Background: Inhibition of the renin-angiotensin system is a widely accepted approach to treat immunoglobulin A (IgA) nephropathy, whereas the role of fish oils as a supplement is controversial. Tumor necrosis factor α (TNF-α) is considered to be involved in the pathophysiologic process of this disorder. Recent in vitro and clinical observations that wormwood can decrease TNF-α levels has led us to investigate the effect of wormwood as a supplement in patients with IgA nephropathy.
Study design: Pilot uncontrolled trial.
Setting & participants: 10 patients with biopsy-proven IgA nephropathy, normal kidney function, and a history of at least 3 months of proteinuria with protein excretion > 500 mg/d and < 3,500 mg/d despite ongoing dual renin-angiotensin system blockade.
Intervention: The selected patients were given supplements of 1.8 g/d of thujone-free wormwood preparation for 6 months without discontinuing their renin-angiotensin system blockade.
Outcomes: Proteinuria and blood pressure after intervention compared with baseline values.
Measurements: Monthly assessment of urine protein-creatinine ratio and blood pressure during the observation period.
Results: Urine protein-creatinine ratio decreased significantly from 2,340 ± 530 to 315 ± 200 mg/g at the end of the supplementation period (P < 0.001) and was stable during the supplement-free follow-up of another 6 months. Estimated glomerular filtration rate and endogenous creatinine clearance were unchanged during the entire study period. There was a moderate, but significant, decrease (P < 0.002) in mean arterial blood pressure.
Limitations: Open uncontrolled trial including a small number of patients.
Conclusions: Thujone-free wormwood with its favorable safety profile can be an alternative supplement to manage proteinuria in patients with IgA nephropathy.
Trial registration: ClinicalTrials.gov NCT01126931.
Copyright © 2010 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.