Plasma Exchange for ANCA-Associated Vasculitis: An International Survey of Patient Preferences

Abstract

We sought to elicit patient preferences regarding the use of plasma exchange in antineutrophil cytoplasmic antibody-associated vasculitis (AAV) and its tradeoffs of risk of kidney failure and risk of serious infection. Patient survey. The online survey was circulated to adults with AAV via kidney and vasculitis networks in Canada, the United Kingdom, and the United States. Respondents reviewed the estimated 1-year risks of kidney failure and serious infection in AAV with and without plasma exchange across 5 serum creatinine categories (150, 250, 350, 450, and 600μmol/L). For each scenario, participants indicated whether or not they would choose plasma exchange. Responses were assessed with multilevel multivariable logistic regression models to identify predictors of respondent choice regarding treatment with plasma exchange. The 470 respondents from the 13 countries (United States 61.7%, United Kingdom 20.0%, Canada 13.8%, and other countries 4.5%) had a mean age of 58.6 (SD 14.3) years, 70.2% women. Respondents were more likely to choose plasma exchange in scenarios at high risk of kidney failure and serious infection (creatinine level of 350 or 450μmol/L) compared with lower risk scenarios or the highest risk scenario. However, 145 (30.9%) chose plasma exchange across all scenarios, whereas 80 (17.0%) declined plasma exchange across all scenarios. Respondents from the United Kingdom (OR, 2.61; 95% CI, 1.09-6.22) who received previous dialysis (OR, 2.70; 95% CI, 1.12-6.52) or received previous plasma exchange (OR, 5.62; 95% CI, 2.72-11.61) were more likely to choose plasma exchange, whereas older respondents (OR, 0.98; 95% CI, 0.96-0.99 per 1 year increase) were less likely. Unclear generalizability to non-English-speaking, older, and less health literate adults, possible responder bias, survivor bias, lack of individualized risk assessments for kidney failure, and serious infection. Patients with AAV do not express a consistent choice for plasma exchange, which highlights the need for shared decision making.