Real life retrospective study of cannabidiol therapy in alternating hemiplegia of childhood.

BACKGROUND: Many alternating hemiplegia of childhood (AHC) patients have received Cannabidiol (CBD) but, to our knowledge, there are no published data available. GOALS: Test the hypothesis that CBD has favorable effects on AHC spells. METHODS: Retrospective review of available data of AHC patients who received CBD. Primary analysis: Clinical Global Impression Scale of Improvement (CGI-I) score for response of AHC spells to CBD with calculation of 95% confidence interval (CI) for rejection of the null hypothesis. Secondary analyses, performed to achieve an understanding of the effect of CBD as compared to flunarizine, were CGI-I scores of 1) epileptic seizures to CBD, 2) AHC spells to flunarizine, 3) epileptic seizures to flunarizine. Also, Mann-Whitney test was done for comparison of CGI-I scores of CBD and flunarizine to both AHC spells and seizures. RESULTS: We studied 16 AHC patients seen at Duke University and University of Lyon. CI of CGI-I scores for AHC spells in response to CBD and to flunarizine, each separately, indicated a positive response to each of these two medications: neither overlapped with the null hypothesis score, 4, indicating significant positive responses with p < 0.05 for both. These two scores also did not differ (p = 0.84) suggesting similar efficacy of both: CBD score was 2 ± 1.1 with a 95% CI of 1.5-2.6 and flunarizine score was 2.3 ± 1.3 with a 95% CI of 1.7-3.1. In patients who had seizures, CI calculations indicated a positive effect of CBD on seizure CGI scores but not of flunarizine on seizure scores. CBD was well tolerated with no patients discontinuing it due to side effects and with some reporting positive behavioral changes. CONCLUSION: Our study indicates a real-life positive effect of CBD on AHC type spells.

Characteristics of non-sleep related apneas in children with alternating hemiplegia of childhood.

BACKGROUND: Non-sleep related apnea (NSA) has been observed in alternating hemiplegia of childhood (AHC) but has yet to be characterized. GOALS: Investigate the following hypotheses: 1) AHC patients manifest NSA that is often severe. 2) NSA is usually triggered by precipitating events. 3) NSA is more likely in patients with ATP1A3 mutations. METHODS: Retrospective review of 51 consecutive AHC patients (ages 2-45 years) enrolled in our AHC registry. NSAs were classified as mild (not needing intervention), moderate (needing intervention but not perceived as life threatening), or severe (needing intervention and perceived as life threatening). RESULTS: 19/51 patients (37 %) had 52 NSA events (6 mild, 11 moderate, 35 severe). Mean age of onset of NSA (± Standard Error of the Mean (SEM)): 3.8 ± 1.5 (range 0-24) years, frequency during follow up was higher at younger ages as compared to adulthood (year 1: 2.2/year, adulthood: 0.060/year). NSAs were associated with triggering factors, bradycardia and with younger age (p < 0.008 in all) but not with mutation status (p = 0.360). Triggers, observed in 17 patients, most commonly included epileptic seizures in 9 (47 %), anesthesia, AHC spells and intercurrent, stressful, conditions. Management included use of pulse oximeter at home in nine patients, home oxygen in seven, intubation/ventilatory support in seven, and basic CPR in six. An additional patient required tracheostomy. There were no deaths or permanent sequalae. CONCLUSIONS: AHC patients experience NSAs that are often severe. These events are usually triggered by seizures or other stressful events and can be successfully managed with interventions tailored to the severity of the NSA.

Development and testing of methods to record and follow up spells in patients with alternating hemiplegia of childhood.

BACKGROUND: Developing methods to record Alternating Hemiplegia of Childhood (AHC) spells is essential for clinical trials and patient care. OBJECTIVES: Test the following hypotheses: 1) Video-library training improves participants' ability to correctly identify AHC spells. 2) A custom-designed event-calendar with weekly reviews results in consistent documentation of such events over time. 3) Use of an electronic diary (e-Diary) to register events is a useful tool. METHODS: 1) A video-library of AHC type spells was developed along with specific training; the effect of the training was tested in 36 caregivers. 2) An event-calendar was similarly developed and provided to 5 caregivers with weekly videoconference meetings for 8 weeks. 3) An e-Diary was developed and offered to 33 patients; time of usage and caregivers' feedback (telephone interview) were analyzed. RESULTS: 1) Video-library training: Wilcoxon test showed improvement in caregiver identification of spells (p = 0.047), Cohen's Kappa demonstrated high degree of agreement between caregivers'-experts' classifications (>0.9). 2) Event-calendar: 96.42% of entries had complete information; this did not change during follow up (p = 0.804). 3) e-Diary: whereas 52% of respondents used the e-Diary when offered (duration: 10.5 ± 8.1 months), 96.3% indicated they would use it in future studies. Those who used it for 13 months, were very likely to use it during the rest of that year. CONCLUSIONS: Video-library training improved spell identification. Calendar with weekly reviews resulted in a sustained and consistent record keeping. Caregivers' e-Diary feedback was encouraging with long-term usage in many. These approaches could be helpful for AHC and, potentially, in similar disorders.

Characterization of sedation and anesthesia complications in patients with alternating hemiplegia of childhood.

BACKGROUND: Alternating hemiplegia of childhood (AHC) pathophysiology suggests predisposition to sedation and anesthesia complications. GOALS: Hypotheses: 1) AHC patients experience high rates of sedation-anesthesia complications. 2) ATP1A3 mutation genotype positivity, age, and AHC severity correlate with more severe complications. 3) Prior short QTc correlates with cardiac rhythm complications. METHODS: Analysis of 34 consecutive AHC patients who underwent sedation or anesthesia. Classification of complications: mild (not requiring intervention), moderate (intervention), severe (intervention, risk for permanent injury or potential life-threatening emergency). STATISTICS: Fisher Exact test, Spearman correlations. RESULTS: These patients underwent 129 procedures (3.79 ± 2.75 procedures/patient). Twelve (35%) experienced complications during at least one procedure. Fourteen/129 procedures (11%) manifested one or more complications (2.3% mild, 7% moderate, 1.6% severe). Of the total 20 observed complications, six (33.3%) were severe: apneas (2), seizures (2), bradycardia (1), ventricular fibrillation that responded to resuscitation (1). Moderate complications: non-life-threatening bradycardias, apneas, AHC spells or seizures. Complications occurred during sedation or anesthesia and during procedures or recovery periods. Patients with disease-associated ATP1A3 variants were more likely to have moderate or severe complications. There was no correlation between complications and age or AHC severity. Presence of prior short QTc correlated with cardiac rhythm complications. After this series was analyzed, another patient had severe recurrent laryngeal dystonia requiring tracheostomy following anesthesia with intubation. CONCLUSIONS: During sedation or anesthesia, AHC patients, particularly those with ATP1A3 variants and prior short QTc, are at risk for complications consistent with AHC pathophysiology. Increased awareness is warranted during planning, performance, and recovery from such procedures.

Social impairments in alternating hemiplegia of childhood.

AIM: To evaluate presence and severity of social impairments in alternating hemiplegia of childhood (AHC) and determine factors that are associated with social impairments. METHOD: This was a retrospective analysis of 34 consecutive patients with AHC (19 females, 15 males; mean age: 9y 7mo, SD 8y 2mo, range 2y 7mo-40y), evaluated with the Social Responsiveness Scale, Second Edition (SRS-2). RESULTS: SRS-2 scores, indicating level of social impairment, were higher than population means (75, SD 14 vs 50, SD 10, p<0.001). Of these, 27 out of 34 had high scores: 23 severe (>76), four moderate (66-76). All subscale domains, including social cognition, social communication, social awareness, social motivation, restricted interests, and repetitive behavior, had abnormal scores compared to population means (p<0.001). High SRS-2 scores were associated with the presence of autism spectrum disorder (ASD) and epilepsy (p=0.01, p=0.04), but not with other scales of AHC disease symptomatology. All nine patients who received formal evaluations for ASD, because they had high SRS-2 scores, were diagnosed with ASD. INTERPRETATION: Most patients with AHC have impaired social skills involving multiple domains. ASD is not uncommon. High SRS-2 scores in patients with AHC support referral to ASD evaluation. Our findings are consistent with current understandings of the pathophysiology of AHC and ASD, both thought to involve GABAergic dysfunction. WHAT THIS PAPER ADDS: Most patients with alternating hemiplegia of childhood (AHC) have impaired social skills involving multiple domains. These impairments are significant compared to population means. Most patients with AHC have high Social Responsiveness Scale, Second Edition (SRS-2) scores. Patients with AHC with high SRS-2 scores are likely to have autism spectrum disorder.