Psychometric features of brief pain inventory for Parkinson's disease during medication states.

PURPOSE: Patients with idiopathic Parkinson's disease (PD) suffer from different non-motor symptoms, including pain. The present study aimed to measure the psychometric properties of the Brief Pain Inventory (BPI) in patients with PD during ON- and OFF-states. METHODS: We recruited 460 patients with PD and 100 non-PD controls. The pain was assessed by the BPI, King's Parkinson's disease Pain Scale (KPPS), Neuropathic Pain Symptom Inventory (NPSI), Visual Analogue Scale-Pain (VAS-pain), and short-form McGill Pain Questionnaire-2 (SF-MPQ-2) in both medication states. Internal consistency and test-retest reliability was examined using Cronbach's alpha coefficient and intra-class correlation coefficient (ICC). Dimensionality and convergent validity of BPI were also investigated. Diagnostic accuracy and discriminative validity were determined by Receiver Operating Characteristics (ROC) curve analysis and Area Under the Curve (AUC). RESULTS: Cronbach's alpha was satisfactory (α = 0.91-0.97) in both states. The ICC values were 0.85-0.96 in ON- and OFF-state. Factor analysis revealed two factors. A high correlation was obtained between BPI subscales and other scales. AUC >0.91, sensitivity, and specificity> 0.77 were observed for discriminating different pain levels. Furthermore, appropriate diagnostic accuracy was found (AUC, sensitivity, and specificity >0.67) between non-PD control and PD patients. CONCLUSION: The BPI has acceptable psychometric features as well as diagnostic accuracy for patients with PD.Implications for rehabilitationPain as a non-motor symptom in PD can affect daily and social activities.The BPI is used to assess pain severity and interference in activities.For better treatment, pain should be assessed in off-state like to on-state.BPI has satisfactory reliability and validity in different medication states in PD.

Anxiety and cognitive load affect upper limb motor control in Parkinson's disease during medication phases.

Anxiety is among the most debilitating nonmotor symptoms of Parkinson's disease (PD). This study aimed to determine how PD patients with low and high levels of anxiety (LA-PD and HA-PD, respectively) compare with age- and sex-matched controls at the level of motor control of reach-to-grasp movements during single- and dual-task conditions with varying complexity. Reach-to-grasp movement kinematics were assessed in 20 LA-PD, 20 HA-PD, and 20 sex- and age-matched healthy controls under single- as well as easy and difficult dual-task conditions. Assessment of PD patients was performed during both the on- and off-drug phases. The results obtained during dual-task conditions reveal deficits in both reach and grasp components for all three groups (e.g., decreased peak velocity and delayed maximum hand opening). However, these deficits were significantly greater in the PD groups, especially in the HA-PD group. Although dopaminergic medication improved reach kinematics, it had no effect on grasp kinematics. The results of our study indicated that high levels of anxiety may enhance the inefficiency of upper limb motor control in PD patients, especially during high demanding cognitive conditions, and should, therefore, be considered in the assessment and planning of interventions for upper limb function in these patients.

A simple method for determination of D-penicillamine on the carbon paste electrode using cupric ions.

The interaction of D-penicillamine (PA) with copper at the carbon paste electrode (CPE) in the presence of cupric ions (Cu(2+)) was used for the determination of PA at very low potential (0.1 V vs. Ag/AgCl) without applying of any modifier. The electrochemical response of copper is changed considerably in the presence of negligible amount of PA. In this report some important parameters, such as pH effect, Cu(2+) concentration and scan rate are studied, which the selected conditions were acetate buffer (pH=6) and 1 mM Cu(2+). The linear range for PA was from 1.0×10(-6) to 1.0×10(-4) M with an experimental detection limit of 1.0×10(-7) M. The relative standard deviation for 6 measurements was 3.8%. The interfering effects of some important inorganic ions were investigated, which there was no significant effect on the PA measurements. Also three organic interferences including ascorbic acid (AA), uric acid (UA) and l-cysteine (Cys) were examined, which the effect of AA was not notable, the interference of UA was moderate and for Cys was significant, but moderate at the levels which fined in the urine samples. This method was applied successfully for the determination of PA in urine sample.