Clinical Measures for Therapeutic Intervention in Huntington’s Disease Muratori, LM 1, Marder, K 2, Louis, ED 2, Moskowitz CM 2 and Rao, AK 2 1 Department of Physical Therapy, Stony Brook University, Stony Brook, NY 2 Columbia University Medical Center, NY, NY Clinical Measures for Therapeutic Intervention in Huntington’s Disease Muratori, LM 1, Marder, K 2, Louis, ED 2, Moskowitz CM 2 and Rao, AK 2 1 Department of Physical Therapy, Stony Brook University, Stony Brook, NY 2 Columbia University Medical Center, NY, NY Methods Introduction Clinical Implications Longitudinal analysis of brain morphology in Huntington’s disease (HD) shows unremitting deterioration of tissue in important motor areas. 1 Motor impairment in HD is associated with loss of postural control 2 and decreased independence in ambulation is a significant predictor of nursing home placement. 3 Thus, clinicians are challenged to identify and implement therapies aimed at retarding this degeneration. Pilot work has shown that physical therapy for individuals with HD can decrease the effects of motor impairments and improve quality of life. 4 While several authors have addressed possible causes of impairments in gait and balance in HD e.g., 5,6, less is known about which assessment tools might be useful in clinical decision making for therapeutic intervention. Purpose Quantitative gait measurements have been correlated with disease progression 5. However, instrumented gait analysis systems like the GaitRite© are not readily available in clinics. Therefore, we tested widely used standardized clinical tests with findings from the GaitRite© to determine the utility of these tests for evaluation in HD. Gait velocity correlated with clinical measures of balance Conclusions This study was approved by the Institutional Review Board of NYS Psychiatric Institute and Columbia University Medical Center. All subjects provided informed consent prior to participation. Procedure: Subjects were given an evaluation that included fall history, gait assessment, balance, functional mobility, and self- assessments of function and well-being. In addition, dynamometry was used to assess isometric strength of the upper and lower extremities. Data Analysis: Pearson correlations were calculated for each of the clinical tests with measures of gait (recorded using the GaitRite©) and the Total Functional Capacity (TFC). Subjects Berg Balance Scale – A falls risk assessment that measures fourteen tasks, including transfers (e.g., sit to stand), retrieving objects from the floor, turning 360°, tandem stance, reaching forward while standing, and standing on one foot. Functional Reach Test – A measure of balance that uses the difference, in inches, between arm’s length and maximum forward reach, using a fixed base of support. A reach of 6 inches or less is considered a predictor of falls. Symbol Digit Modality Test – a test of visual-motor speed and cognitive function requiring the decoding of visual symbols using a paired template. Timed Up and Go (TUG) – A screening tool developed to identify individuals with balance deficits, this test measures the time taken to complete the following series of tasks: standing up from a seated position, walking 3 meters, turning, stopping, and sitting down. Total Functional Capacity (TFC) - A standardized scale used in HD to assess capacity to work, handle finances, perform domestic chores and self-care tasks, and live independently. The TFC scale ranges from 13 (normal) to 0 (severe disability). Clinical Measures References Total functional capacity (TFC) correlated with clinical measures Analysis of gait velocity showed that as subjects’ ambulation speed decreased there was a greater risk for balance problems and falls. Individuals with HD show a strong relationship between functional capacity and measures of balance, cognition, and visual-motor ability. 1 Aylward EH, Li Q, Stine OC, Ranen N, Sherr M, et al (1997) Longitudinal change in basal ganglia volume in patients with Huntington's disease. Neurology 48: Tian J, Herdman, SJ, Zee DS, Folstein SE. (1992) Postural stability in patients with Huntington’s disease. Neurology 42: Wheelock VL, Tempkin T, Marder K, et al. (2003) Predictors of nursing home placement in Huntington’s disease. Neurology 60: Quinn L, Rao AK (2002) Physical therapy and Huntington’s disease: current perspectives and case report. Neurology Report 26: Churchyard AJ, Morris ME, Georgiou N et al. (2001) Gait dysfunction in Huntington’s disease: parkinsonism and a disorder of timing. Implications for movement rehabilitation. Adv Neurol 87: Louis ED, Lee P, Quinn L, Marder K (1999) Dystonia in Huntington’s disease: prevalence and clinical characteristics. Mov Disord 14: Thirty individuals with clinically confirmed HD were tested. Gender: 16 males and 14 females Stage of disease: 10 stage I, 10 stage II, 10 stage III Age Range:Stage 1 range 30-60years, median 52yo Stage 2 range 30-71years, median 55yo Stage 3 range 34-69years, median 46yo Years since symptom onset: stage I – 5 years stage 2 – 7 years stage 3 – 10 years 1. Objective measures of gait are sensitive to disease progression in HD and are well- correlated with standardized clinical tests. 2.Scales which are validated for use to assess falls risk and balance are particularly useful to evaluate functional status in patients with HD. 3.Self-assessments of function and well-being (SF-36) are in line with clinical evaluation. 4.Tests of isometric strength are NOT well correlated with functional capacity or risk of falls in patients with HD. 1.Standardized clinical tests already familiar to clinicians working with patients with movement disorders can be used for clinical decision making in HD. 2.Areas of deficit correlated to disease progression, particularly reaching out of ones base of support, unilateral stance, and turning, may be useful to target during therapeutic intervention. 3.Strengthening should take place within a functional context to maximize benefits.