Neuroanatomical findings in isolated REM sleep behavior disorder and early Parkinson's disease: a Voxel-based morphometry study.

Isolated rapid eye movement (REM) sleep behavior disorder (iRBD) is a parasomnia characterized by loss of physiological atonia of skeletal muscles with abnormal behaviors arising during REM sleep. RBD is often the early manifestation of neurodegenerative diseases, particularly alpha-synucleinopathies, such as Parkinson's disease (PD). Both structural and functional neuroimaging studies suggest that iRBD might share, or even precede, some of the features commonly found in PD, although without a definitive conclusion. Aim of the study is to evaluate the presence of structural abnormalities involving cortical and subcortical areas in PD patients with RBD and iRBD. Patients with video-polysomnographic (VPSG)-confirmed iRBD, and patients with a diagnosis of PD were recruited. In all PD patients, the presence of probable RBD was assessed during the follow-up visits (PD/pRBD). A group of healthy controls (HC) subjects was also recruited. Each subject underwent a structural brain MRI using a 3-D T1-weighted spoiled gradient echo sequence. Twenty-three patients with iRBD, 24 PD/pRBD, and 26 HC were enrolled. Voxel-based morphometry-AnCOVA analysis revealed clusters of grey matter changes in iRBD and PD/pRBD compared to HC in several regions, involving mainly the frontal and temporal regions. The involvement of cortical brain structures associated to the control of sleep cycle and REM stage both in PD/pRBD and iRBD might suggest the presence of a common structural platform linking iRBD and PD, although this pattern may not underlie exclusively RBD-related features. Further longitudinal studies are needed to clarify the patterns of changes occurring at different time points of RBD-related neurodegeneration.

Obsessive-compulsive personality disorder in rapid eye movement sleep behavior disorder.

Rapid eye movement sleep behavior disorder (RBD) is a common prodromic non-motor symptom of Parkinson's disease (PD). Only few studies have evaluated the personality of RBD patients with conflicting results. Aim of the study was to evaluate the frequency of Personality Disorders (PeDs)in RBD. RBD patients, PD patients and healthy controls (HC) were enrolled. All the enrolled subjects underwent a full neurological examination. Motor symptoms were evaluated with the UPDRS-Motor Examination. PeDs were assessed with the Structured Clinical Interview for DSM-IV Personality Disorders (SCID-II). Twenty-nine RBD patients [14 men (48.3%); mean age 55.6 ± 11.1], 30 PD patients [17 men (56.7%); mean age 65.7 ± 10.7] and 30 HC [12 men (40%); mean age 65.7 ± 5.4] were enrolled in the study. PD patients had a disease duration of 4.5 ± 4.6 and presented a mean UPDRS-ME score of 26.7 ± 9.4. The most frequent PeDs was the Obsessive-Compulsive one (OCPeD); OCPeD was significantly more frequent in RBD (55.2%) patients than HC (13.3%; p-value < 0.001). No significant differences were found comparing the frequency of OCPeD in RBD patients to that in PD. In the present study, the prevalence of OCPeD in RBD patients was close to that reported in PD patients. Our data could suggest the existence of a common disease-specific RBD-PD personality profile.

Pure sensitive chronic inflammatory axonal polyneuropathy following Pfizer COVID-19 vaccine.

BACKGROUND: During the worldwide mass vaccination campaign against SARS-CoV-2, multiple side effects have been observed. We described the case of a patient who developed pure sensitive chronic inflammatory axonal polyneuropathy (CIAP) in a close temporal relationship with the administration of the BNT162b2 (Pfizer®) vaccine. CASE REPORT: An 82-year-old woman developed lower limb sensory loss and "pricking" associated with marked gait imbalance after she had received her second dose of Pfizer-BioNTech COVID-19 vaccine. At the electroneurographic examination, the motor nerves conduction study was normal. Median, ulnar, and sural nerves sensory compound nerve action potential (CNAP) were bilaterally absent. Somatosensory evoked potentials (SSEPs) were not recordable. Spine MRI demonstrated roots enhancement from C3 to Th2 and diffuse enhancement of cauda equina nerve roots. She was treated with IV methylprednisolone whit benefit. A follow-up visit was made 4 months after the disease onset; a diagnosis of pure sensitive CIAP has been made. DISCUSSION: To the best of our knowledge, this is the first description of CIAP occurring in a close temporal relationship with the administration of Pfizer-BioNTech COVID-19 vaccine.

Prevalence of isolated RBD in the city of Catania, Italy: a population-based study.

STUDY OBJECTIVES: Few studies have analyzed the prevalence of isolated rapid eye movement sleep behavior disorder (RBD) giving different estimates. Aim of the study was to estimate the prevalence of isolated RBD in the city of Catania. METHODS: A 3-stage design was adopted. Participants attending the offices of general practitioners in the city of Catania were screened with the RBD Single Question Screen questionnaire (Stage I). Positive participants were interviewed by phone and, if suspected of RBD, were invited for clinical examination by a movement disorders specialist and a sleep specialist (Stage II). After the clinical examination, patients diagnosed as probable isolated RBD (pRBD) were invited to undergo a video polysomnography (Stage III) to confirm the diagnosis of definite RBD. RESULTS: A total of 1,524 participants were screened. Of these, 220 (14.4%) screened positive. One hundred forty-three of them were further screened by phone, of whom 75 were suspected RBD. Thirty-six patients were diagnosed as pRBD, giving a prevalence of 2.36% (95% confidence interval, 1.71-3.25). Twelve pRBD agreed to a video polysomnography and, of these, 4 were diagnosed as definite RBD, giving a prevalence of 0.26% (95% confidence interval, 0.07-0.67). Prevalence adjusted by nonparticipants was 3.48% (95% confidence interval, 2.67-4.52) and 1.18% (95% confidence interval, 0.45-1.37) for pRBD and definite RBD, respectively. CONCLUSIONS: Prevalence of both pRBD and definite RBD in Italy is comparable to the estimates reported in literature, confirming that isolated RBD has a low prevalence in the general population. CITATION: Cicero CE, Giuliano L, Sgroi R, et al. Prevalence of isolated RBD in the city of Catania, Italy: a population-based study. J Clin Sleep Med. 2021;17(11):2241-2248.