Frailty, CRP, Age Predict Death in ANCA Vasculitis

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Frailty score, age and C-reactive protein (CRP) are associated with mortality in elderly patients with anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis, say researchers writing in Rheumatology this fall.

In this real-world single-center study, frailty was assessed on on Health and Aging Clinical Frailty Scale, which is also referred to as Rockwood's Clinical Frailty Scale, that measures factors such as activity levels, symptoms, and dependency on others for activities of daily living.

While the increasing age association was not surprising, the authors, who were led by Neeraj Dhaun, M.D., of the University of Edinburgh in Scotland, wrote "That a frailty score was also associated with mortality-even after adjusting for age and other potentially confounding variables -- suggests that this simple tool might provide useful additional information about elderly patients with ANCA vasculitis."

While this small-vessel vasculitis can develop at any age, it most often occurs in the seventh and eighth decades, when patients are vulnerable to the effects of the disease and its treatment. Older age and impaired function have been reported to be associated with poor disease outcomes, but such research, which is limited by small population subgroups, occurred before extensive use of rituximab. Additionally, elderly patients are under-represented in randomized controlled trials of induction immunosuppression in ANCA vasculitis.

Researchers consecutively recruited 83 patients with a median age of 74 years, who were followed for approximately 3.3 years, to assess long-term outcomes ANCA vasculitis in older patients and whether the pre-morbid frailty score could aid prognosis.

Two- and five-year survival were 83 percent (95% CI 75, 92%) and 75 percent (95% CI 65, 86%), respectively. During the first three months, the median cumulative dose of oral prednisolone was 2,030 mg, while only one patient received intravenous glucocorticoids. Age (HR per year 1.134, 95% CI 1.012-1.271), frailty score (HR 2.07, 95% CI 1.50-2.87) and and CRP level above 149 mg/L (HR 5.717, 95% CI 1.012-32.287) were independently associated with mortality; all deaths occurred in patients aged over 75 years at presentation.

At baseline, the mean frailty score was 3. After adjustment for age, sex, ANCA status, kidney function, CRP, the hazard ratio remained at 1.90 (95% CI 1.03-3.52). “Patients aged 75 years or older, or with a Rockwood Clinical Frailty score of 4 or greater, have higher mortality,” wrote the authors.

Participants treated with a cyclophosphamide-based induction regimen were younger than those treated with rituximab or mycophenolate mofetil. Survival was better in the cyclophosphamide-treated group.

“A glucocorticoid-sparing regimen can give good long-term clinical outcomes in ANCA vasculitis in the elderly,” the authors wrote.

REFERENCE:  Dominic McGovern, Sam P Williams, Katrina Parsons, et al. “Long-term outcomes in elderly patients with ANCA-associated vasculitis.” Rheumatology. September 17, 2019. doi.org/10.1093/rheumatology/kez388