Vera Bril

Limits of the sympathetic skin response in patients with diabetic polyneuropathy

We performed upper‐ and lower‐limb sympathetic skin responses (SSRs) in a series of 337 diabetic patients with and without peripheral polyneuropathy and 38 reference subjects. We did not find any correlations between SSRs and symptoms of pain or autonomic dysfunction. The SSR correlated more strongly with vibration perception threshold (VPT) and sural nerve amplitude than with cooling detection threshold (CDT) or clinical symptoms. We conclude that current limitations inherent in SSR testing preclude its use as a reliable and consistent index of the autonomic dysfunction commonly encountered in diabetic patients.

Changes in quality of life scores with intravenous immunoglobulin or plasmapheresis in patients with myasthenia gravis

Background Intravenous immunoglobulin (IVIG) and plasmapheresis (plasma exchange (PLEX)) have comparable efficacy in reducing the Quantitative Myasthenia Gravis Score for disease severity (QMGS) in patients with moderate to severe myasthenia gravis (MG). Objective To determine if the improvement in the quality of life (QOL) after immunomodulation is comparable with either IVIG or PLEX. Methods 62 patients participated in the MG-QOL-60 study, completing the questionnaire at baseline and at day 14 after treatment. The MG-QOL-15 scores were computed from the MG-QOL-60 questionnaire responses. We analysed the change in the QOL scores from baseline to day 14 in both treatment groups. Results The scores in both QOL scales decreased at day 14 in the IVIG and PLEX groups, without significant difference between groups (QOL-15: IVIG −5.7±8.5, PLEX: −7.0±7.6, p=0.52; QOL-60: IVIG −13.3±16.9, PLEX −18.5±22.0, p=0.41). The improvement in QOL showed a good correlation with the decrease in QMGS. There was an excellent correlation between the MG-QOL-15 and MG-QOL-60 scores at baseline and at day 14. Conclusions This study of MG-QOL changes supports recent findings that IVIG and PLEX are comparable in the treatment of patients with moderate to severe MG and worsening symptoms. Furthermore, our study supports the use of the MG-QOL-15 as a secondary outcome measure in future clinical trials in MG.

International clinimetric evaluation of the MG-QOL15, resulting in slight revision and subsequent validation of the MG-QOL15r.

Introduction: The MG‐QOL15 is a validated, health‐related quality of life (HRQOL) measure for myasthenia gravis (MG). Widespread use of the scale gave us the opportunity to further analyze its clinimetric properties. Methods: We first performed Rasch analysis on >1,300 15‐item Myasthenia Gravis Quality of Life scale (MG‐QOL15) completed surveys. Results were discussed during a conference call with specialists and biostatisticians. We decided to revise 3 items and prospectively evaluate the revised scale (MG‐QOL15r) using either 3, 4, or 5 responses. Rasch analysis was then performed on >1,300 MG‐QOL15r scales. Results: The MGQOL15r performed slightly better than the MG‐QOL15. The 3‐response option MG‐QOL15r demonstrated better clinimetric properties than the 4‐ or 5‐option scales. Relative distributions of item and person location estimates showed good coverage of disease severity. Conclusions: The MG‐QOL15r is now the preferred HRQOL instrument for MG because of improved clinimetrics and ease of use. This revision does not negate previous studies or interpretations of results using the MG‐QOL15. Muscle Nerve 54: 1015–1022, 2016

Follow-up nerve conduction studies in CIDP after treatment with IGIV-C: Comparison of patients with and without subsequent relapse.

Introduction: Electrodiagnostic studies (EDX) are not performed routinely before treatment suspension in CIDP, and no data exist regarding their value in predicting clinical relapse. Methods: Serial EDX (baseline and after IGIV‐C therapy) were analyzed from subjects in the ICE clinical trial who responded to IGIV‐C treatment and were subsequently re‐randomized to placebo in an extension phase. Comparisons were made between subjects who relapsed and those who did not. Results: A total of 55% (6/11) of the Relapse group had an increase in total number of demyelinating findings (DF) versus 8% (1/13) in the No Relapse group (Pu2009=u20090.023). In the Relapse group, 100% had ≥1 new DF and 73% (8/11) had ≥4 new DF versus 60% (8/13) and 8% (1/13), respectively, in the No Relapse group. Conclusions: An increased total number of DF or the occurrence of ≥4 new DF may indicate a higher risk of clinical relapse after treatment cessation in IGIV‐C‐responsive patients. Muscle Nerve 52: 498–502, 2015

Using in vivo corneal confocal microscopy to identify diabetic sensorimotor polyneuropathy risk profiles in patients with type 1 diabetes

Objective Diabetic sensorimotor peripheral neuropathy (DSP) is the most prevalent complication in diabetes mellitus. Identifying DSP risk is essential for intervening early in the natural history of the disease. Small nerve fibers are affected earliest in the disease progression and evidence of this damage can be identified using in vivo corneal confocal microscopy (IVCCM). Research design and methods We applied IVCCM to a cohort of 40 patients with type 1 diabetes to identify their DSP risk profile. We measured standard IVCCM parameters including corneal nerve fiber length (CNFL), and performed nerve conduction studies and quantitative sensory testing. Results 40 patients (53% female), with a mean age of 48±14, BMI 28.1±5.8, and diabetes duration of 27±18u2005years were enrolled between March 2014 and June 2015. Mean IVCCM CNFL was 12.0±5.2u2005mm/mm2 (normal ≥15u2005mm/mm2). Ten patients (26%) without DSP were identified as being at risk of future DSP with mean CNFL 11.0±2.1u2005mm/mm2. Six patients (15%) were at low risk of future DSP with mean CNFL 19.0±4.6u2005mm/mm2, while 23 (59%) had established DSP with mean CNFL 10.5±4.5u2005mm/mm2. Conclusions IVCCM can be used successfully to identify the risk profile for DSP in patients with type 1 diabetes. This methodology may prove useful to classify patients for DSP intervention clinical trials.