Incidence and associated factors of dialysis discontinuation in patients with malignant hypertension-associated renal thrombotic microangiopathy: a multicenter cohort study

Patients with malignant hypertension (mHTN)-associated renal thrombotic microangiopathy (TMA) often present with progressive renal dysfunction, and some require dialysis at the time of diagnosis. Previous evidence has suggested that some patients may discontinue dialysis during follow-up after intensive antihypertensive therapy. However, the incidence of dialysis discontinuation and its associated factors remain unclear. This study aimed to investigate the incidence and associated factors of dialysis discontinuation in patients with mHTN-associated renal TMA who required dialysis at baseline. 132 patients with biopsy-proven mHTN-associated renal TMA who were dialysis-dependent at baseline were enrolled in this study. Patients were categorized into the dialysis discontinuation group (Group 1) and the dialysis-dependent group (Group 2). Cox regression analysis was performed to identify factors associated with dialysis discontinuation. Among the 132 patients, 50 (37.9%) patients achieved dialysis discontinuation, while 82 (62.1%) remained dialysis-dependent. The cumulative probabilities of dialysis discontinuation at 1, 3, 6, and 12 months of follow-up were 13.9%, 22.0%, 27.4%, and 31.5%, respectively. The median dialysis-free duration among patients who discontinued dialysis was 29.7 months. By multivariable Cox regression analysis, higher platelet counts (adjusted HR = 1.05, P = 0.003), lower maximum serum creatinine at baseline (adjusted HR = 0.88, P = 0.002), and a lower proportion of global glomerulosclerosis (adjusted HR = 0.78, P < 0.001) were independently associated with dialysis discontinuation. In patients with mHTN-associated renal TMA requiring dialysis, higher platelet counts, lower maximum serum creatinine at baseline, and a lower proportion of global glomerulosclerosis were independently associated with dialysis discontinuation.