A mixed-methods investigation of incident Hemodialysis access in a safety-net population

This study was conducted in an outpatient HD unit that is affiliated with an urban safety-net hospital. We performed a retrospective review of all adults who initiated HD at this hospital either as inpatients or outpatients, and who went on to continue outpatient HD treatments at this facility, with HD initiation dates between January 1st, 2010 and December 31st, 2015. Patients were excluded if they were initiated on HD briefly while being bridged to peritoneal dialysis (n = 11). Data were collected primarily from the Centers for Medicare & Medicaid Services Form 2728, which is submitted for each patient at the time of HD initiation. The primary outcome was vascular access modality at the time of HD initiation, modeled as a binary variable: surgical access (which included both AVF and arteriovenous [AV] graft) or CVC (with or without maturing surgical access in place). Predictors included variables that have been described nationally, but also those that might disproportionately affect our population: age, gender, race/ethnicity (white, black, Hispanic, Asian, other/unknown), limited English proficiency (obtained from electronic medical records), comorbid conditions previously identified as significantly correlated with patient survival in the ESRD population (congestive heart failure, hypertension, chronic obstructive pulmonary disease (COPD), peripheral vascular disease, amputation, diabetes, drug abuse, cancer), body mass index (BMI), etiology of renal failure, income quintile (estimated using census data for patient zip code), insurance status (Medicare only, Medicaid only, Medicare & Medicaid, none, other), duration of pre-hemodialysis nephrology care, and year of HD initiation. [12‐14] Because dedicated vascular surgical services became available to this population in August 2012, we constructed a pre/post 2012 term to examine whether access to on-site vascular surgery services was associated with incident CVC use.

In order to contextualize our quantitative results and develop strategies to address high rates of incident CVC use, we performed one-on-one interviews with a sample of patients from the study population who had initiated HD in the prior year. Primary nephrologists were asked to exclude potential interview patients with psychiatric co-morbidities and dementia. Patients deemed appropriate were subsequently approached and asked to provide informed consent. A single investigator (NR) performed all interviews using a standard list of questions regarding the barriers patients had experienced in the process of obtaining vascular access for HD, and their suggestions to improve the process. Interviews with patients with limited English proficiency were conducted with the aid of professional interpreter services via telephone. All interviews were audiotaped and professionally transcribed. Interview transcripts were interpreted by using directed content analysis, in which a previously described theoretical model is applied and extended in order to create initial coding categories [15]. A theoretical model describing multilevel barriers leading to healthcare disparities was extended to incorporate patient experiences and suggestions for improving care [16]. Three broad coding categories were created: barriers to care, attitudes toward care, and suggestions for care. Three investigators independently read and coded interview transcripts using this framework and then arrived at a consensus on the main themes encountered within each broad coding category. Based on agreement upon the adequate detail and variety of data within each theme, the authors agreed that saturation had been reached [17]. The University of California, San Francisco institutional review board approved all portions of this study.

Our cohort consisted of 241 patients with a mean age of 52.4 years (range = 21–86), of whom 61.8% were male. They were racially and ethnically diverse (19.5% white, 29.5% black, 28.6% Hispanic, 17.4% Asian). Forty-two percent were uninsured and an additional 39% were covered only by Medicaid (Table 1). Twenty-four percent had limited English proficiency (LEP), speaking a variety of primary languages including Spanish, Chinese, Vietnamese, and Tagalog.

Overall, 10.0% of patients initiated HD using an AVF and 2.1% using an AV graft, while 87.9% of patients initiated HD using a CVC, which included 6.2% who had a maturing AVF or nonfunctional AV graft in place (Fig. 1). When examined by year of HD initiation, an increase in the annual rate of incident surgical access (AVF or AV graft) was identified (Fig. 2).

Odds of initiating HD with a CVC, as predicted by univariate logistic regression and a restricted multivariable logistic model are displayed in Table 2. Patient clinical and demographic characteristics were not significantly associated with incident CVC use. Uninsured status, duration of pre-dialysis nephrology care, and HD initiation pre/post 2012 were significantly associated with incident CVC use in univariate analyses. Of these predictors, all remained significant predictors of incident CVC use in the multivariable logistic model except for timing of HD initiation (odds ratio in univariate analysis =0.40, 95% CI 0.16–0.98; adjusted odds ratio [aOR] in multivariable analysis =0.48, 0.17–1.36).

In the multivariable model, patients who were uninsured had a nearly four-fold increase in odds of incident CVC use compared to patients with Medicaid (aOR = 3.96, 1.23–12.76). We found a graded association between duration of pre-dialysis nephrology care and odds of incident CVC use. Compared to patients with less than six months of pre-dialysis nephrology care, those with 6–12 months had a 77% decreased odds (aOR = 0.23, 0.06–0.90), and those with over 12 months had a 93% decreased odds of initiating HD with a CVC (aOR = 0.07, 0.02–0.23).

Ten patients who had initiated HD within the prior year participated in the interviews. Half of the participants were English speakers and the remainder spoke a variety of other languages. Eight of the participants were male, with a mean age of 54.4 years (range = 39–65). Half of the participants had initiated HD using an AVF and half had initiated with a CVC. The major themes in patient responses are presented in Table 3, categorized into three broad groups: stress & emotional barriers, limited resources, and patient suggestions for vascular access care coordination.

Participants experienced strong emotional responses to either their diagnosis of renal failure, or the impending need for HD and/or surgery. They reported feeling anxiety, depression, panic, denial, and frustration. Some participants described how these emotional states impaired their ability to make the decisions necessary to coordinate surgery for AVF placement. One patient who started HD using an AVF had the insight to look back at his decision making in the months leading to HD initiation and state:

“I think a patient can be traumatized by the experience of now knowing that the patient needs dialysis and that sometimes can create anxiety and the slowing of the thinking process and making prudent decisions, regardless of the level of responsibility that that patient has exhibited in the past.”.

Attitudes toward healthcare providers at the dialysis unit were overwhelmingly positive. Despite this, some patients reported that their emotional responses made it difficult to participate in their own care. Multiple participants expressed a deep sense of loss at the time of HD initiation that resulted from no longer being able to work or travel, newly imposed dietary restrictions, and the physical changes that their disease or even the AVF surgery itself caused. Some participants were self-conscious about the way the AVF looked, commenting on new considerations for how their clothing concealed the AVF. One participant who initiated HD using an AVF described all of this as “an abnormal human situation.”

Misconceptions and poor quality information were barriers to timely AVF placement. Multiple participants reported anticipating substantial pain from AVF surgery and cannulation, only to discover that their fears overshadowed the reality. One participant who started HD using a CVC wished he had “somebody to lay it out and give you an idea of what a fistula is all about. That would’ve helped tremendously. . . all of my information came in pieces and bits.” Other participants reported heightened anxiety caused by misinformation that they received from acquaintances. One participant who started HD using an AVF stated, “I just get a rundown in the streets, people dying, they take dope on dialysis and die.”.

Limited social and financial resources associated with homelessness and poverty were barriers to complying with the care needed to have an AVF placed. One participant who attributed his kidney disease to years of drug abuse and had started HD using a CVC stated, “I’m still struggling with the things that got me to this point right here. The environment I'm in and the area I stay at, it’s just—it’s bad.” Other participants who had initiated HD using a CVC also cited a lack of reliable transportation, and poor social support during times of illness as barriers to keeping medical appointments before initiating HD.

Participants’ responses regarding language as a potential barrier to care were mixed. Most reported that they were able to easily get interpreter services when needed. However, one participant with LEP who had initiated HD using a CVC did describe challenges in communicating with her doctor, stating, “Who do I talk to? Everyone here only speaks English.” Additionally, participants with LEP who had initiated HD using a CVC identified a lack of insurance coverage as a barrier to receiving pre-ESRD care, whereas English speakers did not. LEP participants described inconsistent primary care, limited access to essential medications, and deficiencies in their own medical knowledge that contributed to progression of kidney disease, delays in ESRD diagnosis, and delayed AVF placement.

Enhanced delivery of information was a common desire when participants were asked for suggestions to improve timely AVF placement. Participants reported that more information would have helped to allay their fears and shape their expectations for the better. Opinions on the best way to receive information varied widely; suggestions included educational videos, face-to-face interactions, printed material, or online forums. One participant who started HD using an AVF stated, “I think that new patients can benefit from seeing what current patients experience. . . as opposed to just watching a[n educational] video.” This participant felt that an experienced patient could describe “the physical effects and the psychological effects” of AVF placement and HD more effectively than a doctor could. Another participant who had started HD using an AVF cited an interaction with another patient that helped him overcome his fear of AVF cannulation: “He told me, he says he was scared the first time he did it. But he said once you did it, no problem.”.

Multiple participants who had initiated HD using both AVFs and CVCs suggested that a group setting would be ideal for pre-dialysis patients to meet with more experienced patients who could address their questions and anxieties. One participant proposed: “Why don’t they have like an AA meeting and have a bunch of people. . . share about dialysis and stuff.” Another participant suggested that patients gather to “drink coffee or something and talk about their experience. Not a big group, just a few people. ‘How are you feeling? Are you okay?’”.