Home monitoring of maintenance intravenous immunoglobulin therapy in patients with chronic inflammatory neuropathy

Abstract

To evaluate the utility of different outcome measures to monitor dose adjustment of intravenous immunoglobulin (IVIg) therapy in patients with chronic inflammatory neuropathy (CIN). We assessed the adjustment of IVIg maintenance therapy in 20 patients (10 CIDP and 10 MMN) by regularly monitoring grip strength (GS) using a Martin Vigorimeter, RODS, and quality of life using the SF‐36 questionnaire. These measures were regularly performed by the patient at home. We also assessed the extended MRC sumscore (eMRC sumscore) at each outpatient visit for IVIg infusion. We also enrolled 30 healthy controls to measure any possible training effect of GS with time and to analyze random fluctuation of GS. Clinically relevant change was detected by eMRC sumscore in 14 (93%) patients, by RODS in 11 (73%) patients, and by GS in 8 (53%) patients. Early sensitivity was greatest for RODS (73%), followed by GS (53%), and eMRC sumscore (27%). This differed from CIDP, with an early change in RODS in 100% of patients, and MMN with an early change in GS in 75%. None of the outcome measures alone was sufficient to detect clinically significant changes in all patients. Home monitoring of outcome measures objectively assisted clinical decision during individualization of IVIg treatment. We recommend a multimodal approach using different outcome measures to monitor the individual patient with CIN.

European Academy of Neurology/Peripheral Nerve Society guideline on diagnosis and treatment of chronic inflammatory demyelinating polyradiculoneuropathy: Report of a joint Task Force—Second revision

“…Some examples of disability and impairment scales are given: Disability can be assessed by the Inflammatory Rasch‐built Overall Disability Scale (I‐RODS) 94–96 and the Inflammatory Neuropathy Cause and Treatment (INCAT) disability scale 97,98 Impairment can be assessed by the MRC sum score, 96,98,99 the Modified INCAT Sensory Sum scale (mISS), 98,100 the Neuropathy Impairment Score, 101 and by measuring grip strength using handheld dynamometry 98,102–104 The changes required to define improvement have not been adequately validated.…”

“…97,98 Impairment can be assessed by the MRC sum score, 96,98,99 the Modified INCAT Sensory Sum scale (mISS), 98,100 the Neuropathy Impairment Score, 101 and by measuring grip strength using handheld dynamometry. 98,[102][103][104] • The changes required to define improvement have not been ade- **values averaged over 3 consecutive days improve diagnostic specificity. 104 T A B L E 3 Sensory nerve conduction criteria (1) CIDP…”

European Academy of Neurology/Peripheral Nerve Society guideline on diagnosis and treatment of chronic inflammatory demyelinating polyradiculoneuropathy: Report of a joint Task Force—Second revision

“…Some examples of disability and impairment scales are given: ○Disability can be assessed by the Inflammatory Rasch‐built Overall Disability Scale (I‐RODS) [94–96] and the Inflammatory Neuropathy Cause and Treatment (INCAT) disability scale [97,98]. ○Impairment can be assessed by the MRC sum score [96,98,99], the Modified INCAT Sensory Sum scale (mISS) [98,100], the Neuropathy Impairment Score [101], and by measuring grip strength using handheld dynamometry [98,102–104]. The changes required to define improvement have not been adequately validated.…”

Clinical outcome of CIDP one year after start of treatment: a prospective cohort study

“…Our study used three different outcome measures along with MCID based cut-off values to define improvement. We recognize that these criteria do not always reflect clinical practice and that a less static, more patient-tailored assessment may be more suitable to define meaningful improvement and treatment (non) responders [47,[49][50][51]. We advocate a multimodal approach in those patients with expected limited improvement, for example in patients with severe axonal damage at presentation or those with only minimal disability or impairment, if treatment is considered justified at all.…”