higher in the early-team and late-team periods, respectively.

CONCLUSION

Introduction of a multidisciplinary access team did not increase the probability of catheter-free fistula use, but resulted in higher rates of fistula-related procedures.

The Effect of Predialysis Fistula Attempt on Risk of All-Cause and Access-Related Death

Whether the lower risk of mortality associated with arteriovenous fistula use in hemodialysis patients is due to the avoidance of catheters or if healthier patients are simply more likely to have fistulas placed is unknown. To provide clarification, we determined the proportion of access-related deaths in a retrospective cohort study of patients aged ≥18 years who initiated hemodialysis between 2004 and 2012 at five Canadian dialysis programs. A total of 3168 patients initiated dialysis at the participating centers; 2300 met our inclusion criteria. Two investigators independently adjudicated cause of death using explicit criteria and determined whether a death was access-related. We observed significantly lower mortality in individuals who underwent a predialysis fistula attempt than in those without a predialysis fistula attempt in patients aged <65 years (hazard ratio [HR], 0.49; 95% confidence interval [95% CI], 0.29 to 0.82) and in the first 2 years of follow-up in those aged ≥65 years (HR_{0-24 months}, 0.60; 95% CI, 0.43 to 0.84; HR_{24+ months}, 1.83; 95% CI, 1.25 to 2.67). Sudden deaths that occurred out of hospital accounted for most of the deaths, followed by deaths due to cardiovascular disease and infectious complications. We found only 2.3% of deaths to be access-related. In conclusion, predialysis fistula attempt may associate with a lower risk of mortality. However, the excess mortality observed in patients treated with catheters does not appear to be due to direct, access-related complications but is likely the result of residual confounding, unmeasured comorbidity, or treatment selection bias.

Dermatological findings in early detection of complex regional pain syndrome

IMPORTANCE

Complex regional pain syndrome (CRPS) is a chronic pain condition usually affecting the extremities. It mostly occurs in 3 distinct stages with intense pain being the hallmark feature in every stage. Skin abnormalities are common, and often necessary, in the clinical findings required to diagnose CRPS.

OBSERVATIONS

A man in his 30s presented to the dermatology clinic with complaints of recurrent redness, swelling, and burning pain in his left arm. Based on this clinical presentation with normal findings from a neurological examination and unremarkable findings on diagnostic imaging, the diagnosis of CRPS was made.

CONCLUSIONS AND RELEVANCE

It is important for dermatologists to understand and recognize CRPS as a neurological disorder with major dermatologic implications. The ability of dermatologists to identify and direct patients with this syndrome is a critical factor in determining the likelihood of favorable outcomes following diagnosis of CRPS. This report outlines and reviews a neurological condition presenting with clinically significant cutaneous changes. We illustrate the bias that dermatologists may have in exclusively associating patient complaints with dermatological implications. This stresses the necessity for dermatologists to perform comprehensive medical histories and physical examinations to minimize diagnostic error and improve patient care.

Risk of death following kidney allograft failure: a systematic review and meta-analysis of cohort studies

BACKGROUND

People with kidney allograft failure represent an increasing fraction of all those starting dialysis therapy. We sought to summarize prognosis following kidney allograft failure and identify potentially beneficial interventions or modifiable risk factors.

METHODS

We searched MEDLINE and EMBASE (inception to 1 October 2013) and article reference lists without language restriction and selected cohort studies of all-cause mortality and fatal infection-related and cardiovascular events in people starting dialysis following kidney allograft failure. Two reviewers independently extracted data on study design, participant characteristics, dialysis modality, transplant nephrectomy, immunosuppression strategy, transplant-naive comparators and risk of bias. Discrepancies were resolved with a third reviewer.

RESULTS

Forty studies comprising 249 716 participants met the inclusion criteria. The first year of dialysis therapy was associated with the highest mortality. By random effects meta-analysis, annual risk of death, from years 1 to 4, was 0.12 [95% confidence interval (95% CI): 0.09-0.15], 0.06 (95% CI: 0.05-0.07), 0.05 (95% CI: 0.04-0.06) and 0.05 (95% CI: 0.04-0.06), respectively. We found high heterogeneity in each meta-analysis, which remained unexplained by prespecified subgroup analyses. We could not find sufficient information to summarize the risk for fatal infection-related and cardiovascular events, or to test the role of transplant nephrectomy or different immunosuppressive strategies. Risk of bias was high, especially participation bias.

CONCLUSION

Mortality is higher during the first year of dialysis treatment following kidney allograft failure than in subsequent years. Insufficient data are available to assess factors or interventions potentially impacting prognosis following kidney allograft failure. In a culture promoting transplantation, clinical research of different models of care in this growing high-risk population should be a research priority.