Gait and balance in Parkinson’s disease subtypes: objective measures and classification considerations

Abstract

Parkinson's disease (PD) is often divided into tremor dominant (TD) and postural instability gait difficulty (PIGD) subtypes. However, objective measures of gait (e.g., stride length, variability) and balance have not been well studied in these subtypes. To better understand these motor subtypes, we objectively quantified gait and balance and their behavioral correlates. 110 patients with PD underwent a clinical evaluation and were stratified into PIGD and TD subtypes. Participants walked under single and dual task conditions while wearing a single body-fixed sensor, both "OFF" and "ON" medications and at home for 3 days. We also examined performance-based tests of mobility, balance, and fall risk. Stricter criteria were also applied, dividing the subjects into predominant representative subgroups: p-PIGD and p-TD. Both the PIGD (n = 62) and TD (n = 42) groups and the p-PIGD (n = 31) and p-TD (n = 32) subgroups were similar with respect to basic disease characteristics (e.g., disease duration, p > 0.69). Surprisingly gait speed, stride length, and variability did not differ between the PIGD and TD groups (p > 0.05). In contrast, the p-PIGD group had reduced gait speed (under single and dual task conditions), shorter strides, increased stride variability, and decreased stride regularity (regularity: p-PIGD 0.66 ± 0.10; p-TD 0.74 ± 0.08; p = 0.003). The p-PIGD group also scored worse on performance-based tests, compared to the p-TD. Clinical assessments of the disturbances seen in patients with the PIGD subtype are not consistent with objective measures; overlapping between the groups is seen in many objective features of gait and balance. These findings suggest that the proposed alternate classification scheme may be useful.

Contribution of Axial Motor Impairment to Physical Inactivity in Parkinson Disease

“…It may underemphasize mobility and may be a poor indicator of ambulatory function, as reported previously. 30, 31 Interpretation of our results was based on physical activity variables used in this study, and caution should be made when generalizing to other functional mobility measures.…”

Gait analysis with wearables predicts conversion to Parkinson disease

“…[15][16][17][18][19][20] The aim of this longitudinal prospective observation study over 6 years in a cohort of healthy controls (HCs) was therefore to investigate whether a comprehensive set of gait characteristics measured with wearable technology, that is, a wearable device, can define prodromal PD by (1) evaluating if gait characteristics can predict risk of conversion, (2) estimating the year-on-year change in gait characteristics, and (3) identifying the time at which changes in gait would start being evident prior to diagnosis. [15][16][17][18][19][20] The aim of this longitudinal prospective observation study over 6 years in a cohort of healthy controls (HCs) was therefore to investigate whether a comprehensive set of gait characteristics measured with wearable technology, that is, a wearable device, can define prodromal PD by (1) evaluating if gait characteristics can predict risk of conversion, (2) estimating the year-on-year change in gait characteristics, and (3) identifying the time at which changes in gait would start being evident prior to diagnosis.…”

Clinical and Pathophysiological Considerations of Gait Limitations and High Prevalence of Falls, in Elderly with Most Common, Disabling Neurological Diseases

“…Falls occurred three times more frequently in PD (in 54% of PD vs. 18% of controls) [30]. Recurrent fallers (35%) had a significantly more severe motor disability [31], worse cognitive [27] and non-motor symptoms (greater general physical fatigue, less energy levels, depressive mood) than those who did not fall [32].…”

“…Patients with the PIGD subtype (predominantly characterized by axial motor involvement and increased cognitive impairment) are predisposed to falls, contrasting with the TD subjects [27]. These clinical particularities raised the supposition of different neuropathology, genetic and etiologic influences, distinct neurotransmitter systems, and functional imaging aspects [25][26][27][28].…”

“…Cortical structures including the frontal and parietal lobes, the mesencephalic locomotor region and specifically, the pedunculopontine nuclear area, all apparently play important roles in the control of postural muscle tone and locomotion in PD [24,27]. FoG, remarkable in advanced phases of PD, might be associated with dysfunction of the fronto-basal ganglia circuit [24,33].…”