Post-polio Syndrome: More Than Just a Lower Motor Neuron Disease

There is a need for an easily administered instrument which can be applied to all patients with restless legs syndrome (RLS) to measure disease severity for clinical assessment, research, or therapeutic trials. The pathophysiology of RLS is not clear and no objective measure so far devised can apply to all patients or accurately reflect severity. Moreover, RLS is primarily a subjective disorder. Therefore, a subjective scale is at present the optimal instrument to meet this need. Twenty centers from six countries participated in an initial reliability and validation study of a rating scale for the severity of RLS designed by the International RLS study group (IRLSSG). A ten-question scale was developed on the basis of repeated expert evaluation of potential items. This scale, the IRLSSG rating scale (IRLS), was administered to 196 RLS patients, most on some medication, and 209 control subjects. The IRLS was found to have high levels of internal consistency, inter-examiner reliability, test-retest reliability over a 2-4 week period, and convergent validity. It also demonstrated criterion validity when tested against the current criterion of a clinical global impression and readily discriminated patient from control groups. The scale was dominated by a single severity factor that explained at least 59% of the pooled item variance. This scale meets performance criteria for a brief, patient completed instrument that can be used to assess RLS severity for purposes of clinical assessment, research, or therapeutic trials. It supports a finding that RLS is a relatively uniform disorder in which the severity of the basic symptoms is strongly related to their impact on the patient's life. In future studies, the IRLS should be tested against objective measures of RLS severity and its sensitivity should be studied as RLS severity is systematically manipulated by therapeutic interventions.

We assessed the validity of the Physical Activity Scale for the Elderly (PASE) in a sample of sedentary adults (56 men, 134 women, mean age +/- [SD] 66.5+/-5.3 years) who volunteered to participate in a randomized controlled trial on the effect of aerobic conditioning on psychological function. Construct validity was established by correlating PASE scores with physiologic and performance characteristics: peak oxygen uptake, resting heart rate and blood pressure, percent body fat, and balance. The mean PASE scores were higher in men than in women (men = 145.8+/-78.0; women = 123.9+/-66.3, P<0.05), and in those age 55-64 years compared with those age 65 years and over (55-64 = 144.2+/-75.8; 65 and over = 118.9+/-63.9, P<0.05). PASE scores were also significantly higher in those who did not report a chronic health condition (cardiovascular disease, hypertension, cancer, or recent surgery). PASE scores were significantly associated (P<0.05) with peak oxygen uptake (r = 0.20), systolic blood pressure (r = -0.18) and balance score (r = 0.20). No significant associations of PASE score and diastolic blood pressure, resting heart rate, or percent body fat were noted. These results provide additional evidence for the validity of the PASE as a measure of physical activity suitable for use in epidemiology studies on the association of physical activity, health, and physical function in older individuals.

People with balance disorders are characterized as having difficulty with transitional movements, such as the sit-to-stand movement. A valid and feasible tool is needed to help clinicians quantify the ability of people with balance disorders to perform transitional movements. The purpose of this study was to describe the concurrent and discriminative validity of data obtained with the Five-Times-Sit-to-Stand Test (FTSST). The FTSST was compared with the Activities-specific Balance Confidence Scale (ABC) and the Dynamic Gait Index (DGI). Eighty-one subjects without balance disorders and 93 subjects with balance disorders were recruited for the study. Each subject was asked to stand from a 43-cm-high chair 5 times as quickly as possible. The ABC and DGI scores were recorded. Subjects with balance disorders performed the FTSST more slowly than subjects without balance disorders. Discriminant analysis demonstrated that the FTSST correctly identified 65% of subjects with balance dysfunction, the ABC identified 80%, and the DGI identified 78%. The ability of the FTSST to identify subjects with balance dysfunction was better for subjects younger than 60 years of age (81%). The FTSST displays discriminative and concurrent validity properties that make this test potentially useful in clinical decision making, although overall the ABC and the DGI are better than the FTSST at discriminating between subjects with and subjects without balance disorders.