Philadelphia Geriatric Morale Scale in essential tremor: a population-based study in three Spanish communities

[Essential tremor: are we just splitting hairs? Non-motor symptoms and essential tremor-plus]

INTRODUCTION

The existence of non-motor symptoms in essential tremor (ET) and the appearance of a new condition, ET-plus, are two controversial issues.

AIMS

To offer a review of the current status of these two topics.

DEVELOPMENT

We performed an analysis of the studies conducted on non-motor symptoms in ET and of the articles for and against the use of the term ET-plus.

CONCLUSIONS

Non-motor symptoms have gained increased recognition as a feature accompanying ET. Several studies have documented its presence compared to matched controls. It is not clear, however, whether these non-motor symptoms would be part of the spectrum of ET symptoms (a primary phenomenon) or whether they would be symptoms that appear as a consequence of the physical or psychological disability produced by the clinical signs and symptoms of ET itself (a secondary phenomenon). For the time being, their evaluation and treatment are not included within the standard assessment of patients with ET. In view of the heterogeneous phenotype, the term ET-plus aims to improve phenotypic homogeneity for genetic or therapeutic studies. Yet, there is no pathological basis, and epidemiological, genetic and therapeutic research studies have numerous drawbacks. In the absence of clear objective biomarkers, distinguishing between ET and ET-plus by clinical distinction alone is very complex. We should be cautious about using new terms that are not yet backed by sound scientific evidence.

Essential tremor

Essential tremor (ET) is a chronic and progressive neurologic disease. Its central and defining clinical feature is a 4-12Hz kinetic tremor, that is, tremor that occurs during voluntary movements such as drinking from a cup or writing. Patients may also exhibit a range of other tremors-postural, rest, intention, additional motor features (e.g., mild gait ataxia, mild dystonia), as well as nonmotor features. The disease itself seems to be a risk factor for other degenerative diseases such as Alzheimer's disease and Parkinson's disease. Both genetic and toxic environmental factors have been explored as etiologic factors. In addition to a growing appreciation of the presence of clinical, etiologic, and pathologic heterogeneity, there is some support for the notion that ET itself may not be a single disease, but may be a family of diseases whose central defining feature is kinetic tremor of the arms, and which might more accurately be referred to as "the essential tremors." Recent research has increasingly placed the seat of the disease in the cerebellum and cerebellar system and identified a host of neurodegenerative changes within the cerebellum, indicating that this progressive disorder is likely degenerative.

A Review on Wearable Technologies for Tremor Suppression

Tremor is defined as a rhythmic, involuntary oscillatory movement of a body part. Although everyone exhibits a certain degree of tremor, some pathologies lead to very disabling tremors. These pathological tremors constitute the most prevalent movement disorder, and they imply severe difficulties in performing activities of daily living. Although tremors are currently managed through pharmacotherapy or surgery, these treatments present significant associated drawbacks: drugs often induce side effects and show decreased effectiveness over years of use, while surgery is a hazardous procedure for a very low percentage of eligible patients. In this context, recent research demonstrated the feasibility of managing upper limb tremors through wearable technologies that suppress tremors by modifying limb biomechanics or applying counteracting forces. Furthermore, recent experiments with transcutaneous afferent stimulation showed significant tremor attenuation. In this regard, this article reviews the devices developed following these tremor management paradigms, such as robotic exoskeletons, soft robotic exoskeletons, and transcutaneous neurostimulators. These works are presented, and their effectiveness is discussed. The article also evaluates the different metrics used for the validation of these devices and the lack of a standard validation procedure that allows the comparison among them.

Essential tremor and the cerebellum

Essential tremor (ET) is a progressive and highly prevalent neurologic disease. Along with the tremors, mild to moderate gait ataxia and other signs of cerebellar dysfunction may occur (i.e., subtle saccadic eye movement abnormalities and abnormalities of motor timing) as well as cognitive features, some of which may be due to cerebellar dysfunction. Numerous neuroimaging studies indicate the presence of functional, metabolic, and structural abnormalities in the cerebellum of a patient with ET. In tandem with these clinical and imaging studies, which were gathering increasing support for the notion that the cerebellum and/or cerebellar systems seemed to be at the root of ET, a growing postmortem literature is for the first time beginning to identify microscopic abnormalities in the ET brain, most of which are centered on the Purkinje cells and connected neuronal populations, and are likely to be degenerative. In terms of treatment, most of these pharmacotherapeutic agents serve to enhance GABAergic neurotransmission, further bolstering the notion that ET may very well be a disorder with a primary Purkinje cell dysfunction resulting in reduced cerebellar cortical inhibition. Similarly, the interruption of presumably abnormal cerebellar outflow pathways to the thalamus is the mechanism of deep-brain stimulation surgery, which is highly effective in treating ET.

Nonmotor Symptoms in Essential Tremor and Other Tremor Disorders

Tremor, like dystonia, is a term used at the phenomenological, syndromic, and aetiopathological level. Parkinsonian, essential, and dystonic tremor are the three most common tremor diagnoses encountered in clinical practice. Investigation of nonmotor symptoms in essential tremor and dystonic tremor syndromes is significantly hampered by the lack of clear clinical diagnostic criteria for these groups at a syndromic level, and the absence of biomarkers which allow definitive diagnosis at an aetiopathological level. Much work is needed in clarifying the motor features of these disorders in order to allow delineation of the nonmotor features of the most common tremor syndromes. With this limitation in mind, this chapter reviews what is known about nonmotor symptoms in these two tremor types. The final sections deal with nonmotor symptoms observed in patients with lesional tremor, thankfully a much more clearly defined albeit less common group of patients.

Chinese version of the Aging Perceptions Questionnaire (C-APQ): assessment of reliability and validity

OBJECTIVES

To assess the reliability and validity of the Chinese version of Aging Perceptions Questionnaire (C-APQ).

METHOD

Participants aged 65 years and over were recruited from February 2012 to November 2012. The Aging Perceptions Questionnaire was translated into Chinese version professionally. Content validity was examined by a panel of seven experts; item reliabilities were assessed by test-retest; internal consistency was assessed by Cronbach's α coefficient; half of the sample (N = 379) was selected to explore factorial structure of the C-APQ by exploratory factor analysis (EFA) and another half of the sample (N = 379) was selected to confirm the findings from the EFA by confirmatory factor analysis (CFA). Statistical package SPSS version 18.0 and Amos 17.0 were used for the analysis.

RESULTS

The Cronbach's α coefficient of the C-APQ was 0.884. The test-retest reliability was satisfactory, with all intraclass correlation coefficients greater than 0.4. The overall content validity index was greater than 0.99. Seven factors (timeline acute/chronic, timeline cyclical, emotional representations, control positive, control negative, consequences positive and consequences negative) were identified in EFA and confirmed in CFA.

CONCLUSION

The C-APQ could be a reliable and a valid measure of the self-perceptions of aging in the elderly in China, which may help to improve the life quality and extend longevity of the elderly.

Non-Motor Symptoms of Essential Tremor Are Independent of Tremor Severity and Have an Impact on Quality of Life

Background

Several publications have focused on accompanying non-motor symptoms (NMS) in essential tremor (ET) patients; however, it remains unclear if NMS are an intrinsic part of the disease or secondary phenomena. We present the results of several neuropsychiatric tests and their impact on quality of life (QoL) in community-dwelling patients with ET.

Methods

Participants were recruited via a newspaper article about ET published in the local media and on the internet. All participants completed several standard neuropsychiatric tests, including those that assess QoL. To compare differences between cases and controls, Student’s t-tests with Bonferroni-Holm post hoc tests were performed. Spearman’s correlation coefficients were also calculated.

Results

We enrolled 110 patients with definite or probable ET. Highly significant changes were observed for apathy, anxiety, and cognition and negatively impacted QoL. Most aberrations were independent of tremor severity and duration.

Discussion

The significant neuropsychiatric deficits and reduced QoL demonstrate a degree of illness that appears to be a non-motor phenotype rather than a secondary effect of ET. In the future, NMS should carefully be explored in ET patients as they may have an impact on QoL and treatment.

Self-rated health and risk of incident essential tremor: A prospective, population-based study (NEDICES)

BACKGROUND

Essential tremor (ET), a highly-prevalent, progressive, aging-associated neurological disease, poses a significant public health challenge. Aside from its associated motor features, the disease affects cognition in some patients, mood, and morale, and has been associated with increased risk of mortality in the elderly. Studies have not investigated the relationship between self-rated health and risk of ET. We determined whether baseline poor self-rated health was associated with increased risk of incident ET.

METHODS

In this prospective, population-based study of people ≥65 years of age, subjects were evaluated at baseline and 3 years later. At baseline, subjects were asked to rate their health using a single-item health question. Hazard ratios (HR) of ET according to baseline self-rated health (very good, good, fair, poor, and very poor) were estimated with Cox models.

RESULTS

The 3853 subjects had a median follow-up duration of 3.2 years. There were 82 incident ET cases. Compared to subjects who rated their health as good or very good, the risk of ET was increased for subjects who rated their health as fair (HR = 1.69, p = 0.03), and for subjects who rated their health as poor or very poor (HR = 2.12, p = 0.02). In a fully adjusted model, the risk remained increased for subjects who rated their health as poor or very poor (HR = 2.34, p = 0.01).

CONCLUSIONS

Subjects rating their health as poor/very poor at baseline were at increased risk of incident ET at follow-up. Premotor and/or early motor symptoms of ET could negatively influence self-perceptions of health status.

Polypharmacy in the Elderly: A Marker of Increased Risk of Mortality in a Population-Based Prospective Study (NEDICES)

BACKGROUND

Little information is available on the potential association between polypharmacy and risk of mortality.

OBJECTIVE

To determine in a population-based study whether polypharmacy is associated with increased risk of mortality in elderly persons.

METHODS

In this population-based, prospective study of 5,052 people aged 65 years and older (Neurological Disorders in Central Spain), current medications were recorded. Cox proportional hazards models, adjusted for sociodemographics and comorbidity factors, were used to assess the risk of death up to 13.3 years later, comparing the polypharmacy group (≥6 drugs) to those who were taking 1-5 drugs and those in a nonmedicated group (0 drugs).

RESULTS

Out of 5,052 participants, 2,550 (50.5%) died over a median follow-up of 6.5 years, including 361 (28.8%) deaths among 931 nonmedicated participants, 1,946 (51.4%) deaths among 3,787 participants taking 1-5 drugs daily, and 243 (72.8%) among 334 participants on polypharmacy. In an unadjusted Cox model, risk of mortality was increased in participants on polypharmacy [hazard ratio (HR) = 2.78, 95% confidence interval [CI]: 2.36-3.27, p < 0.001) and in those taking between 1 and 5 drugs (HR = 1.47, 95% CI: 1.31-1.64, p < 0.001) versus those who were nonmedicated (reference group). In a Cox model that adjusted for a variety of demographic factors and comorbidities, HR remained increased in participants on polypharmacy (HR = 1.83, 95% CI: 1.51-2.21, p < 0.001).

CONCLUSION

This study provides evidence that polypharmacy is associated with increased risk of mortality in elderly people. The extent to which polypharmacy is the proximate cause rather than a marker of this increase risk remains to be determined.

The Non-motor Features of Essential Tremor: A Primary Disease Feature or Just a Secondary Phenomenon?

Essential tremor (ET) is a pathologically heterogeneous neurodegenerative disorder with both motor and increasingly recognized non-motor features. It is debated whether the non-motor manifestations in ET result from widespread neurodegeneration or are merely secondary to impaired motor functions and decreased quality of life due to tremor. It is important to review these features to determine how to best treat the non-motor symptoms of patients and to understand the basic pathophysiology of the disease and develop appropriate pharmacotherapies. In this review, retrospective and prospective clinical studies were critically analyzed to identify possible correlations between the severities of non-motor features and tremor. We speculated that if such a correlation existed, the non-motor features were likely to be secondary to tremor. According to the current literature, the deficits in executive function, attention, concentration, and memory often observed in ET are likely to be a primary manifestation of the disease. It has also been documented that patients with ET often exhibit characteristic personality traits. However, it remains to be determined whether the other non-motor features often seen in ET, such as anxiety, depression, and sleep disturbances are primary or secondary to motor manifestations of ET and subsequent poor quality of life. Finally, there is evidence that patients with ET can also have impaired color vision, disturbances of olfaction, and hearing impairments, though there are few studies in these areas. Further investigations of large cohorts of patients with ET are required to understand the prevalence, nature, and true significance of the non-motor features in ET.

The cognitive side of essential tremor: what are the therapeutic implications?

While essential tremor (ET) has traditionally been categorized as a pure motor disease, cross-sectional and longitudinal studies of cognition in ET have demonstrated that these patients may have cognitive dysfunction. Recent epidemiological studies demonstrate an association between ET (particularly with onset after age 65) and increased risk for cognitive impairment and dementia. Although existing studies have generally conceptualized cognitive changes in ET as consistent with a 'frontosubcortical' or 'corticocerebellar' profile, results from these same studies suggest that cognitive impairment in ET may in fact be heterogeneous. Furthermore, the underlying mechanisms remain uncertain. Cognitive changes could be a byproduct of the cerebellar dysfunction of ET itself; alternately, they may be a feature of concomitant neurodegenerative diseases that have been associated in several studies with ET, including Alzheimer's disease, Parkinson's disease or progressive supranuclear palsy. While the study of cognitive dysfunction in ET has received research attention in recent years, the results of these studies have not been translated into the clinical domain and clinical practice. This review first summarizes the current literature on the potential relationships between ET and cognitive change. We then suggest areas of further clinical evaluation and treatment; these suggestions are directed at physicians caring for ET patients who may demonstrate or complain of cognitive impairment. As we discuss, clinicians should ideally screen ET patients for possible signs or symptoms of cognitive impairment in addition to assessing for psychiatric comorbidity and quality of life. These recommendations are in contrast to most current clinical practice, which does not routinely include such assessment among ET patients. To our knowledge, there have been no pharmacotherapeutic trials to date of any agent for cognitive change associated with ET. We believe that studies for this indication are now called for. Future efforts in this direction will also need to take into account the pathobiology of cognitive changes in ET, which itself is an area that is ripe for future investigations.

Blood harmane (1-methyl-9H-pyrido[3,4-b]indole) concentration in essential tremor cases in Spain

BACKGROUND

Environmental correlates for essential tremor (ET) are largely unexplored. The search for such environmental factors has involved the study of a number of neurotoxins. Harmane (1-methyl-9H-pyrido[3,4-b]indole) is a potent tremor-producing toxin. In two prior case-control studies in New York, we demonstrated that blood harmane concentration was elevated in ET patients vs. controls, and especially in familial ET cases. These findings, however, have been derived from a study of cases ascertained through a single tertiary referral center in New York.

OBJECTIVE

Our objective was to determine whether blood harmane concentrations are elevated in familial and sporadic ET cases, ascertained from central Spain, compared to controls without ET.

METHODS

Blood harmane concentrations were quantified by a well-established high performance liquid chromatography method.

RESULTS

The median harmane concentrations were: 2.09 g(-10)/ml (138 controls), 2.41 g(-10)/ml (68 sporadic ET), and 2.90 g(-10)/ml (62 familial ET). In an unadjusted logistic regression analysis, log blood harmane concentration was not significantly associated with diagnosis (familial ET vs. control): odds ratio=1.56, p=0.26. In a logistic regression analysis that adjusted for evaluation start time, which was an important confounding variable, the odds ratio increased to 2.35, p=0.049.

CONCLUSIONS

Blood harmane levels were slightly elevated in a group of familial ET cases compared to a group of controls in Spain. These data seem to further extend our observations from New York to a second cohort of ET cases in Spain. This neurotoxin continues to be a source of interest for future confirmatory research.

[Neuropsychiatric disturbances in essential tremor]

This review focuses on the neuropsychiatric manifestations (personality disturbances, depressive symptoms, cognitive impairment and dementia), which have been described in this last decade in patients with essential tremor. We compared the data derived from the Neurologic Disorders in Central Spain (NEDICES) study, a prospective population-based survey, with those derived from the literature. The traditional view of essential tremor as a mono-symptomatic condition characterized by action tremor is now changing. First, it is known that many patients also have other motor manifestations apart from tremor (e.g., ataxic gait). Second, in the last years, the presence of a variety of non-motor neuropsychiatric features has been described. Mild cognitive changes (especially executive dysfunction) have been documented in several independent studies. Further, two population-based studies have demonstrated an association between essential tremor with mild cognitive impairment and dementia. Psychiatric manifestations include specific personality traits, anxiety, social phobia, and depressive symptoms. Taking together, the neuropsychiatric dysfunction pattern and the new data on neuropathology of essential tremor suggest that this disease is a neurodegenerative cerebellar disorder and let us to question the classical concept of essential tremor as a benign mono-symptomatic disorder.

Factors associated with receptivity to deep brain stimulation surgery among essential tremor cases

BACKGROUND

A sizable proportion of essential tremor (ET) patients suffer from medically-refractory ET. Although deep brain stimulation (DBS) surgery is a safe and highly effective treatment, it may be under-utilized. We are unaware of studies that assess ET patients' attitudes toward DBS surgery and the factors that motivate them toward or away from such surgery.

METHODS

ET cases, enrolled in an ongoing clinical-pathological study, underwent an in-person evaluation. They were asked "What is the likelihood that you would allow yourself to have DBS surgery?", thus rating their 'surgical receptivity' from 0 to 100.

RESULTS

One-third (47/146, 32.2%) of ET cases reported that they would consider DBS surgery. In univariate analyses, younger age (p = 0.017), self-reported embarrassment (p = 0.001), more depressive symptoms (p = 0.008), more dysthymia (p = 0.029), higher total tremor score (marginal p = 0.13) and lower burden of medical comorbidity (marginal p = 0.16) were associated with greater surgical receptivity. In multivariate logistic regression models, only self-reported embarrassment (p = 0.006) and, marginally, younger age (p = 0.059) were independently associated with surgical receptivity.

CONCLUSIONS

We identified a number of factors that were associated with increased receptivity to DBS surgery. Interestingly, psychosocial variables (dysthymia, depressive symptoms, self-reported embarrassment) featured prominently among these factors; indeed, self-reported embarrassment was the most robust factor. Tremor severity, though associated in univariate analyses with increased surgical receptivity, was not as robust of a predictor as was self-reported embarrassment. Future studies, which are community-based as well as those which also assess the patient's level of understanding about DBS will further add to the literature on this topic.

It is time to remove the 'benign' from the essential tremor label

In recent years, studies of essential tremor (ET) have demonstrated that the disease is associated with functionally-relevant cognitive abnormalities, a mood disturbance and other psychiatric co-morbidities, a functionally significant gait disorder, hearing deficits, and a variety of types of tremor. The tremor has been shown to be progressive in nature and quite disabling for a large number of sufferers. Also, recent clinical-epidemiological studies have linked prevalent ET to other neurodegenerative diseases and at least one study has demonstrated an increased risk of mortality in an ET cohort. While many of these studies are derived from clinic-based samples, population-based studies have also substantiated these findings, suggesting that even in the general population, the disease is associated with disability and with co-morbidity. Based on these available studies, it would seem inaccurate to append the word "benign" to ET. Not unlike the word "essential" itself, the word "benign" is an antiquated and outdated term that reflects an era where little was understood about ET. Historically, the general doctors who frequently encountered the disorder would educate patients that it was a benign, non-progressive condition not associated with any co-morbidity or risk of long-term worry. This notion, conceived by prior generations of physicians, is now known to be inaccurate. It is therefore our recommendation that the medical community open the dialog to consider formally discontinuing this nosology ("benign essential tremor") and to adopt the use of the term "essential tremor." Use of the word "benign" is a mischaracterization of the disease course, and could be prove misleading especially in the evolving doctor-patient relationship. In those cases with currently-mild tremor, the nosology "mild essential tremor" would be a more accurate reflection of disease.

Assessment of factors influencing morale in the elderly

Background

We examined the relationship between morale measured by the Philadelphia Geriatric Morale Scale (PGC) and disability, social support, religiosity, and personality traits. Instruments predicting morale were then tested against PGC domains.

Methods

The study utilized a cross-sectional survey with a multistage cluster sampling design. Instruments used were disability (disease burden; WHO Disability Score-II, WHODAS-II), social support (Duke Social Support Scale, DUSOCS; Lubben Social Network Scale, LSNS-6; Medical Outcomes Study Social Support Survey, MOS-SSS), religiosity (Revised Intrinsic-Extrinsic Religious Orientation Scale, I/E-R), and personality (Ten-Item Personality Inventory, TIPI). These were plotted as bar charts against PGC, resolved with one-way ANOVA and Kruskal-Wallis tests, then corrected for multiple comparisons. This process was repeated with PGC domains. Contribution of factors was modeled using population attributable risk (PAR) and odds ratios. Effect of confounders such as gender, age, and ethnicity were checked using binary logistic regression.

Results

All instruments showed clear relationships with PGC, with WHODAS-II and DUSOCS performing well (ANOVA p<0.001). For PGC domains, attitude toward aging and lonely dissatisfaction trended together, while agitation did not. PAR, odds ratios, and Exp(β) were disability (WHODAS-II: 28.5%, 3.8, 2.8), social support (DUSOCS: 28.0%, 3.4, 2.2), religiosity (I/E-R: 21.6%, 3.2, 2.1), and personality (TIPI: 27.9%, 3.6, 2.4). Combined PAR was 70.9%.

Conclusions

Disability, social support, religiosity, and personality strongly influence morale in the elderly. WHODAS-II and DUSOCS perform best in measuring disability and social support respectively.

Methods and design of the baseline survey of the neurological disorders in Salamanca (NEDISA) cohort: a population-based study in Central-Western Spain

BACKGROUND

To describe the design of the baseline assessment of an epidemiological study of elderly persons living in Salamanca, central-western Spain: the Neurological Diseases in Salamanca (NEDISA) study. We assessed the epidemiology of stroke, cognitive disorders, essential tremor (ET), Parkinson's disease (PD) and restless legs syndrome.

METHODS

In phase 1 (February 1 to May 31, 2007), 4 neurologists and 2 trained general physicians examined and performed phlebotomy on all participants. In phase 2 (June 1, 2007, to June 1, 2008), the participants were reexamined and had a complete neuropsychological assessment. Neuroimaging was performed in participants with cognitive disorders, ET and PD.

RESULTS

The registered study population consisted of 1,077 individuals, but 45 people were ineligible (address change, refusals or death), leaving a final sample of 1,032 (95.8%). The main demographic data on the 1,032 participants (408 men, 624 women) are provided.

CONCLUSIONS

Most of the registered study population was enrolled, and this may have been due to the close relationship between NEDISA researchers and the general physicians in the area of study. The NEDISA study will likely improve our knowledge of prevalence rates of the neurological diseases chosen for study as well as the set of risk factors that predispose individuals in Spain to these disorders.

The psychosocial burden of essential tremor in an outpatient- and a community-based cohort

BACKGROUND AND PURPOSE

To compare psychosocial burden in patients with essential tremor (ET) in an outpatient (OPC)- and a community-based cohort (CBC).

METHODS

A sample of outpatients of a tertiary referral center (n = 180) and a community-based sample (n = 100) with ET were asked for study participation. Psychosocial aspects were assessed by a questionnaire on psychosocial aspects of ET, neuropsychological scales, quality of life, personality traits, and coping strategies.

RESULTS

One hundred and seven patients of the OPC and 90 individuals of the CBC participated and their results are descriptively presented. Statistical analysis was restricted to 38 pairs of OPC and CBC individuals matched for age, sex, and tremor severity. One-third of these individuals reported a profound impairment in everyday or professional life. Neuropsychological scales showed a severe depression in 8% of the individuals and pathologic values for the general level of psychiatric symptoms in 26%. The main coping strategy was 'active problem-orientated coping'. Patients of the OPC perceived a more severe impact of ET on their life. Multivariate analysis revealed the Beck Depression Inventory score as the only predictive factor for the outcome variables, physical and mental component scores, of the SF-12 health survey.

CONCLUSIONS

ET causes a significant psychosocial impairment, which does depend on symptom severity but also on mood with depression as the main driving factor and other so far undetermined factors.

Essential tremor

Essential tremor (ET) is among the most common neurological disorders. This chapter reviews the epidemiology, clinical features, and pathophysiology of ET. The defining feature is a kinetic tremor of the arms. Patients often have a postural tremor as well. Other body regions may also be involved (especially the head). The severity of tremor may range from mild cases in population settings to more severe cases in treatment settings. Motor features aside from tremor have been described in ET, including tandem gait difficulty. Mild cognitive changes (especially executive dysfunction) have been documented in many studies as well. Despite being regarded as one of the most common hyperkinetic movement disorders, establishing a precise prevalence has been difficult, yet the prevalence among persons aged 40 and older seems to be 4% or higher. There are numerous examples of families in which the disease appears to be inherited yet genetic studies have not progressed to the point where ET genes have been identified. There is also a growing understanding that environmental factors are likely to contribute to the etiology of ET. More recent postmortem studies have helped localize the possible source of ET to structural alterations in the cerebellum and its connecting pathways.

Low morale is associated with increased risk of mortality in the elderly: a population-based prospective study (NEDICES)

OBJECTIVE

the study aimed to assess the association between morale and mortality.

DESIGN

we used data from the Neurological Disorders in Central Spain (NEDICES), a population-based study.

SUBJECTS

2,516 older persons (mean age 75.7 years) participated in the study.

METHODS

Cox models were used to estimate risk of mortality. Morale was assessed using the Philadelphia Geriatric Center Morale Scale.

RESULTS

489 (21.8%) participants died over a median follow-up of 5.9 years (range 0.1-7.7 years), including 253 (21.8%) deaths among 1,163 participants with low morale scores, 168 (19.3%) among 870 participants with moderate scores and 68 (14.1%) among participants with high scores. In an unadjusted Cox model, relative risk (RR) of mortality in participants with low morale scores = 1.69 (P < 0.001) and RR in participants with moderate scores = 1.47 (P < 0.01) were compared to the reference group (participants with high scores). In a Cox model that adjusted for a variety of demographic factors and co-morbidities, RR of mortality in participants with low morale scores = 1.35 (P <0.05) and moderate scores = 1.16 (not significant) were compared to the reference group.

CONCLUSION

low morale may be an independent predictor of mortality in the elderly. By assessing morale, practitioners might be better positioned to identify patients with poorer prognoses.

Most of the Quality of Life in Essential Tremor Questionnaire (QUEST) psychometric properties resulted in satisfactory values

OBJECTIVE

This study sought to assess the psychometric attributes of the Quality of Life in Essential Tremor Questionnaire (QUEST) by undertaking an independent validation.

STUDY DESIGN AND SETTING

This was an observational, multicenter, cross-sectional study carried out in Neurology Departments of general hospitals. The following assessments were applied: Louis Rating Scale, Clinical Assessment of Tremor, Clinical Global Impression of Severity (CGI-ET), Hospital Anxiety and Depression Scale (HADS), EQ-5D, and QUEST (Spanish version).

RESULTS

One hundred and eighteen consecutive patients were included. According to the CGI-ET, most of patients had mild (42.4%) or moderate (43.2%) impact of tremor on performing daily activities. Fully computable QUEST data were 60.2%. The QUEST Summary Index (QUEST-SI) displayed marginal floor or ceiling effect. On the whole, QUEST internal consistency and reproducibility were satisfactory (Cronbach's alpha values: 0.73-0.86; QUEST-SI intraclass correlation coefficient: 0.77). Factor analysis identified eight factors (73.6% of the variance) that could be grouped into six, relatively coincident with the questionnaire's dimensions. The QUEST-SI correlated moderately with the EQ-5D index (r(S)=-0.40), HADS-Depression (r(S)=0.39), and CGI-ET (r(S)=0.39), and strongly with the QUEST scale for self-evaluation of tremor severity (r(S)=0.63). The standard error of measurement was 8.00.

CONCLUSION

Apart from a substantial problem of acceptability, most of the tested psychometric attributes of the QUEST resulted satisfactory.