OBJECTIVE: To evaluate the 10-year therapeutic efficacy of Traditional Chinese Medicine (TCM) using the Strengthening Spleen and Draining Dampness therapy in the management of idiopathic membranous nephropathy (IMN).

METHODS: A single-center, retrospective analysis was conducted on patients diagnosed with IMN who met predefined inclusion and exclusion criteria. Data were collected from the Department of Nephrology at Longhua Hospital, affiliated with Shanghai University of Traditional Chinese Medicine, between January 2007 and December 2011. Clinical parameters including 24-h urinary protein, serum albumin, serum creatinine, and estimated glomerular filtration rate (eGFR, EPI) were assessed at baseline and at 1, 3, 5, and 10 years of follow-up. The efficacy of the Strengthening Spleen and Draining Dampness therapy was analyzed using repeated measures analysis of variance (ANOVA). Kaplan-Meier survival curves and multivariate proportional hazards model (Cox regression models) were employed to identify factors associated with treatment outcomes.

RESULTS: A total of 265 patients were included, with a median follow-up duration of 96 months (36, 122). TCM treatment significantly reduced 24-h urinary protein levels (P < 0.001), and increased serum albumin levels (P < 0.001), while serum creatinine remained stable (P = 0.187). Remission rates at 1, 3, 5, and 10 years were 52.81%, 69.71%, 68.39%, and 72.36%, respectively, and the rates of avoiding composite outcome events at the same intervals were 98.27%, 94.29%, 94.19%, and 93.50%. In the subgroup receiving TCM only, remission rates were 56.67%, 84.44%, 76.32%, and 82.86%. For patients treated initially with Western Medicine followed by TCM, the rates were 52.83%, 65.85%, 67.47% and 67.75%. In the cohort of patients who received TCM as their first-line therapy, remission rates were 49.23%, 62.50%, 61.76%, and 69.23%. Multivariate Cox regression analysis revealed that the duration of TCM treatment [hazard ratio (HR) = 0.826, 95% confidence interval (CI) (0.779, 0.876), P < 0.001], presence of hypertension [HR = 1.912, 95% CI (1.181, 3.094), P = 0.008], baseline serum albumin level [HR = 0.930, 95% CI (0.894, 0.969), P < 0.001], and the rate of serum albumin increase within the first year of treatment [HR = 0.930, 95% CI (0.909, 0.957), P < 0.001] were significantly associated with clinical outcomes.

CONCLUSION: The Strengthening Spleen and Draining Dampness therapy demonstrated robust short- and long-term efficacy in treating IMN, with high rates of remission and renal survival over 10 years. Key factors influencing clinical remission included the duration of TCM treatment, baseline serum albumin levels, the presence of hypertension, and the rate of increase in serum albumin within the first year. These findings suggest that this TCM approach provides a viable long-term treatment option for IMN.