Application of the Unified Parkinson's Disease Rating Scale in progressive supranuclear palsy: factor analysis of the motor scale.

An important criterion in scale validation is the demonstration of a stable factor structure. The Unified Parkinson's Disease Rating Scale (UPDRS) is widely used to assess Parkinson's disease (PD). The reliability and applicability of the motor subscale of the UPDRS (UPDRSm) when applied to patients diagnosed with progressive supranuclear palsy (PSP) is unknown. In a sample of 175 patients with PSP, factor analysis revealed five clinically distinct factors: two independent bradykinesia factors (axial/gait and extremities), one rigidity factor, and two independent tremor factors (rest and action). Two items (posture and rest head tremor) did not reach criteria for factor loadings. There was a high degree of internal consistency. These results suggest that UPDRSm is a reliable and applicable scale for assessing most aspects of PSP function as well as severity measures of five clinical disability domains.     

Physiology and pathophysiology of the basal ganglia-thalamo-cortical networks

Low-frequency resting tremor is one of the cardinal signs of Parkinson's disease (PD) and occurs also in some of its animal models. Current physiological studies and models of the basal ganglia indicate that changes of discharge pattern and synchronization of basal ganglia neurons rather than modification in their discharge rate are crucial to the pathophysiology of PD. However, parkinsonian tremor is not strictly correlated with the synchronous oscillations in the basal ganglia networks. We therefore suggest that abnormal basal ganglia output enforces abnormal thalamo-cortical processing leading to akinesia, the main negative symptom of Parkinson's disease. The parkinsonian positive motor signs, such as tremor and rigidity, most likely evolve as a downstream compensatory mechanism.     

不同运动功能障碍对帕金森病患者日常生活活动能力的影响

目的探讨影响帕金森病(PD)患者日常生活活动(ADL)的运动症状。方法 93例PD患者接受了调查。采用PD统一评分量表第2、3、4部分,分别评估患者的ADL、运动功能障碍和运动并发症。将帕金森病综合评分量表(UPDRS)运动评分分为6部分:震颤、肌强直、动作缓慢、面部表情、语言表达和中轴(步态和姿势)损伤。采用逐步线性回归来评估患者ADL与各具体运动功能障碍之间的相关性。结果中轴损伤是PD患者UPDRS II评分最主要的预测因子,语言表达、动作缓慢和震颤也有一定的预测作用。4项因素相加能够解释72%的UPDRS II评分变化。结论 PD治疗过程中应重视患者的中轴运动损伤症状,加强康复治疗,以提高患者的ADL。     

脑白质病变对老年轻度帕金森样体征的影响

目的探讨脑白质病变（WMLs）对老年轻度帕金森样体征（MPSs）的影响。方法临床收集335名老年男性，根据MRIT2加权像将WMLs分为4级，以WMLs0级作为对照组，所有受试者进行UP—DRS运动评定，比较不同程度WMLs组UPDRS运动总评分及各单项评分之间的差异。结果（1）与WMLs0级组比较，WMLs2级组UPDRS运动总分、运动迟缓及轴性损害单项评分显著增加（P〈0．05），WMLs3级组UPDRS运动总分、强直、运动迟缓和轴性损害单项评分显著增加（P〈0．05）；与WMLs1级组比较，WMLs2级组UPDRS运动总分、轴性损害单项评分显著增加（P〈0．05），WMI。S3级组UPDRS运动总分、强直、运动迟缓及轴性损害单项评分显著增加（P〈0．05）；与WMLs2级组比较，WMLs3级组UPDRS运动总分、运动迟缓和轴性损害单项评分显著增加（P〈0．05）；（2）logistic回归分析控制了年龄、高血压病、糖尿病后，轻度帕金森样体征尤其运动迟缓和轴性损害与WMLs2～3级密切相关。结论中到重度WMLs会导致或者加重老年MPSs，尤其运动迟缓和轴性损害症状，而较少产生震颤；轻度WMLs相对是一种良性病变；积极防治WMLs可能会改善老年人的MPSs。     

Progression of parkinsonian signs in Alzheimer's disease

OBJECTIVE: To describe the progression of parkinsonian signs in persons with AD. BACKGROUND: Parkinsonian signs are common in AD and appear to be related to morbidity and mortality. However, little is known about individual patterns of progression of parkinsonian signs. METHODS: A cohort of 410 people with clinically diagnosed AD underwent annual clinical evaluations over a 4-year period, with over 90% of survivors participating in follow-up. The entire motor portion of the Unified Parkinson's Disease Rating Scale (UPDRS) was administered at each evaluation. Previously established measures of four parkinsonian signs were derived from the UPDRS. Scores ranged from 0 to 100 and represented the percent obtained of the total possible item score. RESULTS: A growth curve approach was used to estimate individual paths of change. Rates of change in bradykinesia (4.5% increase per year), rigidity (6.0% increase per year), and gait disorder/postural reflex impairment (8.9% increase per year) were substantial and positively correlated (median r = 0.69). Change in tremor was minimal, mostly confined to postural tremor, and weakly correlated with change in other signs (median r = 0.16). The rate of progression in each sign was highly variable across individuals and not strongly related to demographic factors or use of neuroleptic medications. CONCLUSIONS: Parkinsonian signs other than tremor progress rapidly in AD but at widely differing rates.     

Randomized trial of pallidotomy versus medical therapy for Parkinson's disease

Thirty-six patients with Parkinson's disease (PD) were randomized to either medical therapy (N = 18) or unilateral GPi pallidotomy (N = 18). The primary outcome variable was the change in total Unified Parkinson's Disease Rating Scale (UPDRS) score at 6 months. Secondary outcome variables included subscores and individual parkinsonian symptoms as determined from the UPDRS. At the six month follow-up, patients receiving pallidotomy had a statistically significant reduction (32% decrease) in the total UPDRS score compared to those randomized to medical therapy (5% increase). Following surgery, patients' showed improvement in all the cardinal motor signs of PD including tremor, rigidity, bradykinesia, gait and balance. Drug-induced dyskinesias were also markedly improved. Although the greatest improvement occurred on the side contralateral to the lesion, significant ipsilateral improvement was also observed for bradykinesia, rigidity and drug-induced dyskinesias. A total of twenty patients have been followed for 2 years to assess the effect of time on clinical outcome. These patients have shown sustained improvement in the total UPDRS (p < 0.0001), "off" motor (p < 0.0001) and complications of therapy subscores (p < 0.0001). Sustained improvement was also seen for tremor, rigidity, bradykinesia, percent on time and drug-induced dyskinesias.     

Axial parkinsonian symptoms can be improved: the role of levodopa and bilateral subthalamic stimulation

OBJECTIVE: To assess the effects of high frequency stimulation of the subthalamic nucleus (STN) on axial symptoms occurring in advanced stages of Parkinson's disease (PD). METHODS: The efficacy of STN stimulation on total motor disability score (unified Parkinson's disease rating scale (UPDRS) part III) were evaluated in 10 patients with severe Parkinson's disease. The subscores were then studied separately for limb akinesia, rigidity, and tremor, which are known to respond to levodopa, and axial signs, including speech, neck rigidity, rising from a chair, posture, gait, and postural stability, which are known to respond less well to levodopa. Patients were clinically assessed in the "off" and "on" drug condition during a levodopa challenge test performed before surgical implantation of stimulation electrodes and repeated 6 months after surgery under continuous STN stimulation. A complementary score for axial symptoms from the "activities of daily living" (ADL)-that is, speech, swallowing, turning in bed, falling, walking, and freezing-was obtained from each patient's questionnaire (UPDRS, part II). RESULTS: Improvements in total motor disability score (62%), limb signs (62%), and axial signs (72%) obtained with STN stimulation were statistically comparable with those obtained with levodopa during the preoperative challenge (68%, 69%, and 59%, respectively). When levodopa and STN stimulation were combined there was a further improvement in total motor disability (80%) compared with preoperative levodopa administration. This consisted largely of an additional improvement in axial signs (84%) mainly for posture and postural stability, no further improvement in levodopa responsive signs being found. Axial symptoms from the ADL showed similar additional improvement when levodopa and STN stimulation were combined. CONCLUSION: These findings suggest that bilateral STN stimulation improves most axial features of Parkinson's disease and that a synergistic effect can be obtained when stimulation is used in conjunction with levodopa treatment.     

Parkinsonism in multiple system atrophy: natural history, severity (UPDRS-III), and disability assessment compared with Parkinson's disease.

We analyzed parkinsonian features in multiple system atrophy (MSA) compared with age- and disease duration-matched Parkinson's disease (PD) patients, and assessed the applicability of the Unified Parkinson's Disease Rating Scale (UPDRS) -III motor scale as a means of rating their severity. Cross-sectional analysis of parkinsonism was done using UPDRS-III, International Cerebellar Atatia Rating Scale, and disability scales (Hoehn and Yahr [H&A], Schwab and England, Katz and Lawton) in 50 unselected MSA patients and in 50 matched PD patients. At symptom onset, falls occurred 10 times more frequently in MSA, whereas limb tremor was 10 times more common in PD. At first visit (10.2 months), hemiparkinsonism and pill-rolling rest tremor were less common in MSA. Hypomimia, atypical rest, postural or action tremor, as well as postural instability were more frequent in MSA. At study examination (62.4 months), parkinsonian signs in MSA patients were more frequently symmetrical and associated with axial rigidity, antecollis and postural instability. A levodopa response of >50% was seen in <10% of MSA patients. Modified H&Y stages (3.2 +/- 1.3 vs. 2.2 +/- 0.78) and UPDRS-III scores (48.14 +/- 19.5 vs. 31.74 +/- 12.9) were significantly (P = 0.0001) higher in MSA. The internal consistency of the UPDRS-III was fair in MSA patients (Cronbach's alpha >0.90), and correlated well with marked dependency on the Schwab and England and Katz and Lawton scales. Factor structure analysis of UPDRS-III in MSA showed five clinically distinct subscores accounting for 74% of the variance, differing from PD by the dependency of the face-speech and limb bradykinesia items and independence of the postural-action tremor from the rest tremor items. There was a significant correlation (R(2) = 0.70, P = 0.001) between ICARS ataxia and UPDRS-III scores in MSA patients. Results confirm a distinct profile of parkinsonism in MSA and greater severity and disability compared with PD. It also indicates that the UPDRS-III provides a useful severity measure of parkinsonism in MSA, albeit contaminated by additional cerebellar dysfunction.     

Lack of motor symptoms progression in Parkinson's disease patients with long-term bilateral subthalamic deep brain stimulation

To evaluate the long-term progression of motor symptoms in Parkinson's disease (PD) patients treated with subthalamic nucleus deep brain stimulation (STN-DBS), we retrospectively analyzed data from 50 PD patients with bilateral STN-DBS. Clinical records at baseline and at several yearly intervals were reviewed. The Unified Parkinson's Disease Rating scale (UPDRS) was performed preoperatively after withholding medications for at least 12 hr (OFF) and after taking the usual dose of levodopa. Postoperative evaluations were completed in four clinical states: OFF medications—stimulators OFF (OFF/OFF); OFF medications—stimulators ON; ON medications—stimulators OFF; and ON medications—stimulators ON. The UPDRS motor scores OFF/OFF were virtually unmodified up to 5 years when compared with preoperative OFF scores. There was no significant difference between OFF/OFF score variations from baseline in patients with shorter (<11 years) and longer PD duration at the time of surgery. No consistent deterioration from untreated baseline was noted for each UPDRS motor subscore (tremor, rigidity, bradykinesia, and axial). Untreated PD motor scores did not worsen over time in patients undergoing STN-DBS, suggesting that there is no progression of motor severity. These results could be explained either by a natural stabilization of PD motor symptoms after many years or neuroprotective properties of STN-DBS.     

Mild Parkinsonian signs are associated with lower olfactory test scores in the community‐dwelling elderly

Mild Parkinsonian signs (MPS, impaired gait, rigidity, bradykinesia, rest tremor) are commonly found during the clinical examination of older people and may be a precursor to Parkinson's disease (PD) or Alzheimer's disease (AD). Marked deficits in olfaction occur in PD and AD. The objective of this study was to determine whether University of Pennsylvania Smell Test (UPSIT) scores were lower in nondemented community‐dwelling elderly with versus without MPS. Nondemented persons age ≥65 years without PD in Washington Heights‐Inwood, NY were evaluated with an abbreviated motor Unified PD Rating Scale and a 40‐item UPSIT. Lower UPSIT and higher transformed UPSIT score (square root [UPSIT ‐ 41]) indicated greater olfactory dysfunction. One‐hundred‐seventy‐seven (16.4%) of 1,078 participants had MPS. Mean UPSIT scores (MPS vs. without MPS) were 24.3 ± 7.1 versus 26.4 ± 6.8, P < 0.001. In a logistic regression analysis adjusting for age and education, transformed UPSIT score was associated with MPS (OR 1.25, 95% CI 1.04–1.52, P = 0.02). In an adjusted logistic regression analysis, participants with higher transformed UPSIT scores (based on a median split) were 1.55 times more likely to have MPS than were those with lower scores (P = 0.01). Within transformed UPSIT score quartiles, the odds of having MPS were 1.0 (reference), 1.35, 2.02, and 2.20 (P < 0.05). The association with transformed UPSIT scores was similar across MPS subtypes (axial dysfunction, rigidity, tremor).MPS were associated with a mild reduction in olfactory function. These observations further support the view of MPS as a marker of emerging degenerative brain pathologies. © 2007 Movement Disorder Society     

Cerebral cortical areas in which thickness correlates with severity of motor deficits of Parkinson’s disease

The pathology of Parkinson’s disease (PD) is not confined to the nigrostriatal dopaminergic pathway, but also involves widespread cerebral cortical areas. Such non-nigrostriatal lesions may contribute to disabling dopa-resistant parkinsonian motor deficits. We performed cortical thickness analysis to identify cerebral cortical brain areas in which thickness correlates with the severity of parkinsonian motor deficits. We performed T1-weighted brain magnetic resonance imaging studies in 142 PD patients. Motor scores on the Unified Parkinson’s Disease Rating Scale (UPDRS) were measured, and subscores were calculated for bradykinesia, rigidity, tremor, and axial motor deficits. Using FreeSurfer software, we studied cortical areas in which thickness correlates with disease duration or the severity of parkinsonian motor deficits. The cortical thickness of the parieto-temporal association cortex, including the inferior parietal and posterior parietal cortices, showed a negative correlation with disease duration, total UPDRS motor score, and UPDRS subscores for bradykinesia and axial motor deficits. We found no cortical areas in which thickness correlated with subscores for tremor and rigidity. In addition to nigrostriatal dopaminergic deficit, progressive thinning of the parieto-temporal sensory association cortices related to disease duration seems to be related in part to the exacerbation of bradykinesia and the axial motor symptoms of PD.     

Diagnosing Parkinson's disease using videotaped neurological examinations: validity and factors that contribute to incorrect diagnoses.

Field work is commonly required in movement disorders research. Sending neurologists into the field can be logistically challenging and costly. Alternatively, neurological examinations may be videotaped and reviewed later. There is little knowledge of the validity of the videotaped neurological examination in the diagnosis of Parkinson's disease (PD). We examined the validity of the videotaped Unified Parkinson's Disease Rating Scale (UPDRS) motor examination in the diagnosis of PD, and sought to determine which factors are associated with incorrect diagnoses. PD patients and controls were enrolled in a familial aggregation study between August of 1998 and June of 2000, and as part of that study each was examined by a physician who performed an in-person UPDRS motor examination. Each also underwent a second, videotaped UPDRS motor examination. Based on the review of this videotape, a neurologist, who was blinded to the previous clinical diagnosis, assigned a diagnosis of PD or normal. A total of 211 of 231 PD patients (sensitivity = 91.3%), and 170 of 172 controls (specificity = 98.8%) were correctly identified based on the videotape. True positives had a higher mean rest tremor score (1.7 vs. 0.3; P < 0.001), action tremor score (0.9 vs. 0.3; P < 0.001), bradykinesia score (11.2 vs. 7.4; P = 0.02), and disease of longer mean duration (8.9 vs. 5.8 years; P = 0.001) than false negatives. False negatives did not differ from true positives in terms of age, total dose of levodopa, Hoehn and Yahr score, or rigidity, gait and posture, or facial masking scores (each assessed during the in-person examination). The videotaped UPDRS motor examination is a useful means of diagnosing PD and provides an alternative approach for the diagnosis of PD in field studies. A limitation is that patients with milder PD of shorter duration may not be recognized as PD.     

Unilateral thalamotomy for the treatment of tremor dominant Parkinson's disease

BACKGROUND AND PURPOSE: To assess the effectiveness of unilateral thalamotomy for the treatment of parkinsonian tremor and other motor signs of Parkinson's disease (PD). MATERIAL AND METHODS: Between 1999 and 2004, 41 patients with idiopathic tremor dominant PD were treated surgically in the Neurosurgical Department of Postgraduate Medical Center in Warsaw. Stereotactic thalamotomy was performed with Leksell stereotactic frame (model G) using intraoperative macrostimulation. The patients were assessed according to the Unified Parkinson's Disease Rating Scale version 3. (UPDRS) before and after thalamotomy in the off state. The progression of PD was also evaluated according to the Hoehn and Yahr scale in the off state and also Schwab and England was used to assess the disability of the patients. The patients were evaluated before thalamotomy in the off state, and 3, 12, 24 and 36 months after surgery, according to the above mentioned clinical rating scales. RESULTS: The authors report their results among 41 patients who underwent stereotactic thalamotomy 3 years postoperatively. At 3 years follow-up (in the group of 19 patients) the contralateral tremor from the presurgical value of 11.2 (items 20 - 21 UPDRS) decreased to 2.6. The rigidity in contralateral limbs at 3 years follow-up was 1.7 (item 22 UPDRS) when compared to 2.8 (item 22 UPDRS) preoperative value. Thalamotomy had no effect on bradykinesia or other manifestations of PD such as balance or gait disturbance. There were 13 transient and 6 permanent complications. CONCLUSIONS: Thalamotomy using intraoperative macrostimulation in carefully selected patients is a beneficial operation for the control of medically refractory parkinsonian resting and postural tremor. The effect of unilateral thalamotomy on tremor is long lasting.     

双侧丘脑底核脑深部刺激术治疗帕金森病13例报告

目的 探讨双侧丘脑底核（STN）脑深部刺激术（DBS）治疗帕金森病的临床经验。方法 从2002年到2005年共完成了13例帕金森病的双侧丘脑底核DBS，根据STN解剖学定位，靶点的理论坐标值是X=11-13mm，Y=0-2mm，Z=0-4mm，通过立体定向技术在双侧丘脑底核植入刺激电极，并于锁骨下方植入脑深部电刺激器。结果 随访时间为6个月到3年，3例震颤为主病人的症状完全缓解，即震颤完全消失；僵直和运动迟缓为主要症状者的症状缓解程度达90％以上，其中以四肢肌肉僵直的效果较好，运动迟缓也有明显缓解，但是有1例病人双侧肢运动协调性差。所有患者植物神经功能症状有较明显改善，如便秘、流涎、出汗和浮肿等均有改善。结论 DBS治疗帕金森病，是帕金森病治疗的一个里程碑似的进步。它可以明显地缓解帕金森病的主要症状和体征，对运动迟缓、僵直和震颤等均有较理想的效果。     

Progression of gait disorder and rigidity and risk of death in older persons

BACKGROUND: Bradykinesia, gait disturbance, rigidity, and tremor are common motor signs in old age. All of these signs are associated with increased morbidity and mortality, but the extent to which they are progressive is unknown. METHODS: Study participants were 787 older Catholic clergy members without clinically diagnosed PD, related conditions, or dementia at baseline. They were evaluated annually for up to 7 years, with >95% follow-up participation by survivors. Evaluations included administration of a modified version of the motor portion of the Unified PD Rating Scale (UPDRS), from which previously established measures of the global UPDRS and four specific motor signs were derived. Scores represent the percent of the total possible UPDRS score obtained. RESULTS: At baseline, the global UPDRS score ranged from 0 to 36.3 (mean +/- SD, 7.3 +/- 6.4). It increased by an average of 0.69 unit per year during follow-up, with more rapid progression in older persons, but there was wide variability with no progression in 21% of subjects and annual increases of up to 8.23 units in the remaining 79%. Of 129 persons who died, 106 had follow-up UPDRS data. In a proportional hazards model, risk of death was associated with both the level of the global UPDRS score at baseline and the annual rate of progression (both p < 0.001). Overall, risk of death in subjects who had some worsening of the global UPDRS score was 2.93 times the rate among those without progression (95% CI, 1.32-6.50). Gait disorder/postural reflex impairment and rigidity worsened, but bradykinesia and tremor did not. Risk of death was associated with worsening of gait/posture but not with the other signs. CONCLUSION: Gait disorder and rigidity, as assessed with the modified UPDRS, are usually progressive in old age. Both the severity of the gait disorder and its rate of progression are strongly associated with risk of death.     

帕金森病患者纹状体多巴胺转运体显像与帕金森病临床量表评分的相关性

目的研究帕金森病(PD)患者纹状体多巴胺转运体(DAT)显像与PD临床量表评分的相关性。方法以99mTcTRODAT1为显像剂,用单光子发射断层扫描(SPECT)对29例PD患者进行纹状体DAT显像;应用统一PD评定量表(UPDRS)对患者的运动功能进行评分。将UPDRSⅡ(日常生活活动)、Ⅲ(运动评分)和Ⅴ(病情分期)的评分、患者年龄及病程分别与起病肢体同侧、对侧及两侧纹状体的DAT摄取值进行相关性分析。结果纹状体DAT摄取值与UPDRSⅡ、Ⅲ和Ⅴ评分、病程呈负相关(r分别为-0.70、-0.80、-0.49及-0.54,均P<0.01),与年龄无相关性(r=-0.018,P>0.05);纹状体DAT摄取值与UPDRSⅢ的肌僵直和运动迟缓评分呈负相关(r=-0.782、-0.83,均P<0.01),与震颤评分不相关。结论纹状体DAT显像是反映PD严重程度的客观指标,其与PD临床量表部分项目评分有相关性。     

Assessment of rest tremor in Parkinson's disease

BACKGROUND AND PURPOSE: Rest tremor is the most frequent sign of Parkinson's disease (PD) after bradykinesia, occurring with various severity in about 75% of patients. An objective assessment of rest tremor is difficult. The aim of the study was to analyze rest tremor in PD with the three-dimensional gauging system CMS 10; more specifically, the impact of levodopa treatment on rest tremor, the influence of clinical factors, and the correlation between rest tremor and clinical scales were assessed. MATERIAL AND METHODS: Ninety-five patients with PD (mean age 67.6 years) and 30 healthy people in a control group (mean age 59.3 years) were examined. Clinical scales (UPDRS, Hoehn and Yahr, Schwab and England, as well as Webster scale) were used to assess severity of PD. The assessment of rest tremor was performed within the more and less affected upper limb with the three-dimensional gauging system CMS 10 (Zebris GmbH) before and 1-2 hours after levodopa intake. Frequency (Hz), amplitude (deg), velocity (deg/ms) and acceleration (deg/s2) of the tremor were evaluated. Results were compared with averaged results for left and right upper limb in the control group. RESULTS: The method used in this study objectively showed asymmetry in rest tremor. After levodopa intake, all evaluated parameters of rest tremor were decreased (mainly the amplitude and frequency, and to a lesser degree, velocity and acceleration). The motor part of UPDRS showed the best correlation with rest tremor. CONCLUSIONS: The three-dimensional measuring system CMS 10 is useful in the objective assessment of rest tremor in PD. Rest tremor in PD is under the influence of PD form, the intake of levodopa dose, the amount of levodopa, gender and level of education.     

Systematic evaluation of rating scales for impairment and disability in Parkinson's disease.

We assessed the clinometric characteristics of rating scales used for the evaluation of motor impairment and disability of patients with Parkinson's disease (PD), conducting a systematic review of PD rating scales published from 1960 to the present. Thirty studies describing clinometrics of 11 rating scales used for PD were identified. Outcome measures included validity (including factor structure), reliability (internal consistency, inter-rater, and intrarater) and responsiveness. We traced three impairment scales (Webster, Columbia University Rating Scale [CURS] and Parkinson's Disease Impairment Scale), four disability scales (Schwab and England, Northwestern University Disability Scale [NUDS], Intermediate Scale for Assessment of PD, and Extensive Disability Scale), and four scales evaluating both impairment and disability (New York University, University of California Los Angeles, Unified Parkinson's Disease Rating Scale [UPDRS], and Short Parkinson Evaluation Scale). The scales showed large differences in the extent of representation of items related to signs considered responsive to dopaminergic treatment or to those signs that appear late in the disease course and lack responsiveness to treatment. Regardless of the scale, there was a conspicuous lack of consistency concerning inter-rater reliability of bradykinesia, tremor, and rigidity. Overall disability items displayed moderate to good inter-rater reliability. The available evidence shows that CURS, NUDS, and UPDRS have moderate to good reliability and validity. In contrast to their widespread clinical use for assessment of impairment and disability in PD, the majority of the rating scales have either not been subjected to an extensive clinometric evaluation or have demonstrated clinometric shortcomings. The CURS, NUDS, and UPDRS are the most evaluated, valid, and reliable scales currently available.     

Gait dynamics in Parkinson's disease: relationship to Parkinsonian features,falls and response to levodopa

OBJECTIVES: Patients with Parkinson's disease (PD) have an increased risk of falling that has yet to be fully explained. To better understand the gait disturbance in PD and the factors that contribute to falls, we quantitatively evaluated: (1) the relationship between gait variability (a marker of fall risk in other populations), fall history, and other parkinsonian features, and (2) the effects of levodopa on these relationships. METHODS: The average stride time and stride-to-stride variability were measured using force-sensitive insoles during comfortable walking. Fall frequency, motor control, function, and mental health were measured using the Unified Parkinson's Disease Rating Scale (UPDRS), the Mini-Mental State Exam (MMSE), and the timed motor tests of the Core Assessment Program for Intracerebral Transplantations (CAPIT) in 32 subjects with idiopathic PD, in an "off" (unmedicated) state and again in an "on" (medicated) state. RESULTS: Average stride time was not associated with any UPDRS or CAPIT measure and was similar in fallers and non-fallers in "off" and "on" states (p>0.27). Stride time variability was significantly associated with fall frequency as well as with total scores on the CAPIT and the UPDRS, ADL abilities, and motor function. Stride time variability and falls were not related to tremor, rigidity or bradykinesia in the "off" state. 41% of subjects reported one or more falls. Stride time variability was 8.8+/-7.9% in fallers and 4.2+/-1.3% in non-fallers (p<0.009). Stride time variability significantly improved in response to levodopa, both in fallers and non-fallers, but remained increased in fallers (vs. non-fallers). CONCLUSIONS: The patho-physiology responsible for impaired stride-to-stride regulation of gait timing is apparently independent of other cardinal features of PD, i.e., tremor, rigidity, or bradykinesia, but is responsive to levodopa. Stride-to-stride variability is especially impaired among PD subjects with a history of falls, suggesting, for the first time, the possibility of exaggerated impairment of internal clock function in PD fallers.     

Functional correlates and prevalence of mild parkinsonian signs in a community population of older people

BACKGROUND: Mild parkinsonian signs (MPS) are associated with incident dementia and an increased risk of mortality. To our knowledge, the functional correlates of MPS have not been studied. OBJECTIVES: To study the functional correlates of MPS, including self-reported and performance-based measures of function, and to determine the prevalence of MPS in a cohort of community-dwelling older people (aged >or=65 years). DESIGN: Participants (N = 1866) in the Washington Heights-Inwood Columbia Aging Project underwent a neurological assessment that included a modified motor portion of the Unified Parkinson's Disease Rating Scale, which yielded a parkinsonian sign score (range, 0-40) and parkinsonian sign subscores (axial function, rigidity, and tremor). A functional assessment included 3 self-reported measures of function and 2 performance-based tests. Participants with Parkinson disease were excluded. RESULTS: Mild parkinsonian signs were present in 469 (25.1%) of the 1866 participants. The parkinsonian sign score was correlated with functional and performance-based test scores (r = 0.24-0.32, P<.001). The axial function and rigidity subscores correlated to a greater extent with functional and performance-based test scores than did the tremor subscore. In analysis of covariance models, excluding participants with dementia and adjusting for age, sex, ethnicity, education, depressive symptoms, and medical illnesses (eg, arthritis), the parkinsonian sign score and age were strongly and independently associated with functional scores. CONCLUSIONS: Mild parkinsonian signs, and particularly axial dysfunction, were associated with functional disability, including self-reported and performance-based measures of functional difficulty. Given the high prevalence of these signs in elderly persons, MPS may be a significant indicator of disability in elderly persons.