title: Nonmotor predictors for levodopa requirement in de novo patients with Parkinson's disease.
abstract: The variability in the clinical phenotype of Parkinson's disease (PD) suggests the existence of several subtypes of the disease. Motor heterogeneity of PD is well established, but not nonmotor heterogeneity. At present, we are unable to predict the rate of progression of PD based on robust biomarkers. We aimed to examine the heterogeneity of PD by attempting to identify nonmotor factors associated with the rate of motor progression and functional decline, as measured by the time to reach the need for levodopa therapy during the first 4 years from diagnosis in a cohort of de novo PD patients. The median time to introduction of L-dopa for patients with urinary symptoms was significantly shorter than that for those without (20 vs. 37 months; P = 0.001). Cox's regression models showed that the urinary domain was associated with a higher probability of starting L-dopa (hazard ratio: 2.1; P = 0.002). There was no influence of such confounders as sex, age, baseline motor features, use of dopamine agonists and/or monoamine oxidase B inhibitors, and total L-dopa equivalent daily dosage. Patients with urinary symptoms had higher baseline and follow-up motor and nonmotor disturbances than those without. Our study suggests the existence of a subgroup of patients who show urinary symptoms along with an overall higher motor and nonmotor burden. Such patients are prone to manifest a rapid functional decline over the first 4 years of the disease. Urinary symptoms might be a clinical marker of severity as well as a possible nonmotor subtype of PD.
authors: Sobell Department of Motor Neuroscience and Movement Disorders, University College London (UCL) Institute of Neurology, London, United Kingdom; Dipartimento di Scienze Neurologiche e del Movimento, Università di Verona, Policlinico Borgo Roma, Verona, Italy.
authors: Roberto
authors: R
authors: Erro
authors: Marina
authors: M
authors: Picillo
authors: Marianna
authors: M
authors: Amboni
authors: Marcello
authors: M
authors: Moccia
authors: Carmine
authors: C
authors: Vitale
authors: Katia
authors: K
authors: Longo
authors: Maria Teresa
authors: MT
authors: Pellecchia
authors: Gabriella
authors: G
authors: Santangelo
authors: Pablo
authors: P
authors: Martinez-Martin
authors: K Ray
authors: KR
authors: Chaudhuri
authors: Paolo
authors: P
authors: Barone
mesh_terms: D000368:Aged; D000978:Antiparkinson Agents / Q000009:adverse effects*; D015331:Cohort Studies; D005260:Female; D006801:Humans; D007980:Levodopa / Q000009:adverse effects*; D008297:Male; D008875:Middle Aged; D008996:Monoamine Oxidase Inhibitors / Q000627:therapeutic use*; D010300:Parkinson Disease / Q000188:drug therapy*; D011237:Predictive Value of Tests; D012720:Severity of Illness Index; D014570:Urologic Diseases / Q000139:chemically induced*
chemical_list: D000978:Antiparkinson Agents; D008996:Monoamine Oxidase Inhibitors; D007980:Levodopa
keywords: PD subtypes; de novo; early Parkinson's disease; newly diagnosed; nonmotor symptoms; progression