Abstract/Text: Freezing of gait (FOG) is frequently considered as one of the dopamine-resistant motor symptoms of Parkinsonism. Recent studies have clearly demonstrated that the Off-related FOG is improved by levodopa (L-dopa) or entacapone treatment. L-dopa can decrease duration of each FOG episode as well as its frequency. On-related FOGs are not common and difficult to diagnose. Only in the most advanced stages of the disease, FOGs are resistant to treatment as many other symptoms. Off-related FOGs are likely to be improved by dopamine agonists (DAs), but this has never been looked at systematically. In contrast, DA treatment might provoke FOG, and in two pivotal studies when DAs were compared to L-dopa in early stages of Parkinson's disease, the DA-treated arms experienced more FOGs. MAO-B inhibitors (selegiline and rasagiline) can decrease FOG frequency or severity, but its clinical significance is still unknown. L-Threo-DOPS has been reported to have a symptomatic beneficial effect in patients with pure freezing syndrome, but small-scale, controlled trials in Parkinson's disease could not support those early observations. Botulinum toxin injected into the calf muscles has been suggested to have a symptomatic benefit. However, double-blind, prospective studies could not support that early observation and increased fall risk in the injected patients has put this direction of treatment on hold. The potential benefit of amantadine, antidepressive drugs, acetylcholine esterase inhibitors, and methylphenidate on FOG has been studied in small-scale studies, and there is a need for prospective studies to understand the future role of those drugs.

(c) 2008 Movement Disorder Society.

Abstract/Text: To revalidate the Freezing of Gait Questionnaire (FOG-Q), patients with Parkinson's disease (PD) were randomly assigned to receive rasagiline (1 mg/day) (n = 150), entacapone (200 mg with each dose of levodopa) (n = 150), or placebo (n = 154). Patients were assessed at baseline and after 10 weeks using the FOG-Q, Unified Parkinson's Disease Rating Scale (UPDRS), Beck Depression Inventory (BDI), and Parkinson's Disease Questionnaire (PDQ-39). FOG-Q dimensionality, test-retest reliability, and internal reliability were examined. Convergent and divergent validities were assessed by correlating FOG-Q with UPDRS, BDI, and PDQ-39. Comparisons between FOG-Q item 3 and UPDRS item 14 were also made. Principal component analysis indicated that FOG-Q measures a single dimension. Test-retest reliability and internal reliability of FOG-Q score was high. FOG-Q was best correlated to items of the UPDRS relating to walking, general motor issues, and mobility. Correlations between baseline and endpoint suggested that FOG-Q item 3 is at least as reliable as UPDRS item 14. At baseline, 85.9% of patients were identified as "Freezers" using FOG-Q item 3 (> or =1) and 44.1% using UPDRS item 14 (> or =1) (P < 0.001). FOG-Q was a reliable tool for the assessment of treatment intervention. FOG-Q item 3 was effective as a screening question for the presence of FOG.