Iodine-123 metaiodobenzylguanidine scintigraphy and iodine-123 ioflupane single photon emission computed tomography in Lewy body diseases: complementary or alternative techniques?

PURPOSE

To compare myocardial sympathetic imaging using (123)I-Metaiodobenzylguanidine (MIBG) scintigraphy and striatal dopaminergic imaging using (123)I-Ioflupane (FP-CIT) single photon emission computed tomography (SPECT) in patients with suspected Lewy body diseases (LBD).

METHODS

Ninety-nine patients who performed both methods within 2 months for differential diagnosis between Parkinson's disease (PD) and other parkinsonism (n = 68) or between dementia with Lewy bodies (DLB) and other dementia (n = 31) were enrolled. Sensitivity, specificity, accuracy, positive and negative predictive values of both methods were calculated.

RESULTS

For (123) I-MIBG scintigraphy, the overall sensitivity, specificity, accuracy, positive and negative predictive values in LBD were 83%, 79%, 82%, 86%, and 76%, respectively. For (123)I-FP-CIT SPECT, the overall sensitivity, specificity, accuracy, positive and negative predictive values in LBD were 93%, 41%, 73%, 71%, and 80%, respectively. There was a statistically significant difference between these two methods in patients without LBD, but not in patients with LBD.

CONCLUSIONS

LBD usually present both myocardial sympathetic and striatal dopaminergic impairments. (123)I-FP-CIT SPECT presents high sensitivity in the diagnosis of LBD; (123)I-MIBG scintigraphy may have a complementary role in differential diagnosis between PD and other parkinsonism. These scintigraphic methods showed similar diagnostic accuracy in differential diagnosis between DLB and other dementia.

Cardiovascular-sleep interaction in drug-naïve patients with essential grade I hypertension

Lack of nighttime blood pressure (BP) reduction by 10-20% from the mean daytime values (dipping) has been described as a distinguishing feature of essential hypertension and associated, also in normotensive subjects, with increased cardiovascular (CV) risk. Mechanisms involved in the loss of the nocturnal dip are still unclear, but involvement of autonomic nervous system (ANS) activity probably plays a crucial role. Sleep is fundamental in modulating ANS activity to maintain the physiological BP circadian rhythm, and for this reason its integrity has been widely investigated in hypertension. We investigated, under controlled conditions, the autonomic control of the CV system through an autonomic reflex screen in the awake condition and by assessment of circadian rhythm-, day-night-, time-, and state-dependent changes of BP and heart rate (HR) and associated sleep parameters in patients with a recent (≤1 yr) diagnosis of essential grade I hypertension naïve of therapy. Fourteen hypertensive patients (6 males, age: 43 ± 11 yrs; body mass index [BMI]: 24 ± 3 kg/m(2)) were compared with 28 healthy controls matched for sex, age, BMI (2 controls/patient) for cardiovascular reflex and to 8 different subjects from previous controls (6 males), comparable for age and BMI, for the day-night and nighttime CV profiles during two consecutive nights. The cardiovascular reflex screen data showed increased sympathetic effect in hypertensive patients, represented by higher overshoot of BP after Valsalva maneuver. Nighttime sleep architecture during the dark period in terms of duration, representation of sleep stages, sleep fragmentation, and incidence of arousals-periodic limb movements in sleep (PLMS) and PLMS arousals-was similar in patients and controls. Hypertensive patients displayed higher 24-h BP and HR values, but their sleep-related BP decrease was significantly reduced compared with controls. The circadian rhythms of BP and HR were intact and similar in patients and controls, coupling with the expected physiological peak time. BP and HR showed normal state-dependent modulation in hypertensive patients that, however, was higher in all sleep stages compared with controls. The lowering of systolic blood pressure (SBP) during non-rapid eye movement (NREM) sleep stages 1 and 2 and REM sleep, relative to daytime wake values, was significantly attenuated in the hypertensive group, whereas it was comparable to controls during slow-wave sleep. In hypertensive patients, analysis of sleep and CV parameters in the 90 min following sleep onset and preceding morning awakening showed normal depressor effect during the first part of the night after sleep onset and significantly higher BP rise in the hours preceding morning awakening. These findings were associated with comparable sleep architecture, sleep fragmentation, incidence of arousals, and PLMS and PLMS arousals in patients and controls. Our data suggest that drug-naïve essential grade I hypertension is associated with signs of increased vascular sympathetic response to standardized stress of the Valsalva maneuver during the awake condition, and during sleep with a non-dipping BP profile plus higher BP surge preceding morning awakening, assessable only by around-the-clock ambulatory BP monitoring, both representing additional CV risk already in early-stage hypertension and, therefore, requiring proper selection of pharmacological treatment.

Cost of healthcare for patients with migraine in five European countries: results from the International Burden of Migraine Study (IBMS)

Migraine is a disabling neurological disease that affects 14.7 % of Europeans. Studies evaluating the economic impact of migraine are complex to conduct adequately and with time become outdated as healthcare systems evolve. This study sought to quantify and compare direct medical costs of chronic migraine (CM) and episodic migraine (EM) in five European countries. Cross-sectional data collected via a web-based survey were screened for migraine and classified as CM (≥15 headache days/month) or EM (<15 headache days/month), and included sociodemographics, resource use data and medication use. Unit cost data, gathered using publicly available sources, were analyzed for each type of service, stratified by migraine status. Univariate and multivariate log-normal regression models were used to examine the relationship between various factors and their impact on total healthcare costs. This economic analysis included data from respondents with migraine in the UK, France, Germany, Italy, and Spain. CM participants had higher level of disability and more prevalent psychiatric disorders compared to EM. CM participants had more provider visits, emergency department/hospital visits, and diagnostic tests; the medical costs were three times higher for CM than EM. Per patient annual costs were highest in the UK and Spain and lower in France and Germany. CM was associated with higher medical resource use and total costs compared to EM in all study countries, suggesting that treatments that reduce headache frequency could decrease the clinical and economic burden of migraine in Europe. Comparing patterns of care and outcomes among countries may facilitate the development of more cost-effective care, and bring greater recognition to patients affected by migraine.

Comorbidity in perimenstrual migraine

Comorbidity may be defined as the association of two or more diseases in individuals at a frequency greater than that expected statistically by chance. Studying the co-occurrence of two disorders requires a careful statistical analysis before any clear conclusion on causality is reached. Many studies have looked for an association between migraine and many diseases, reporting several sometimes controversial comorbidities in migraine subjects. Although migraine is more common in women than in men, very few studies have analyzed the comorbidity of perimenstrual migraine, a migraine sub-type characterized by attacks of migraine without aura related to menstruation. We review the studies on migraine comorbidities, particularly migraine without aura in women.

Thalamic contribution to Sleep Slow Oscillation features in humans: a single case cross sectional EEG study in Fatal Familial Insomnia

OBJECTIVE

Studying the thalamic role in the cortical expression of the Sleep Slow Oscillation (SSO) in humans by comparing SSO features in a case of Fatal Familial Insomnia (FFI) and a group of controls.

METHODS

We characterize SSOs in a 51-year-old male with FFI carrying the D178N mutation and the methionine/methionine homozygosity at the polymorphic 129 codon of the PRNP gene and in eight gender and age-matched healthy controls. Polysomnographic (21 EEG electrodes, two consecutive nights) and volumetric- (Diffusion tensor imaging Magnetic Resonance Imaging DTI MRI) evaluations were carried out for the patient in the middle course of the disease (five months after the onset of insomnia; disease duration: 10 months). We measured a set of features describing each SSO event: the wave shape, the event-origin location, the number and the location of all waves belonging to the event, and the grouping of spindle activity as a function of the SSO phase.

RESULTS

We found that the FFI individual showed a marked reduction of SSO event rate and wave morphological alterations as well as a significant reduction in grouping spindle activity, especially in frontal areas. These alterations paralleled DTI changes in the thalamus and the cingulate cortex.

CONCLUSIONS

This work gives a quantitative picture of spontaneous SSO activity during the NREM sleep of a FFI individual. The results suggest that a thalamic neurodegeneration specifically alters the cortical expression of the SSO. This characterization also provides indications about cortico-thalamic interplays in SSO activity in humans.

REM behaviour disorder and neurodegenerative diseases

Rapid-eye movement (REM) sleep behaviour disorder (RBD) is an REM sleep parasomnia characterized by enactment of dream content during REM sleep associated with loss of muscle atonia. RBD can be either idiopathic or secondary to drugs or other diseases. The best recognized association is with neurodegenerative diseases, namely alpha-synucleinopathies. RBD may represent the first feature of neurodegeneration and can be considered an early marker of these disorders. This review describes the main clinical, pathogenetic, and therapeutic features of RBD, pointing to its association with neurodegenerative diseases and emphasizing the clinical and prognostic implications.

Oneiric stupor: the peculiar behaviour of agrypnia excitata

Agrypnia excitata (AE) is a syndrome characterized by the inability to sleep associated with a generalized motor and autonomic over-activation. AE is caused by a thalamo-limbic system dysfunction and comprises three different conditions: Fatal Familial Insomnia (FFI), Delirium Tremens (DT), and Morvan Syndrome (MS). Oneiric Stupor episodes (OS) are the peculiar motor behaviour of AE. During OS patients perform simple automatic gestures mimicking daily-life activities. This paper is the first description of the different characteristics of OS in two patients with MS and another with FFI, emphasizing the specific clinical features that reliably differentiate OS from REM sleep behaviour disorders.

Abnormal sleep-cardiovascular system interaction in narcolepsy with cataplexy: effects of hypocretin deficiency in humans

STUDY OBJECTIVE

Narcolepsy with cataplexy (NC) is associated with loss of hypocretin neurons in the lateral hypothalamus involved in the circadian timing of sleep and wakefulness, and many biologic functions including autonomic control. The authors investigated whether chronic lack of hypocretin signaling alters cardiovascular control during sleep in humans.

DESIGN

Comparison of 24-hr circadian rhythms, day-night, time- and state-dependent changes of blood pressure (BP) and heart rate (HR) in drug-free patients with NC and control subjects.

SETTING

University hospital.

PATIENTS OR PARTICIPANTS

Ten drug-free patients with NC (9 men, 1 woman) and 12 control subjects (9 men, 3 women).

INTERVENTIONS

N/A.

MEASUREMENTS AND RESULTS

Daytime BP was comparable in patients with NC and controls, but patients with NC displayed a nighttime nondipping BP pattern. The 24-hr circadian rhythmicity of BP and HR was normal in both groups. Systolic BP during nighttime rapid eye movement sleep was significantly increased in the NC group. The 24-hr HR was significantly higher in the NC group but the day-night and state-dependent HR modulations were intact. The nighttime BP pattern coupled in the NC group with increased sleep fragmentation and a higher prevalence of arousals, periodic limb movements in sleep (PLMS), and PLMS arousals. In an analysis of the sleep/cardiovascular interaction in the periods after sleep onset and preceding morning awakening, only PLMS were consistently associated with the blunted nighttime decrease in BP in the NC group.

CONCLUSIONS

Hypocretin deficiency in humans may couple with an altered nighttime BP regulation that can be associated with an increased cardiovascular risk. This finding may be the result not only of the hypocretinergic deficiency per se but also of the altered sleep/wake regulation characterizing NC.

Baroreflex modulation during sleep and in obstructive sleep apnea syndrome

This review focuses on the complex integration between cardiovascular reflexes and central autonomic influences controlling physiological sleep-dependent changes in arterial blood pressure and heart rate. A brief introduction on the anatomic and functional organization of the arterial baroreflex and the methods available to assess its function in humans is followed by an analysis of the functional interaction between autonomic nervous system and sleep mechanisms at the highest levels of brain organization. An insight into these interactions is important to shed light on the physiopathology of the most frequent complications of obstructive sleep apnea syndrome, such as sustained arterial hypertension, and excessive daytime sleepiness.

Loss of temporal retinal nerve fibers in Parkinson disease: a mitochondrial pattern?

BACKGROUND AND PURPOSE

Optic nerve involvement is frequent in mitochondrial disease, and retinal abnormalities are described in Parkinson's disease (PD).

METHODS

We evaluated retinal nerve fiber layer (RNFL) thickness by optical coherence tomography in 43 patients with PD and in 86 age-matched controls. We considered separately the eyes ipsilateral and contralateral to the most affected body side in patients with PD. ancova analysis, Pearson test, and multiple regression analysis were used (P < 0.05).

RESULTS

Patients with PD showed significantly thinner temporal RNFL thickness compared to controls (P = 0.004), more evident in the eye contralateral to the most affected body side. Average RNFL thickness significantly correlated with age in both controls and patients with PD (P-values ranging from 0.001 to 0.019), whereas in patients with PD RNFL thickness did not correlate with clinical variables.

CONCLUSIONS

Our study reveals a loss of retinal nerve fibers in the temporal quadrant in PD, which is typically susceptible in mitochondrial optic neuropathies.

Direct stimulation of the autonomic nervous system modulates activity of the brain at rest and when engaged in a cognitive task

The effect of autonomic perturbation (AP) on the central nervous system functioning is still largely unknown. Using an automated neck suction device to stimulate the carotid mechanoreceptors in the carotid sinus (parasympathetic pathway), operated synchronously with functional magnetic resonance imaging (fMRI) acquisition, we investigated the effects of AP on the activity of the brain at rest and when engaged in a visuo-spatial attention task. ECG was always recorded to index changes in autonomic function. At rest, AP induced increased activation in the insula and in the amygdala, which have been previously associated with the autonomic control and emotion processing, as well as in the caudate nucleus and in the medial temporal cortex, both implicated in cognitive functions. Despite a preserved performance during visuo-spatial attention task, AP induced increased reaction times and a positive modulation on the activation of the right posterior parietal cortex, the occipital cortex, the periaquiductal gray, and nuclei of the brainstem. We speculate that this modulation of brain activity represents, at different anatomical levels, a compensation mechanism to maintain cognitive efficiency under parasympathetic stimulation, which is traditionally considered as the system for energy regain and storage. In conclusion, this study provides the first evidence of a dynamic interaction between AP and higher level functions in humans.

Neuronal correlates to consciousness. The "Hall of Mirrors" metaphor describing consciousness as an epiphenomenon of multiple dynamic mosaics of cortical functional modules

Humans share the common intuition of a self that has access to an inner 'theater of mind' (Baars, 2003). The problem is how this internal theater is formed. Moving from Cook's view (Cook, 2008), we propose that the 'sentience' present in single excitable cells is integrated into units of neurons and glial cells transiently assembled into "functional modules" (FMs) organized as systems of encased networks (from cell networks to molecular networks). In line with Hebb's proposal of 'cell assemblies', FMs can be linked to form higher-order mosaics by means of reverberating circuits. Brain-level subjective awareness results from the binding phenomenon that coordinates several FM mosaics. Thus, consciousness may be thought as the global result of integrative processes taking place at different levels of miniaturization in plastic mosaics. On the basis of these neurobiological data and speculations and of the evidence of 'mirror neurons' the 'Hall of Mirrors' is proposed as a significant metaphor of consciousness. This article is part of a Special Issue entitled: Brain Integration.

Morvan chorea and agrypnia excitata: when video-polysomnographic recording guides the diagnosis

INTRODUCTION

Morvan chorea is an antibody-mediated limbic encephalopathy characterized by severe insomnia, mental confusion, hallucinations, enacted dreams, hyperhidrosis, and neuromyotonia.

CASE DESCRIPTION

In a 78 years old man presenting with progressive insomnia apathy and depression, a video-polysomnogram documented enacted dreams mimicking daily life activity (oneiric stupor). This finding led us to perform a search for serum antibodies to voltage-gated K+ channels, which was positive. A diagnosis of Morvan chorea was done. The patient underwent plasma exchange with complete resolution of the clinical picture.

CONCLUSIONS

Oneiric stupor may represent a useful precocious diagnostic marker in Morvan chorea.

Complex movement disorders at disease onset in childhood narcolepsy with cataplexy

Narcolepsy with cataplexy is characterized by daytime sleepiness, cataplexy (sudden loss of bilateral muscle tone triggered by emotions), sleep paralysis, hypnagogic hallucinations and disturbed nocturnal sleep. Narcolepsy with cataplexy is most often associated with human leucocyte antigen-DQB1*0602 and is caused by the loss of hypocretin-producing neurons in the hypothalamus of likely autoimmune aetiology. Noting that children with narcolepsy often display complex abnormal motor behaviours close to disease onset that do not meet the classical definition of cataplexy, we systematically analysed motor features in 39 children with narcolepsy with cataplexy in comparison with 25 age- and sex-matched healthy controls. We found that patients with narcolepsy with cataplexy displayed a complex array of ‘negative’ (hypotonia) and ‘active’ (ranging from perioral movements to dyskinetic–dystonic movements or stereotypies) motor disturbances. ‘Active’ and ‘negative’ motor scores correlated positively with the presence of hypotonic features at neurological examination and negatively with disease duration, whereas ‘negative’ motor scores also correlated negatively with age at disease onset. These observations suggest that paediatric narcolepsy with cataplexy often co-occurs with a complex movement disorder at disease onset, a phenomenon that may vanish later in the course of the disease. Further studies are warranted to assess clinical course and whether the associated movement disorder is also caused by hypocretin deficiency or by additional neurochemical abnormalities.

Italian Law "measures to guarantee the access to palliative and pain treatments": rebound on headaches' management

The Italian Law 38/2010 assures the citizens' right to have access to palliative care and to antalgic centres in case of either oncologic or non-oncologic pain. It represents an opportunity for headaches' managements in Italy, promoting the creation of regional and national networks of headache centres and local diagnostic and therapeutic clinical pathways for patient affected with headache. This law should also support collaborations between both antalgic and headache centres networks in order to promote innovative or experimental procedures for chronic and refractory headaches. Moreover, art. 10 of the Law 38/2010 may facilitate the prescription of many headache prophylactic drugs but it may be a risk for opioids overuse headache. Educational programs and the Continuous Professional Development for physicians and all different healthcare professionals in headache area are warranted.

Frovatriptan versus other triptans in the acute treatment of migraine: pooled analysis of three double-blind, randomized, cross-over, multicenter, Italian studies

The objective of the study is to systematically review the efficacy and safety of frovatriptan (F) versus rizatriptan (R), zolmitriptan (Z) and almotriptan (A), through a pooled analysis of three individual studies. 414 subjects with a history of migraine with or without aura (IHS criteria) were randomized to F 2.5 mg or R 10 mg (study 1), F 2.5 mg or Z 2.5 mg (study 2), and F 2.5 mg or A 12.5 mg (study 3). The studies had an identical multicenter, randomized, double blind, cross-over design, with each of the two treatment periods lasting not more than 3 months. The number of pain free (PF) and pain relief (PR) episodes at 2 h, and the number of sustained pain free (SPF) and recurrent episodes within the 48 h were the efficacy endpoints. 346 patients were included in the intention-to-treat analysis. Rate of PF episodes at 2 h was 30% with F and 34% with comparators (p = NS). PR episodes at 2 h were 55% for F and 59% for comparators (p = NS). SPF episodes at 48 h were also similar between the two groups (22% F vs. 21% comparators). Rate of recurrence was significantly (p < 0.001) lower under F (27 vs. 40% comparators). Drug-related adverse events were significantly (p < 0.05) less under F, particularly cardiovascular symptoms. Our systematic analysis of individual studies suggests that F has a similar immediate efficacy, but a more sustained effect and a better tolerability than R, Z and A.