Neurological Disorders In Central Spain Research Articles

Reported head trauma and odds of acute ischemic stroke or transient ischemic attack: A population-based study (NEDICES)

BackgroundSix previous observational studies have found a higher risk for stroke among traumatic head injury survivors. However, these studies have used record linkage systems, which could lead to underestimating stroke numbers. This study aims to reexamine the relationship between head trauma and the risk of ischemic stroke/transient ischemic attack (TIA) in an older population using data from the Neurological Disorders in Central Spain (NEDICES) study, a population-based study that includes rigorous clinical examinations for patients with suspected neurological diseases. MethodsWe asked participants if they had ever experienced head trauma that was severe enough to warrant a consult with a physician, leading, among others, to visiting the emergency room, hospitalization, or resulting in loss of consciousness. The history of head trauma was evaluated in 196 (5.7%) acute ischemic stroke/TIA cases and 3256 controls in the NEDICES study. ResultsAmong the final sample of 3452 participants, 354 (10.3%) subjects had a history of head trauma. Twenty-nine (14.8%) of 196 acute ischemic stroke/TIA cases vs. 325 (10.0%) of 3256 controls reported a history of head trauma (p = 0.039). In a regression analysis that adjusted for several variables (age in years, sex, educational level, ever smoker, ever drinker, diabetes mellitus, arterial hypertension, and heart disease), the odds ratio was 1.54 (95% CI = 1.02–2.35, p = 0.042). ConclusionsThe reported head injury was associated with a 54% higher probability of acute ischemic stroke/TIA. More research is needed to confirm these findings, especially using population-based longitudinal studies.

Association between cumulative smoking exposure and cognitive decline in non-demented older adults: NEDICES study

Whether cumulative smoking exposure is associated with cognitive decline among older adults remains unresolved. To address this question, we used data from the Neurological Disorders in Central Spain (NEDICES) cohort study, in which 2624 older adults were evaluated at two-time points separated by three years. A 37-item version of the Mini-Mental State Examination (MMSE-37) was administered at two visits to assess cognitive change. Regarding smoking exposure, we calculated an individual baseline score based on pack-years (i.e., packs of cigarettes smoked per day multiplied by years of smoking) in current and former smokers. Thus, smoking exposure was categorized into tertiles (low: < 19.0, medium: 19.0–47.0, and high: > 47.0). We used multivariable generalized estimating equation models to assess associations between pack-years and smoking status with 37-MMSE total score change from baseline to follow-up. The MMSE-37 total score had a decline of 1.05 points (confidence interval [CI] 95% 0.62 to 1.48) in the lower tertile of pack-years, 1.16 (CI 95% 0.70 to 1.62) in the middle tertile and 1.17 (CI 95% 0.70 to 1.65) in the higher tertile compared to never smokers, after adjusting for several demographic and clinical variables. The same occurred with smoking status, i.e., a decline of 1.33 (CI 95% 0.87 to 1.79) in current smokers and 1.01 (CI 95% 0.63 to 1.40) in former smokers. Our study provides evidence of the cumulative effect of smoking on cognition in older adults. Using a prospective population-based design, we demonstrated that cumulative smoking exposure was associated with cognitive decline in non-demented older adults. More population-based evidence is required to elucidate this association in older adults without dementia.

Physical activity and risk of Parkinson’s disease and parkinsonism in a prospective population-based study (NEDICES)

To investigate whether physical activity (PA) is a protective factor for the incidence of Parkinson’s disease (PD) and parkinsonism after three years of follow-up. All participants of this study were obtained from the Neurological Disorders in Central Spain (NEDICES), a prospective population-based cohort survey of older subjects (≥65 years) that comprised 5278 census-based participants at baseline (1994–1995). A modified version of Rosow-Breslau questionnaire was applied to categorize PA into active versus sedentary group. The final diagnosis of PD and parkinsonism was made by an expert neurologist. Cox regression models (CRM) adjusted for several covariates (sex, age, education, alcohol consumption, tobacco, stroke, hypertension and body mass index) were used to calculate the association between PA (active group vs. sedentary) and risk of PD and parkinsonism after three years. 22 incident PD and 25 incident parkinsonism cases were identified among 2943 participants with available PA information (57.1% female; mean age = 73.28 ± 6.24 years) after three years of follow-up. The CRM showed that the active group (vs. sedentary) showed a lower risk of parkinsonism (Hazard ratio (HR) = 0.18; 95% CI [0.07–0.51]; p = 0.0001). However, this effect was restricted to men (HR = 0.34; 95% CI [0.11–0.99], p < 0.05) for incident PD. PA may be a protective factor for incident parkinsonism, whereas this effect was only significant for men in the case of PD. The mechanisms implicated for brain maintenance in active individuals and the neurophysiological differences behind the role of sex on PD are discussed.

Comparison of mortality rate in older adults with and without functional awareness: the Neurological Disorders in Central Spain (NEDICES) population-based study

ObjectivesThe main aim of the study was to compare the rates of mortality in older adults with and without functional unawareness (FU). We also tested a possible interaction effect between levels of awareness and education, as a single cognitive reserve proxy, on mortality. Study designThe study design is a longitudinal population-based cohort study. MethodsThe Neurological Disorders in Central Spain is epidemiological study to detect main age-associated conditions in people aged 65 years and older. Participants were collected from updated population-based registers of residents in three areas of central Spain. Awareness of functional limitations was established in accordance with the discrepancy between two sources of information on functional impairments: reliable informants versus the participants themselves. Three mutually exclusive groups were formed, namely, Functional Limitation Complaints (FCs), FU, and Functional Awareness (FA). Cox's regression models, adjusted by different covariates, were used to calculate the risk of mortality for each group at 5-year follow-up (vs. reference group without limitations). ResultsOf 1818 selected individuals, 229 (12.5%) showed FA, 254 (13.9%) showed FC, and 96 (5%) were classified as FU. All these groups showed an increased risk of mortality at 5-year follow-up [adjusted hazard ratio (HR) for FC < FU < FA]. However, the association of FU with mortality remained significant only for highly educated individuals. ConclusionsFunctional impairment was associated with increased mortality rates, regardless of the presence of unawareness. This study extends the role of education in modulating the symptoms and prognosis of individuals at very mild or preclinical dementia stages.

Reliable change indices for the 37-item version of the MMSE in Spanish older adults

Objective The aim of this study was to establish reliable change and regression-based change score norms on the 37-item version of MMSE in older Spanish adults at the three-year follow-up. Method All subjects of this research were selected from the Neurological Disorders in Central Spain (NEDICES), a prospective population-based cohort study of older adults (65 years and over). Of the 4208 individuals free from neurological disorders in this cohort, 2073 participants completed the MMSE-37 at baseline and at the three-year follow-up. Reliable Change Indices were computed for the 80, 90% and 95 confidence intervals (CIs). Multiple regression analyses were used to derive equations for predicting MMSE-37 post-test scores taking into account baseline scores, time to follow-up and sociodemographic factors. Results The MMSE-37 obtained a marginal test-retest reliability (.70). The results showed significant effects of education, age, and sex on the MMSE-37 change scores. After correcting for regression to the mean, at least a 6-point change on MMSE-37 (three-years follow-up) is required to be classified as reliable (90% CI). Conclusions These findings demonstrate that the MMSE-37 is a reliable test-retest measure whose change scores are significantly influenced by sociodemographic factors. Importantly, small changes on this measure require a cautious interpretation.

Non-steroidal anti-inflammatory drugs use in older adults decreases risk of Alzheimer's disease mortality.

Alzheimer disease (AD) mortality risk in a large cohort of subjects treated or not with non-steroidal anti-inflammatory drugs (NSAIDs) is unknown. Our objective was to determine whether NSAIDs use is associated with decreased risk of AD mortality. In this prospective, population-based study (Neurological Disorders in Central Spain [NEDICES]) of 5,072 people without AD (aged 65 years and older), sociodemographic, comorbidity factors, and current medications were recorded at baseline. Community-dwelling older adults were followed for a median of 12.7 years, after which the death certificates of deceased participants were examined. 2,672 (52.7%) of 5,072 participants died, including 504 (18.9%) NSAIDs users and 2,168 (81.1%) non-users. Of the 2,672 deceased participants, 113 (4.2%) had AD as a cause of death (8 [1.6%] among NSAIDs users and 105 [4.8%] among non-users, chi-square = 10.70, p = 0.001). In an unadjusted Cox model, risk of AD mortality was decreased in NSAIDs users (hazard ratio [HR] for AD mortality = 0.35, 95% confidence interval [CI] 0.17–0.72, p = 0.004) when compared to non-users. After adjusting for numerous demographic factors and co-morbidities, the HR for AD mortality in NSAIDs users was 0.29, 95% CI 0.12–0.73, p = 0.009. Stratified analyses showed a significantly decreased risk of AD mortality with aspirin, whereas non-aspirin NSAIDs only showed a statistical trend toward significance in the adjusted Cox regression models. NSAIDs use was associated with 71% decreased risk of AD mortality in older adults. Our results support the hypothesis that NSAIDs use is a protective factor of developing AD.

Neurological Disorders in Central Spain, Second Survey: Feasibility Pilot Observational Study.

BackgroundThe Neurological Disorders in Central Spain, second survey (NEDICES-2) is a population-based, closed-cohort study that will include over 8000 subjects aged ≥55 years. It will also include a biobank.ObjectiveThe objective of this study was to evaluate all major aspects of the NEDICES-2 (methods, database, screening instruments, and questionnaires, as well as interexpert rating of the neurological diagnoses) in each one of the planned areas (all of them in central Spain) and to test the possibility of obtaining biological samples from each participant.MethodsA selection of patients and participants of the planned NEDICES-2 underwent face-to-face interviews including a comprehensive questionnaire on demographics, current medications, medical conditions, and lifestyle habits. Biological samples (blood, saliva, urine, and hair) were also obtained. Furthermore, every participant was examined by a neurologist.ResultsIn this pilot study, 567 study participants were enrolled (196 from hospitals and 371 from primary care physician lists). Of these 567, 310 completed all study procedures (questionnaires and the neurological evaluation). The study was time-consuming for several primary care physicians. Hence, a few primary care physicians from some areas refused to participate, which led to a reconfiguration of study areas. In addition, the central biobank needed to be supplemented by the biobanks of local Spanish National Health System hospitals.ConclusionsPopulation-based epidemiological surveys, such as the NEDICES-2, require a pilot study to evaluate the feasibility of all aspects of a future field study (population selection, methods and instruments to be used, neurological diagnosis agreement, and data collection).

Characterizing functional alterations in instrumental activities of daily living using latent class analysis: a population-based study (NEDICES)

Background and Objectives: The existence of different patterns of functional impairment in older adults has scarcely been addressed. This research investigates major patterns of functional impairment based on Pfeffer's Functional Activity Questionnaire (FAQ).Research Design and Methods: The participants come from NEDICES (Neurological Disorders in Central Spain), a prospective population-based cohort study. A total of 3837 individuals without dementia who completed the Spanish version of the FAQ was selected. Latent Class Analysis (LCA) was carried out to examine potential cluster subgroups based on FAQ responses.Results: The FAQ showed good internal consistency (Cronbach’s alpha: 0.86) and moderate correlation (r = −.40) with cognitive performance on the Mini-Mental State Examination (MMSE-37). The response patterns revealed the presence of three latent classes: absence of functional alteration (Class 1), established functional alteration (Class 2), and minimal functional alteration (Class 3). Moreover, the probability of resolving Items 2 (‘shopping alone for…’), 3 (‘heating water…’), 4 (‘preparing a balanced meal’), and 9 (‘travelling out of neighbourhood…’) was close to 0% for Class 2 membership, while those with the lowest probability of resolution for Class 3 were Items 2 and 9. Items 3 and 4 were the best to discriminate between different grades of functional alterations (Class 2 vs. Class 3).Discussion and Implications: Our findings indicate that the combination of overall FAQ score and item response pattern may help to classify individuals with different subtypes of functional impairment. The Spanish version of the FAQ is a useful tool for detection of functional impairment in older adults.

Is Educational Attainment Associated with Increased Risk of Mortality in People with Dementia? A Population-based Study.

The association between higher education and increased mortality in Alzheimer's disease (AD) is controversial. Further it is unknown whether education predicts survival in all dementia subtypes. We assessed mortality rates and death causes of persons with dementia compared to participants without dementia. Participants derive from the Neurological Disorders in Central Spain, a prospective population- based cohort study of older adults. We compared 269 persons with dementia to 2944 participants without dementia. We carried out Cox regression models to predict the risk of mortality dependent on the educational attainment adjusting for covariates. Reasons of death were obtained from the National Population Register. During a median follow-up of 5.4 years, 400 individuals died (171 with dementia, 229 without dementia). Among the participants with dementia, those with higher educational attainment had an increased risk of death than those with lower education; the adjusted hazard ratio (HRa) was 1.40 (95% confidence interval [CI], 1.01 to 1.94). When the analysis was restricted to patients with AD the HRa increased to 1.51 (95% CI = 1.01-2.24). By contrast, educational attainment was not associated with increased mortality among participants without dementia (HRa = 0.92, 95% CI = 0.71-1.20, p = 0.55), whereas education did not influence mortality in QD. Our findings suggest that high educational attainment is associated with increased mortality risk in people with dementia. This observation implies that neuropathology is more advanced in patients with higher education at any level of clinical severity, leading these individuals to an earlier death after diagnosis.

Physical activity and long-term mortality risk in older adults: A prospective population based study (NEDICES).

To analyze whether Physical activity (PA) reduces mortality risk at thirteen years' follow-up in a population-based cohort of Spanish older adults. The NEDICES (Neurological Disorders in Central Spain) is a prospective population-based survey of older adults (age ≥ 65 years) that comprised 5278 participants at baseline. A modified version of the Rosow-Breslau questionnaire was applied to categorize the PA (sedentary, light, moderate and high) and dates of death were collected from the Official Spanish Death Registry. Cox regression models adjusted for different covariates (age, sex, marital status, smoking, previous stroke, Parkinson disease, incident dementia, body mass index, comorbidity indexes and functional assessment) were used to evaluate the hazard of death at thirteen years' interval according to different levels of PA. 1710 deaths (52.9% men vs. 47.1% women) were identified among 3633 individuals at thirteen years' follow-up. Hazard ratios (HRs) of the light, moderate, and high PA groups (vs. sedentary group) were 0.64 (95% confidence interval (CI) [0.56, 0.72], p < 0.001), 0.61 (95% CI [0.53, 0.70], p < 0.001) and 0.48 (95% CI [0.41, 0.55], p < 0.001), respectively. Significant dose effects were observed between light versus the sedentary group and intense versus the moderate group. PA prevents long-term mortality in older Spanish adults, with the highest intensity levels being those related to the lowest risk of mortality. These findings indicate that health policies for old age care should include PA as one of the main targets.

Semantic Verbal Fluency: Normative Data in Older Spanish Adults From NEDICES Population-Based Cohort.

We aimed to provide the normative data stratified by age, sex and educational attainment for two semantic categories (animal and fruits) in older Spanish adults. A representative sample of 2,744 non-demented older individuals with different socioeconomic background was selected from the Neurological Disorders in Central Spain (NEDICES), a population-based study. Normative data are presented in percentile ranks and divided into four age-tables with different midpoints, using the overlapping interval procedure. Correlation analyses showed that age, education and sex influence significantly the scores in both semantic tasks. Normative data presented here covered two urban (Margaritas & Lista) and one rural areas (Arévalo). These norms may provide useful data for screening cognitive impairment more accurately in Spanish older adults.

Impact of literacy and years of education on the diagnosis of dementia: A population-based study

ABSTRACTBackground. The effect of different educational indices on clinical diagnosis of dementia requires more investigation. Objective. We compared the differential influence of two educational indices (EIs): years of schooling and level of education (i.e., null/low literacy, can read and write, primary school, and secondary school) on global cognition, functional performance, and the probability of having a dementia diagnosis. Method. A total of 3,816 participants were selected from the population-based study of older adults “Neurological Disorders in Central Spain” (NEDICES). The 37-item version of the Mini-Mental State Examination (MMSE–37) and the Pfeffer’s questionnaire were applied to assess cognitive and functional performance, respectively. The diagnosis of dementia was performed by expert neurologists according to Diagnostic and Statistical Manual of Mental Disorders–Fourth Edition (DSM–IV) criteria. Logistic regression models adjusted for potential confounders were carried out to test the association between the two EIs and dementia diagnosis. Results. Both EIs were significantly associated with cognitive and functional scores, but individuals with null/low literacy performed significantly worse on MMSE–37 than literates when these groups were compared in terms of years of schooling. The two EIs were also related to an increased probability of dementia diagnosis in logistic models, but the association’s strength was stronger for level of education than for years of schooling. Conclusion. Literacy predicted cognitive performance over and above the years of schooling. Lower education increases the probability of having a dementia diagnosis but the impact of different EIs is not uniform.

Education and risk of incident dementia during the premotor and motor phases of essential tremor (NEDICES).

Individuals with late-onset essential tremor (ET) (e.g., older adults) seem to have an increased prevalence of mild cognitive impairment and dementia, and a higher risk of incident dementia. It is well-known that education has a protective role against dementia in individuals without a pre-existing neurologic disorder, but evidence regarding the maintenance of this effect during the premotor and motor phases of ET is unknown. Our aim was to determine the influence of education on the risk of dementia in a population-based cohort of ET patients and controls. In a prospective study (Neurological Disorders in Central Spain), participants ≥65 years old were evaluated twice: at baseline (1994–1995) and at follow-up (1997–1998). There were 3 groups: premotor (i.e., participants first diagnosed with incident ET at follow-up), prevalent ET (i.e., participants diagnosed with ET at baseline and at follow-up), and controls. Participants were stratified into lower education (≤primary studies) versus higher education (≥secondary studies) categories. Dementia risk was estimated using Cox proportional-hazards models (higher education control group = reference category). Among the participants, 3878 had a mean duration of follow-up of 3.2 years. Eight (16.7%) of 48 lower education premotor ET patients developed incident dementia versus 1 (3.3%) of 30 higher education premotor ET patients, 9 (7.1%) of 126 lower education prevalent ET patients, 7 (8.8%) of 80 higher education prevalent ET patients, and 92 (4.9%) of 1892 lower education controls (P < 0.001). In comparison to the higher education controls, the adjusted hazard ratios for incident dementia were 5.84 (lower education premotor ET, P < 0.001); 1.36 (higher education premotor ET, P = 0.76); 2.13 (lower education prevalent ET, P = 0.04); 2.79 (higher education prevalent ET, P = 0.01); and 1.66 (lower education controls, P = 0.01). Our results suggest that a higher educational attainment may ameliorate the risk of incident dementia during the premotor phase of ET, but not in the motor phase.

Inter-Rater Agreement in the Clinical Diagnosis of Cognitive Status: Data from the Neurological Disorders in Central Spain 2 Pilot Study

Background: To assess the diagnostic agreement of cognitive status (dementia, mild cognitive impairment (MCI), normal cognition) among neurologists in the field of neurological disorders in Central Spain 2 study. Methods: Full medical histories of 30 individuals were provided to 27 neurologists: 9 seniors, 10 juniors and 8 residents. For each case, we were asked to assign a diagnosis of dementia, MCI or normal cognition using the National Institute on Aging-Alzheimer's Association workgroup (NIA-AA) core clinical criteria for all-cause dementia, Winblad et al. criteria for MCI, and analyze intensity and etiology if dementia was diagnosed. Inter-rater agreement was assessed both with percent concordance and non-weighted κ statistics. Results: Overall inter-rater agreement on cognitive status was κ = 0.76 (95% CI 0.65-0.86), being slightly higher among junior neurologists (κ = 0.85, 95% CI 0.73-0.95) than among seniors (κ = 0.71, 95% CI 0.59-0.83) and residents (κ = 0.69, 95% CI 0.54-0.81) but without statistical significance among groups. Dementia severity showed an overall κ of 0.34, 0.44 and 0.64 for mild, moderate and severe dementia respectively. Conclusions: Substantial agreement was demonstrated for the diagnosis of cognitive status (dementia, MCI and normal cognition) among neurologists of different levels of experience in a population-based epidemiological study using NIA-AA and Winblad et al. criteria. The agreement rate was lower in the diagnosis of dementia severity.

Prognostic Significance of Mild Cognitive Impairment Subtypes for Dementia and Mortality: Data from the NEDICES Cohort.

The predictive value of diverse subtypes of mild cognitive impairment (MCI) for dementia and death is highly variable. To compare the predictive value of several MCI subtypes in progression to dementia and/or mortality in the NEDICES (Neurological Disorders in Central Spain) elderly cohort. Retrospect algorithmic MCI subgroups were established in a non-dementia baseline NEDICES cohort using Spanish adaptations of the original Mini-Mental State Examination (MMSE-37) and Pfeffer's Functional Activities Questionnaire (Pfeffer-11). The presence of MCI was defined according two cognitive criteria: using two cut-offs points on the total MMSE-37 score. Five cognitive domains were used to establish the MCI subtypes. Functional capacity (Pfeffer-11) was preserved or minimally impaired in all MCI participants. The incident dementia diagnoses were established by specialists and the mortality data obtained from Spanish official registries. 3,411 participants without dementia were assessed in 1994-5. The baseline prevalence of MCI varied according to the MCI definition (4.3%-31.8%). The follow-up was a mean of 3.2 years (1997-8). The dementia incidence varied between 14.9 and 71.8 per 1,000/person-years. The dementia conversion rate was increased in almost all MCI subgroups (p > 0.01), and mortality rate was raised only in four MCI subtypes. The amnestic-multi-domain MCI (aMd-MCI) had the best dementia predictive accuracy (highest positive likelihood ratio and highest clinical utility when negative). Those with aMd-MCI were at greatest risk of progression to dementia, as in other surveys and might be explored with increased attention in MCI research and in dementia preventive trials.

Physical Activity as Protective Factor against Dementia: A Prospective Population-Based Study (NEDICES).

The aim of this study was to analyze whether physical activity (PA) is a protective factor for the incidence of dementia after 3 years of follow-up. The Neurological Disorders in Central Spain (NEDICES) is a prospective population-based survey of older adults (age 65 years and older) that comprised 5278 census-based participants at baseline (1994-1995). A broad questionnaire was used to assess participants' sociodemographic characteristics, health status, and lifestyle. Subsequently, a modified version of Rosow-Breslau questionnaire was applied to classify individuals' baseline PA into groups (i.e., sedentary, light, moderate, and high). Cox regression models adjusted for several covariates (age, sex, education, previous stroke, alcohol consumption, hypertension, health related variables) were carried out to estimate the association between the PA groups and risk of dementia at the 3-year follow-up (1997-1998). A total of 134 incident dementia cases were identified among 3105 individuals (56.6% female; mean age=73.15 ± 6.26) after 3 years. Hazard ratios (HRs) of the light, moderate, and high PA groups (vs. sedentary group) were 0.40 (95% confidence interval {CI} [0.26, 0.62]; p<.001), 0.32 (95% CI [0.20, 0.54]; p<.001) and 0.23 (95% CI [0.13, 0.40]; p<.001), respectively. Even after controlling for covariates and the exclusion of doubtful dementia cases, HRs remained significant. However, a supplementary analysis showed that the dose-effect hypothesis did not reach statistical significance. PA is a protective factor of incident dementia in this population-based cohort.

Accuracy of a Brief Neuropsychological Battery for the Diagnosis of Dementia and Mild Cognitive Impairment: An Analysis of the NEDICES Cohort

Early separation of mild cognitive impairment (MCI) from normal aging and mild cases of dementia remains a challenge, especially in the general population. We aimed to analyze the diagnostic accuracy of a brief neuropsychological battery (BNB) in dementia and MCI cases from the Neurological Disorders in Central Spain (NEDICES) population-based cohort study. We screened 3,891 participants into dementia and non-dementia groups using a two-phase procedure: screening (MMSE-37 and Pfeffer-11) and clinical diagnosis by specialists (DSM-IV criteria). We selected subsequently a subsample of dementia (n = 98), MCI (n = 71), and cognitively healthy (n = 123) participants matched in socio-demographic characteristics. The clinical validity of each test of the BNB was determined by the area under the ROC curve. We determined the best combination of tests to classify individuals into the diagnostic groups by logistic regression analyses. The results indicated that dementia and MCI groups could be best discriminated from the healthy control group on the basis of their scores on the semantic verbal fluency and delayed recall subtests of the BNB. As for discriminating the MCI group from the dementia group, immediate recall tasks (stories and pictures) yielded the highest level of accuracy. Probably the most interesting finding is that the verbal fluency task consistently allowed discrimination among the diagnostic groups. Overall, subtests of the BNB are more accurate in differentiating dementia patients than MCI patients from healthy controls. In this population-based sample, a more fine-grained discrimination that includes MCI patients should follow a systematic subtest-wise analysis and decision.

Serious head trauma preceding essential tremor: A population-based study (NEDICES)

BackgroundAn association between head trauma and essential tremor (ET) has not been formally assessed. Our purpose was to assess the association between serious head trauma and ET. MethodsHistory of head trauma was assessed in 274 ET cases and 3201 controls in the Neurological Disorders in Central Spain (NEDICES) study, a population-based study in central Spain. Head trauma was defined as serious only if the subject reported that the trauma resulted in loss of consciousness, hospitalization, or a visit to the emergency department. ResultsThirty-two (11.7%) of 274 ET cases vs. 260 (8.1%) of 3201 controls reported a history of serious head trauma (p=0.04). In an adjusted logistic regression analysis, participants who reported serious head trauma were 52% more likely to have ET (odds ratio [OR] 1.52; 95% confidence interval [CI] 1.02–2.27, p=0.04). The odds of ET increased with increasing age of head trauma: adjusted ORs=1.23 (95% CI 0.43–3.46, p = 0.70) for serious head trauma that occurred before age 18years, adjusted OR=1.49 (95% CI 0.62–3.55, p = 0.37) for serious head trauma between ages 18 to 39years, and adjusted OR=1.61 (95% CI 1.00–2.57, p = 0.04) for serious head trauma at age 40years or older. ConclusionsOur study suggests that serious head trauma, especially when it occurs after 40years, is associated with increased odds of ET. Additional studies are needed to reproduce this novel finding.

Effects of education and word reading on cognitive scores in a community-based sample of Spanish elders with diverse socioeconomic status

Introduction. The influence of education and oral word-reading ability on cognitive performance was examined in a sample of 1510 nondemented elders differing in socioeconomic status (SES) from three Spanish communities. Method. All individuals were enrolled in the Neurological Disorders in Central Spain, a population-based epidemiological study in central Spain. They completed a detailed demographic survey and a short standardized neuropsychological battery assessing psychomotor speed, attention, language, and memory. The Word Accentuation Test (WAT) was used as measure of oral reading ability. The influence of education and oral reading on cognitive performance was determined by multiple linear regression models, first controlling for demographics (age and sex), and subsequently for the WAT score and education. The contribution of socioeconomic conditions was addressed by stratifying the sample into groups of high and low SES. Results. The WAT showed a significant independent effect on cognitive scores, generally greater than that predicted by demographics. The higher predictive power of oral word reading on cognitive scores compared to education was consistent across the three communities. Although the variance explained by WAT was very similar in areas with diverse SES (low vs. high), WAT scores accounted for slightly more variance in naming and memory tasks in low SES areas. In contrast, the variance explained by WAT was higher for verbal fluency and the Trail-Making Test in areas with high SES. Conclusion. Oral word-reading ability predicts cognitive performance better than years of education across individuals with different SES. The influence of WAT may be modulated by SES and cognitive task properties.

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.