Clinical idiopathic Parkinson's disease (PD) diagnosis requires following strict clinical criteria. Final definitive diagnosis can only be made after pathological confirmation and, despite following clinical criteria, several cases are misdiagnosed. We assessed sensitivity and specificity of acute challenge with levodopa (L-dopa) to predict sustained long-term L-dopa responsiveness as a major criterion for clinical diagnosis of PD. A consecutive series of 82 patients first seen at a movement disorders clinic with a parkinsonian syndrome without specific diagnosis was included. A second examiner, blind to the presumptive diagnosis, performed in each patient an acute challenge with 250/50 mg of L-dopa-carbidopa and rated the test as positive or negative according to whether values reached a minimal 30% of improvement on UPDRS scores. Positive tests were considered supportive of presumptive clinical diagnosis of Parkinson's disease. Blind to test results and according to clinical presumption, the first examiner started patient treatment with the necessary L-dopa dose or, alternatively, until reaching 1 g for 1 month in those who failed to display a positive test response. At 24 month follow-up, they were re-tested with 1 g for 1 month when required. At this point, clinical criteria of the U.K. Parkinson's Disease Society Brain Bank were applied and definitive clinical diagnosis of PD was made. Sensitivity, specificity, and positive predictive ratio for acute challenge were calculated. Overall sensitivity and specificity of acute L-dopa challenge to predict clinical diagnosis of PD was 70.9% and 81.4%, respectively; positive predictive ratio was 88.6%. When patients were divided into three groups according to their UPDRS motor section score at initial examination, sensitivity and specificity varied: Group I (or=21), 36.4% and 87%, respectively. Positive predictive ratio increased to 100% in Group I and to 87.5% in Group III. The positive result of initial acute L-dopa challenge predicts chronic L-dopa responsiveness as major criterion of PD in all patients with UPDRS motor scores lower than 10.
Sialorrhea is common in Parkinson disease (PD), affecting approximately 70% to 75% of patients. Several tools for measuring saliva volume or production exist, but none are designed specifically for assessing sialorrhea-related discomfort. The objective of this study was to develop and validate a clinical scale for subjective evaluation of sialorrhea in PD. In Phase I, internal consistency of the Sialorrhea Clinical Scale for PD (SCS-PD) was established in 39 PD patients. In Phase II, scale validity was proven through saliva volume measurements obtained in 49 PD patients and 27 healthy volunteers. Internal consistency estimated using Cronbach's alpha was 0.78, indicating none of the original seven items tested needed to be removed. Twenty-one patients complaining of sialorrhea (63%) studied during Phase II, showed higher SCS-PD scores but no differences in saliva volume. SCS-PD scores showed significant correlation with saliva volume (r = 0.41; P = 0.004) and with total Unified Parkinson's Disease Rating Scale Part III (UPDRS III) scores (r = 0.70). Furthermore, saliva volume showed inverse relation to age in PD patients as well as in controls (r = -0.3 and r = -0.4; P < 0.05), but SCS-PD scores did not. The SCS-PD scale showed good internal consistency and validity, providing support for its use in routine clinical sialorrhea-related discomfort evaluation.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.