Tasks of attention augment rigidity in mild Parkinson disease.

OBJECTIVE: The purpose of this study was to determine whether tasks involving effortful attention would cause augmentation of rigidity in patients with mild Parkinson disease. METHODS: In 17 subjects with mild Parkinson disease, rigidity in a single arm was assessed during various experimental conditions by a blinded movement disorders neurologist. Rigidity was scored separately at the wrist and the elbow using an ordinal scale. In three of the conditions, sustained attention was directed toward visual, auditory or movement-related stimuli. Two varieties of Froment maneuver served as positive controls: contralateral hand opening-closing or ipsilateral foot tapping. In addition, rigidity was assessed twice with subjects resting. The examiner was unaware of the sequence of experimental conditions and this was changed for each subject. Mean rigidity scores for the various experimental conditions were compared against the baseline state (an average of both trials with the patient resting) using a repeated measures ANOVA and post-hoc Tukey-Kramer multiple comparisons test. RESULTS: Rigidity was significantly increased from baseline with each of the attentional tasks (p < 0.01 to p < 0.001) and also with the two Froment maneuvers (p < 0.001). Rigidity augmentation with contralateral hand opening-closing was significantly greater than with any of the attentional tasks (p < 0.05 to p < 0.001). CONCLUSION: Tasks of effortful attention did appear to augment rigidity in patients with mild Parkinson disease. We speculate that the greater augmentation seen with the Froment maneuver could have an anatomic basis.

Methylphenidate improves fatigue scores in Parkinson disease: a randomized controlled trial.

Fatigue is a common nonmotor symptom in idiopathic Parkinson disease (IPD) that can prominently affect everyday function. This study was a randomized, double-blind, placebo-controlled trial evaluating methylphenidate for the treatment of fatigue in patients with IPD maintained on their regular medications. Thirty-six patients were randomized to receive either methylphenidate (10 mg three times per day; n = 17) or placebo (n = 19) for 6 weeks. Primary outcomes were the change from baseline on two separate self-report fatigue questionnaires: the Fatigue Severity Scale (FSS) and the Multidimensional Fatigue Inventory (MFI). Secondary outcomes included the Unified Parkinson Disease Rating Scale (UPDRS) motor score and the five individual domains of the MFI. Fourteen patients in the methylphenidate group and 16 patients in the control group remained on the intervention for the entire study period. In the treatment arm, mean FSS score was reduced by 6.5 points (from a baseline of 43.8) and mean MFI score was reduced by 8.4 points (from a baseline of 51.0). Both these reductions were significant (P < 0.04). Smaller reductions in the placebo group were nonsignificant. Mean UPDRS motor score did not change significantly in either group. Analysis of MFI subscores showed a significant reduction in General Fatigue in the methylphenidate group (P < 0.001). Overall, adverse effects of medication were more frequent in the placebo group. In conclusion, methylphenidate was effective in lowering fatigue scores in patients with IPD following a 6-week treatment period.