14 November 2011
Josiah AF, Gruber-Baldini AL, Anderson KE,
Fishman PS, Weiner WJ, Reich SG, Shulman LM
Objective: To compare the effects of gait impairment without
freezing of gait (FOG) versus FOG without gait impairment in Parkinson’s
disease (PD) on disability and quality of life.
Background: FOG
is frequently characterized as the major cause of gait-related
disability in PD. However, gait impairment may also result from other PD
symptoms including slowing, motor asymmetry, gait variability, dystonia
or stooped posture.
Methods: The Unified Parkinson’s
Disease Rating Scale (UPDRS), Older Americans Resources and Services
Disability Scale (OARS) and the SF-12 Health Status Survey were used to
evaluate patients with PD. Responses to UPDRS Items #14 (Freezing) and #
29 (Gait) were used to create 4 subgroups: 1) No FOG or gait
impairment, 2) FOG, no gait impairment, 3) Gait impairment, no FOG, and
4) Both FOG and gait impairment. Disease severity, disability, and
quality of life were compared across the subgroups with ANOVAs, and
between subgroups with t-tests.
Results: 916 PD patients were divided into 4 subgroups based on their gait and freezing score (#1: n = 213, #2: n = 41, #3: n = 323 and #4: n = 339). Total UPDRS progressively increased from Group 1 through Group 4 (1 = 25.2, 2 = 33.7, 3 = 39.2, 4 = 59.2; p < 0.001). Motor UPDRS also progressively increased (1 = 17.4, 2 = 19.7, 3 = 26.9, 4 = 36.5; p < 0.0001).
Similarly, disability and health-related quality of life progressively
increased from Group 1 through Group 4 (Total OARS: 1 = 15.3, 2 = 17.2,
3 = 18.9, 4 = 28.4; p < 0.001). Group 3 (Gait impairment, no
FOG) showed greater disease severity than Group 2 (FOG, no gait
impairment; Total and Motor UPDRS; p < 0.05), but the difference did not reach significance for disability or quality of life.
Conclusions: Gait
impairment without FOG was associated with greater disease severity
than FOG without gait impairment. The combination of gait impairment and
FOG was associated with the greatest disease severity and disability.
These results show differential effects of diverse features of gait
impairment in PD and demonstrate the importance of gait features
unrelated to freezing.
