Comorbidity and functional mobility in persons with Parkinson disease

Abstract

Objectives: To report the frequency, severity, and types of comorbidities in people with Parkinson disease (PD) using a validated self-report comorbidity screening tool, and to determine the relationship between comorbidity and functional mobility.

Design: A secondary analysis and cross-sectional observational study design.

Setting: University hospital; outpatient balance disorders laboratory.

Participants: Persons with mild to moderate idiopathic PD (N=76).

Intervention: Not applicable.

Main outcome measures: The Cumulative Illness Rating Scale-Geriatric (CIRS-G) and a comprehensive mobility assessment including gait (distance walked in 3 min), balance (mini-Balance Evaluation Systems Test), and physical function (Physical Performance Test).

Results: All participants reported comorbidities in addition to their diagnosed PD. The average ± SD number of comorbidities was 6.96 ± 2.0 (range, 2-11), and the total CIRS-G score ± SD was 12.7 ± 4.8. The most commonly reported organ systems with comorbidity were eyes and ears (89%), psychiatric (68%), musculoskeletal (64%), lower gastrointestinal (62%), respiratory (60.5%), upper gastrointestinal (59.2%), and genitourinary (53.9%). The total CIRS-G score was significantly related to functional mobility: gait (r=-.53, P=.0001), balance (r=-.43, P=.0003), and physical performance (r=-.36, P=.0041). Of the original 14 organ systems measured, there were 7 systems that, when combined, best predicted gait performance, 6 systems combined that best predicted balance performance, and 4 systems combined that predicted functional performance.

Conclusions: This study reports a high frequency of multiple medical system comorbidity in people with mild to moderate PD. Furthermore, comorbidity scores were associated with mobility disability: gait, balance, and physical function. Early intervention is important to delay mobility disability in PD, and we recommend that people with PD found to have comorbidities should be screened for balance and gait deficits.

Trial registration: ClinicalTrials.gov NCT01361724.

Keywords: Comorbidity; Parkinson disease; Postural balance; Rehabilitation.

Conflict of interest statement

OHSU and Dr. Horak have a significant financial interest in APDM, a company that may have a commercial interest in the results of this research and technology. This potential institutional and individual conflict has been reviewed and managed by OHSU.

Copyright © 2014 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

Figures

Figure 1

Average severity score (0–4) of each individual organ system. The dotted vertical line represents means for previously reported healthy normal subjects [10].