Age-specific progression of nigrostriatal dysfunction in Parkinson's disease.

OBJECTIVE: To investigate in vivo the impact of age on nigrostriatal dopamine dysfunction in Parkinson's disease (PD). METHODS: PD patients (n = 78) and healthy control subjects (n = 35) underwent longitudinal positron emission tomography assessments using 3 presynaptic dopamine markers: (1) [¹¹C](±)dihydrotetrabenazine (DTBZ), to estimate the density of the vesicular monoamine transporter type 2; (2) [¹¹C]d-threo-methylphenidate, to estimate the density of the plasma membrane dopamine transporter; and (3) 6-[¹8F]-fluoro-L-dopa, to estimate the activity of the enzyme dopa-decarboxylase. RESULTS: The study comprised 438 PD scans and 241 control scans (679 scans in total). At symptom onset, the loss of putamen DTBZ binding was substantially greater in younger compared to older PD patients (p = 0.015). Remarkably, however, the rate of progression of DTBZ binding loss was significantly slower in younger patients (p < 0.05). The estimated presymptomatic phase of the disease spanned more than 2 decades in younger patients, compared to 1 decade in older patients. INTERPRETATION: Our results suggest that, compared to older patients, younger PD patients progress more slowly and are able to endure more damage to the dopaminergic system before the first motor symptoms appear. These observations suggest that younger PD patients have more efficient compensatory mechanisms.

Acupuncture in the treatment of fatigue in Parkinson's disease: A pilot, randomized, controlled, study.

Introduction: Fatigue is a common and disabling problem in patients with Parkinson's disease (PD), and there is currently no satisfactory treatment. As acupuncture has been reported to be effective in fatigue related to other conditions, we sought to evaluate its efficacy in PD. Methods: This was a single center, randomized, sham-controlled study. Forty PD patients with moderately severe fatigue were randomized to receive 5 weeks of biweekly real or sham acupuncture. The primary outcome was change on the General Fatigue score of the Multidimensional Fatigue Inventory (MFI-GF) at 5 weeks. Secondary outcomes included MFI-Total score, Unified Parkinson's Disease Rating Scale Motor score (UPDRS Motor), Parkinson's Disease Questionnaire-39 (PDQ 39), Geriatrics Depression Scale (GDS), and Epworth Sleepiness Scale ESS). All outcome measures were evaluated at baseline, 5 and 9 weeks. Results: Both groups showed significant improvements in MFI-GF and MFI-Total scores at 5 and 9 weeks, but there were no significant between-group differences. There were no improvements from baseline for PDQ 39, GDS, and ESS. Although improvements were noted for the UPDRS Motor score in the real acupuncture group, no between-group difference could be demonstrated. Conclusions: Both real and sham acupuncture are equally effective in improving PD-related fatigue, and it is likely that this is due to nonspecific or placebo effects.