The association between multimorbidity and arteriovenous fistula creation outcomes.

Abstract

The multimorbidity weighted index (MWI) quantifies both cumulative disease burden and its impact on physical functioning. This study examined the association between MWI and short-term outcomes of arteriovenous fistula (AVF) creation for hemodialysis access. We performed a retrospective review of AVFs created between January 2011 and December 2019 of national Vascular Quality Initiative data linked to United States Renal Data Systems data. The primary exposure was multimorbidity as measured by the MWI. The MWI was dichotomized as above or below the median. The primary outcome was functional AVF use within 6 months. Multivariable logistic regression was performed with age, sex, race, cannulation site, and MWI as covariates. A total of 9023 patients were included. The mean age was 65 years and the cohort was predominantly male and identified as White. The median follow-up was 14 months (interquartile range, 3-33 months). The median MWI was 8.3. Of the 9023 AVF created, 5578 (61.8%) were used within 6 months of creation, and the median time to first use was 4 months (interquartile range, 3-5 months). Upper arm AVFs were more likely to be used within 6 months than forearm (62.7% vs 59.4%; P = .004). Of the 5578 patients who used their access within 6 months, 2199 (39.4%) required at least one revision before first AVF use, with most undergoing one (73.8%) or two (21.3%) revisions. Patients with an MWI greater than the median (>MED) compared with patients with MWI less than or equal to the median (<MED) were less likely to use their AVF within 6 months (58.9% vs 64.6%; P < .001) and more likely to undergo revision before first AVF use (43.2% vs 36.2%; P < .001). The median survival was shorter for patients in >MED (35 months vs 50 months; P < .001). On multivariable analysis, MWI >MED, female sex, Black race, and age >80 years were associated with a decreased odds of AVF use within 6 months. An MWI >MED, female sex, Asian and Black race, and upper arm cannulation site were associated with an increased odds of undergoing a revision before first AVF use. Patients undergoing AVF creation have a high MWI. In this cohort, a higher MWI was associated with increased mortality, a lower likelihood of AVF use within 6 months, and greater odds of revision before first AVF use. The MWI may be a valuable adjunct to guide vascular access planning and shared decision-making.