Do non-motor symptoms in Parkinson's disease differ from essential tremor before initial diagnosis? A clinical and scintigraphic study

Sleep and circadian rhythm dysfunctions in movement disorders beyond Parkinson's disease and atypical parkinsonisms

PURPOSE OF REVIEW

This review aimed to comprehensively outline sleep and circadian rhythm abnormalities in hyperkinetic movement disorders beyond Parkinson's disease and atypical parkinsonisms, including tremor, dystonia, choreiform movements, tics, and ataxia disorders.

RECENT FINDINGS

Insomnia, poor sleep quality, and excessive daytime sleepiness (EDS) are commonly reported in essential tremor, Wilson's disease, tics or Tourette's syndrome, and spinocerebellar ataxia (SCA). REM sleep behavior disorder (RBD) have been observed in Wilson's disease and SCA. A combination of REM and non-REM parasomnias, along with nocturnal stridor with the initiation of sleep and re-entering after awakening, are characterized by undifferentiated Non-REM and poorly structured N2 in anti-IgLON5 disease. Restless legs syndrome (RLS) has been reported commonly in SCAs. Sleep-related dyskinesia has been reported in ADCY5-related disease and GNAO1-related movement disorder.

SUMMARY

Sleep problems can manifest as a result of movement disorders, either through direct motor disturbances or secondary nonmotor symptoms. Medication effects must be considered, as certain medications for movement disorders can exacerbate or alleviate sleep disturbances. Distinguishing sleep problems in some diseases might involve pathognomonic symptoms and signs, aiding in the diagnosis of movement disorders.

Distinguishing essential tremor from Parkinson's disease: clinical and experimental tools

INTRODUCTION

Essential tremor (ET) and Parkinson's disease (PD) are the most common causes of tremor and the most prevalent movement disorders, with overlapping clinical features that can lead to diagnostic challenges, especially in the early stages.

AREAS COVERED

In the present paper, the authors review the clinical and experimental studies and emphasized the major aspects to differentiate between ET and PD, with particular attention to cardinal phenomenological features of these two conditions. Ancillary and experimental techniques, including neurophysiology, neuroimaging, fluid biomarker evaluation, and innovative methods, are also discussed for their role in differential diagnosis between ET and PD. Special attention is given to investigations and tools applicable in the early stages of the diseases, when the differential diagnosis between the two conditions is more challenging. Furthermore, the authors discuss knowledge gaps and unsolved issues in the field.

EXPERT OPINION

Distinguishing ET and PD is crucial for prognostic purposes and appropriate treatment. Additionally, accurate diagnosis is critical for optimizing clinical and experimental research on pathophysiology and innovative therapies. In a few years, integrated technologies could enable accurate, reliable diagnosis from early disease stages or prodromal stages in at-risk populations, but further research combining different techniques is needed.

Sleep Dysfunction in Movement Disorders: a Window to the Disease Biology

PURPOSE OF REVIEW

To comprehensively summarize the sleep pathologies associated with movement disorders, focusing on neurodegenerative diseases.

RECENT FINDINGS

Mounting evidence has further implicated both sleep and circadian disruption in the pathophysiology of many movement disorders. In particular, recent data illuminate the mechanisms by which poor sleep quality and circadian dysfunction can exacerbate neurodegeneration. In addition, anti-IgLON5 disease is a recently described autoimmune disease with various symptoms that can feature prominent sleep disruption and parasomnia. Many movement disorders are associated with sleep and circadian rhythm disruption. Motor symptoms can cause sleep fragmentation, resulting in insomnia and excessive daytime sleepiness. Many neurodegenerative movement disorders involve brainstem pathology in regions close to or affecting nuclei that regulate sleep and wake. Further, commonly used movement medications may exacerbate sleep concerns. Providers should screen for and address these sleep symptoms to improve function and quality of life for patients and caregivers.

Self-Reported Visual Complaints in People with Parkinson’s Disease: A Systematic Review

Background:

Scientific research increasingly focuses on visual symptoms of people with Parkinson’s disease (PD). However, this mostly involves functional measures, whereas self-reported data are equally important for guiding clinical care.

Objective:

This review provides an overview of the nature and prevalence of self-reported visual complaints by people with PD, compared to healthy controls.

Methods:

A systematic literature search was performed. Studies from three databases (PubMed, PsycInfo, and Web of Science) were screened for eligibility. Only studies that reported results of visual self-reports in people with idiopathic PD were included.

Results:

One hundred and thirty-nine eligible articles were analyzed. Visual complaints ranged from function-related complaints (e.g., blurred vision, double vision, increased sensitivity to light or changes in contrast sensitivity) to activity-related complaints (e.g., difficulty reading, reaching, or driving). Visual complaints were more prevalent in people with PD compared to healthy controls. The presence of visual complaints leads to a reduced quality of life (QoL). Increased prevalence and severity of visual complaints in people with PD are related to longer disease duration, higher disease severity, and off-state.

Conclusion:

A large proportion of people with PD have visual complaints, which negatively affect QoL. Complaints are diverse in nature, and specific and active questioning by clinicians is advised to foster timely recognition, acknowledgement, and management of these complaints.

Tremor Syndromes: An Updated Review

Tremor is the most commonly encountered movement disorder in clinical practice. A wide range of pathologies may manifest with tremor either as a presenting or predominant symptom. Considering the marked etiological and phenomenological heterogeneity, it would be desirable to develop a classification of tremors that reflects their underlying pathophysiology. The tremor task force of the International Parkinson Disease and Movement Disorders Society has worked toward this goal and proposed a new classification system. This system has remained a prime topic of scientific communications on tremor in recent times. The new classification is based on two axes: 1. based on the clinical features, history, and tremor characteristics and 2. based on the etiology of tremor. In this article, we discuss the key aspects of the new classification, review various tremor syndromes, highlight some of the controversies in the field of tremor, and share the potential future perspectives.

Sleep disorders in essential tremor: systematic review and meta-analysis

Sleep disorders are frequent in patients diagnosed with essential tremor (ET). The present review focuses on sleep disorders and the results of polysomnographic studies performed in patients with ET. For this purpose we performed a systematic review crossing the search term "essential tremor" with "sleep," "sleep disorders," "sleep disturbances" and "polysomnography," and with specific sleep disorders, according to the International Classification of the Sleep Disorders-Third Edition, using the PubMed, EMBASE, MEDLINE, and Web of Science Databases. The most frequent sleep problems reported by patients with ET were the bad quality of sleep and excessive daytime somnolence (the latter could be related to drugs commonly used for the treatment of ET). Probable rapid eye movement sleep behavior disorder, coexistent restless legs syndrome, insomnia, and nocturia were not infrequent complaints, while the presence of other sleep disorders in patients with ET was restricted to anecdotal reports or not described. Meta-analyses of previous reports showed that patients with ET (according to the PRISMA and MOOSE guidelines) showed higher scores in the Pittsburgh Sleep Quality Index and the Epworth Sleepiness Scale than controls and lower scores than those of patients diagnosed with Parkinson's disease. Studies using polysomnography in patients with ET are scarce and do not permit to establish valid conclusions regarding polysomnographic features in this disorder.

Sleep Disorders in Patients with Essential Tremor

PURPOSE OF THE REVIEW

Patients diagnosed with essential tremor (ET) report frequent sleep complaints. This review focuses on the main findings of studies addressing sleep features in patients diagnosed with ET, updating previously reported information. Bad quality of sleep and excessive daytime somnolence are very frequent in patients with ET, although the effects of the drugs used for the therapy of ET could contribute to these complaints. REM sleep behavior disorder, restless legs, insomnia, and nocturia are frequent complaints as well. There is a lack of studies addressing polysomnographic features of ET.

Non-motor symptoms in essential tremor, akinetic rigid and tremor-dominant subtypes of Parkinson's disease

Objectives

To compare non-motor symptoms (NMSs) among patients with essential tremor (ET), Parkinson’s disease (PD) subtypes (akinetic-rigid type (ART) and tremor-dominant type (TDT)), and healthy controls.

Patients and methods

This retrospective study included 129 participants, 72 PD (33 PD-ART, 33 PD-TDT, and 6 Mixed), 29 ET patients, and 28 controls. PD patients were assessed by the unified Parkinson’s disease rating scale (UPDRS), Hoehn, and Yahr scale (H&Y), while ET patients were evaluated by the Fahn Tolosa Marin Tremor Rating Scale. All subjects were evaluated by non-motor symptoms scale (NMSS) for NMSs and Beck depression inventory (BDI) for depression.

Results

PD subtypes groups, ET, and controls were age and gender-matched. Compared to controls, all PD, PD subtypes, and ET showed significantly worse most of NMSs (p<0.001) and depression. Compared to ET, all PD and PD-ART had significantly worse gastrointestinal (p = 0.002), urinary symptoms (p = 0.001, p = 0.003) and depression (p = 0.002) and PD-TDT worse depression, while ET patients showed worse memory/attention than PD subtypes. Total NMSS of ET is highly correlated to depression and moderately to tremor severity and age of onset, while total of NMSS is highly correlated to depression, disease severity, and disability.

Conclusion

The current study demonstrated several comparable domains of NMSs of PD subtypes and ET, except worse gastrointestinal and urinary symptoms among PD-ART. Identifying different NMSs profiles is important for predicting, better assessing, and tailoring management of ET and PD subtypes.

Olfactory dysfunction in essential tremor versus tremor dominant Parkinson disease

BACKGROUND

Essential tremor (ET) and tremor dominant Parkinson disease (TDPD) variant constitute the main causes of geriatric tremor which differentiation is not always an easy mission. The objective of this work was to study the olfactory performance in ET and PD patients for possible consideration as a differentiating biomarker.

METHODS

This study was performed on 36ET, 22 TDPD variant and 24 healthy controls subjects (HCS) submitted to extended n-butanol Sniffin' Sticks test (SST) and olfactory bulbs volumetry (OBV).

RESULTS

There were significant decreases in SST threshold, discrimination, identification and TDI variables in TDPD patients compared to ET and HCS. ET patients showed significant decrease in the same variables compared to HCS. Regarding OBV, there were significant decreases in TDPD patients compared to ET and HCS with nonsignificant difference between the 2-latter groups. Our results showed that TDI score of 25 can differentiate between TDPD and ET patients with sensitivity and specificity (94 %, 91 %) respectively.

CONCLUSION

Olfactory assessment is a rapid, safe, and easily applicable biomarker that could differentiate TDPD from ET in doubtful cases.

Distinct non-motor features of essential tremor with head tremor patients

BACKGROUND

There have been few comprehensive scale studies on the non-motor symptoms (NMS) of patients with essential tremor (ET) with head tremor (ETh) and those with ET without head tremor (ETol). We aimed to explore the motor symptoms and NMS of these two subgroups.

METHODS

We enrolled 199 patients with ET (125, ETol; 74 ETh) and 132 healthy controls. We evaluated motor symptoms using the Fahn-Tolosa-Marin Tremor Rating Scale (TRS) and NMS using the Non-Motor Symptom Scale (NMSS). We compared NMSS scores and the prevalence of each NMS between the patient subgroups. Finally, we conducted a logistic regression analysis of the correlation between head tremor and NMS severity, as well as other determinants.

RESULTS

There were no significant between-subgroup differences in demographic characteristics. Further, they presented similar tremor clinical manifestation; however, the ETh subgroup showed a higher prevalence of rest tremor, feeling of sadness, forgetting things or events, and swallowing difficulty, as well as TRS scores, compared with the ETol subgroup. Both patient subgroups showed high scores and prevalence (>50%) in difficulty falling asleep. Logistic regression analysis indicated age as a tremor severity determinant; further, head tremor and tremor severity were NMS determinants.

CONCLUSION

Both patient subgroups presented various NMS including sleep disturbances, cognitive deficits, and affective disorders. The ETh subgroup showed a high prevalence of certain NMS aspects including memory and affective disorder; further, they had aggravated NMS. ET with both upper limb tremor and head tremor may be regarded as a more severe clinical subtype.

Clinical Profile of Non-Motor Symptoms in Patients with Essential Tremor: Impact on Quality of Life and Age-Related Differences

Background

Identifying the clinical phenotypes of non-motor symptoms (NMSs) of essential tremor (ET) among different populations is necessary due to their impact on the quality of life (QoL). This study aimed to investigate the clinical phenotype and impact of NMSs on QoL in Egyptian patients with ET.

Methods

Thirty ET patients were compared to 30 matched controls. Subjects were evaluated by the Fahn-Tolosa-Marin Tremor Rating Scale, Non-Motor Symptoms Scale (NMSS), Montreal Cognitive Assessment, Hamilton Anxiety Rating Scale, Beck Depression Inventory, Pittsburgh Sleep quality Index, and the Short Form 36 Health Survey Questionnaire. Both groups were divided into two subgroups of younger (<45 years, 14 patients) and older age (>45 years, 16 patients) groups, to investigate age-related differences.

Results

ET patients showed significantly worse cognition, depression, anxiety, sleep and NMSS domains (p < 0.001), compared to controls, that negatively affected and predicted QoL. Older patients had more cognitive impairment (p = 0.003) and worse sleep/fatigue (p = 0.032) and sexual functions (p = 0.006), compared to younger group.

Discussion

The study supports that NMSs are integral part of ET, negatively affect QoL, and similarly affect younger and older patients. Therefore, NMSs should be explored for proper care of ET patients.

Essential pitfalls in "essential" tremor

Although essential tremor has been considered the most common movement disorder, it has largely remained a diagnosis of exclusion: many tremor and nontremor features must be absent for the clinical diagnosis to stand. The clinical features of "essential tremor" overlap with or may be part of other tremor disorders and, not surprisingly, this prevalent familial disorder has remained without a gene identified, without a consistent natural history, and without an acceptable pathology or pathophysiologic underpinning. The collective evidence suggests that under the rubric of essential tremor there exists multiple unique diseases, some of which represent cerebellar dysfunction, but for which there is no intrinsic "essence" other than a common oscillatory behavior on posture and action. One approach may be to use the term essential tremor only as a transitional node in the deep phenotyping of tremor disorders based on historical, phenomenological, and neurophysiological features to facilitate its etiologic diagnosis or serve for future gene- and biomarker-discovery efforts. This approach deemphasizes essential tremor as a diagnostic entity and facilitates the understanding of the underlying disorders to develop biologically tailored diagnostic and therapeutic strategies. © 2017 International Parkinson and Movement Disorder Society.

A comparison between rate of nonmotor symptom development in essential tremor and Parkinson's disease

In the last decade our perspective on essential tremor (ET) as a pure motor system disorder has begun to change. By virtue of recent studies of nonmotor symptoms (NMSs) that are used to characterize Parkinson's disease (PD), these symptoms have also been added to the definition of ET. There is increasing evidence to suggest that ET might not be as benign and monosymptomatic as we previously thought. The aim of this study was to evaluate nonmotor symptoms in ET, and to compare them with PD. We studied 37 ET and 23 PD patients. Tremor rate was evaluated using the Fahn-Tolosa-Marin tremor rating scale (FTM-TRS) in ET patients. The patients with PD were scored for motor symptoms using the unified Parkinson's disease rating scale (UPDRS)-III and the Hoehn-Yahr scale. Cognitive functions were assessed with the Montreal Cognitive Assessment (MoCA) test. NMSs were evaluated with the nonmotor symptoms questionnaire (NMSQuest). In the ET group, the most common NMSs were forgetting things, feeling sad, nocturia, urgency, and difficulty concentrating. The mean NMSQuest score was 8.43 ± 4.14 in the ET group and 14.06 ± 5.44 in the PD group (p value <0.001). However, except for 12 items in NMSQuest, in comparing items one by one there was no statistical difference between them. The mean MoCA total score was 17.81 ± 4.56 in the ET group and 17.08 ± 4.08 in the PD group (p value 0.675). There were no significant differences in MoCA subgroup scores. Evaluation of nonmotor symptoms in ET may help us to understand this emerging definition of ET. This study contributes evidence toward this new concept.

Motor and Non-motor Features: Differences between Patients with Isolated Essential Tremor and Patients with Both Essential Tremor and Parkinson's Disease

BACKGROUND

Patients with essential tremor (ET) who develop Parkinson's disease (PD) (i.e., ET→PD) may differ with respect to motor features (MFs) and non-motor features (NMFs) from patients with isolated ET. Few studies have assessed this issue.

METHODS

In this retrospective chart review, we analyzed data on MFs and NMFs of 175 patients, including 54 ET→PD and 121 ET, actively followed in the Athens University 1st Neurology Department.

RESULTS

Significantly more ET→PD than ET patients reported asymmetric tremor at ET onset (68.5% vs. 14.9%, p<0.001). Significantly more ET than ET→PD patients had head tremor (43.5% vs. 13.2%, p<0.001) and cerebellar signs (41.3% vs. 9.3%, p<0.001). More ET than ET→PD patients reported hearing impairment (65.3% vs. 28.3%, p<0.001) and restless legs syndrome (34.8% vs. 3.7%, p<0.001). Conversely, a larger proportion of ET→PD than ET patients reported rapid eye movement behavior disorder (51.9% vs. 10.0%, p<0.001), constipation (67.9% vs. 36.4%, p<0.001), and olfactory dysfunction (83.3% vs. 36.4%, p<0.001).

DISCUSSION

The subset of ET→PD patients may have distinct MFs and NMFs that should be assessed further for the possible predictive value for the emergence of PD.

Change in Non-motor Symptoms in Parkinson's Disease and Essential Tremor Patients: A One-year Follow-up Study

BACKGROUND

Non-motor symptoms (NMS) in Parkinson's disease (PD) differ from those in essential tremor (ET), even before a definitive diagnosis is made. It is not clear whether patient's knowledge of the diagnosis and treatment influence their subsequent reporting of NMS.

METHODS

1 year after a clinical and instrumental diagnosis, we compared the motor impairment (Movement Disorders Society (MDS)-Unified Parkinson's Disease Rating Scale-III) and non-motor symptoms (NMSQuest) in PD (n = 31) and ET (n = 21) patients.

RESULTS

PD patients reported more NMS than did the ET patients (p = 0.002). When compared to their baseline report, at follow-up, PD patients reported less nocturia (p = 0.02), sadness (p = 0.01), insomnia (p = 0.02), and restless legs (p = 0.04) and more nausea (p = 0.024), unexplained pain (p = 0.03), weight change (p = 0.009), and daytime sleepiness (p = 0.03). When compared to their baseline report, ET patients reported less loss of interest (p = 0.03), anxiety (p = 0.006), and insomnia (p = 0.02). Differences in reported weight change (p<0.0001) and anxiety (p = 0.001) between PD and ET patients were related to pharmacological side effects or to a reduction in the ET individuals.

DISCUSSION

The reporting of NMS is influenced by subjective factors, and might vary with the patient's knowledge of the diagnosis or the effectiveness of treatment.

Ultrasonographic (TCS) and clinical findings in overlapping phenotype of essential tremor and Parkinson's disease (ET-PD)

BACKGROUND

Essential tremor (ET) and Parkinson's disease (PD) are considered distinct disorders. The aim of the study was to look for a link or any distinguishing features by transcranial sonography (TCS), together with the clinical examination findings in a group of patients with overlapping phenotype of ET and PD (ET-PD).

METHODS

A prospective observational case-control study was carried out from the 3rd January 2011 until 30th January 2013 at the Hospital of Lithuanian University of Health Sciences. The final study group consisted of 15 patients with ET-PD, 116 patients with ET-only and 141 patients with PD-only. The control group included 101 subjects. Clinical diagnosis was of a diagnostic standard.

RESULTS

The main ultrasonographic findings in the ET-PD group were similar to those of the PD-only: hyperechogenicity of the substantia nigra (66.7%, p < 0.001) and nuclei raphe interruptions/absence (38.5%, p < 0.001). The single distinguishing TCS finding in ET-PD group was a lentiform nucleus hyperechogenicity (26.7%), however this was only significant when compared to controls (p = 0.006). An asymmetrical onset of symptoms (73.3%) in ET-PD group was characteristic to PD-only. The ET-PD patients had the longest disease duration (median 6 years, p < 0.001), the most frequent rate of positive family history (53.3%, p = 0.005), rather low prevalence of cogwheel rigidity (26.7%, p < 0.001), and higher mean Hoehn & Yahr scores compared to PD-only (2.6 ± 0.8 vs. 1.8 ± 0.8, p = 0.012).

CONCLUSIONS

The main TCS findings of the present study in patients with overlapping ET-PD phenotype were similar to the PD-only group. The highest positive family history rate among ET-PD patients indicates a strong hereditary predisposition and needs genetic underpinnings. Some ET patients, who look like they may be developing co-morbid PD clinically, may have an alternative diagnosis for Parkinsonism, which could be delineated by TCS examination.

Patient-reported Needs, Non-motor Symptoms, and Quality of Life in Essential Tremor and Parkinson's Disease

BACKGROUND

Non-motor symptoms, quality of life, service needs, and barriers to care of individuals with movement disorders are not well explored. This study assessed these domains within a sample of individuals with essential tremor (ET) and Parkinson's disease (PD).

METHODS

A survey exploring symptoms, needs, and barriers to care was disseminated to a convenience sample (N = 96) of individuals with a primary diagnosis of ET (N = 19) or PD (N = 77).

RESULTS

Similarities in overall quality of life and impact on daily functioning were found across individuals with ET and PD. Noteworthy differences included endorsement of different types of service needs and utilization patterns and fewer non-motor symptoms reported among those with ET (M = 6.1, SD = 2.4) than those with PD (M = 10.4, SD = 3.4). Non-motor symptoms significantly impacted movement disorder-related quality of life for both diagnostic groups, but this relationship was stronger for individuals with ET, t(12) = 3.69, p = 0.003, β = 0.73 than with PD, t(56) = 4.00, p<0.001, β = 0.47. Individuals with ET also reported higher rates of stigma (31.6% vs. 7.8%) and greater impact of non-motor symptoms on emotional well-being, R (2) = 0.37, F(1, 13) = 7.17, p = 0.020.

DISCUSSION

This is the first study to describe and compare the needs, barriers to care, and impact on quality of life of two distinct movement disorder groups. Our results support the recent efforts of the field to identify interventions to address the non-motor symptoms of movement disorders and indicate need for greater appreciation of the specific differences in symptoms and quality of life experienced across movement disorder diagnoses.