Subclinical epileptiform activity in the Alzheimer continuum: association with disease, cognition and detection method.

BACKGROUND: Epileptic seizures are an established comorbidity of Alzheimer's disease (AD). Subclinical epileptiform activity (SEA) as detected by 24-h electroencephalography (EEG) or magneto-encephalography (MEG) has been reported in temporal regions of clinically diagnosed AD patients. Although epileptic activity in AD probably arises in the mesial temporal lobe, electrical activity within this region might not propagate to EEG scalp electrodes and could remain undetected by standard EEG. However, SEA might lead to faster cognitive decline in AD. AIMS: 1. To estimate the prevalence of SEA and interictal epileptic discharges (IEDs) in a well-defined cohort of participants belonging to the AD continuum, including preclinical AD subjects, as compared with cognitively healthy controls. 2. To evaluate whether long-term-EEG (LTM-EEG), high-density-EEG (hd-EEG) or MEG is superior to detect SEA in AD. 3. To characterise AD patients with SEA based on clinical, neuropsychological and neuroimaging parameters. METHODS: Subjects (n = 49) belonging to the AD continuum were diagnosed according to the 2011 NIA-AA research criteria, with a high likelihood of underlying AD pathophysiology. Healthy volunteers (n = 24) scored normal on neuropsychological testing and were amyloid negative. None of the participants experienced a seizure before. Subjects underwent LTM-EEG and/or 50-min MEG and/or 50-min hd-EEG to detect IEDs. RESULTS: We found an increased prevalence of SEA in AD subjects (31%) as compared to controls (8%) (p = 0.041; Fisher's exact test), with increasing prevalence over the disease course (50% in dementia, 27% in MCI and 25% in preclinical AD). Although MEG (25%) did not withhold a higher prevalence of SEA in AD as compared to LTM-EEG (19%) and hd-EEG (19%), MEG was significantly superior to detect spikes per 50 min (p = 0.002; Kruskall-Wallis test). AD patients with SEA scored worse on the RBANS visuospatial and attention subset (p = 0.009 and p = 0.05, respectively; Mann-Whitney U test) and had higher left frontal, (left) temporal and (left and right) entorhinal cortex volumes than those without. CONCLUSION: We confirmed that SEA is increased in the AD continuum as compared to controls, with increasing prevalence with AD disease stage. In AD patients, SEA is associated with more severe visuospatial and attention deficits and with increased left frontal, (left) temporal and entorhinal cortex volumes. TRIAL REGISTRATION: Clinicaltrials.gov, NCT04131491. 12/02/2020.

Role of cerebral hypoperfusion in multiple sclerosis (ROCHIMS): study protocol for a proof-of-concept randomized controlled trial with bosentan.

BACKGROUND: Axonal degeneration is related to long-term disability in patients with multiple sclerosis (MS). The underlying mechanism remains ill understood but appears to involve axonal energetic dysfunction. A globally impaired cerebral blood flow (CBF) has been observed in the normal-appearing white matter (NAWM) of patients with MS, which is probably related to astrocytic overexpression of endothelin-1 (ET-1). Cerebral hypoperfusion has been associated with reduced mitochondrial activity and disabling symptoms (e.g. fatigue and cognitive decline) of MS. Countering this process could therefore be beneficial in the disease course. Short-term CBF restoration with a single 62.5-mg dose of the ET-1 receptor antagonist bosentan has already been demonstrated in patients with MS. METHODS: The ROCHIMS study is a proof-of-concept double-blind randomized clinical trial in which patients with relapsing-remitting MS will receive either 62.5 mg bosentan or matching placebo twice daily during 28 ± 2 days. Clinical evaluation and brain magnetic resonance imaging (MRI) will be performed at baseline and treatment termination. Based on previous work, we expect a global increase of CBF in the individuals treated with bosentan. The primary outcome measure is the change of N-acetyl aspartate in centrum semiovale NAWM, which is a marker of regional axonal mitochondrial activity. Other parameters of interest include changes in fatigue, cognition, motor function, depression, and brain volume. DISCUSSION: We hypothesize that restoring cerebral hypoperfusion in MS patients improves axonal metabolism. Early positive effects on fatigue and cognitive dysfunction related to MS might additionally be detected. There is a medical need for drugs that can slow down the progressive axonal degeneration in MS, making this an important topic of interest. TRIAL REGISTRATION: Clinical Trials Register, EudraCT 2017-001253-13 . Registered on 15 February 2018.

Bilateral low frequency rTMS of the primary motor cortex may not be a suitable treatment for levodopa-induced dyskinesias in late stage Parkinson's disease.

BACKGROUND: In late stage Parkinson patients there is an unmet need for new treatments to adequately control motor complications, especially dyskinesias. In several preliminary studies, it has been suggested that applying unilateral low-frequency repetitive transcranial magnetic stimulation (LF rTMS), delivered at the primary motor cortex (MC) or the supplementary motor area (SMA), may reduce levodopa-induced dyskinesias (LID), either in a single or a multiple session stimulation protocol. In our current clinical research, we examined whether single or multiple (accelerated) sham-controlled bilateral LF rTMS session(s) applied to the primary motor cortices are able to reduce levodopa-induced dyskinesias in patients with advanced Parkinson's disease. METHODS: During a levodopa challenge test, we first investigated the effect of a single sham-controlled session of LF rTMS (1 Hz) to both left and right primary motor cortical areas on dyskinesias and motor function in nine late-stage Parkinson patients. In a second study, patients were assigned to a five day sham-controlled bilateral motor cortex cross-over accelerated LF rTMS protocol and effects on dyskinesias, motor and executive function and emotional status were assessed. RESULTS: We found no significant clinical change in levodopa-induced dyskinesias and motor function with either stimulation protocol. CONCLUSIONS: One or multiple bilateral LF rTMS session(s) applied to the primary motor cortex were unable to reduce levodopa-induced dyskinesias in late-stage Parkinson patients.

Fluoxetine in progressive multiple sclerosis (FLUOX-PMS): study protocol for a randomized controlled trial.

BACKGROUND: Currently available disease-modifying treatments acting by modifying the immune response are ineffective in progressive multiple sclerosis (MS), which is caused by a widespread axonal degeneration. Mechanisms suspected to be involved in this widespread axonal degeneration are reduced axonal energy metabolism, axonal glutamate toxicity, and reduced cerebral blood flow. Fluoxetine might theoretically reduce axonal degeneration in MS because it stimulates energy metabolism through enhancing glycogenolysis, stimulates the production of brain-derived neurotrophic factor, and dilates cerebral arterioles. The current document presents the protocol of a clinical trial to test the hypothesis that fluoxetine slows down the progressive phase of MS. METHODS/DESIGN: The FLUOX-PMS trial is a multi-center, randomized, controlled and double-blind clinical study. A total of 120 patients with the diagnosis of either secondary or primary progressive MS will be treated either by fluoxetine (40 mg daily) or placebo for a total period of 108 weeks. The primary endpoint is the time to confirmed disease progression defined as either at least a 20% increase in the timed 25-Foot Walk or at least a 20% increase in the 9-Hole Peg Test. Secondary endpoints include the Hauser ambulation index, cognitive changes, fatigue, magnetic resonance imaging of the brain, and in a small subgroup optical coherence tomography. DISCUSSION: The FLUOX-PMS trial will gives us information as to whether fluoxetine has neuroprotective effects in patients with progressive MS. TRIAL REGISTRATION: Eudra-CT: 2011-003775-11.