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Is the MDS-UPDRS a Good Screening Tool for Detecting Sleep Problems and Daytime Sleepiness in Parkinson’s Disease?

Movement Disorder Society-sponsored Unified Parkinsons Disease Rating Scale (MDS-UPDRS) has separate items for measuring sleep problems (item 1.7) and daytime sleepiness (1.8). The aim of our study was to evaluate the screening sensitivity and specificity of these items to the PD Sleep Scale 2nd version (PDSS-2) and Epworth Sleepiness Scale (ESS). In this nationwide, cross-sectional study 460 PD patients were enrolled. Spearmans rank correlation coefficients were calculated between the individual items, domains, and the total score of PDSS-2 and item 1.7 of MDS-UPDRS. Similarly, the items and the total score of ESS were contrasted to item 1.8 of MDS-UPDRS. After developing generalized ordinal logistic regression models, the transformed and observed scores were compared by Lins Concordance Correlation Coefficient. Only item 3 difficulties staying asleep and the “disturbed sleep” domain of PDSS-2 showed high correlation with “sleep problems” item 1.7 of the MDS-UPDRS. Total score of PDSS-2 had moderate correlation with this MDS-UPRDS item. The total score of ESS showed the strongest, but still moderate, correlation with “daytime sleepiness” item 1.8 of MDS-UPDRS. As intended, the MDS-UPDRS serves as an effective screening tool for both sleep problems and daytime sleepiness and identifies subjects whose disabilities need further investigation.

No correlation between impairment of cerebrovascular reserve capacity and electrophysiologically assessed severity of neuropathy in noninsulin-dependent diabetes mellitus.

INTRODUCTION Microvascular abnormalities have an important role in the most frequent neurological complications of diabetes mellitus: neuropathy and cerebrovascular disorders. Severity of neuropathy as well as of cerebral microvascular damage can be quantitatively evaluated by instrumental methods like nerve conduction studies and transcranial Doppler. In the present study, we investigated whether a correlation exists between the severity of peripheral neuropathy and the impairment of cerebrovascular reserve capacity (CRC) in 20 patients with Type 2 diabetes mellitus. METHODS CRC was measured by transcranial Doppler and defined as the maximal percentage increase in blood flow velocity in the middle cerebral artery within 20 min after an intravenous dose of 1000 mg of acetazolamide. Nerve conduction studies of the median, ulnar, peroneal, and sural nerves were performed. Severity of neuropathy was scored based on conduction velocities, amplitudes, and distal latencies. RESULTS There was no correlation between the neuropathic score and CRC (R= .003, P= .99). Neither CRC nor the neuropathic score correlated significantly with age, duration of diabetes, and serum values of HbA(1c), glucose, insulin, von Willebrand factor, and alpha(2) - macroglobulin. Severity of neuropathy but not CRC correlated with microalbuminuria (R= .47, P= .038 and R= .14, P= .54). Improper treatment reflected by HbA(1c) >10% was associated with significantly more severe albuminuria, higher actual blood glucose level, higher von Willebrand factor activity, and marginally higher neuropathic score (21 vs. 13, P=.096), but was not associated with CRC (44% vs. 42%, P= .81). When duration of diabetes was dichotomized to 15 years and less or over 15 years, CRC was significantly smaller (35% vs. 50%, P= .036) and neuropathy was more severe in the subgroup with longer diabetes duration (19 vs. 11.5 points, P= .07). CONCLUSIONS Although both CRC and peripheral nerve function are affected more severely in patients with long-lasting Type 2 diabetes mellitus, damage in the cerebrovascular system and in the long peripheral nerves occur independently. As in diabetes mellitus pathological changes in autonomic and large peripheral nerves develop simultaneously, decreased CRC in diabetic patients might be predominantly due to structural changes of resistance arteries or to metabolic than to neurogenic factors.

Peripheral nerves are progressively involved in multiple sclerosis – A hypothesis from a pilot study of temperature sensitized electroneurographic screening

Multiple sclerosis (MS) is primarily a disease of the central nervous system. Although the involvement of the peripheral nervous system in MS was suggested over 100 years ago, the issue is still controversial, and it is generally accepted that except for the optic nerve the peripheral nerves are left unaffected by the disease. We hypothesize, that an electroneurographical study if thorough enough, may reveal differences in some nerve conduction parameters between MS patients and healthy subjects. Second, we assume that the sensitivity of nerve conduction measurements might be increased if performed at a range of temperatures, reflecting a differential effect of cooling and warming on the peripheral nerve conduction parameters in MS patients and controls. Finally, we expect that the differences in these parameters between controls and MS patients will increase with the progression of the disease. To test these hypotheses in a pilot study, we performed a detailed analysis of the motor and sensory nerve conduction features of the right median nerve in 13 MS patients and 13 controls at 5 degrees C increments between 20 and 40 degrees C, and repeated these measurements after 3 years. The motor latencies were 0.3-0.6 ms longer in MS patients compared to the controls both initially and 3 years later (0.058<p<0.09). The durations and areas of the compound motor action potential (CMAP) appeared more sensitive to changes in temperature in the MS group (0.057<p<0.1). The change in both distal motor latency and sensory latency per unit change in temperature decreased significantly in 3 years within the MS but not in the control group. These results suggest a mild and progressive involvement of the PNS in MS. Most differences in this pilot study were on the border of statistical significance therefore our hypotheses should be confirmed in studies with larger sample size.

Effect of subthalamic stimulation on distal and proximal upper limb movements in Parkinson's disease

INTRODUCTION A different innervation pattern of proximal and distal muscles from the contra- and ipsilateral motor circuits raises the question as to whether bilateral, contra- and ipsilateral subthalamic stimulation may have different effects on the distal and proximal movements of the upper limb. To answer this question, we performed kinematic analyzes in patients with Parkinsons disease. METHODS Twenty-eight Parkinsonian patients treated by bilateral subthalamic stimulation were examined with an age-matched control group of 28 healthy subjects. They performed 14s of finger tapping, hand grasping and pronation-supination. The patient group performed these sessions in four conditions (BOTH ON, BOTH OFF, CONTRA ON, IPSI ON) after withdrawal of dopaminergic medication for 12h and a fifth condition after taking medication (BOTH ON-MED ON). A motion sensor with a three-dimensional gyroscope was worn on the index finger. Speed, amplitude, rhythm and decrement of movements were calculated and compared across these conditions. RESULTS Speed and amplitude of the more distal movements were improved similarly by contra- and bilateral stimulation. Bilateral stimulation was more effective than contralateral stimulation for the more proximal movements. Contra- and bilateral stimulation ameliorated the rhythm similarly in each movement task. Decrement of distal and proximal movements was not affected by the stimulation conditions. CONCLUSION This is the first study to show that the outcome of bi- and unilateral subthalamic stimulation on proximal and distal upper limb movements should be evaluated separately postulating the different somatotopic organization of subloops in the cortico-basal ganglia motor circuits.