Predictors of relapses in patients with chronic inflammatory demyelinating polyneuropathy receiving subcutaneous immunoglobulin therapy - a post-hoc analysis.

BACKGROUND: In a previous study we demonstrated that standardized tapering off subcutaneous immunoglobulin (SCIG) is a safe way to identify remission in patients with chronic inflammatory demyelinating polyneuropathy (CIDP). However, clinical characteristics and dosage of SCIG in patients in remission are unknown. METHODS: week, pending no deterioration occurred. All patients were followed for 164 weeks after inclusion and were evaluated with disability scores, quality of life score (EQ-5D-5L), blood samples and clinical examination. RESULTS: Receiving a dosage of SCIG >25 g/week predicts a higher risk of relapse, OR 6.3 (95CI 1.8-20.2)(p = 0.004), but not when considering body weight (SCIG >0.3 g/kg/week), OR 3.3 (95CI 1.0-9.7)(p = 0.05). Moreover, a higher level of serum NfL OR 8.2 (95CI 1.1-93.3)(p = 0.04) predicts relapse. Low scores on EQ-5D-5L at baseline predicted increased risk of relapse. Serum calprotectin was similar in patients with relapse and in remission. Evaluating measurements from baseline, final visit and the last visit before final visit (LVBF), we found that deterioration in clinical performance could not be predicted at LVBF based on any of the tests performed. CONCLUSION: Patients experiencing a relapse of CIDP during tapering off SCIG seem to receive a total higher dosage of immunoglobulin and had a higher sNfL prior to tapering off compared to patients without a relapse.