Background: In adult-onset minimal-change disease (MCD) the predictors of remission and relapse of proteinuria and corticosteroid-related adverse events remain unknown.
Methods: The multicenter retrospective cohort study, the STudy of Outcomes and Practice patterns of Minimal-Change Disease (STOP-MCD), included 142 adult-onset MCD patients in 5 nephrology centers in Japan. Primary outcomes were first remission of proteinuria defined by urinary protein (UP) <0.3 g/day, UP/creatinine ratio (UPCR) <0.3, and/or negative/trace by dipstick test and first relapse of proteinuria defined by UP ≥1.0 g/day, UPCR ≥1.0, and/or dipstick test ≥1+ followed by immunosuppressive therapy. Secondary outcomes were corticosteroid-related adverse events.
Results: During the median 3.6 (interquartile range, 2.0-6.9) years of the entire observational period, 136 (95.8 %) and 79 (58.1 %) patients developed at least 1 remission and 1 recurrence within a median of 15 (10-34) days and 0.90 (0.55-1.57) years, respectively. Compared with younger patients aged 15-29 years at kidney biopsy, elderly patients aged ≥60 years developed remission significantly later [hazard ratio 0.53 (95 % confidence interval 0.32-0.88)], while older patients aged ≥45 years were at a significantly lower risk of relapse [45-59 years, 0.46 (0.22-0.96); 60-83 years, 0.39 (0.21-0.74)]. However, older patients were significantly more vulnerable to severe infection, diabetes, and cataract as compared with younger patients.
Conclusion: Younger patients had a higher risk of relapse while older patients had a lower risk of relapse but a higher risk of corticosteroid-related adverse events.