LRRK2 G2019S impact on Parkinson disease; clinical phenotype and treatment in Tunisian patients.

Background: LRRK2-G2019S is the most frequent mutation in North African Parkinson's disease (PD) patients.Data on its impact on disease progression and treatment response remains elusive.Therefore, we aimed to explore the clinical features,treatments,and complications through the disease course of PD Tunisian patients according to their LRRK2-G2019S profile. Methods: Longitudinal retrospective study conducted in the department of Neurology,Razi University Hospital.We included clinically diagnosed PD patients according to the MDS criteria and reviewed their medical records for clinical,treatment, and neuropsychological assessments.LRRK2-G2019S mutation was screened among all cases using Sanger sequencing.The correlation of LRRK2-G2019S and the clinical PD features was then evaluated. Results: We included 393 PD patients with 41.5% of cases were mutated for LRRK2-G2019S. Those with mutation exhibited an earlier age of onset(p=0.017),and female-PD cases had a higher mutation frequency (p=0.008).Mutation carriers displayed distinct clinical features,with a higher frequency of postural instability gait difficulty (PIGD)forms(adjusted-p<0.001).Throughout the disease progression,carriers showed a faster annual progression in UPDRS-III scores (adjusted-p=0.009) and a significantly higher Levodopa Equivalent Dosevalues in later stages(1060.81 vs. 877.83 for 6-8 years).Motor complications such as dyskinesia (adjusted-p<0.001) and motor fluctuations(31.9% vs. 25.7%,adjusted-p<0.001) were more prevalent in carriers,particularly in later stages.LRRK2-G2019S carriers also exhibited a lower prevalence of non-motor symptoms including cognitive disordersfor episodic memory(adjusted-p<0.001),attention(adjusted-p<0.001),and dysexecutive disorders (adjusted-p=0.039),as well asneuropsychiatric symptoms and dysautonomic signs. Conclusion: This study demonstrated the variability of clinical profile among Tunisian PD cases explained by the incomplete penetrance of LRRK2-G2019S that increases with age.Further studies with biomarker and disease progression data are necessary to improve PD management.

Subtypes of Dementia with Lewy Bodies: Clinical Features, Survival, and Apolipoprotein E Effect.

Background: Dementia with Lewy bodies (DLB) is a progressive neurodegenerative disease with various clinical symptoms. Limited data have described the clinical subtypes of DLB. Objective: We aimed to compare clinical subtypes of DLB according to initial symptoms and to study the effect of Apolipoprotein E (APOE) gene in DLB. Methods: We included DLB patients classified into three groups based on initial symptoms: non-motor onset (cognitive and/or psychiatric) (NMO-DLB), motor onset (parkinsonism and/or gait disorders) (MO-DLB), and mixed onset (non-motor and motor symptoms) (MXO-DLB). Clinical and APOE genotype associations and survival were analyzed. Results: A total of 268 patients were included (NMO-DLB = 75%, MXO-DLB = 15.3%, MO-DLB = 9.7%). Visual hallucinations were more frequent (p = 0.025), and attention was less commonly impaired in MXO-DLB (p = 0.047). When adjusting with APOE ɛ4 status (APOE genotype performed in 155 patients), earlier falls and frontal lobe syndrome were more common in MXO-DLB (p = 0.044 and p = 0.023, respectively). The median MMSE decline was 2.1 points/year and the median FAB decline was 1.9 points/year, with no effect of clinical subtypes. Median survival was 6 years. It was similar in DLB subtypes (p = 0.62), but shorter for patients with memory symptoms at onset (p = 0.04) and for males (p = 0.0058). Conclusions: Our study revealed a few differences between DLB clinical subtypes. APOE ɛ4 appears to be associated with earlier falls and a higher prevalence of frontal syndrome in MXO-DLB. However, DLB clinical subtypes did not impact on survival. Nevertheless, survival analysis identified other poor prognosis factors, notably inaugural memory impairment and male gender.

Psychiatric Symptoms in Stiff-Person Syndrome: A Systematic Review and a Report of Two Cases.

BACKGROUND: The clinical spectrum of stiff-person syndrome (SPS) encompasses a wide range of signs including psychiatric symptoms (PS). OBJECTIVE: Our objective was to provide an overview of the spectrum of PS in SPS through a systematic literature search and 2 illustrative case reports. METHODS: We reported 2 anti-glutamic acid decarboxylase-positive SPS cases that presented with phobic disorder, and we performed a systematic review by following the 2020 Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Articles published in PubMed, MEDLINE on Ovid, Embase, and via a manual search before October 20, 2020, were selected by 2 independent reviewers. Original studies, case reports, editorials, commentaries, and letters to the editor reporting cases of SPS with PS were all included. Conference abstracts, reviews and book chapters, unavailable articles, and those not reporting SPS cases or PS were excluded. Quantitative summary data were calculated. RESULTS: In addition to our 2 cases, we identified 237 cases of SPS with PS from 74 additional included publications totaling 239 patients. Anxiety (56%) and depression (45%) were the most common PS in SPS. Mean diagnostic delay was 4.7 years. Among the 3 SPS phenotypes, the classic form was predominant (77%), followed by stiff-limb syndrome (13%) and progressive encephalomyelitis with rigidity and myoclonus (10%). The most frequent etiology of SPS with PS was autoimmune (90%), followed by cryptogenic (7%) and paraneoplastic forms (7%). These patients were mainly treated with immune-mediated therapies and GABAergic drugs. CONCLUSIONS: Our review revealed that the most common PS of SPS are anxiety and depression occurring mostly in autoimmune and classic forms, allowing a clearer understanding of this entity, which may lead to earlier diagnosis and better outcome.

Determinants of cognitive impairment in multiple system atrophy: Clinical and genetic study.

INTRODUCTION: Classically, cognitive impairment (CI) was not considered as a paramount feature of multiple system atrophy(MSA) in both parkinsonian(MSA-P) and cerebellar(MSA-C) motor-subtypes. Yet, growing evidence indicates currently the commonness of such deficits among MSA patients in different populations. Our aim was to evaluate the cognitive profile of MSA Tunisian patients and to analyze the underlying clinical and genetic determinants. METHODS: In a retrospective cross-sectional study, clinically-diagnosed MSA patients were included. All subjects underwent clinical and neuropsychological assessments to characterize their cognitive profile. The associations with their APOE genotype status were analyzed. Determinant of CI were specified. RESULTS: We included 71 MSA patients. Female gender(sex-ratio = 0.65) and MSA-P subtype(73%) were predominant. Mean age of disease onset was 59.1years. CI was found in 85.7% of patients(dementia in 12.7% and Mild cognitive impairment(MCI) in 73% of patients mainly of multiple-domain amnestic type(37.3%)). Mean MMSE score was lower among MSA-P compared to MSA-C(23.52 vs. 26.47;p = 0.027). Higher postural instability gait disorder(PIGD) and MDS-UPDRS-III scores were noted in demented MSA patients(p = 0.019;p = 0.015 respectively). The main altered cognitive domain was attention(64.8%). Executive functions and mood disorders were more affected in MSA-P(p = 0.029,p = 0.035 respectively). Clinical and neurophysiological study of dysautonomia revealed no differences across cognitive subtypes. APOE genotyping was performed in 51 MSA patients with available blood samples. Those carrying APOEε4 had 1.32 fold higher risk to develop CI, with lower MMSE score(p = 0.0001). Attention and language were significantly altered by adjusting the p value to APOEɛ4 carriers(p = 0.046 and p = 0.044 respectively). Executive dysfunction was more pronounced among MSA-PAPOEε4 carriers(p = 0.010). CONCLUSION: In this study, the main determinants of CI in Tunisian MSA patients were MSA-P motor-subtype, mainly of PIGD-phenotype, disease duration and APOEε4 carrying status, defining a more altered cognitive phenotype. This effect mainly concerned executive, attention and language functions, all found to be more impaired in APOEε4 carriers with variable degrees across MSA motor-subtypes.

Non-motor features of essential tremor with midline distribution.

BACKGROUND: Midline essential tremor (Mid-ET) is a distinctive group of essential tremor (ET) in which tremor affects the neck, jaw, tongue, and/or voice. For long, it has been considered as an ultimate stage of the disease and a marker of its severity. However, recent studies pointed its complexity in terms of non-motor presentation. Thus, we aimed to investigate the non-motor signs (NMS) in Mid-ET. DESIGN: We conducted a cross-sectional study in a tertiary neurology referral center including ET patients classified into two groups based on the presence or not of midline tremor (Mid-ET vs. No-Mid-ET). We assessed NMS using the non-motor severity scale (NMSS), a large battery of cognitive tests, clinical and electrophysiological study of the autonomic nervous system along with the evaluation of sleep disturbances. RESULTS: A total of 163 patients were included: Mid-ET (n = 79) and No-Mid-ET (n = 84) matched in gender and age of onset. Mid-ET patients had higher proportion of late-onset ET (> 60 years old, p = 0.002) and more extrapyramidal signs (p = 0.005). For NMS, Mid-ET was marked with cognitive dysfunction (p = 0.008). The hallmarks of the neuropsychiatric profile of Mid-ET were executive dysfunction (p = 0.004), attention problems (p < 0.000), episodic memory impairment (p = 0.003), and greater depression (p = 0.010). The presence of RBD was a trait of Mid-ET (p = 0.039). In both Mid-ET and No-Mid-ET phenotypes, clinical and neurophysiological dysautonomia correlated with cognitive dysfunction. CONCLUSION: Mid-ET patients had greater cognitive dysfunction, depression, RBD, higher proportion of late-onset ET, and more extrapyramidal signs. Taken all together, these findings could provide a redesigned insight into the underlying physiopathology of Mid-ET indicative of a greater cerebellar dysfunction.

Stroke in Djibouti.

Background: Stroke is a neurological emergency affecting both developed and developing countries. In Djibouti, stroke is the fourth leading cause of death. Our objective was to describe the demographic, clinical, paraclinical profile of stroke in Djibouti and identify the possible underlying risk factors. Methods: We conducted a cross-sectional multicentre study carried out over a period of 6 months in the medical services of the Soudano-Djibouti military hospital, the General Peltier hospital and the emergency department of the National fund for social security health centre. Results: A total of seventy patients were included. The mean age was 59.61 years with a male predominance (sex ratio: 2.5) and a statistically significant female-related difference beyond the age of 60 years (p <10-3). Cardiovascular risk factors were mainly hypertension (73%), khat chewing (64%) and tobacco use (50%). Khat chewing and tobacco use were associated with a younger age of occurrence of stroke (p=0.020 and p=0.004, respectively). Diabetes mellitus and hypercholesterolemia were found respectively in 30% and 19% of cases, and were more associated with ischemic stroke. Coronary disease (11%), heart failure (3%) and obesity (4%) (significantly associated with the female gender; p= 0,021) were less common. Motor deficits (94%) were the most common clinical manifestations, followed by sensory deficits (51%) and alteration of consciousness (37%). Stroke was ischemic in 61.5% of patients. The most affected territory in ischemic stroke was the territory of the middle cerebral artery, and capsulo-thalamic involvement in haemorrhagic stroke which was significantly associated with the alteration of consciousness(p=0,003). Discussion: Stroke had primarily modifiable risk factors in Djiboutian patients dominated by high blood pressure, tobacco use and khat chewing especially in the male population under the age of 60 years. These findings could have implications on future preventive measures and a better approach to public health policy.

Heart rate variability and sympathetic skin response for the assessment of autonomic dysfunction in leucine-rich repeat kinase 2 associated Parkinson's disease.

OBJECTIVES: We aimed to assess and compare autonomic function in Parkinson's disease (PD) associated with the leucine-rich repeat kinase (LRRK2) G2019S mutation (LRRK2-PD) and non-LRRK2 PD, by the study of heart rate variability (HRV) and sympathetic skin responses (SSR). METHODS: In a cross-sectional three-year study, fifty LRRK2-PD and fifty clinically matched non-LRRK2 PD patients were included. Cardiac parasympathetic functions were assessed using heart rate variation to deep breathing (HR-DB), to the Valsalva maneuver (HR-V) and to standing (HR-S) and the sympathetic autonomic system by sympathetic skin responses (SSR). RESULTS: Neurophysiological, parasympathetic and sympathetic dysautonomia were found in 78%, 69% and 37% of all PD patients respectively. Rates of dysautonomia in the LRRK2-PD and non-LRRK2 PD patient subgroups were 76% vs 80% (p = 0.405) for neurophysiological, 62% vs 76% (p = 0.123) for parasympathetic and 38% vs 36% (p = 0.500) for sympathetic dysautonomia. HR-S was the most frequently altered parameter in both groups, and was significantly associated with the tremor-dominant (TD) motor phenotype of PD in the total cohort (p = 0.004) and in LRRK2-PD (p = 0.015). In LRRK2-PD patients, female gender was associated with parasympathetic dysfunction (p = 0.024), and with altered HR-DB (p = 0.022). Early-onset parkinsonism was also significantly associated with preserved neurophysiological autonomic functions (p = 0.044) in LRRK2-PD. In non-LRRK2 PD patients, male gender was associated with early parasympathetic (p = 0.043) and sympathetic dysfunction (p = 0.007). CONCLUSION: Our study showed a roughly similar neurophysiological autonomic profile in non-LRRK2 PD and LRRK2-PD. The latter had some peculiarities with more marked parasympathetic dysfunction and more altered HR-DB in females, more altered HR-S in the TD-motor phenotype, and preserved autonomic functions in early-onset parkinsonism. These preliminary findings would require further investigations on larger genetically homogeneous cohorts to explore the multiple facets of autonomic dysfunction in PD.