A second brain death examination in patients older than 1 year is largely unecessary and may negatively affect organ donation, according to a report in the January 11 online Neurology. “In practice, observation time to a second neurologic examination was three times longer than the proposed guideline and associated with substantial intensive care unit costs and loss of viable organs,” researchers stated. The investigators reviewed data for 1,229 adult and 82 pediatric patients who had been pronounced brain-dead. No patients who were declared brain-dead regained brainstem function after repeat examination. The mean brain death declaration interval between the two examinations was 19.2 hours. Consent for organ donation decreased from 57% to 45% as the brain death declaration interval increased. However, refusal of organ donation increased from 23% to 36% as the brain death interval increased. A total of 166 patients (12%) sustained a cardiac arrest between the two examinations or after the second examination.
Most antiepileptic drugs (AEDs) were associated with an increased risk of nontraumatic fractures in patients 50 and older, according to a study in the January Archives of Neurology. A total of 15,792 persons with nontraumatic fractures of the wrist, hip, and vertebra were analyzed. Each patient was matched for age, sex, ethnicity, and comorbidity with as many as three controls (n = 47,289). Prior AED use among participants included carbamazepine, clonazepam, ethosuximide, felbamate, gabapentin, lamotrigine, levetiracetam, oxcarbazepine, phenobarbital, phenytoin, pregabalin, primidone, topiramate, valproic acid, and vigabatrin. The researchers found a significant increase in fracture risk for most of the AEDs (carbamazepine, clonazepam, gabapentin, phenobarbital, and phenytoin). The adjusted odds ratios (ORs) ranged from 1.24 for clonazepam use to 1.91 for phenytoin use. Valproic acid (adjusted OR, 1.10) was the only AED not associated with an increased fracture risk. “Further studies are warranted to assess the risk of nontraumatic fractures with the newer AEDs and to determine the efficacy of osteoprotective medications in this population,” the researchers stated.
Although some pediatric patients with multiple sclerosis (MS) refractory to initial treatment may effectively switch between first-line disease-modifying therapies (DMTs), some may require second-line therapeutic interventions, per a report in the December 13, 2010, online Archives of Neurology. Researchers reviewed the records of 258 children with a confirmed diagnosis of MS and who had taken DMTs. Interferon beta and glatiramer acetate were the two most frequently used first-line DMTs. Overall, 144 children (55.8%) continued to receive one therapy, while 65 (25.2%) received two sequential therapies, 29 (11.2%) received three therapies, and 20 (7.8%) received four or more therapies during a mean observation period of 3.9 years. “Second-line DMT use was restricted to interferon beta and glatiramer acetate in 203 children (78.7%), whereas other treatments such as broad-spectrum chemotherapies (cyclophosphamide, mitoxantrone hydrochloride), natalizumab, corticosteroids (monthly), and daclizumab were used at some point during the observation period for disease management in 55 children (21.3%),” stated the investigators.
Transient pregnancy restless legs syndrome is a significant risk factor for developing a future chronic idiopathic restless legs syndrome form, and for a new transient symptomatology in a future pregnancy, according to a study in the December 7, 2010, Neurology. Seventy-four women who experienced restless legs syndrome during a previous pregnancy, and 133 who did not, were included in the study. The incidence of restless legs syndrome was 56% person/year in women who experienced the transient pregnancy restless legs syndrome form, versus 12.6% person/year in women who did not, with a significant fourfold increased risk of developing chronic restless legs syndrome in women who presented with restless legs syndrome in their previous pregnancy. “Considering further new pregnancies during the follow-up period, restless legs symptoms reappeared in 58% of the cases, while they emerged for the first time in only 3% of women who had never experienced restless legs syndrome,” stated the authors.
The cancer drug paclitaxel may promote the regeneration of injured nerve cells in the CNS after spinal cord injury, according to a study in the online January 27 Science. Researchers found that the drug has a dual role in spinal cord repair in rodents, stabilizing the microtuble so that injured nerve cells regain their ability to grow and preventing the production of inhibitory substances in the scar tissue. Moderate microtubule stabilization decreased scar formation via various cellular mechanisms, including dampening of transforming growth factor-β signaling. “It prevented accumulation of chondroitin sulfate proteoglycans and rendered the lesion site permissive for axon regeneration of growth competent sensory neurons,” stated the investigators. “Microtubule stabilization also promoted growth of CNS axons of the Raphe-spinal tract and led to functional improvement.”