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American Journal of Kidney Diseases

Induction and Maintenance Treatment of Proliferative Lupus Nephritis: A Meta-analysis of Randomized Controlled Trials

Published:November 26, 2012DOI:https://doi.org/10.1053/j.ajkd.2012.08.041

      Background

      Lupus nephritis accounts for ∼1% of patients starting dialysis therapy. Treatment regimens combining cyclophosphamide with steroids preserve kidney function but have significant side effects. Newer immunosuppressive agents may have improved toxicity profiles.

      Study Design

      Systematic review and random-effects meta-analysis, searching MEDLINE (1966 to April 2012), EMBASE (1988-2011), and the Cochrane Renal Group Specialised Register.

      Setting & Population

      Patients with biopsy-proven proliferative lupus nephritis (classes III, IV, V+III, and V+IV).

      Selection Criteria

      Randomized controlled trials.

      Intervention

      Immunosuppressive treatment regimens used for induction and maintenance therapy of lupus nephritis.

      Outcomes

      Mortality, renal remission and relapse, doubling of creatinine level, proteinuria, incidence of end-stage kidney disease, ovarian failure, alopecia, leukopenia, infections, diarrhea, vomiting, malignancy, and bladder toxicity.

      Results

      45 trials (2,559 participants) of induction therapy and 6 (514 participants) of maintenance therapy were included. In induction regimens comparing mycophenolate mofetil (MMF) with intravenous cyclophosphamide, there was no significant difference in mortality (7 studies, 710 patients; risk ratio [RR], 1.02; 95% CI, 0.52-1.98), incidence of end-stage kidney disease (3 studies, 231 patients; RR, 0.71; 95% CI, 0.27-1.84), complete renal remission (6 studies, 686 patients; RR, 1.39; 95% CI, 0.99-1.95), and renal relapse (1 study, 140 patients; RR, 0.97; 95% CI, 0.39-2.44). MMF-treated patients had significantly lower risks of ovarian failure (2 studies, 498 patients; RR, 0.15; 95% CI, 0.03-0.80) and alopecia (2 studies, 522 patients; RR, 0.22; 95% CI, 0.06-0.86). In maintenance therapy comparing azathioprine with MMF, the risk of renal relapse was significantly higher (3 studies, 371 patients; RR, 1.83; 95% CI, 1.24-2.71).

      Limitations

      Heterogeneity in interventions and definitions of remission and lack of long-term outcome reporting.

      Conclusions

      MMF is as effective as cyclophosphamide in achieving remission in lupus nephritis, but is safer, with a lower risk of ovarian failure. MMF is more effective than azathioprine in maintenance therapy for preventing relapse, with no difference in clinically important side effects.

      Index Words

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