Temperature sensation in Parkinson's disease measured by quantitative sensory testing: a single-center, case-control study.

BACKGROUND: The pathophysiology of abnormal temperature sensation in Parkinson's disease (PD) remains unclear. Abnormal thermal detection does not seem to depend on the dopaminergic deficit, suggesting that other systems play a role in these changes, probably both central and peripheral. METHODS: We measured thermal detection thresholds (TDT) using quantitative sensory testing (QST) in 28 patients with PD and compared them with 15 healthy controls. RESULTS: Of 28 patients, 21% had increased TDT according to the normative data. TDT were higher on the dominant side. No correlation between TDT and disease duration, severity of motor impairment, and dopaminergic therapy was observed. 50% of the patients had difficulty differentiating between warm and cold stimuli, as TDT were within the normal range in most of these patients. CONCLUSIONS: Twenty-one percent of the patients in our study had increased TDT according to the normative data. Abnormal thermal detection was more pronounced on the dominant side. Abnormal differentiation between the thermal stimuli suggest impaired central processing of thermal information.

Peripheral neuropathy in Parkinson's disease.

BACKGROUND: Recent studies suggest an increased frequency of peripheral neuropathy (PN) in Parkinson's disease patients (PD) (Toth et al. 2010). The aim of our study is to verify the increased frequency of PN in our group of PD patients compared to an age-matched control group. We sorted patients according to the duration of L-DOPA treatment, L-DOPA dosage, and age below or over 50 years. METHODS AND RESULTS: We conducted electromyography examinations (using conduction studies and needle electromyography) of 49 PD patients with asymptomatic polyneuropathy and 40 controls. Patients without risk factors for PN were included (fasting blood was analyzed to rule out possible causes of PN), as were relatively healthy controls without risk factors for PN. PN was defined using the American Academy of Neurology and Electrodiagnostic Medicine criteria (England et al. 2005). CONCLUSION: The frequency of polyneuropathy was significantly higher in PD patients than in controls (45% versus 2%, p<0.0001). We did not establish a relationship in the PD group according to long-term L-DOPA usage, PD duration, or age. It should be assumed that a neurodegenerative process underlies the involvement of the central and peripheral nervous systems in PD patients.

Premotor Parkinson's disease: Overview of clinical symptoms and current diagnostic methods.

Parkinson's disease (PD) is characterized by typical motor symptoms. However, recent studies show several non-motor features that may precede the development of the motor symptoms of PD. The best known premotor symptoms include hyposmia, REM sleep behavior disorder (RBD), constipation, and depression; other symptoms are excessive daytime somnolence, orthostatic hypotension and symptomatic hypotension, erectile or urinary dysfunction, musculoskeletal symptoms, pain, and global cognitive deficit. In this review, we summarize currently available diagnostic methods for these symptoms. We also briefly summarize neuroimaging, polyneuropathy, peripheral markers, and cerebrospinal fluid biomarkers that may be used in the early diagnosis of PD.