Understanding the relationship between freezing of gait and other progressive supranuclear palsy features

IntroductionFreezing of gait (FoG) leads to falls and reduces quality of life, but little is known about FoG in progressive supranuclear palsy (PSP). This study aim was to identify the clinical parameters associated with FoG in PSP patients.Methods349 patients meeting the National Institute for Neurological Disorders and Society for PSP (NINDS-SPSP) clinical diagnostic criteria were divided into two groups: PSP with FoG (n = 159) and PSP without FoG (n = 190). To determine if FoG in PSP associates with demographics, motor performance, visual difficulties, and executive function, we used the Frontal Assessment Battery (FAB), Mattis Dementia Rating Scale (DRS), Unified Parkinson's Disease Rating Scale (UPDRS), PSP Rating Scale (PSPRS), Modified Hoehn & Yahr staging, and Schwab and England Activities Daily Living (S&EADL) scale. UPDRS was used to identify FoG. Individual items of each clinical assessment with p-value < 0.05 in the univariate logistic regression analyses were included in the backward stepwise multivariate regression analysis.ResultsBoth groups were similar in demographics. 45.6% of patients had FoG, which was present at onset and increased with disease duration. There were no between-group significant associations between FoG and visual disturbances, executive function and overall cognition, but on univariate analyses, FoG was significantly associated with bradykinesia, rigidity, gait, and posture. In the multivariate model FoG was associated with disease duration and speech.ConclusionsOur findings indicate that disease duration and speech have the most significant association with FoG. These findings may suggest that FoG and speech difficulties in PSP share a similar pathophysiology.     

Falls in outpatients with Parkinson's disease

Falls are one of the most serious complications of gait disturbances in patients with Parkinson's disease (PD). Among previous reports, the percentage of patients with PD who fall varies between 38% to 68%. We sought to determine the frequency of falls and the factors associated with falls in a group of patients with idiopathic PD who attended an outpatient, tertiary movement disorders clinic. 350 ambulatory, non–demented patients (230 males) were studied. Mean age was 69.7 ± 10.6 years (range: 43–97 yrs) and mean duration of PD symptoms was 8.6 ± 6.2 years (range: 1–33 yrs). Assessments included characterization of demographics, disease duration, disease severity as measured by the Hoehn and Yahr Scale (H&Y), co–morbidities, the presence of depressive symptoms, the presence of urinary incontinence, use of anti–parkinsonian medications, and two performance–based tests of balance and gait (tandem standing and Timed Up & Go). Fall history was determined during three time periods: previous week, previous month, and previous year. Univariate and multivariate logistic regression models were applied to evaluate the relationship between the above–mentioned factors and falls. 46% of the subjects reported at least one fall in the previous year and 33% reported 2 or more falls and were classified as Fallers. Fallers had significantly more prolonged and advanced PD compared with Non–fallers (p = 0.001 and p < 0.001, respectively). Urinary incontinence was the factor most closely associated with falls (crude and adjusted OR were 1.95 and 5.89, respectively). Other factors significantly associated with fall status included increased Timed Up & Go times and increased PD duration. These findings confirm that falls are a common problem among patients with advanced PD and suggest easily measurable features that may be used to prospectively identify those PD patients with the greatest risk of falls.     

Motor dual-tasking deficits predict falls in Parkinson's disease: A prospective study

IntroductionFalls severely affect lives of Parkinson's disease (PD) patients. Cognitive impairment including dual-tasking deficits contribute to fall risk in PD. However, types of dual-tasking deficits preceding falls in PD are still unclear.MethodsWalking velocities during box-checking and subtracting serial 7s were assessed twice a year in 40 PD patients over 2.8 ± 1.0 years. Fourteen patients reported a fall within this period (4 excluded fallers already reported falls at baseline). Their dual-task costs (DTC; mean ± standard deviation) 4.2 ± 2.2 months before the first fall were compared with 22 patients never reporting falls. ROC analyses and logistic regressions accounting for DTC, UPDRS-III and disease duration were used for faller classification and prediction.ResultsOnly walking/box-checking predicted fallers. Fallers showed higher DTC for walking while box-checking, p = 0.029, but not for box-checking while walking, p = 0.178 (combined motor DTC, p = 0.022), than non-fallers. Combined motor DTC classified fallers and non-fallers (area under curve: 0.75; 95% confidence interval, CI: 0.60–0.91) with 71.4% sensitivity (95%CI: 41.9%–91.6%) and 77.3% specificity (54.6%–92.2%), and significantly predicted future fallers (p = 0.023). Here, 20.4%-points higher combined motor DTC (i.e. the mean difference between fallers and non-fallers) was associated with a 2.6 (1.1–6.0) times higher odds to be a future faller.ConclusionMotor dual-tasking is a potentially valuable predictor of falls in PD, suggesting that avoiding dual task situations as well as specific motor dual-task training might help to prevent falls in PD. These findings and their therapeutic relevance need to be further validated in PD patients without fall history, in early PD stages, and with various motor-motor dual-task challenges.     

Fall frequency and risk assessment in early Parkinson's disease

BackgroundWe sought to define the frequency of falls in early PD and assess potential risk factors for falls in this population.MethodsWe analyzed the data from two randomized, placebo controlled trials (NET-PD FS1 and FS-TOO) of 413 individuals with early PD over 18 months of follow-up in FS1 and 12 months in FS-TOO. Falls were defined as any report of falls on the UPDRS or the adverse event log. We assessed the frequency of falls overall and by age. The relationship between prespecified fall risk markers and the probability of falling was assessed using logistic and multiple logistic regression. A hurdle Poisson model was used to jointly model the probability of remaining fall-free and the number of falls.ResultsDuring the follow-up period, 23% of participants fell, and 11% were habitual fallers. In a multiple logistic regression model, age, baseline UPDRS Falling score, and baseline PDQ-39 scores were associated with subsequent fall risk (p < 0.001). Similarly, in a hurdle Poisson regression model, age, baseline UPDRS falling item, and baseline PDQ-39 were all significantly related to the probability of falling, but only UPDRS falling >0 was associated with the number of falls.ConclusionFalls are frequent and are associated with impaired quality of life, even in early PD. Current standard rating scales do not sufficiently explain future fall risk in the absence of a prior fall history. New assessment methods for falls and postural instability are required to better evaluate this important problem in clinical trials and clinical practice.     

Association of PSP phenotypes with survival: A brain-bank study

IntroductionThe MDS-PSP criteria expand the phenotypic spectrum of PSP by adding to Richardson's syndrome (PSP-RS) other presentations such as PSP-parkinsonism (PSP–P), PSP-pure-gait-freezing (PSP-PGF), PSP-speech-language (PSP-SL), PSP-frontal (PSP–F), PSP-postural-instability (PSP-PI) and PSP-corticobasal-syndrome (PSP-CBS). Evidence about the prognostic differences between PSP phenotypes is scarce and focused on PSP-RS vs. non-PSP-RS. Using a brain-bank cohort we assessed PSP survival not only in PSP-RS vs. non-PSP-RS, but also in PSP-RS + cortical vs. subcortical phenotypes. Besides, we assessed sensitivity and specificity of the MDS-PSP criteria in of PSP and other degenerative parkinsonisms.MethodsWe retrospectively applied the MDS-PSP diagnostic criteria to 32 definite PSP cases and 30 cases with other degenerative parkinsonian syndromes (Parkinson's disease [PD; n = 11], multiple system atrophy [MSA; n = 11], corticobasal degeneration [CBD; n = 8]). We conducted survival statistics in neuropathologically confirmed PSP cases considering PSP-RS vs. non-PSP-RS and PSP-RS + PSP-cortical (PSP–F + PSP-SL + PSP-CBS) vs. PSP-subcortical (PSP–P + PSP-PGF) phenotypes. We also adjusted survival analyses for PSP tau scores.ResultsDiagnostic sensitivity was 100% and specificity ranged from 47% to 87% when excluding cases that met the “suggestive of PSP” definition early in their disease course but with other clinical features better matching with a non-PSP pathological diagnosis. Survival was significantly shorter in PSP-RS vs. non-PSP-RS cases, but it was more markedly shorter in PSP-RS + PSP-cortical vs. PSP-subcortical, independently of PSP tau scores, which were not associated with survival.ConclusionsPSP-subcortical phenotypes appear to have longer survival than PSP-RS and cortical phenotypes. This might be of prognostic relevance when informing patients upon clinical diagnosis.     

Effects of sleep duration and weekend catch-up sleep on falling injury in adolescents: a population-based study

ObjectiveThis population-based study aimed to determine the effects of sleep deprivation and compensatory weekend catch-up sleep on the risk of falls in adolescents.MethodsData from the 2013 Korean Youth Risk Behavior Web-based Survey on 57,225 adolescents were investigated. Demographic, socioeconomic, sleep-related, health-related behavioral, and psychological variables were compared between fallers (n = 7346) and non-fallers (n = 49,879). Multivariate logistic regression analysis using a hierarchical model was carried out to identify sleep-related factors (eg, sleep duration, longer weekend catch-up sleep) independently contributing to the risk of falls.ResultsCompared to non-fallers, fallers were associated with a shorter sleep duration (p = 0.001) and later bedtimes on weekdays and weekends (p < 0.001). An average sleep duration of ≤ 5 h (odds ratio [OR] 1.23, 95% confidence interval [CI] 1.12–1.34) and of 6 h (OR 1.12, CI 1.03–1.21) were associated with an increased risk of falls. By contrast, an average sleep duration of ≥ 9 h (OR 0.90, CI: 0.82–0.99) and longer weekend catch-up sleep (OR 0.94, CI: 0.89–0.99) were associated with a decreased risk of falls.ConclusionOur results corroborate previous suggestions that short sleep duration is a major risk factor for falls among adolescents. Moreover, our study provided a novel finding that longer sleep duration and longer weekend catch-up sleep may have a protective effect against falls. Our findings have important public health implications that modifying school schedules to increase sleep duration could reduce unintentional falls and injuries in school-aged adolescents.     

Cerebral peduncle angle: Unreliable in differentiating progressive supranuclear palsy from other neurodegenerative diseases

IntroductionThe significant symptom overlap between progressive supranuclear palsy (PSP) and other parkinsonian neurodegenerative diseases frequently results in misdiagnosis. However, neuroimaging can be used to quantify disease-related morphological changes and specific markers. The cerebral peduncle angle (CPA) has been shown to differentiate clinically diagnosed PSP from other parkinsonian diseases but this result has yet to be confirmed in autopsy-proven disease.MethodsMagnetic resonance imaging (MRI) scans were obtained for 168 patients representing 69 medical facilities. Following randomization, the images were divided into two groups (Type 1 and Type 2) based upon midbrain morphological differences. Two readers were blinded and independently measured the CPA of 146 patients with autopsy-proven progressive supranuclear palsy (PSP; n = 54), corticobasal degeneration (n = 16), multiple system atrophy (MSA; n = 11) and Lewy body disease (n = 65).ResultsApplying two separate measurement techniques revealed no statistically significant differences in CPA measurements among any study groups regardless of classification measurement approach. The interobserver agreement showed significant differences in measurements using the Type 2 approach.ConclusionMeasuring the CPA on MRI is not a reliable way of differentiating among patients with PSP, corticobasal degeneration, MSA, or Lewy body disease.     

Clinical and dual‐tasking aspects in frequent and infrequent fallers with progressive supranuclear palsy

Progressive supranuclear palsy (PSP) is a rare neurodegenerative disease with no sufficient therapeutic options to date. Falls are the most devastating feature. The causes of these falls are not well understood. To test the impact of PSP‐associated motor and cognitive features on falls, 26 PSP patients were prospectively recruited and divided into frequent fallers (> one fall/month, 18 patients) and infrequent fallers (≤ one fall/month, 8 patients). Further parameters were assessed by clinical investigation and biomechanical gait and balance analysis with and without dual‐task paradigms. Physical activity was measured through an ambulatory device. Frequent fallers scored higher on the total PSP rating scale and the subscales “history,” “mental,” “bulbar,” “supranuclear ocular motor,” and “gait/midline exam” but not on disease duration, the subscale “limb exam,” the UPDRS motor score and the sway analysis. Frequent fallers also showed an increased probability of an altered walking pattern with shortened step lengths and increased cadence under a dual‐task situation. It is concluded that the occurrence of falls in PSP seems strongly associated with the deterioration of bulbar function, but not relevantly with typical parkinsonian features like rigidity and bradykinesia. The decreased ability to deal with distraction of attention under a dual‐task situation points to a relevant impact of cortical and subcortical dysfunction on the frequency of falls. © 2010 Movement Disorder Society     

Predicting disease progression in progressive supranuclear palsy in multicenter clinical trials

IntroductionClinical and MRI measurements can track disease progression in PSP, but many have not been extensively evaluated in multicenter clinical trials. We identified optimal measures to capture clinical decline and predict disease progression in multicenter PSP trials.MethodsLongitudinal clinical rating scales, neuropsychological test scores, and volumetric MRI data from an international, phase 2/3 clinical trial of davunetide for PSP (intent to treat population, n = 303) were used to identify measurements with largest effect size, strongest correlation with clinical change, and best ability to predict dropout or clinical decline over one year as measured by PSP Rating Scale (PSPRS).ResultsBaseline cognition as measured by Repeatable Battery for Assessing Neuropsychological Status (RBANS) was associated with attrition, but had only a small effect. PSPRS and Clinical Global Impression (CGI) had the largest effect size for measuring change. Annual change in CGI, RBANS, color trails, and MRI midbrain and ventricular volumes were most strongly correlated with annual PSPRS and had the largest effect sizes for detecting annual change. At baseline, shorter disease duration, more severe depression, and lower performance on RBANS and executive function tests were associated with faster worsening of the PSPRS in completers. With dropouts included, SEADL, RBANS, and executive function tests had significant effect on PSPRS trajectory of change.ConclusionBaseline cognitive status and mood influence the rate of disease progression in PSP. Multiple clinical, neuropsychological, and volumetric MRI measurements are sensitive to change over one year in PSP and appropriate for use in multicenter clinical trials.     

Factors associated with fall-related fractures in Parkinson's disease

PurposeFall-related fracture is one of the most disabling features of idiopathic Parkinson's disease (PD). A better understanding of the associated factors is needed to predict PD patients who will require treatment.MethodsThis prospective study enrolled 100 adult idiopathic PD patients. Stepwise logistic regressions were used to evaluate the relationships between clinical factors and fall-related fracture.ResultsFalls occurred in 56 PD patients, including 32 with fall-related fractures. The rate of falls in the study period was 2.2 ± 1.4 per 18 months. The percentage of osteoporosis was 34% (19/56) and 11% in PD patients with and without falls, respectively. Risk factors associated with fall-related fracture were sex, underlying knee osteoarthritis, mean Unified Parkinson's Disease Rating Scale score, mean Morse fall scale, mean Hoehn and Yahr stage, and exercise habit. By stepwise logistic regression, sex and mean Morse fall scale were independently associated with fall-related fracture. Females had an odds ratio of 3.8 compared to males and the cut-off value of the Morse fall scale for predicting fall-related fracture was 72.5 (sensitivity 72% and specificity 70%).DiscussionHigher mean Morse fall scales (>72.5) and female sex are associated with higher risk of fall-related fractures. Preventing falls in the high-risk PD group is an important safety issue and highly relevant for their quality of life.     

Bilateral early activity in the hip flexors associated with falls in stroke survivors: Preliminary evidence from laboratory-induced falls

Objective

Falls are the most common and expensive medical complication following stroke. Hypermetric reflexes have been suggested to impact post-stroke balance but no study has evaluated reflex amplitudes under real conditions of falls in this population. Our objective was to quantify the early reflexive responses during falls induced in the laboratory.

Clinical correlates of longitudinal brain atrophy in progressive supranuclear palsy

IntroductionThere are no effective treatments for progressive supranuclear palsy (PSP). Volumetric MRI (vMRI) may be a useful surrogate outcome measure in PSP clinical trials. The goal of the study was to evaluate the potential of vMRI to correlate with clinical outcomes from an international clinical trial population.MethodsPSP patients (n = 198) from the AL-108-231 trial who had high quality vMRI and Progressive Supranuclear Palsy Rating Scale (PSPRS), Repeatable Battery for the Assessment of Neuropsychological Status (RBANS), Schwab and England Activities of Daily Living (SEADL), Color Trails Test, Geriatric Depression Screen (GDS) and one year Clinician Global Impression of Change (CGIC) data from the baseline and 52 week visits were included. Linear regression was used to relate baseline values and annual clinical rating scale changes to annual regional vMRI changes (whole brain, ventricular, midbrain and superior cerebellar peduncle volumes).ResultsEffect sizes (Cohen's d) measuring disease progression over one year were largest for vMRI (midbrain [1.27] and ventricular volume [1.31]) but similar to PSPRS (1.26). After multiple comparison adjustment, annual changes in PSPRS, RBANS, SEADL, Color Trails Test, GDS and one year CGIC were modestly correlated with annual vMRI changes (p < 0.05). Baseline neuropsychological status on RBANS (p = 0.019) and Color Trails (p < 0.01) predicted annual midbrain atrophy rates.ConclusionStandard vMRI measurements are sensitive to disease progression in large, multicenter PSP clinical trials, but are not well correlated with clinical changes. vMRI changes may be useful as supportive endpoints in PSP trials.     

Risk factors for falls during treatment of late-life depression

BACKGROUND: Prior studies have found that antidepressant medications are associated with an increased risk of falling in elderly persons. However, little is known about the prevention of falls during treatment for depression in elderly persons. This study evaluated the time course and potential risk factors for falls in a treatment protocol for late-life depression to identify specific at-risk periods and risk factors for falls in this population. METHOD: One hundred four subjects aged 69 years and over were treated in a protocolized manner using paroxetine and interpersonal psychotherapy. Those who did not respond received augmentation therapy with bupropion, nortriptyline, or lithium. Subjects were assessed at baseline and weekly during treatment; demographic and clinical characteristics of those who experienced a fall during treatment were compared with those who did not fall. Cox proportional hazards models were used to define risk factors for falls in univariate and multivariate models. RESULTS: During a mean of 21 weeks of treatment, 40 subjects (38%) fell. About half (53%) of the subjects fell during the first 6 weeks of treatment. In the multivariate model, memory impairment and orthostatic changes in blood pressure during treatment were risk factors for falling. Additionally, augmentation with bupropion appeared to be a risk factor for falls in univariate analysis, but this result is preliminary due to the small number of subjects who took bupropion. CONCLUSION: Increased monitoring for falls is warranted during the acute treatment of late-life depression. When treating such patients, clinicians should be especially watchful of those with memory impairments or those who develop orthostatic blood pressure changes; orthostatic blood pressure should be measured throughout acute treatment. Additionally, augmenting paroxetine with bupropion may also increase the risk of falls, and this medication combination should be used with caution in elderly patients.     

Urate and risk of Alzheimer's disease and vascular dementia: A population-based study

IntroductionLow serum urate (sU) has been suggested to increase the risk of dementia since a reduction might impair antioxidant capacity. On the other hand, high sU is associated with increased cardiovascular risk which might increase the risk of dementia, especially for vascular dementia.MethodsIn 1968–1969, a population-based sample of 1462 women aged 38 to 60 years was examined and were followed up over 44 years (mean 33.1 years). We examined whether sU (determined in 1968–1969 and 1992–1994) is associated with risk of late-life dementia.ResultsDuring 44 years of follow-up, a higher sU (per standard deviation of 76.5 μmol/L) was associated with lower risk for dementia (n = 320; hazard ratio [HR] 0.81; confidence interval [CI] 0.72–0.91), Alzheimer's disease (n = 152; HR 0.78; CI 0.66–0.91), and vascular dementia (n = 52; HR 0.66; CI 0.47–0.94).DiscussionOur findings support the hypothesis that sU has a protective role in the development of dementia, regardless of dementia subtype. This may have important implications in the treatment of dementia and treatment goals for hyperuricemia in patients with gout.     

Primary fatty amides in plasma associated with brain amyloid burden,hippocampal volume,and memory in the European Medical Information Framework for Alzheimer's Disease biomarker discovery cohort

IntroductionA critical and as-yet unmet need in Alzheimer's disease (AD) is the discovery of peripheral small molecule biomarkers. Given that brain pathology precedes clinical symptom onset, we set out to test whether metabolites in blood associated with pathology as indexed by cerebrospinal fluid (CSF) AD biomarkers.MethodsThis study analyzed 593 plasma samples selected from the European Medical Information Framework for Alzheimer's Disease Multimodal Biomarker Discovery study, of individuals who were cognitively healthy (n = 242), had mild cognitive impairment (n = 236), or had AD-type dementia (n = 115). Logistic regressions were carried out between plasma metabolites (n = 883) and CSF markers, magnetic resonance imaging, cognition, and clinical diagnosis.ResultsEight metabolites were associated with amyloid β and one with t-tau in CSF, these were primary fatty acid amides (PFAMs), lipokines, and amino acids. From these, PFAMs, glutamate, and aspartate also associated with hippocampal volume and memory.DiscussionPFAMs have been found increased and associated with amyloid β burden in CSF and clinical measures.     

Non-cognitive symptoms of dementia in nursing homes: frequency,course and consequences

Abstract. Background: Since most studies concerning the frequency of non-cognitive symptoms of dementia are based on samples of psychiatric services, the results of these studies may be influenced by their selection procedure. For this reason, we investigated the frequency of non-cognitive dementia symptoms based on an epidemiological nursing home study. Methods: The sample consisted of 249 nursing home residents in Austria who were interviewed with the Clinical Interview Schedule within 2 weeks after admission (T1) and again 6 months later (T2). For the analyses of the non-cognitive symptoms among the demented, only manifest clinical abnormalities observed during the interview were included. Further, mobility and impaired self-care were assessed. Results: At admission, dementia was found in 63.9% of the sample. At T1, 38%, and at T2, 36.1% of the demented suffered from any non-cognitive symptoms. Flattened or incongruous affect, suspiciousness or aggressiveness, and anxiety were found most frequently. Multiple regression analyses showed that non-cognitive symptoms increase the risk for impaired self-care. Discussion: Despite the fact that the frequency of several non-cognitive symptoms found in our survey is lower than reported from studies based on psychiatric samples, a high proportion of the demented in nursing homes suffer from such symptoms. Non-cognitive symptoms of dementia increase the risk for an impaired self-care, which supports the assumption that they raise the costs of caring.     

Using machine learning-based analytics of daily activities to identify modifiable risk factors for falling in Parkinson’s disease

BackgroundAlthough risk factors that lead to falling in Parkinson's disease (PD) have been previously studied, the established predictors are mostly non-modifiable. A novel method for fall risk assessment may provide more insight into preventable high-risk activities to reduce future falls.ObjectivesTo explore the prediction of falling in PD patients using a machine learning-based approach.Method305 PD patients, with or without a history of falls within the past month, were recruited. Data including clinical demographics, medications, and balance confidence, scaled by the 16-item Activities-Specific Balance Confidence Scale (ABC-16), were entered into the supervised machine learning models using XGBoost to explore the prediction of fallers/recurrent fallers in two separate models.Results99 (32%) patients were fallers and 58 (19%) were recurrent fallers. The accuracy of the model to predict falls was 72% (p = 0.001). The most important factors were item 7 (sweeping the floor), item 5 (reaching on tiptoes), and item 12 (walking in a crowded mall) in the ABC-16 scale, followed by disease stage and duration. When recurrent falls were analysed, the models had higher accuracy (81%, p = 0.02). The strongest predictors of recurrent falls were item 12, 5, and 10 (walking across parking lot), followed by disease stage and current age.ConclusionOur machine learning-based study demonstrated that predictors of falling combined demographics of PD with environmental factors, including high-risk activities that require cognitive attention and changes in vertical and lateral orientations. This enables physicians to focus on modifiable factors and appropriately implement fall prevention strategies for individual patients.     

Balance confidence and functional mobility are independently associated with falls in people with Parkinson’s disease

The present study aimed to examine the association of falls with self-perceived balance confidence level, and balance and mobility performance in patients with Parkinson’s disease (PD). Forty-nine healthy subjects and 71 subjects with PD completed the study. Among the PD patients, 33 (46%) were fallers and 38 were non-fallers. All subjects were tested with the activities-specific balance confidence scale (ABC), one-leg-stance test (OLS), and timed-up-and-go test (TUG). Results indicated that PD fallers had significantly lower ABC scores, shorter OLS times and longer times to complete TUG than PD non-fallers (P < 0.05). Having a high ABC score (>80) was significantly associated with a lower fall risk, after adjusting for age, gender, and duration of PD, and for depression [odds ratio (OR) = 0.06, P = 0.020]. For performance-based measures of balance and mobility, a longer TUG time (≥16 s) was independently associated with increased risk of falling after controlling for relevant factors (OR = 3.86, P = 0.043); OLS time, however, was not significantly associated with falls. A lower self-perceived balance confidence level and a prolonged time to complete TUG were associated with increased risk of falling in patients with PD. Interventions to improve these modifiable risk factors could be useful in reducing future falls in the PD population and will require further study.     

Impaired attention predicts falling in Parkinson's disease

BackgroundCognitive deficits, in particular deficits of attention and executive function, may affect postural sway and balance in Parkinson's disease (PD). Our objective was to determine whether measures of attention were associated with falls in a large cohort of subjects with PD studied prospectively.MethodsPatients meeting UK PD Society Brain Bank Criteria were included. Assessment included UPDRS III and the Cognitive Drug Research computerised assessment battery (CDR) from which Power of Attention, Continuity of Attention, cognitive reaction time and reaction time variability were derived. Falls were assessed prospectively using monthly fall diaries returned over a year following baseline assessment.ResultsOne hundred and sixty four subjects completed fall diary datasets. One hundred and three (63%) fell one or more times during the 12 month period. Regression analysis revealed an association of fall frequency with poorer Power of Attention and increased reaction time variability, which was retained after correcting for UPDRS scores.ConclusionsReduced power of attention and increased reaction time variability are associated with increased fall frequency in PD. This has implications for the identification of those most at risk of falling, and for the management and prevention of falls in this patient group.     

Motor impairment predicts falls in specialized Alzheimer care units

We sought to identify clinical risk factors for falls in people with advanced Alzheimer disease (AD) in a prospective longitudinal observational study set in specialized AD care units. Forty-two patients with probable or possible AD were recruited. Age, sex, Mini-Mental Status Examination, Clinical Dementia Rating Scale, Neuropsychiatric Inventory/Nursing Home, Morse Fall Scale (MFS), modified Unified Parkinson's Rating Scale (mUPDRS), and gait parameters using a GAITRite Gold Walkway System with and without dual-task performance were examined. Time to a first fall was the primary outcome measure, and independent risk factors were identified. Participating subjects were old (non-fallers age, 82.3 +/- 6.7 years; fallers: 83.1 +/- 9.6 years; p = 0.76) and predominantly women (36 female/6 male). Fallers did not differ from non-fallers on any parameter except the MFS (non-fallers: 35.6 +/- 26.1; fallers: 54.4 +/- 29.8; p = 0.04), the UPDRS (non-fallers: 4.75 +/- 3.98; fallers: 7.61 +/- 4.3, p = 0.03) and cadence (steps per minute: non-fallers: 102.3 +/- 12.3; fallers: 91.7 +/- 16, p = 0.02). Fallers and non-fallers were equally affected by dual-task performance. The hazard ratios for MFS, UPDRS, and cadence were not affected by adjusting for age, sex, MMSE, or NPI scores. In conclusion, falls in advanced AD can be predicted using simple clinical measures of motor impairment or cadence. These measures may be useful for targeting interventions.