Neurology April 2009 Volume 72 Issue 15

Objective: Idiopathic REM sleep behavior disorder (RBD) is a potential preclinical marker for the development of neurodegenerative diseases, particularly Parkinson disease (PD) and Lewy body dementia. However, the long-term risk of developing neurodegeneration in patients with idiopathic RBD has not been established. Obtaining an accurate picture of this risk is essential for counseling patients and for development of potential neuroprotective therapies.Methods: We conducted a follow-up study of all patients seen at the sleep disorders laboratory at the Hopital du Sacre Coeur with a diagnosis of idiopathic RBD. Diagnoses of parkinsonism and dementia were defined according to standard criteria. Survival curves were constructed to estimate the 5-, 10-, and 12-year risk of developing neurodegenerative disease.Results: Of 113 patients, 93 (82%) met inclusion criteria. The mean age of participants was 65.4 years and 75 patients (80.4%) were men. Over the follow-up period, 26/93 patients developed a neurodegenerative disorder. A total of 14 patients developed PD, 7 developed Lewy body dementia, 4 developed dementia that met clinical criteria for AD, and 1 developed multiple system atrophy. The estimated 5-year risk of neurodegenerative disease was 17.7%, the 10-year risk was 40.6%, and the 12-year risk was 52.4%.Conclusions: Although we have found a slightly lower risk than other reports, the risk of developing neurodegenerative disease in idiopathic REM sleep behavior disorder is substantial, with the majority of patients developing Parkinson disease and Lewy body dementia.(C)2009AAN Enterprises, Inc.

Background: In acute stroke trials, functional outcome may be analyzed by dichotomizing ordinal outcome scales or by evaluating the entire scale range (shift analysis). The conditions under which shift or binary analysis will be more efficient have not been previously well delineated.Methods: Model randomized clinical trials employing the modified Rankin Scale of global handicap were constructed to reflect 1) mild benefits experienced across all ranges of stroke severity (neuroprotective effect), 2) substantial benefits across all ranges of stroke severity (early recanalization effect), 3) substantial benefits across wide range of stroke severity but with limited ability to achieve fully normal outcome (late recanalization effect), 4) benefits clustered at unexpected health state transitions.Results: In neuroprotective models, shift analysis was the most efficient technique in detecting a treatment effect. In the early recanalization models, dichotomization at excellent outcome and shift analysis were of comparable efficiency, both superior to dichotomization at good outcome. In the late recanalization models, dichotomization at good outcome performed best, shift analysis less well, and dichotomization at excellent outcome poorly. In the unexpected benefits model, shift analysis substantially outperformed dichotomization analyses. These patterns held among the seven actual acute trials reporting full range Rankin outcomes and showing treatment benefit identified in the literature.Conclusions: The pattern of treatment effect of the intervention determines whether shift analysis or simple dichotomized analysis will be more efficient. Shift analysis is especially advantageous when treatments confer a relatively uniform, mild benefit to patients over a wide range of stroke severities or confer benefits at unexpected but clinically important health state transitions.(C)2009AAN Enterprises, Inc.

Objective: Axonal degeneration is the likely cause of disease progression in multiple sclerosis (MS). Our previous results indicated that neuron-specific N-acetylaspartate (NAA) is a candidate CSF biomarker for disease progression in MS. The aim of this study was to explore the potential of NAA as an early biomarker of axonal damage in MS. Next, we wanted to know the additional value of measurement of NAA compared to other candidate markers for axonal damage, such as neurofilament subunits and tau protein.Methods: Levels of NAA, neurofilament light, neurofilament heavy, and tau were determined in CSF of patients with clinically isolated syndrome (CIS, n = 38), relapsing-remitting MS (RRMS, n = 42), secondary progressive MS (SPMS, n = 28), and primary progressive MS (PPMS, n = 6); patients without neurologic disease (ND, n = 28); noninflammatory neurologic controls (n = 18); and inflammatory neurologic controls (n = 39).Results: CSF NAA levels were decreased in patients with SPMS compared to ND controls, patients with CIS, and patients with RRMS. CSF NAA levels in patients with CIS and RRMS were similar to those in ND subjects. All axonal damage proteins showed specific patterns of changes and relations with disease activity measures. The neurofilament light chain levels were already increased in patients with CIS, especially in patients who converted to MS. The neurofilament heavy chain levels were highest in the patients with SPMS. Tau levels were similar in MS and ND.Conclusions: CSF N-acetylaspartate (NAA) levels were not different from patients without neurologic disease in early stages of multiple sclerosis, though decreased as the disease progressed. Combining CSF NAA and neurofilament levels yields information on different phases of axonal pathology.(C)2009AAN Enterprises, Inc.

Background: Chronic inflammatory demyelinating polyradiculoneuropathy trials have demonstrated the efficacy of IV immunoglobulin vs placebo. However, these trails have not addressed the long-term impact on health-related quality of life (HRQoL).Methods: One hundred seventeen patients in a randomized, double-blind, response-conditional crossover trial received immune globulin IV, 10% caprylate/chromatography purified (IGIV-C [Gamunex(R)]), or placebo every 3 weeks for up to 24 weeks in the first period (FP). Participants whose inflammatory neuropathy cause and treatment disability score did not improve by >=1 point received alternate treatment in a 24-week crossover period (CP). In either period, participants who improved and completed treatment were eligible to be randomly reassigned to a blinded 24-week extension phase (EP). HRQoL analyses were conducted using the Short Form-36(R) (SF-36) and the Rotterdam Handicap Scale (RHS).Results: In the FP, greater improvements in both SF-36 physical and mental component scores were observed with IGIV-C vs placebo, with a significant improvement in the physical component score (difference 4.4 points; 95% confidence interval [CI] 0.7-8.0). Improvements in all SF-36 domains favored IGIV-C vs placebo, with physical functioning, role-physical, social functioning, and mental health reaching significance. Participants receiving IGIV-C experienced a larger improvement in RHS vs those receiving placebo (difference 3.4 points; 95% CI 1.4-5.5; p = 0.001). In the CP, similar general trends were observed. In the EP, mean SF-36 improvements were generally improved or maintained in participants who continued IGIV-C therapy; however, worsening was observed in participants re-randomized to placebo.Conclusions: Long-term therapy with immune globulin IV, 10% caprylate/chromatography purified, improves and maintains health-related quality of life in chronic inflammatory demyelinating polyradiculoneuropathy.(C)2009AAN Enterprises, Inc.