Non-motor off symptoms in Parkinson's disease

The aim of this study is to elucidate the clinical spectrum and frequency of non-motor symptoms during off periods (NMOS) in Parkinson's disease (PD) patients with motor fluctuation. We compared clinical characteristics between PD patients with motor symptoms only (M-off) and those with both motor and non-motor symptoms (NM-off) during off periods. The association of NMOS with parkinsonian clinical characteristics was also investigated. Sixty-seven consecutive PD patients of both M-off and NM-off groups were included in this study. We reviewed medical records, interviewed the patients, and administered a structured questionnaire. NMOS is classified into three categories: autonomic, neuropsychiatric and sensory. The frequency of NMOS and their individual manifestations were assessed. Of 67 patients with off symptoms, 20 were M-off group and 47 NM-off group. Among NMOS, diffuse pain was the most common manifestation, followed by anxiety and sweating. There were no significant differences between M-off and NM-off groups with regard to age, duration of disease and treatment, interval between onset of parkinsonian symptoms and off symptoms and off periods. Patients taking higher dosage of levodopa had fewer NMOS. NMOS is frequent in PD. Comprehensive recognition of NMOS can avoid unnecessary tests and is important for optimal treatment in PD.