Incidence and predictors of postural abnormalities in Parkinson's disease: a PPMI cohort study.

BACKGROUND: Axial postural abnormalities (PA) are invalidating symptoms of Parkinson's disease (PD). Risk factors for PA are unknown. OBJECTIVES: We sought to evaluate PA incidence and risk factors over the first 4-6 years of PD. METHODS: We included 441 PD patients from the Parkinson's Progression Markers Initiative (PPMI) cohort with data at diagnosis and after 4-year follow-up. PA was defined according to a posture item ≥ 2 at the Movement Disorder Society-sponsored-revision of the Unified Parkinson's Disease Rating Scale (MDS-UPDRS) in Off therapeutic condition. The Kruskal-Wallis test was used to compare characteristics of patients without PA ('no-PA'), with PA at disease onset ('baseline-PA'), and PA developed during follow-up ('develop-PA'). To identify predictors of PA development, univariate and multivariate Cox regression analyses were performed considering demographic, clinical and therapeutic variables. RESULTS: 10.9% of patients showed PA at baseline and 23.7% developed PA within the first 4-6 years since diagnosis. Older age, malignant phenotype, higher MDS-UPDRS part III, Hoehn & Yahr, and dysautonomia (SCOPA-AUT) score, and lower levels of physical activity were predictors of PA development at the univariate analysis. Older age (Hazard ratio [HR] per year: 1.041) and higher MDS-UPDRS part III score (HR per point: 1.035) survived as PA development predictors in the multivariate analysis. CONCLUSIONS: PPMI cohort data show that > 30% of PD patients present PA within the first 4-6 years of disease. Older age at onset and higher motor burden are associated with a higher risk for PA development. The protective role of physical activity merits to be further investigated.

Effects of Continuous Dopaminergic Stimulation on Parkinson's Disease Gait: A Longitudinal Prospective Study with Levodopa Intestinal Gel Infusion.

Background: Gait issues, including reduced speed, stride length and freezing of gait (FoG), are disabling in advanced phases of Parkinson's disease (PD), and their treatment is challenging. Levodopa/carbidopa intestinal gel (LCIG) can improve these symptoms in PD patients with suboptimal control of motor fluctuations, but it is unclear if continuous dopaminergic stimulation can further improve gait issues, independently from reducing Off-time. Objective: To analyze before (T0) and after 3 (T1) and 6 (T2) months of LCIG initiation: a) the objective improvement of gait and balance; b) the improvement of FoG severity; c) the improvement of motor complications and their correlation with changes in gait parameters and FoG severity. Methods: This prospective, longitudinal 6-months study analyzed quantitative gait parameters using wearable inertial sensors, FoG with the New Freezing of Gait Questionnaire (NFoG-Q), and motor complications, as per the MDS-UPDRS part IV scores. Results: Gait speed and stride length increased and duration of Timed up and Go and of sit-to-stand transition was significantly reduced comparing T0 with T2, but not between T0-T1. NFoG-Q score decreased significantly from 19.3±4.6 (T0) to 11.8±7.9 (T1) and 8.4±7.6 (T2) (T1-T0 p = 0.018; T2-T0 p <  0.001). Improvement of MDS-UPDRS-IV (T0-T2, p = 0.002, T0-T1 p = 0.024) was not correlated with improvement of gait parameters and NFoG-Q from T0 to T2. LEDD did not change significantly after LCIG initiation. Conclusion: Continuous dopaminergic stimulation provided by LCIG infusion progressively ameliorates gait and alleviates FoG in PD patients over time, independently from improvement of motor fluctuations and without increase of daily dosage of dopaminergic therapy.

Neurological symptoms in adults with Gaucher disease: a systematic review.

INTRODUCTION: Gaucher disease (GD) is classically divided into three types, based on the presence or absence of neurological signs and symptoms. However, presentation can be highly variable in adulthood, and this aspect has not been adequately addressed in the literature so far. We performed a systematic literature review to analyze the entire spectrum of neurological manifestations in adult patients previously classified as GD type I, II, or III, evaluating the role of variants in different neurological manifestations. METHODS: We searched databases for studies reporting clinical data of adult GD patients (age ≥ 18). Data extraction included GD types, GBA1 variants, age at disease onset and diagnosis, duration of GD, and age at onset and type of neurological symptoms reported. RESULTS: Among 4190 GD patients from 85 studies, 555 exhibited neurological symptoms in adulthood. The median age at evaluation was 46.8 years (IQR 26.5), age at neurological symptoms onset was 44 years (IQR 35.1), and age at GD clinical onset was 23 years (IQR 23.4). Parkinsonism, including Parkinson's disease and Lewy Body dementia, was the most reported neurological manifestation. Other symptoms and signs encompassed oculomotor abnormalities, peripheral neuropathy, seizures, myoclonus, and cerebellar, cognitive and psychiatric symptoms. The genotype N370S/N370S mostly presented with Parkinsonism and the L444P variant with severe and earlier neurological symptoms. CONCLUSION: The findings of this systematic review highlight: (1) the relevance of a comprehensive neurological assessment in GD patients, and (2) the importance of considering possible undiagnosed GD in adult patients with mild systemic symptoms presenting unexplained neurological symptoms.

CACNA1A variant associated with generalized dystonia.

INTRODUCTION: CACNA1A gene variants are correlated with different disorders, including episodic ataxia type 2, spinocerebellar ataxia type 6, and familial hemiplegic migraine type 1. Despite dystonia not being a typical manifestation of CACNA1A variants, there are reports indicating a link between this gene mutation and dystonic features. METHODS: We report the case of a patient with a novel missense variant of the CACNA1A gene presenting headache, head and arm tremor, dystonia, episodic painful focal dystonic attacks, and unexplained falls. RESULTS:  A 57-year-old woman presented with a history of neck dystonia, head and arm tremor, and headaches since age 15. In 2017, she progressively developed dystonic tremor of the head and arms with an unremarkable brain MRI. In 2018 she experienced worsening of tremor and developed painful dystonic attacks, resistant to treatments including clonazepam, trihexyphenidyl, baclofen, and levodopa/benserazide. Botulinum toxin injections for neck dystonia provided limited benefit. The next-generation sequencing exam revealed a CACNA1A gene missense variant (NM_023035.2:c.1630C > T; p.Arg544Trp). In 2021 we observed a worsening of dystonia, accompanied by weight loss, mood changes, and unexplained falls. Deep brain stimulation was considered but ruled out due to cortical atrophy and mild cognitive deficits revealed by the neuropsychological examination. DISCUSSION: Only a few studies reported dystonia as part of the clinical features in carriers of CACNA1A mutations. This case points out the relevance of a need to expand the literature on voltage-dependent P/Q-type Ca2 + channels' role in dystonia's pathogenesis and stresses the complex phenotype-genotype presentation of CACNA1A mutation.

Effects of dopaminergic therapy on sleep quality in fluctuating Parkinson's disease patients.

BACKGROUND: Sleep disorders negatively impact quality of life in Parkinson's disease (PD), yet the role of antiparkinsonian drugs on sleep quality is still unclear. We aimed to explore the correlation between sleep dysfunction and dopaminergic therapy in a large cohort of advanced PD patients. METHODS: Patients consecutively evaluated for device-aided therapies eligibility were evaluated by means of the PD Sleep Scale (PDSS-2; score ≥ 18 indicates poor sleep quality), and the Epworth Sleepiness Scale (ESS score ≥ 10 indicates excessive daytime sleepiness-EDS). Binary logistic regression analysis, adjusting for age, sex, disease duration, motor impairment, and sleep drugs, was employed to evaluate the association between dopaminergic therapy and PDSS-2 and ESS scores. Analysis of covariance assessed differences in PDSS-2 and ESS scores between patients without DA, and between patients treated with low or high doses of DA (cut-off: DA-LEDD = 180 mg). RESULTS: In a cohort of 281 patients, 66.2% reported poor sleep quality, and 34.5% reported EDS. DA treatment demonstrated twofold lower odds of reporting relevant sleep disturbances (OR 0.498; p = 0.035), while DA-LEDD, levodopa-LEDD, total LEDD, and extended-release levodopa were not associated with disturbed sleep. EDS was not influenced by dopaminergic therapy. Patients with DA intake reported significant lower PDSS-2 total score (p = 0.027) and "motor symptoms at night" domain score (p = 0.044). Patients with higher doses of DA showed lower PDSS-2 total score (p = 0.043). CONCLUSION: Our study highlights the positive influence of DA add-on treatment on sleep quality in this group of advanced fluctuating PD patients.

Are patients with GBA-Parkinson disease good candidates for deep brain stimulation? A longitudinal multicentric study on a large Italian cohort.

BACKGROUND: GBA variants increase the risk of developing Parkinson disease (PD) and influence its outcome. Deep brain stimulation (DBS) is a recognised therapeutic option for advanced PD. Data on DBS long-term outcome in GBA carriers are scarce. OBJECTIVE: To elucidate the impact of GBA variants on long-term DBS outcome in a large Italian cohort. METHODS: We retrospectively recruited a multicentric Italian DBS-PD cohort and assessed: (1) GBA prevalence; (2) pre-DBS clinical features; and (3) outcomes of motor, cognitive and other non-motor features up to 5 years post-DBS. RESULTS: We included 365 patients with PD, of whom 73 (20%) carried GBA variants. 5-year follow-up data were available for 173 PD, including 32 mutated subjects. GBA-PD had an earlier onset and were younger at DBS than non-GBA-PD. They also had shorter disease duration, higher occurrence of dyskinesias and orthostatic hypotension symptoms.At post-DBS, both groups showed marked motor improvement, a significant reduction of fluctuations, dyskinesias and impulsive-compulsive disorders (ICD) and low occurrence of most complications. Only cognitive scores worsened significantly faster in GBA-PD after 3 years. Overt dementia was diagnosed in 11% non-GBA-PD and 25% GBA-PD at 5-year follow-up. CONCLUSIONS: Evaluation of long-term impact of GBA variants in a large Italian DBS-PD cohort supported the role of DBS surgery as a valid therapeutic strategy in GBA-PD, with long-term benefit on motor performance and ICD. Despite the selective worsening of cognitive scores since 3 years post-DBS, the majority of GBA-PD had not developed dementia at 5-year follow-up.

Longitudinal Assessment of Botulinum Toxin Treatment for Lateral Trunk Flexion and Pisa Syndrome in Parkinson's Disease: Real-life, Long-Term Study.

Lateral trunk flexion (LTF) and its severe form, called Pisa syndrome (PS), are highly invalidating axial postural abnormalities associated with Parkinson's disease (PD). Management strategies for LTF lack strong scientific evidence. We present a real-life, longitudinal study evaluating long-term efficacy of botulinum toxin (BoNT) injections in axial muscles to reduce LTF and PS in PD. A total of 13 PD patients with LTF > 5° received ultrasound- and electromyography-guided BoNT injections every 4 months. Seven untreated matched PD patients with LTF served as controls and their changes in posture after 18 months were compared with those of seven patients continuing BoNT over 12 months. 53.8% of patients continued the BoNT injections for at least 12 months. Various individual LTF responses were observed. Overall, BoNT-treated patients obtained a not statistically significant improvement of LTF of 17 ± 41% (p = 0.237). In comparison, the seven untreated PD patients suffered a deterioration in LTF over 12 months by 36 ± 45% (p = 0.116), showing a significantly different trajectory of posture change (p = 0.026). In conclusion, repeated BoNT injections in axial muscles showed varying effects in managing PD-associated LTF, suggesting that: (a) a relevant number of patients with LTF can benefit from BoNT; (b) long-term treatment could prevent LTF worsening; (c) an instrumented, personalized approach is important; and (d) there is a need for prospective, long-term studies.

Axial symptoms as main predictors of short-term subthalamic stimulation outcome in Parkinson's disease.

Deep brain stimulation (DBS) is an established therapeutic option for Parkinson's disease (PD) patients; however, a clear-cut definition of subthalamic (STN) DBS predictors in PD is lacking. We analyzed a cohort of 181 STN-treated PD patients and compared pre- vs. 1-year post-surgical motor, dyskinesia, Off time, and daily-life activities (ADL) scores. A multivariate linear regression analysis was used to evaluate the association between clinical/demographic characteristics and the extent of STN-DBS response for outcomes proving a significant change after surgery. After STN-DBS, we observed a significant improvement of motor symptoms (P < 0.001), dyskinesia (P < 0.001), and daily Off time (P < 0.001). Sex, PD duration, cognitive status, and the motor and axial response to levodopa significantly explained the motor improvement (R = 0.360, P = 0.002), with presurgical response of axial symptoms (Beta = 0.203, P = 0.025) and disease duration (Beta = 0.205, P = 0.013) being the strongest predictors. Considering the daily Off time improvement, motor and axial response at the levodopa challenge test and disease duration explained 10.6% of variance (R = 0.326, p < 0.001), with disease duration being the strongest predictor of improvement (Beta = 0.253, p: 0.001) and axial levodopa response showing a trend of significance in explaining the change (Beta = 0.173, p: 0.056). Dyskinesia improvement was not significantly explained by the model. Our findings highlight the emerging role of axial symptoms in PD and their response to levodopa as potentially pivotal also in the DBS selection process.

15-Year Subthalamic Deep Brain Stimulation outcome in a Parkinson's disease patient with Parkin gene mutation: a case report.

INTRODUCTION: Parkinson's Disease (PD) patients with Parkin gene (PRKN) mutations show good response to subthalamic deep brain stimulation (STN-DBS). Currently, the longest follow-up available of these patients is 6 years. We report a very long-term outcome (more than 15 years) of a STN-DBS-treated patient with a compound heterozygous deletion of exons 3 and 11 of the PRKN gene. CASE REPORT: In 1993, a 39-year-old male was diagnosed with PD after the onset of resting tremor. Levodopa was started, and during the following 10 years, he reported good motor symptoms control, with only mild modification of levodopa intake and pramipexole introduction. In 2005, he developed disabling motor fluctuations and dyskinesia. In 2007, he underwent bilateral STN-DBS, with a marked improvement of motor symptoms and fluctuations during the following years. After 6 years, he reported mild motor fluctuations, improved after stimulation and treatment modifications. After 10 years he showed diphasic dyskinesias, feet dystonia, postural instability, and gambling (resolved after pramipexole discontinuation). In 2018, he developed a non-amnestic single-domain mild cognitive impairment (MCI). In 2023, after more than 15 years of STN-DBS, motor symptoms and fluctuations are still well controlled. He reports mild dysphagia, mild depression, and multiple-domain MCI. His quality of life is better than before surgery, and he still reports a subjective significant improvement from STN-DBS. CONCLUSION: Confirming the very long-term efficacy of STN-DBS in PRKN-mutated patients, our case report underlines their peculiar suitability for surgical treatment.

The impact of dysphagia in Parkinson's disease patients treated with levodopa/carbidopa intestinal gel.

BACKGROUND: Dysphagia is common in advanced phases of Parkinson disease (PD), and is a risk factor for aspiration pneumonia. Nonetheless, dysphagia has been poorly investigated in PD patients treated with levodopa-carbidopa intestinal gel (LCIG). We aimed to analyze the impact of dysphagia on mortality in LCIG treated patients and its relationship with other PD disability milestones. METHODS: We retrospectively evaluated 95 consecutive PD patients treated with LCIG. Kaplan-Meier and log-rank test were used to compare mortality in patients with dysphagia from others. Cox regression was used to estimate the impact of dysphagia, age, disease duration, and Hoehn and Yahr (H&Y) on mortality in the entire cohort. Finally, univariate and multivariate regression analyses were used to estimate the association between dysphagia and age, disease duration, H&Y, hallucinations, and dementia. RESULTS: A significantly higher mortality rate was observed in patients with dysphagia. In the Cox model, dysphagia was the only feature significantly associated with mortality (95%CI 2.780-20.609; p < 0.001). Univariate analyses showed a significant correlation between dysphagia and dementia (OR: 0.387; p:0.033), hallucinations (OR: 0.283; p:0.009), and H&Y score (OR: 2.680; p < 0.001); in the multivariate analysis, only the H&Y stage was associated with the presence of dysphagia (OR: 2.357; p:0.003). CONCLUSION: Dysphagia significantly increased the risk of death in our cohort of LCIG-treated patients, independently from other relevant features such as age, disease duration, dementia, and hallucinations. These findings support the management of this symptom as a priority in the advanced PD stages, even in people treated with LCIG.

How resistant are levodopa-resistant axial symptoms? Response of freezing, posture, and voice to increasing levodopa intestinal infusion rates in Parkinson disease.

BACKGROUND AND PURPOSE: Treatment of freezing of gait (FoG) and other Parkinson disease (PD) axial symptoms is challenging. Systematic assessments of axial symptoms at progressively increasing levodopa doses are lacking. We sought to analyze the resistance to high levodopa doses of FoG, posture, speech, and altered gait features presenting in daily-ON therapeutic condition. METHODS: We performed a pre-/postinterventional study including patients treated with levodopa/carbidopa intestinal gel infusion (LCIG) with disabling FoG in daily-ON condition. Patients were evaluated at their usual LCIG infusion rate (T1), and 1 h after 1.5× (T2) and 2× (T3) increase of the LCIG infusion rate by quantitative outcome measures. The number of FoG episodes (primary outcome), posture, speech, and gait features were objectively quantified during a standardized test by a blinded rater. Changes in motor symptoms, dyskinesia, and plasma levodopa concentrations were also analyzed. RESULTS: We evaluated 16 patients with a mean age of 69 ± 9.4 years and treated with LCIG for a mean of 2.2 ± 2.1 years. FoG improved in 83.3% of patients by increasing the levodopa doses. The number of FoG episodes significantly decreased (mean = 2.3 at T1, 1.7 at T2, 1.2 at T3; p = 0.013). Posture and speech features did not show significant changes, whereas stride length (p = 0.049), turn duration (p = 0.001), and turn velocity (p = 0.024) significantly improved on doubling the levodopa infusion rate. CONCLUSIONS: In a short-term evaluation, the increase of LCIG dose can improve "dopa-resistant" FoG and gait issues in most advanced PD patients with overall good control of motor symptoms in the absence of clinically significant dyskinesia.

Burden of caregiving for cardiovascular dysautonomia in Parkinson's disease.

PURPOSE: We sought to estimate the impact of cardiovascular autonomic neuropathy (cAN) on informal caregivers of patients with Parkinson's disease (PD), defined as individuals providing regular care to a friend, partner, or family member with PD, and to evaluate the mutual relationship between caregiver burden and patient health-related quality of life (HRQoL). METHODS: We enrolled 36 consecutive patients with PD and their informal caregivers. Patients underwent a detailed motor, autonomic, cognitive, and functional assessment. Caregivers were assessed using the Zarit Burden Interview (ZBI). Differences in caregiver burden, expressed by the ZBI score, and strength of association between caregiver burden, cAN, and HRQoL were assessed using analysis of covariance (ANCOVA), logistic regression, and linear regression analyses. Analyses were adjusted for patients' age, PD duration, and motor and cognitive disability, as well as caregivers' age. RESULTS: Moderate-severe caregiver burden was reported in 41.7% of PDcAN+ versus 8.7% of PDcAN- (p < 0.001). The ZBI score was increased in PDcAN+ versus PDcAN- (31.5 ± 3.4 versus 15.2 ± 2.3; p < 0.001), with tenfold higher odds (p = 0.012) of moderate-severe caregiver burden in PDcAN+, even after adjusting for potential confounders. The ZBI score correlated with cAN severity (p = 0.005), global autonomic impairment (p = 0.012), and HRQoL impairment (p < 0.001). CONCLUSION: These results highlight the significant impact of cAN on PD caregivers and the need for targeted interventions addressing this frequently overlooked and insufficiently treated source of nonmotor disability in PD.

SARS-CoV-2 vaccination, Parkinson's disease, and other movement disorders: case series and short literature review.

BACKGROUND: Several neurological complications have been reported following SARS-Cov-2 vaccination, without a clear causal relationship ever being verified, including some cases of worsening of Parkinson's disease (PD) symptoms and new onset of movement disorders in non-parkinsonian patients. METHODS: We describe two new cases of PD patients treated with device-aided therapy who developed worsening of parkinsonian symptoms after receiving the third vaccine dose (booster). We also conducted a short review of the cases reported in literature of PD symptoms worsening and new onset of movement disorders in non-parkinsonian patients after SARS-Cov-2 vaccination. RESULTS: The first patient, a 46-year-old man implanted with bilateral Subthalamic Deep Brain Stimulation, experienced temporary motor and non-motor symptoms worsening after mRNA-1273 booster, improved after stimulation settings modification. The second patient, a 55-year-old man implanted with percutaneous endoscopic transgastric jejunostomy (PEG-J) for levodopa-carbidopa intestinal gel (LCIG) infusion experienced severe temporary worsening of dyskinesia and managed through temporary LCIG dose reduction. Other seven cases of vaccine-related movement disorder are currently reported in literature, four describing PD symptoms worsening and three the onset of new movement disorders in otherwise healthy people. CONCLUSION: Both our patients and the cases described so far completely recovered after few days with parkinsonian therapy modification, symptomatic treatment, or even spontaneously, underlining the transient and benign nature of side effects from vaccine. Patients should be reassured about these complications, manageable through a prompt evaluation by the reference neurologist.

Essential tremor and cognitive impairment: who, how, and why.

BACKGROUND AND AIMS: Recent years have witnessed the switch from considering essential tremor (ET) a monosymptomatic disorder to consider it as part of a spectrum, including other neurological signs, such as mild cognitive impairment and dementia, thus defining it as "ET plus." There are few data on cognitive impairment in ET patients. The aim of this review is to analyze the clinical characteristics of ET patients developing cognitive impairment, their neuropsychological profile, the underpinning mechanisms, and the possible biomarkers. METHODS: The authors performed a narrative review on cognitive decline in essential tremor, including articles written in English since the year 2000. DISCUSSION: The most recent pathogenetic theories of cognitive impairment in ET rely on the cerebellar dysfunction, being part of the Cerebellar Cognitive Affective Syndrome spectrum. Cognitive impairment in ET patients could be assessed through many tests that demonstrate the involvement of different domains, such as attention, executive functions, and language. There are some clinical characteristics of ET that may indicate a greater risk of developing cognitive impairment, namely, cerebellar symptoms, falls, age at onset, and family history. However, there are no established clinical, neurophysiological, neuropathological, and fluid biomarkers of cognitive impairment in ET. CONCLUSIONS: Increasing data are showing in ET the presence of cerebellar symptoms and cognitive impairment. Further studies are needed to better understand cognition in ET patients, and to define the boundary between ET and ET plus, since deeper phenotyping might have important clinical and therapeutic implications.

Time to onset and duration of botulinum toxin efficacy in movement disorders.

BACKGROUND: Botulinum toxin (BoNT) is a valuable treatment in movement disorders; however, time to onset and duration of efficacy may widely differ among patients. We aimed to clarify the impact of main demographic and clinical features on time to onset and duration of BoNT efficacy. METHODS: We analyzed time-to-onset and duration of BoNT efficacy in 186 consecutive patients treated with BoNT for blepharospasm, cervical dystonia, facial hemispasm, oromandibular dystonia, limb dystonia, and sialorrhea due to Parkinsonism. The following factors were considered as potential efficacy predictors: doses and types of toxin, sex, age, years of treatment, and clinical condition. Kruskall-Wallis, Spearman correlation, and multivariate linear regression were used for statistical analysis. RESULTS: The average time to onset was 6.7 ± 5 days and duration of BONT efficacy 78.5 ± 28.4 days. Both time to onset and duration of efficacy were correlated with BoNT doses (p: 0.007 and p: 0.02). The multiple regression analysis showed that sex, age, years of BoNT treatment, doses, type of toxin, and clinical condition significantly predicted time to onset (F(11, 171) = 2.146, p: 0.020) with age being the strongest predictor (p: 0.004). The same model explained 20.1% of the variance of duration of BoNT efficacy, showing a significant prediction of the outcome (F(11, 164) = 3.754, p < 0.001), with doses (p < 0.001), type of toxin (p: 0.017), and clinical condition (p < 0.001) being the strongest predictors. CONCLUSION: Our findings suggest that age, type of toxin, clinical condition and especially doses may account for the variability of BoNT efficacy in terms of time to onset and duration.

Neurological comorbidities and COVID-19-related case fatality: A cohort study.

BACKGROUND: Neurological involvement in Coronavirus disease-2019 (COVID-19) is widely recognized. However, the role of pre-existing neurological comorbidities in modulating COVID-19-related mortality still remains unclear. This cohort study evaluates the COVID-19-related case fatality rate (CFR) of patients with pre-existing neurological diseases. METHODS: We retrospectively evaluated all patients consecutively admitted to our hospital with a diagnosis of COVID-19 between March and April 2020. We used a multivariate regression analysis to estimate the association between pre-existing neurological diseases and COVID-19-related mortality. Then, we compared the CFR and survival curves of two cohorts (patients suffering vs. those not suffering from pre-existing neurological disease), matched trough the propensity score (PS). Age and other comorbidities were considered for PS calculation. We applied a 1:1 matching for the entire neurological cohort and, separately, for cerebrovascular, neurodegenerative, and other neurological diseases. RESULTS: Among 332 patients, 75 (22.6%) were affected by pre-existing neurological disease (n = 29 cerebrovascular, n = 26 neurodegenerative, n = 20 others). From the multivariate regression analysis, they resulted with a significant increase of COVID-19-related mortality (OR:2.559; 95%CI 1.181-5.545; p < 0.017). From the cohort analysis, CFR resulted 2-fold higher in patients with neurological disease (48.0% vs. 24.0%; p = 0.002). CFR was significantly higher in patients with neurodegenerative diseases compared to matched individuals (73.9% vs. 39.1%; p = 0.017), while CFR increase in patients with cerebrovascular diseases did not reach statistical significance (48.3% vs. 41.4%; p = 0.597). CONCLUSIONS: Pre-existing neurological comorbidities, in particular neurodegenerative diseases, increase significantly COVID-19-related case fatality, indicating a clear priority for viral screening, access to care facilities and vaccination in these populations.

COVID-19 and Parkinson's Disease: What Do We Know So Far?

BACKGROUND: Many studies on Parkinson's disease (PD) patients affected by Coronavirus-disease-2019 (COVID-19) were recently published. However, the small sample size of infected patients enrolled in most studies did not allow to draw robust conclusions on the COVID-19 impact in PD. OBJECTIVE: We aimed to assess whether the prevalence and outcome of COVID-19 in PD patients are different from those observed in the general population. METHODS: We conducted a systematic review of studies reporting data on PD patients with a diagnosis of COVID-19 (PD-COVID+). We extracted prevalence, clinical-demographic data, outcome, and mortality. We also analyzed risk or protective factors based on comparisons between PD-COVID+ and control populations with PD without COVID-19 or without PD with COVID-19. RESULTS: We included 16 studies reporting on a total of 11,325 PD patients, 1,061 with a confirmed diagnosis of COVID-19. The median infection prevalence ranged from 0.6% to 8.5%. PD-COVID+ patients had a median age of 74 and a disease duration of 9.4 years. Pooling all PD-COVID+ patients from included studies, 28.6% required hospitalization, 37.1% required levodopa dose increasing, and 18.9% died. The case fatality was higher in PD-COVID+ patients than the general population, with longer PD duration as a possible risk factor for worse outcome. Amantadine and vitamin D were proposed as potential protective factors. CONCLUSION: Available studies indicate a higher case fatality in PD patients affected by COVID-19 than the general population. Conversely, current literature does not definitively clarify whether PD patients are more susceptible to get infected. The potential protective role of vitamin D and amantadine is intriguing but deserves further investigation.