Rhinorrhea in Parkinson's disease: a consecutive multicenter study in Japan.

Recent reports suggest that rhinorrhea, defined as the presence of a runny nose unrelated to respiratory infections, allergies, or sinus problems, occurs more frequently among patients with Parkinson's disease (PD) than among healthy controls. We conducted a questionnaire survey in a multicenter study throughout Japan and compared the frequency of rhinorrhea between 231 PD and 187 normal control (NC) subjects. After excluding patients with rhinitis or paranasal sinusitis, a total of 159 PD and 59 NC subjects were included in our analysis. Rhinorrhea occurred more frequently in PD patients than NC subjects (33.3% vs. 11.9%; P=0.01). Among PD patients, rhinorrhea was more common in men than women (P=0.005). Rhinorrhea was not correlated with disease duration, modified Hoehn and Yahr score, disease type (akinesia rigidity vs. tremor dominant), or cardiac sympathetic function (evaluated by (123)I-metaiodobenzylguanidine uptake). To our knowledge, this is the first multicenter study on the frequency of PD-related rhinorrhea in Asian countries.