RESUMEN
BACKGROUND: The purpose of this work was to study the performance and reliability of a test of fast alternating forearm movements and its relationship with measures of lower extremity function in older women with dementia. METHODS: Fast alternating movements was studied in 26 female patients (mean age 81.7 ± 5.9 years) with dementia and 34 controls (mean age 87.5 ± 4.7 years). Subgroup analyses for those aged 80-89 years were performed due to significant differences in the mean ages of the study groups. Test-retest reliability for alternating forearm movements was studied in 11 patients (mean age 80.3 ± 6.7 years) and 10 controls (mean age 87.4 ± 1.6 years). Pulses generated were transformed to an analog signal shown on a modified electrocardiogram. Numbers of cycles at 10 and 15 seconds were calculated for the right and left hand. Walking 2 × 15 m and the Get-Up-and Go (GUG) test were performed at self-selected and maximal speed. Associations between tests of upper and lower extremity function were sought in eight patients (mean age 85 ± 2.7 years) and 16 controls (mean age 85.1 ± 2.8 years) and also according to types of dementia in nine patients with probable Alzheimer's disease and 10 patients with other types of dementia. RESULTS: Patients with dementia could perform the test and had significantly fewer cycles (P = 0.02-0.006) at both 10 and 15 seconds compared with controls after age adjustment. A higher number of cycles was associated with higher self-selected walking speeds in patients (r = -0.79). Test-retest reliability for alternating forearm movements was high for both patients (intraclass correlation 0.88-0.94) and controls (intraclass correlation 0.74-0.94). CONCLUSION: Alternating forearm movements at fast speed can be used as a reliable test in both patients with dementia and healthy older subjects. The test can be used as a measure of bradykinesia and might be useful as a proxy for lower extremity function in older persons with dementia when testing of the lower extremities is not applicable due to walking disability.
Asunto(s)
Demencia/fisiopatología , Antebrazo , Extremidad Inferior , Movimiento , Anciano , Anciano de 80 o más Años , Femenino , Marcha , Humanos , Masculino , Reproducibilidad de los Resultados , Factores de Tiempo , CaminataRESUMEN
PURPOSE: To investigate whether separate physical tests of the lower extremities, that assess movement speed and postural control, were associated with cognitive impairment in older community-dwelling subjects. SUBJECTS AND METHODS: In this population-based, cross-sectional, cohort study, the following items were assessed: walking speed, walking 2 × 15 m, Timed Up and Go (TUG) at self-selected and fast speeds, one-leg standing, and performance in step- and five chair-stand tests. The study comprised 2115 subjects, aged 60-93 years, with values adjusted for demographics, health-related factors, and comorbidity. Global cognitive function was assessed using the Mini-Mental State Examination (MMSE), and cognitive impairment was defined by the three-word delayed recall task of the MMSE. Subjects who scored 0/3 on the three-word delayed recall task were defined as cases (n = 328), those who scored 1/3 were defined as intermediates (n = 457), and the others as controls (n = 1330). RESULTS: Physical tests performed rapidly were significantly associated with cognitive impairment; this was the case in increased time of five chair stands (P = 0.009, odds ratio [OR] = 1.03), TUG (P < 0.001, OR = 1.11) and walking 2 × 15 m (P < 0.001, OR = 1.05). Inability to stand on one leg for 10 seconds was associated with increased risk of being a case (P < 0.001, OR = 1.78), compared to those able to stand for 30 seconds or longer. More steps during the step test (P < 0.001, OR = 0.95) and higher fast walking speed (P < 0.001, OR = 0.51) were associated with lower risk of being a case. CONCLUSION: Slower movements and reduced postural control were related to an increased risk of being cognitively impaired. All tests that were performed rapidly were able to separate cases from controls. These findings suggest that physical tests that are related to lower extremity and postural control, emphasizing velocity, might be useful in investigating relationships between physical and cognitive function; furthermore, they can be used to complement cognitive impairment diagnoses.