Characterization of freezing of gait subtypes and the response of each to levodopa in Parkinson's disease

Abstract

To assess the effect of levodopa on distinct freezing of gait (FOG) subtypes in patients with 'off' FOG. Nineteen patients (12 men, mean age 62.0 +/- 8.4 years) with Parkinson's disease and clinically significant FOG during 'off' states were videotaped whilst walking 130 m during 'off' and 'on' states. Three independent observers characterized the type, duration, and clinical manifestations and quantified FOG by analyzing the videotapes. Their combined mean scores were used for statistical analysis. The intra-class correlation coefficient assessed inter-observer reliability. Wilcoxon and Friedman tests evaluated differences in mean frequencies of FOG characteristics. During 'off' states, FOG was elicited by turns (63%), starts (23%), walking through narrow spaces (12%) and reaching destinations (9%). These respective values were only 14, 4, 2 and 1% during 'on' states (P < 0.011). Moving forward with very small steps and leg trembling in place were the most common manifestations of FOG; total akinesia was rare. Most FOG episodes took <10 s and tended to be shorter during 'on' states. Levodopa significantly decreased FOG frequency (P < 0.0001) and the number of episodes with akinesia (P < 0.001). Distinction amongst FOG subtypes enables evaluation of distinctive therapeutic response. Levodopa helps in reducing the frequency and duration of 'off'-related FOG.

Falls in people with Parkinson’s disease: A prospective comparison of community and home-based falls

“…Tasks such as managing doorways and negotiating small spaces are known triggers of FOG [27,28] and arguably more likely to occur when walking at home. Episodes of freezing are also more likely to occur during the "off" phase of the medication cycle [28], when people with PD may be less likely to spend time in the community. Not surprisingly, FOG was more frequently reported to contribute to falls in recurrent fallers than single fallers.…”

Gait dynamics in Parkinson’s disease: Common and distinct behavior among stride length, gait variability, and fractal-like scaling

“…These include slowed ambulation ͑in part a manifestation of bradykinesia͒ with decreased or absent arm swing, longer double limb support ͑i.e., more time with both feet spent on the ground͒, 6,[34][35][36] and impaired postural control. [37][38][39][40] One of the keys to these gait problems is the inability of patients with PD to generate sufficient stride length 6,36,41 ͑a problem that has been related to impaired scaling of amplitude͒. In fact, the reduced and shortened stride length may explain many of the continuous gait disturbances in PD including the reduced gait speed and the increased time with the feet on the ground.…”

Specific Attentional Disorders and Freezing of Gait in Parkinson’s Disease

“…The FoG and non-FoG groups were constituted according to the patients' responses to item 3 of Giladi's FoG questionnaire [27]. All included patients suffered from 'off-drug' FoG [28], defined according the clinical response of FoG with levodopa administration. All patients performed a FoG trajectory [11] composed of gait initiation, turning, going through narrow passages and performing dual tasks.…”