Affiliations: [a]
Department of Neurology, Yonsei University College of Medicine, Seoul, South Korea
| [b]
Department of Neurology, Sanggye Paik Hospital, Inje University College of Medicine, Seoul, South Korea
| [c]
Department of Neurology, Yongin Severance Hospital, Yonsei University Health System, Yongin, South Korea
| [d]
Department of Neurology, Busan Paik Hospital, Inje University College of Medicine, Seoul, South Korea
| [e]
Severance Biomedical Science Institute, Yonsei University College of Medicine, Seoul, South Korea
Correspondence:
[*]
Correspondence to: Phil Hyu Lee, MD, PhD, Professor, Department of Neurology, Yonsei University Medical College, 50 Yonsei-ro, Seodaemun-gu, Seoul, 03722, South Korea. Tel.: +82 2 2228 1608; Fax: +82 2 393 0705; E-mail: phlee@yuhs.ac.
Abstract: Background:Neuropsychiatric symptoms (NPS) are the most common non-motor symptom in Parkinson’s disease (PD). Objective:To investigate the association between the burden of NPS and motor prognosis in patients with PD. Methods:We enrolled 329 drug-naïve patients with PD, who was non-demented and followed-up≥2 years after their first visit to the clinic with baseline dopamine transporter (DAT) imaging and neuropsychiatric inventory (NPI) scores. We performed a survival analysis and a linear mixed model analysis to assess longitudinal motor outcomes according to the NPI total score. Results:The Kaplan-Meier analysis showed no difference in the development of levodopa-induced dyskinesia and wearing-off according to the NPI total score. However, higher burden of NPI total score was associated with earlier freezing of gait (FOG) development in the time-dependent Cox regression models after adjusting for age at symptom onset, sex, disease duration, Unified PD Rating Scale motor score, baseline Mini-Mental State Examination score, DAT activity in the posterior putamen and levodopa-equivalent daily dose (LEDD) (Hazard ratio 1.047, p = 0.002). A linear mixed model analysis revealed that patients with a higher NPI total score had a more rapid LEDD increment (NPI×time, p = 0.003). Among 52 patients with PD who eventually developed FOG during the follow-up period, there was a significant correlation between the NPI total score and time with FOG development (γ= –0.472; p = 0.001) after adjusting for confounding factors. Conclusion:The present study demonstrated that the severity of NPS is a predictor of early freezing and motor progression in patients with PD.
Keywords: Parkinson’s disease, neuropsychiatric symptoms, motor prognosis
