The Oculobulbar Facial Respiratory score is a tool to assess bulbar function in myasthenia gravis patients

The Oculobulbar Facial Respiratory (OBFR) score is a tool that objectively measures bulbar function in myasthenia gravis (MG). In this study, we analyzed the relation between the OBFR and the MG Activities of Daily Living (MG-ADL) score, and also with the more recently described MG Composite and 15-item MG Quality-of-Life (MG-QOL15) scales. We recruited 42 patients from two centers and assessed them on two occasions, approximately 6 months apart, using the OBFR, MG Composite, MG-ADL, and MG-QOL15 scales. The 'modified' OBFR score was derived from the original OBFR score. The OBFR score correlated significantly with the MG Composite, MG-ADL, and MG-QOL15 scores for both assessments, and with the sum of the bulbar items for all three scores. It also correlated strongly with the individual bulbar-related items of all three scores. The 'modified' OBFR score also correlated significantly with all the aforementioned scores. This study confirmed construct validity of the OBFR and 'modified' OBFR scores.     

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     

Translation and validation of the 15‐item Myasthenia Gravis Quality of life scale in Dutch

Introduction: The 15‐item Myasthenia Gravis Quality of Life (MG‐QOL15) scale has been developed to assess the health‐related quality of life of patients with myasthenia gravis (MG). The aim of this study was to translate the original English version into Dutch and to test the test–retest reliability and construct validity. Methods: Fifty patients with MG were included. Test–retest reliability and internal consistency were assessed using the intraclass correlation coefficient (ICC) and the Cronbach α. Construct validity was assessed by testing 5 predefined hypotheses. Results: A good test–retest reliability was confirmed with an ICC of 0.866. The Cronbach α was 0.93. The predefined hypotheses were confirmed in 80% of cases, which points to good construct validity. Discussion: The Dutch MG‐QOL15 has good test–retest reliability and good construct validity. It can be used for research in a Dutch‐speaking population. It is also suitable for monitoring individual patients in clinical practice. Muscle Nerve 57 : 206–211, 2018     

The utility of a single simple question in the evaluation of patients with myasthenia gravis

Introduction: Assessing myasthenia gravis (MG) can be challenging, and multiple scales are available to evaluate disease severity. We evaluated the utility of a single, simple question, as part of the MG evaluation: “What percentage of normal do you feel regarding your MG, 0%–100% normal?” Methods: A retrospective chart review of patients attending the neuromuscular clinic from January 2014 to December 2015 was performed. Responses were correlated with symptoms and signs, the Quantitative Myasthenia Gravis Score (QMGS), the Myasthenia Gravis Impairment Index (MGII), and the 15‐item Myasthenia Gravis Quality of Life scale (MG‐QOL15). Results: The total cohort included 169 patients. The percentage of normal correlated strongly with limb muscle weakness and MG scales, moderately with bulbar and respiratory symptoms, and weakly with ocular manifestations. Discussion: The question, “What percentage of normal do you feel regarding your MG?” is feasible and valid, and can be incorporated easily into routine clinical evaluation. Muscle Nerve 57 : 240–244, 2018     

The modified rankin scale to assess disability in myasthenia gravis: Comparing with other tools

Introduction: We explored the modified Rankin scale (mRS) as a tool to quantitate disability in myasthenia gravis (MG). Our aim was to correlate patients' perception of their disability with that of the care provider and determine its relationship with other MG‐related scores. Methods: We evaluated 107 MG patients at 2 neurological centers. Patients were assessed over the telephone before and after clinic visits using the 15‐item Myasthenia Gravis Quality‐of‐Life index (MG‐QOL15) and mRS. At the clinic, patients were assessed using the MG‐QOL15, MG Composite (MGC), and mRS. Results: The MG‐QOL15 correlated with the MGC, mRS, and assessors' scores of patients. Assessors' perception of disease burden was in line with that of the patients' scoring. MG‐QOL15 scores obtained over the telephone were consistent with those obtained in the clinic. Scores were generally higher in patients receiving steroids at >5 mg/day and in those receiving or seeking benefits. Conclusion: The MG‐QOL15 and mRS are useful for estimating disability in MG. Muscle Nerve 50 : 501–507, 2014     

Construct and concurrent validation of the MG‐QOL15 in the practice setting

Health‐related quality of life (HRQOL) estimates can play an important role in patient care by providing information about the patient's perception of impairment and disability and the degree to which the patient tolerates disease manifestations. The 15‐item myasthenia gravis quality of life scale (MG‐QOL15) is an HRQOL evaluative instrument specific to patients with myasthenia gravis (MG) that was designed to be easy to administer and interpret. In this multicenter study we demonstrate the construct validity of the MG‐QOL15 in the practice setting. To assess the construct validity, score distributions were examined for test items in different MG patient groups that represent the clinical spectrum of the disease. For example, patients in remission more frequently scored test items as normal than did patients in other groups. Patients with lower (better) MG composite scores also more frequently scored items as normal than did patients with higher (worse) scores. There was also appropriate correlation between the MG‐QOL15 and the other MG‐specific scales studied. The study findings shed light on what troubles MG patients. The MG‐QOL15 has construct validity in the clinical practice setting and represents an efficient and valuable tool for assessing HRQOL for patients with MG. Muscle Nerve, 2010     

Construction of an efficient evaluative instrument for Myasthenia Gravis: The MG composite

We assessed the performance of items from the Quantitative Myasthenia Gravis (QMG), MMT (Manual Muscle Test), and MG‐ADL (Myasthenia Gravis – Activities of Daily Living) scales, using data from two recently completed treatment trials of generalized MG. Items were selected that were relevant to manifestations of MG, meaningful to both the physician and the patient, and responsive to clinical change. After the 10 items were chosen, they were weighted based on input from MG experts from around the world, considering factors such as quality of life, disease severity, risk, prognosis, validity, and reliability. The MG Composite is easy to administer, takes less than 5 minutes to complete, and requires no equipment. Weighting of the response options of the 10 items should result in ordinal scores that better represent MG status and are more responsive to meaningful clinical change. To better determine its suitability for clinical use and for treatment trials, the MG Composite will be tested prospectively at several academic medical centers and will be used as a secondary measure of efficacy in pending clinical trials of MG. Muscle Nerve 38: 1553–1562, 2008     

The MG-QOL15 for following the health-related quality of life of patients with myasthenia gravis

The MG-QOL15 is helpful in informing the clinician about the patient's perception of the extent of and dissatisfaction with myasthenia gravis (MG)-related dysfunction. The aims of this study were to determine the usefulness of the MG-QOL15 for following individuals with MG and to guide clinical researchers who plan to use the MG-QOL15. We assessed sensitivity and specificity for detecting clinical change and evaluated test-retest reliability. Sensitivities and specificities of various cut-points of change in scores are presented. Also presented are means and standard deviations of MG-QOL15 scores for all patients and for subgroups of patients. The test-retest reliability coefficient was 98.6%. The MG-QOL15 has an acceptable longitudinal construct validity. We consider this instrument to be most useful for informing the clinician about the patient's perception and tolerance of MG-related dysfunction. More objective measures, such as the MG Composite, should also be used to follow disease severity.     

Surrogate therapeutic outcome measures in patients with myasthenia gravis

Treatment of acquired myasthenia gravis (MG) with immunotherapies successfully relieves symptoms and improves strength as documented by the Quantitative Myasthenia Gravis Score for disease severity (QMGS). Neuromuscular function, as demonstrated by the surrogate measures of repetitive nerve stimulation (RNS) and single-fiber electromyography (SFEMG), is sensitive for diagnosis and staging disease severity. This study of 51 patients treated with immunomodulation confirmed that RNS and SFEMG are useful to stage disease severity, but found that clinical measures such as the QMGS are more sensitive to change than electrophysiological parameters. The presence of blocking on SFEMG did predict responsiveness to intravenous immunoglobulin (IVIG) treatment, providing clinicians with an objective, reliable, quantitative measure to help determine which patients will benefit from this costly treatment.     

Myasthenic crisis patients who require intensive care unit management

The purpose of this report was to investigate predictive factors that necessitate intensive care in myasthenic crisis (MC). We retrospectively reviewed MC patients at our institution and compared ICU and ward management groups. Higher MG-ADL scale scores, non-ocular initial symptoms, infection-triggered findings, and higher MGFA classification were observed more frequently in the ICU group. In patients with these prognostic factors, better outcomes may be obtained with early institution of intensive care. Muscle Nerve 46: 440-442, 2012.     

Myasthenia gravis in children: a longitudinal study

BACKGROUND: Juvenile myasthenia gravis (JMG) is an uncommon disease. Unlike adults, clinical characteristics and outcomes of myasthenia gravis (MG) are not well studied in children. PATIENTS AND METHODS: Case records of 77 patients with MG who were 15 years of age or less at disease onset, evaluated over a period of 34 years at the National Institute of Mental Health and Neurosciences, Bangalore, India, were reviewed. Their clinical characteristics and response to therapy was compared with 290 patients with MG onset after 15 years of age. RESULTS: Median age at onset was 8 years and mean period of follow-up was 6.2 years (range 6 months to 25 years). At presentation, 30% of patients had ocular myasthenia and the rest had generalized disease. Twenty-one patients (27%) had disease confined to ocular muscles throughout the course and three had limb girdle myasthenia. Familial myasthenia was more common than adult onset disease, 10 patients had positive family history. Unlike adults, none of the patients had associated autoimmune disease. Fifty-two patients (67%) received corticosteroids, and azathioprine was added in five patients. Thymectomy was performed in 11 patients, six below the age of 15 years. Thymic histology was normal in one and showed hyperplasia in eight and thymoma in one. Four patients had crisis. At the end of follow-up, 25 patients were asymptomatic, 28 had partial improvement, and nine remained unchanged or worsened and two died. Ten patients achieved complete stable remission. CONCLUSIONS: This study shows some distinctive characteristics of JMG, such as higher frequency of ocular myasthenia, benign course, better long-term outcome and lack of association of thymoma and other autoimmune disorders.     

The role of life events in the myasthenia gravis outcome: a one-year longitudinal study

We examined 51 patients suffering from myasthenia gravis (MG) and studied the relevance of stressful life events in relation to the course of the disease. Life events were assessed by means of the Paykel's Interview for Recent Life Events. The stage severity of MG was assessed by means of the Osserman and Genkins scale, twice per patient, at one year intervals. Simultaneously, life events were assessed for the 12 months preceding each of the 2 assessments of MG. Over the 2 MG evaluations 16 patients improved, 6 worsened and in 29 no change took place. Using life events data collected at the first interview, and applying a prospective design, no difference was found between patients who improved and those who remained unchanged or worsened. Life events reported at the second interview, as having occurred during the inter-assessment year, and collected according to a retrospective design, were significantly fewer in improvers than in non-improvers.     

Fatigue is a relevant outcome in patients with myasthenia gravis

Introduction: Patients with myasthenia gravis often experience fatigue, but its effect on quality of life (QoL) is underestimated, and fatigue is rarely measured in clinical trials. Methods: Two hundred fifty‐seven myasthenic patients completed the Neuro‐QoL‐Fatigue and measures of disease severity and QoL. We studied the relationship between fatigue and clinical and demographic variables. Finally, we studied the responsiveness of the Neuro‐QoL‐Fatigue in 95 patients receiving treatments for myasthenia and estimated the minimal important difference (MID). Results: Fatigue correlated with greater disease severity (r = 0.52–0.69, P < 0.0001) and worse QoL (r = 0.65–0.75, P < 0.0001). Patients in remission, with minimal manifestations, and pure ocular symptoms reported minimal fatigue. Regression modeling showed that, in addition to its relationship with disease severity, fatigue was worse in females, patients with generalized disease, and those with anxiety/depression. Fatigue improved after immunomodulation (P < 0.0001), and the MID was 5.3 points. Discussion: Fatigue in myasthenia correlates with disease severity, affects QoL, and can improve after treatment. Muscle Nerve 58 : 197–203, 2018     

Long-term safety and efficacy of eculizumab in generalized myasthenia gravis

Introduction: Eculizumab is effective and well tolerated in patients with antiacetylcholine receptor antibody-positive refractory generalized myasthenia gravis (gMG; REGAIN; NCT01997229). We report an interim analysis of an open-label extension of REGAIN, evaluating eculizumab's long-term safety and efficacy. Methods: Eculizumab (1,200 mg every 2 weeks for 22.7 months [median]) was administered to 117 patients. Results: The safety profile of eculizumab was consistent with REGAIN; no cases of meningococcal infection were reported during the interim analysis period. Myasthenia gravis exacerbation rate was reduced by 75% from the year before REGAIN (P < 0.0001). Improvements with eculizumab in activities of daily living, muscle strength, functional ability, and quality of life in REGAIN were maintained through 3 years; 56% of patients achieved minimal manifestations or pharmacological remission. Patients who had received placebo during REGAIN experienced rapid and sustained improvements during open-label eculizumab (P < 0.0001). Discussion: These findings provide evidence for the long-term safety and sustained efficacy of eculizumab for refractory gMG. Muscle Nerve 2019