Subjective Vertical Position Allows Prediction of Postural Deterioration in Patients with Parkinson’s Disease

• Main Authors: Kyohei Mikami, Makoto Shiraishi, Tsutomu Kamo
• Format: Article
• Language: English
• Published: Hindawi Limited 2019-01-01
• Series: Parkinson's Disease
• Online Access: http://dx.doi.org/10.1155/2019/1875435
• ISSN: 2090-8083; 2042-0080

Background. We believe that, in patients with Parkinson’s disease (PD), a forward-directed increase in the subjective vertical position (SV) leads to prolonged worsening of forward flexion of the trunk (FFT) mainly because the body adjusts to the SV. We conducted a study to clarify the relation between the SV angle, FFT angle, and various other clinical measures by comparing baseline values against values obtained 1 year later. Methods. A total of 39 PD patients (mean age, 71.9 ± 10.1 years; disease duration, 7.2 ± 5.4 years; modified Hoehn & Yahr (mH&Y) score, 2.6 ± 0.7) were enrolled. The Unified Parkinson’s Disease Rating Scale score, Mini-Mental State Examination (MMSE) score, mH&Y score, FFT angle, SV angle, and levodopa-equivalent dose (LED) were assessed at the time of enrollment (baseline evaluation) and 1 year later. Results. Eighteen patients (46%) complied with the protocol and completed the study. Significant increases were observed in the 1-year SV angle (p=0.02), MMSE score (p=0.008), and LED (p=0.001) compared to baseline values. Correlation was observed between the baseline SV angle and baseline and 1-year FFT angles (r=0.64, p=0.008 and r=0.58, p=0.012, respectively) and between the 1-year SV angle and 1-year FFT angle (r=0.63, p=0.005). Conclusion. Our data suggest that the SV contributes to increased FFT.