Long-term outcomes of patients with Takayasu arteritis and renal artery involvement: a cohort study.

Objective: To describe the long-term outcomes of patients with Takayasu arteritis (TAK) and renal artery involvement (RAI).
Methods: A retrospective review of 122 patients with TAK at three tertiary centres in Canada, Sweden and the UK. Data on demographics, laboratory and clinical parameters, medications and angiography findings were collected. Non-renal and renal parameters were compared at baseline and follow-up.
Results: A total of 37 patients (30%) with RAI were identified: 18 (49%) with unilateral and 19 (51%) with bilateral RAI. Patients were predominantly female (89%). The median age at diagnosis was 27 years [interquartile range (IQR) 16-38]. The median follow-up time was 7 years (IQR 2-12). Hypertension was seen in 27 patients (73%) at presentation and 25 (68%) at follow-up. The median estimated glomerular filtration (eGFR) at presentation was 94 and 98 ml/min/1.73 m ² in those with unilateral and bilateral RAI, respectively. The corresponding median eGFR at follow-up was 101.5 and 104 ml/min/1.73 m ² , respectively. Three patients at presentation and two at follow-up had an eGFR of <60 ml/min/1.73 m ² . Five underwent endovascular intervention and three required surgical interventions. Among the 33 patients with radiologic follow-up, 23 (69%) had persistent RAI and 10 (30%) had resolution of RAI. One (6%) patient with unilateral RAI developed bilateral RAI and three (19%) with bilateral RAI regressed to unilateral RAI. Over time, 23 (62%) patients had stable renal function, 7 (19%) had improvement and 4 had a decline in renal function; no patient developed end-stage renal disease (ESRD).
Conclusion: In this series of TAK patients with RAI, long-term non-renal and renal outcomes were favourable. No patient experienced ESRD or died.