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Objectives To explore the impact of sex and age on relationship between prodromal constipation and disease phenotype in Parkinson’s disease at early stages. Methods A total of 385 Parkinson’s disease patients from the PRIAMO study were classified according to the presence of prodromal constipation and followed for 24 months. Multivariable mixed-effect models were applied. All analyses were performed separately for sex (64.1% men) and median age (different by sex: 67 years-old in men and 68 years-old in women). Results As for sex, prodromal constipation was associated with greater odds of attention/memory complaints and apathy symptoms in women only. As for age, prodromal constipation was associated with lower cognitive and higher apathy scores in older patients only. Conclusions Prodromal constipation anticipates lower cognitive performances and more severe apathy since the earliest stages in women and older patients. Sex- and age-related heterogeneity of prodromal markers of Parkinson’s disease may impact disease phenotype.

Background Parkinson's Disease-related Psychosis (PDP) encompasses a spectrum of symptoms ranging from “minor” hallucinations to formed hallucinations and delusions. Notably, cognitive impairment has been recognized as the strongest risk factor for PDP. Several evidences suggest a possible role of cigarette smoking in both cognition and psychotic syndromes. Objectives To evaluate the possible independent association between cigarette smoking and PDP in a large cohort of non-demented PD patients. Methods A cohort of non-demented PD patients was selected from the FRAGAMP study population. All participants underwent a standardised structured questionnaire to assess demographic, clinical and environmental exposure data. Clinical features were assessed using UPDRS, HY stage, AIMS, MMSE and Hamilton Rating Scale for Depression. Presence of psychotic symptoms was assessed using UPDRS-I.2 score. Diagnosis of PDP was made according to NINDS/NIMH criteria. Results Four hundred eighty-five non-demented PD patients were enrolled [292 men (60.2%); mean age ± SD 65.6 ± 9.8]. Among them, 28 (5.8%) had PDP. Multivariate analysis, adjusting by HY stage, MMSE and LED, shown an independent association between PDP and “nightmares-abnormal movements during sleep” and current smoking [adjOR 7.39 (95%CI 1.45–37.69; P-value 0.016)]. Conclusions Our findings provide interesting insights about the possible role of current smoking in facilitating the occurrence of psychotic symptoms in PD.

It is unclear whether patients with different clinical phenotypes of Parkinson's disease (PD) differ in their risk of developing levodopa-induced dyskinesia. We evaluated the possible association between clinical phenotypes and risk of levodopa-induced dyskinesia in PD patients using a case-control design. The FRAGAMP study is a large Italian multicenter study. Patients affected by PD diagnosed according to the Gelb's criteria were enrolled and underwent a face-to-face interview. Clinical scales were used to evaluate motor and cognitive impairment. Presence of dyskinesia was assessed by the item 32 of the UPDRS section IV. On the basis of the most prominent motor symptoms at onset PD, patients were classified as tremor-dominant, akinetic-rigid, or mixed type. 485 PD patients (292 men; mean age 65.6 ± 9.8) were enrolled in the study of whom 128 (26.4 %) presented levodopa-induced dyskinesia. Of the 485 patients, 311 (64.1 %) were classified as tremor-dominant, 104 (21.4 %) as Akinetic-Rigid and 70 (14.4 %) as mixed type. Multivariate logistic regression analysis showed a significant negative association between tremor-dominant phenotype and levodopa-induced dyskinesia (adjusted OR 0.48; 95 % CI 0.23-1.00; p value 0.05). When analysis was stratified by age at onset a stronger negative association was found among the late onset (>50 years) PD patients (OR 0.28; 95 % CI 0.11-0.70; p value 0.007) while no association was found among patients with an early onset. Our findings support the hypothesis that the occurrence of resting tremor as an initial manifestation of PD may predict a lower probability of developing levodopa-induced dyskinesia.

Background and purpose New venues are currently being explored to predict disease progression in Parkinson's disease (PD), such as non-motor subtypes and models merging motor and non-motor symptoms (NMS). By involving a subgroup of 585 patients from the PRIAMO (Parkinson Disease Non-motor Symptoms) study, the present 24-month longitudinal prospective analysis aimed to demonstrate that urinary dysfunction is an early marker of higher motor and non-motor burden as well as lower health-related quality of life. Methods and results Multivariable mixed-effect logistic regression models controlling for demographic and clinical variables showed that the following NMS domains were associated with urinary dysfunction: gastrointestinal [odds ratio (OR) 2.57, 95% confidence interval (CI) 1.67–3.97, P < 0.001], cardiovascular (OR 2.22, 95% CI 1.18–4.17, P = 0.013), skin (OR 1.81, 95% CI 1.06–3.08, P = 0.029), sleep (OR 2.06, 95% CI 1.34–3.16, P = 0.001), pain (OR 1.85, 95% CI 1.21–2.83, P = 0.004), fatigue (OR 2.40, 95% CI 1.56–3.68, P < 0.001), apathy (OR 2.79, 95% CI 1.72–4.52, P < 0.001) and respiratory (OR 1.82, 95% CI 1.02–3.23, P = 0.039). Analysis also demonstrated that urinary dysfunction was associated with higher motor disability (coefficient 1.73, 95% CI 0.68–2.78, P = 0.001) and lower health-related quality of life (coefficient −0.05, 95% CI −0.08 to −0.02, P < 0.001, and coefficient −3.49, 95% CI −5.21 to −1.77, P < 0.001) but not with more severe cognitive disability (coefficient −0.34, 95% CI −0.92 to 0.24, P = 0.251). Conclusions This is the first prospective longitudinal study involving a large cohort of PD patients demonstrating the relevance of urinary dysfunction as an early marker of higher motor and non-motor disability as well as lower health-related quality of life. These findings support a role for urinary dysfunction as an early marker of more severe disease progression.

We evaluated the possible association between head trauma and Parkinson's disease (PD). The FRAGAMP (Fattori di Rischio Ambientali e Genetici Associati alla Malattia di Parkinson) study is a large Italian multicenter case-control study carried out to evaluate the possible role of environmental and genetic factors in PD. Cases and controls were enrolled from six movement disorders centers located in the Central-Southern Italy. A standardized questionnaire was administered to record demographic, epidemiological, and clinical data. Positive history of head trauma was considered only if the head trauma preceded the onset of PD. All cases and controls underwent a standard neurological examination. Adjusted ORs and 95% CI were estimated using multivariate analysis (logistic regression). Four hundred ninety-two PD patients (292 men and 200 women) and 459 controls (160 men and 299 women) were enrolled in the study. A positive history for head trauma was reported by 106 (21.5%) PD patients and by 62 (13.5%) healthy controls. Multivariate analysis (OR adjusted by age, sex, family history, coffee smoking, and alcohol consumption) showed a significant positive association between PD and head trauma with an adjusted OR of 1.50 (95%CI 1.04-2.17; p value 0.03). In agreement with literature data, our study supports the positive association between head trauma and PD.

Background: The objective of this study was to evaluate the possible association between endogenous and exogenous estrogens and Parkinson's disease (PD). Methods: The FRAGAMP study is a large Italian multicenter case–control study. PD was diagnosed according to Gelb's criteria. A standardized questionnaire was administered to record demographic, epidemiological, and clinical data. Adjusted ORs and 95% CIs were estimated using multivariate analysis (logistic regression). Results: Two hundred PD women (mean age, 68.0 ± 9.5 years) and 299 control women (mean age, 61.8 ± 9.9 years) were enrolled in the study. Age at menarche, age at menopause, fertile life duration, cumulative duration of pregnancies, hormone replacement therapy, and surgical menopause were not significantly associated with PD. Multivariate analysis showed a significant positive association between use of oral contraceptives and PD, with an adjusted OR of 3.27 (95% CI, 1.24–8.59; P = .01). Conclusions: Our data suggest that oral contraceptives could increase the risk of PD. © 2011 Movement Disorder Society

The purpose of this study was to evaluate the possible association of cigarette smoking, coffee drinking, and wine consumption with essential tremor using a matched case-control design. Cases and controls were enrolled from 6 Movement Disorder centers in central-southern Italy. Essential tremor was diagnosed according to Bain's criteria. Three unrelated healthy controls (not affected by neurological disorders) per each enrolled case, matched by sex and age (± 5 years), were selected. A standardized questionnaire was administered to record demographic, epidemiological, and clinical data. All cases and controls underwent a standard neurological examination. Adjusted odds ratios and 95% confidence intervals were estimated using conditional logistic regression for the matched cases and controls. Eighty-three patients with essential tremor (38 men and 45 women; mean age, 68.2 ± 8.6 years) and 245 matched control subjects (113 men and 132 women; mean age, 68.4 ± 9.7 years) were enrolled in the study. Multivariate analysis showed a significant negative association between essential tremor and wine consumption preceding the onset of disease (adjusted odds ratio, 0.23; 95% confidence interval, 0.08-0.64; P = .0005) with a significant dose effect (1-2 glass of wine per day: odds ratio, 0.32; 95% confidence interval, 0.10-0.95; P = .04; more than 3 glass of wine per day: odds ratio, 0.14; 95% confidence interval, 0.03-0.62; P = .01). In our sample no association between essential tremor and cigarette smoking or coffee drinking was found. Our data suggest a negative association between wine drinking and essential tremor, which could be explained by the long-term neuroprotective effect of its antioxidant components.

Clinical distinction between Lewy bodies disease (LBD) and frontotemporal dementia (FTD) is sometimes difficult. Nigrostriatal dopaminergic degeneration occurs in both LBD and FTD, limiting helpfulness of DAT imaging to differentiate these forms of dementia. Several studies have emphasized the usefulness of myocardial scintigraphy with 123 Metaiodobenzylguanidine ( 123 I-MIGB) in assessing the sympathetic nerve terminals in LBD demonstrating that cardiac 123 I-MIGB uptake is decreased in patients with this disease. We investigated the role of cardiac 123 I-MIBG scintigraphy in differentiating patients with LBD from those with FTD. Clinical diagnosis of LBD and FTD was determined according to established consensus criteria. Nine patients with LBD (1 possible and 8 probable), 6 patients with FTD, and 16 control subjects were involved in the study. The heart to mediastinum ratio (H/M) of 123 I-MIBG uptake was markedly reduced in all patients with LBD (H/M early: 1.25 ± 0.12; delayed: 1.14 ± 0.13) whereas it was normal in patients with FTD (H/M early: 1.86 ± 0.20; delayed: 1.80 ± 0.23) and in controls (H/M early: 1.91 ± 0.17; delayed: 1.99 ± 0.19), suggesting that cardiac 123 I-MIBG scintigraphy can help distinguish patients with LBD from those with FTD.

The Fattori di Rischio Ambientali e Genetici Associati alla Malattia di Parkinson (FRAGAMP) study is a multicenter case-control study carried out to evaluate the possible role of environmental and genetic factors in Parkinson's disease (PD). Cases and controls were enrolled from five Movement Disorder centers in Central-Southern Italy. PD was diagnosed according to Gelb's criteria while the control groups consisted of the spouses of the enrolled patients or of healthy controls matched by age and area of residence. Cases and controls underwent a standardised questionnaire and a blood sample was taken for molecular analyses. At the end of the study 585 cases and 481 control subjects (287 spouse-controls and 194 generic-controls) were enrolled. Patients had a Hoehn-Yahr score of 2.3 +/- 0.8; 85% of them took levodopa and 47% had motor complications. The FRAGAMP study represents one of the largest case-control studies carried out in Europe to investigate the possible role of environmental and genetic factors in PD.

Freezing of gait (FOG) generally occurs as a late manifestation of Parkinson's Disease (PD). FOG, however, can present in isolation, constituting the so-called "Primary Progressive Freezing Gait"(PPFG). Myocardial (123)Metaiodiobenzylguanidine (MIBG) enables the assessment of postganglionic sympathetic cardiac nerve terminals. MIBG uptake reflects sympathetic system integrity, and reduced myocardial uptake of the tracer has been observed in nearly all patients with PD. We investigated MIBG uptake in 7 patients with PPFG, 14 patients with mild PD, and 6 patients with advanced PD and FOG (PD-FOG), and 18 control subjects. Our study shows that myocardial MIBG uptake was normal in all patients with PPFG (H/M ratio: mean+/-SD, 1.85+/-0.11 early; 1.71+/-0.15 delayed) and in the controls (H/M ratio: mean+/-SD, 1.94+/-0.18 early; 2.02+/-0.19 delayed) whereas it was markedly decreased in the patients with mild and advanced PD (H/M ratio: mean+/-SD, PD: 1.17+/-0.02 early; 1.16+/-0.02 delayed; PD-FOG: 1.22+/-0.10 early; 1.08+/-0.06 delayed). Our findings demonstrate that cardiac sympathetic denervation did not occur in patients with PPFG, confirming that PPFG and PD are distinct diseases.

The early diagnosis of progressive supranuclear palsy (PSP) may be challenging, because of clinical overlapping features with Parkinson's disease (PD) and other parkinsonian syndromes such as the Parkinsonian variant of multiple system atrophy (MSA-P). Conventional MRI can help in differentiating parkinsonian disorders but its diagnostic accuracy is still unsatisfactory. On the basis of the pathological demonstration of superior cerebellar peduncle (SCP) atrophy in patients with PSP, we assessed the SCP apparent diffusion coefficient (ADC) values in patients with PSP, PD, and MSA-P in order to evaluate its differential diagnostic value in vivo. Twenty-eight patients with PSP (14 with possible-PSP and 14 with probable-PSP), 15 PD, 15 MSA-P, and 16 healthy subjects were studied by using diffusion weighted imaging (DWI). ADC was calculated in regions of interest defined in the left and right SCP by two clinically blinded operators. Intrarater (r = 0.98, P < 0.001) and interrater reliability (r = 0.97; P < 0.001) for SCP measurements were high. Patients with PSP had higher SCP rADC values (median 0.98 × 10−3mm2/s) than patients with PD (median 0.79 × 10−3 mm2/s, P < 0.001), MSA-P (median 0.79 × 10−3 mm2/s, P < 0.001), and healthy controls (median 0.80 × 10−3 mm2/s, P < 0.001). DWI discriminated patients with PSP from PD and healthy subjects on the basis of SCP rADC individual values (100% sensitivity and specificity) and from patients with MSA-P (96.4% sensitivity and 93.3% specificity). The higher values of rADC in SCP of patients with PSP correspond with the in vivo microstructural feature of atrophy detected postmortem and provide an additional support for early discrimination between PSP and other neurodegenerative parkinsonisms. © 2008 Movement Disorder Society

Aim of this study was to evaluate prevalence of use and prescribing pattern of Anti-Parkinson Drugs (APDs) in general practice of Southern Italy. Among 120,000 individuals registered in the lists of 93 general practitioners of Southern Italy, we estimated one-year prevalence and incidence of APD use in the years 2003–2005. Overall, prevalence of APD use remained stable over the years and it strongly increased in subjects over 70 years of age. L-Dopa with a dopa decarboxylase inhibitor was the most frequently prescribed APD, although the use of both ergot and non-ergot derivative DAs has increased, particularly, in the elderly. A high proportion of APD users (15–20%) received only one prescription during the study period.

The arginine growth hormone (GH) stimulation test differentiates the Parkinsonian variant of multiple system atrophy (MSA-P) from idiopathic Parkinson's disease (PD). Our aim was to evaluate the accuracy of the arginine GH stimulation test in distinguishing between PSP, MSA-P, and PD. We measured the GH response to arginine in serum samples of 26 MSA-P, 23 PSP, and 26 PD patients, and in 80 healthy controls. We used ANOVA followed by the Bonferroni test to compare GH values and peaks among groups. We used receiver operating characteristic curve analysis to establish the arginine cut-off level that best differentiated between MSA-P, PSP, and PD. The GH peak was significantly lower (P < 0.01) in MSA-P (1.46 ± 0.29 μg/L) than in both PD (8.74 ± 0.98 μg/L) and PSP (6.64 ± 0.82 μg/L) patients, and controls (8.59 ± 0.44 μg/L). Growth hormone peaked later in PSP patients than in PD patients and controls. At a cut-off level of 4 μg/L, arginine test distinguished MSA-P from PD with a sensitivity of 92% and a specificity of 96%, and MSA-P from PSP with a sensitivity of 78% and a specificity of 96%. The GH response to arginine differentiates MSA-P from PD and PSP with a good diagnostic accuracy. The neuroendocrine response to arginine of PSP patients differed from that of MSA-P patients, but was not identical to that of normal controls and PD patients. Our results suggest that the impairment of the central mechanisms modulating GH release differs between PSP and MSA-P. © 2007 Movement Disorder Society

Aim of this study was to investigate the relationship between height in young adult age and Parkinson's disease (PD) risk. We included 266 persons affected by idiopathic PD. Patients were matched by age and sex to 266 controls by a random selection from the municipality of residence. We collected information about height preceding PD from official documents where these characteristics referred to young adult age (nearly 30 years). We compared height in cases and controls by calculating differences in mean distribution and by χ2 analyses. Crude and adjusted odds ratios (OR) and 95% confidence intervals (CI) were calculated by logistic regression models. Mean height was significantly lower in persons affected by PD compared to controls (P = 0.03). Difference was significant only in men (P = 0.001). Logistic regression models showed an inverse association between height and PD (OR 0.35; CI 0.16, 0.79; P < 0.01 comparing individuals in the highest percentiles of height with those in the lowest). Our results indicate an association between height and PD in men. Considering that dopamine sensitivity in the hypothalamic-pituitary axis is related to adult height, our findings suggest a relationship between PD and factors modulating somatic growth early in life. © 2007 Movement Disorder Society

The aim of this study was to evaluate the effect of levetiracetam on tardive dyskinesia (TD), which is known to be a major limitation of chronic antipsychotic drug therapy, particularly with conventional antipsychotics.Sixteen patients suffering from chronic psychosis with TD were enrolled consecutively. Levetiracetam was given in gradually increasing doses, starting with 125 twice a day until the best clinical benefit was achieved (mean dosage, 2,290 mg; range, 1,000-3,000 mg). Tardive dyskinesia was assessed using the Abnormal Involuntary Movement Scale at baseline and after 1 month and 3 months of treatment with levetiracetam.Compared with baseline, there was a significant improvement in the Abnormal Involuntary Movement Scale score after 1 month still present after 3 months (P0.001). All patients well tolerated levetiracetam, except one who dropped out of the trial after the first 2 weeks owing to excessive drowsiness.The results of this open-label observational study suggest that levetiracetam is a well-tolerated drug and effectively controls TD.

Background and purpose Depressed mood is a common psychiatric problem associated with Parkinson's disease (PD), and studies have suggested a benefit of rasagiline treatment. Methods ACCORDO (see the Appendix) was a 12-week, double-blind, placebo-controlled trial to evaluate the effects of rasagiline 1 mg/day on depressive symptoms and cognition in non-demented PD patients with depressive symptoms. The primary efficacy variable was the change from baseline to week 12 in depressive symptoms measured by the Beck Depression Inventory (BDI-IA) total score. Secondary outcomes included change from baseline to week 12 in cognitive function as assessed by a comprehensive neuropsychological battery; Parkinson's disease quality of life questionnaire (PDQ-39) scores; Apathy Scale scores; and Unified Parkinson's Disease Rating Scale (UPDRS) subscores. Results One hundred and twenty-three patients were randomized. At week 12 there was no significant difference between groups for the reduction in total BDI-IA score (primary efficacy variable). However, analysis at week 4 did show a significant difference in favour of rasagiline (marginal means difference ± SE: rasagiline −5.46 ± 0.73 vs. placebo −3.22 ± 0.67; P = 0.026). There were no significant differences between groups on any cognitive test. Rasagiline significantly improved UPDRS Parts I (P = 0.03) and II (P = 0.003) scores versus placebo at week 12. Post hoc analyses showed the statistical superiority of rasagiline versus placebo in the UPDRS Part I depression item (P = 0.04) and PDQ-39 mobility (P = 0.007) and cognition domains (P = 0.026). Conclusions Treatment with rasagiline did not have significant effects versus placebo on depressive symptoms or cognition in PD patients with moderate depressive symptoms. Although limited by lack of correction for multiple comparisons, post hoc analyses signalled some improvement in patient-rated cognitive and depression outcomes.

The effect of sertraline on the steady-state plasma concentrations of risperidone and its active metabolite 9-hydroxyrisperidone (9-OH-risperidone) was studied in 11 patients with schizophrenia or schizoaffective disorder. To treat concomitant depressive symptoms, additional sertraline, at the dose of 50 mg/d, was administered for 4 weeks to patients stabilized on risperidone (4-6 mg/d). Mean plasma concentrations of risperidone, 9-OH-risperidone, and the active moiety (sum of the concentrations of risperidone and 9-OH-risperidone) did not change significantly during combined treatment with sertraline. At the end of week 4, sertraline dosage was adjusted in some patients on the basis of the individual response and then maintained until the end of week 8. At final evaluation, mean plasma levels of risperidone active moiety were not modified in the 4 patients who were still receiving the initial sertraline dose, but concentrations were slightly but not significantly increased (by a mean 15% over pretreatment) in the subgroup of 5 subjects treated with a final dose of 100 mg/d. In the 2 patients receiving the highest dose of sertraline, 150 mg/d, at week 8 total plasma risperidone concentrations were increased by 36% and 52%, respectively, as compared with baseline values. Sertraline coadministration with risperidone was well tolerated, and no patient developed extrapyramidal symptoms. These findings indicate that sertraline at dosages up to 100 mg/d is not associated with clinically significant changes in plasma risperidone concentrations. However, higher doses of sertraline may elevate plasma risperidone levels, presumably as a result of a dose-dependent inhibitory effect of sertraline on CYP2D6-mediated 9-hydroxylation of risperidone.

OBJECTIVE This study aimed to compare the efficacy and safety of quetiapine and clozapine in parkinsonian patients with dopaminergic psychosis in a randomized, open-label, blinded-rater, parallel group trial. METHODS Forty-five patients with Parkinson disease (PD) and psychosis induced by antiparkinsonian drugs were randomly assigned to receive either quetiapine or clozapine. The duration of the trial was 12 weeks. Forty patients, 20 in each treatment group, completed the study. The final dose of quetiapine (mean +/- SD) was 91 +/- 47 mg/d and that of clozapine 26 +/- 12 mg/d. The severity of psychosis was assessed using the Brief Psychiatric Rating Scale (BPRS) and the Clinical Global Impression Scale-Severity Subscale (CGI-S). The Unified Parkinson's Disease Rating Scale (UPDRS) III was used to assess motor conditions during the study period. The Abnormal Involuntary Movement Scale (AIMS) was performed to evaluate dyskinesias. RESULTS Forty patients, 20 on clozapine and 20 on quetiapine, completed the study. The psychopathologic state improved significantly (P < 0.001) from baseline in both treatment groups. No differences were found between clozapine and quetiapine at any assessment time. Motor conditions remained unchanged after clozapine and quetiapine. Dyskinesias decreased significantly (P < 0.05) in both groups. Side effects were mild, generally transient, and well tolerated. CONCLUSIONS Quetiapine and clozapine appear equally efficacious for treatment of dopaminergic psychosis in patients with PD.

Lower cancer risk in Parkinson's disease (PD) patients compared to the general population has been reported. However, most of the studies were based on death certificates. We designed a case–control study to estimate the association of tumor preceding PD onset and PD. PD patients were matched by age and gender to PD-free individuals, randomly selected from the municipalities of residence of cases. Occurrence of tumors preceding PD onset was assessed through a structured questionnaire. Neoplasms were categorized as benign, malignant, or of uncertain classification, and endocrine-related or not. Odds ratios (OR) were calculated using conditional logistic regression and adjusted for tumor categories and risk factors. We included 222 PD patients. Frequency of cancer was 6.8% for cases, 12.6% for controls. PD patients had a decreased risk for neoplasms (adjusted OR, 0.4; 95% confidence interval [CI], 0.2–0.7). Risk was reduced only for women (adjusted OR, 0.3; 95% CI, 0.1–0.7). PD patients had a decreased risk both for malignant (adjusted OR, 0.6; 95% CI, 0.1–2.5) and nonmalignant neoplasms (adjusted OR, 0.3; 95% CI, 0.1–0.7). Still, risk was decreased for endocrine-related tumors (adjusted OR, 0.3; 95% CI, 0.1–0.9) and non–endocrine-related tumors (adjusted OR, 0.4; 95% CI, 0.1–0.9). Our study confirms the inverse association between PD and neoplasms reported in previous epidemiologic studies. © 2004 Movement Disorder Society

Familial hemiplegic migraine (FHM) is a rare autosomal dominant disorder characterized by episodes of transient hemiparesis followed by headache. Two chromosomal loci are associated to FHM: FHM1 on chromosome 19 and FHM2 on chromosome 1q21-23. Mutations of the alpha-1A subunit of the voltage gated calcium channel (CACNA1A) are responsible for FHM1. FHM2 critical region spans 28 cM, hence hampering the identification of the responsible gene. Here, we report the FHM2 locus refining by linkage analysis on two large Italian families affected by pure FHM. The new critical region covers a small area of 0.9Mb in 1q23 and renders feasible a positional candidate approach. By mutation analysis, we excluded the calsequestrin and two potassium channel genes mapping within the narrowed FHM2 locus.

Similarly to subjects with degenerative parkinsonism, 123I-FP-CIT SPECT has been reported either normal or abnormal in patients with drug-induced parkinsonism (DIP), challenging the notion that parkinsonism might be entirely due to post-synaptic D2-receptors blockade by antipsychotic drugs. In a previous multicenter cross-sectional study conducted on a large sample of patients with schizophrenia, we identified 97 patients who developed parkinsonism with a similar bi-modal distribution of DAT-SPECT. In this longitudinal study, we reported clinical and imaging features associated with progression of motor disability over 2-year follow-up in 60 out of those 97 patients with schizophrenia and parkinsonism who underwent 123I-FP-CIT SPECT at baseline evaluation (normal SPECT = 33; abnormal SPECT = 27). As second end-point, chronic response to levodopa over a 3-month period was tested in a subgroup of subjects. Motor Unified Parkinson's Disease Rating Scale (UPDRS) at follow-up significantly increased in patients with abnormal SPECT. Specifically, a 6-point worsening was demonstrated in 18.5% of the subjects with abnormal SPECT and in none of the subjects with normal SPECT. Levodopa treatment improved motor UPDRS only in the group with abnormal SPECT. After adjustment for possible confounders, linear regression analysis demonstrated that abnormal SPECT findings at baseline were the only predictor of motor disability progression and of better outcome of levodopa treatment. Our results support the notion that a degenerative disease might underlie parkinsonism in a minority of schizophrenic patients chronically exposed to antipsychotics. Functional imaging of the dopamine transporter can be helpful to select this patient sub-group that might benefit from levodopa therapy.

Current epidemiologic data on the association between occupational exposures and Parkinson's disease (PD) are inconsistent. In a case-control study, we investigated the associations between occupation and PD and between education and PD. The cases (n = 62) were those identified in a prevalence survey (door-to-door, two-phase) of three Sicilian municipalities, as a November 1, 1987. We then randomly selected from the general population two controls for each case, matched for age ( +/- year), sex, and municipality (n = 124). Information on current and past occupations and education for cases and controls was obtained during the survey. Subjects who worked for most of their lives as farmers were not at increased risk of PD (OR = 0.6; 95% CI = 0.3-1.3). Neither were subjects who worked for most of their lives in other occupations (e.g., housewives, fishermen, factory workers, salesmen, craftsmen, clerks). PD was not associated with low education. Our findings suggest that farming, as a broad occupational category, does not play a major role in the causation of PD.

Parkinson'sdisease (PD) is an extra-pyramidal neurodegenerative disorder, in which alterations of the immune system are involved. Interleukin (IL)-15 stimulates cellular immune response and induces growth and differentiation of various immune cells. RANTES, promoting leukocyte infiltration to sites of inflammation, mediates the trafficking and homing of immune cells. To clarify the potential effect of levodopa on the immunological network of PD, we analyzed IL-15 and RANTES serum levels in PD patients, treated or not with levodopa, and in healthy donors. Levodopa-treated patients showed significantly higher IL-15 and RANTES circulating levels with respect to healthy controls and higher, although not significantly, levels with respect to untreated patients. So, we hypothesize that the immunological alterations found in PD may be linked, at least in part, to levodopa therapy.

Non-motor symptoms are gaining relevance in Parkinson's disease (PD) management but little is known about their progression and contribution to deterioration of quality of life. We followed prospectively 707 PD patients (62 % males) for 2 years. We assessed non-motor symptoms referred to 12 different domains, each including 1-10 specific symptoms, as well as motor state (UPDRS), general cognition, and life quality. HoehnYahr (HY) stage was used to categorize patient status (I-II mild; III moderate; IV-V severe). We found that individual non-motor symptoms had variable evolution over the 2-year follow-up with sleep, gastrointestinal, attention/memory and skin disturbances (hyperhidrosis and seborrhea) becoming more prevalent and psychiatric, cardiovascular, and respiratory disorders becoming less prevalent. Development of symptoms in the cardiovascular, apathy, urinary, psychiatric, and fatigue domains was associated with significant life-quality worsening (p0.0045, alpha with Bonferroni correction). During the observation period, 123 patients (17 %) worsened clinically while 584 were rated as stable. There was a fivefold greater increase in UPDRS motor score in worse compared with stable patients over 24 months (p0.0001 vs. baseline both in stable and worse group). The total number of reported non-motor symptoms increased over 24 months in patients with motor worsening compared to stable ones (p0.001). Thirty-nine patients died (3.4 % of patients evaluable at baseline) with mean age at death of 74 years. Deceased patients were older, had significantly higher HY stage and motor score, and reported a greater number of non-motor symptoms at baseline. In conclusion, overall non-motor symptom progression does not follow motor deterioration, is symptom-specific, and only development of specific domains negatively impacts quality of life. These results have consequences for drug studies targeting non-motor features.

Corrigendum to “[]FP-CIT single photon emission computed tomography findings in drug-induced Parkinsonism” [Schizophr. Res. 113 (2009) 41–48] Michele Tinazzi , Andrea Cipriani, Angela Matinella⁎, Antonino Cannas, Paolo Solla , Alessandra Nicoletti , Mario Zappia, Letterio Morgante, Francesca Morgante, Claudio Pacchetti , Massimo Sciarretta , Carlo Dallocchio, Simone Rossi, Maria Malentacchi, Roberto Ceravolo , Daniela Frosini , Stelvio Sestini , Tommaso Bovi , Corrado Barbui

Two-phase prevalence surveys with screening (phase 1) and examination (phase 2) are useful for some chronic diseases. Attrition, which may bias estimates, occurs in either phase because some eligible subjects die before contact, some refuse to cooperate, some are incapacitated, and some are unreachable. This investigation relates to a survey of neurologic diseases conducted in three municipalities of Sicily (prevalence date, November 1, 1987) and considers the attrition experienced and the use of proxy respondents in phase 1 and auxiliary information in phase 2 to offset, in part, this attrition. Regarding case finding, the salvage effort was more productive for decreased and incapacitated subjects. The age, sex, and household size of the subject were related to phase 1 attrition, but only age was related for all four attrition groups--deceased, refusing, incapacitated, and unreachable subjects. On the basis of information from proxy respondents, the educational levels of refusing and unreachable subjects were compared with those of subjects screened directly. Refusing subjects were less educated, and unreachable subjects were more educated. The proxy respondent performance, as indicated by "don't know" responses, was better with screening items concerning facial paralysis and mouth drooping (and not limb sensory abnormalities or impaired consciousness), better with younger subjects, and worse with refusing or incapacitated subjects.

Drug-induced parkinsonism (DIP) in patients treated with antipsychotic drugs is considered a form of post-synaptic parkinsonism, caused by D2-receptor blockade. Recent studies, however, carried out on small and heterogeneous patient samples, have shown that DIP may be associated with [(123)I]FP-CIT single photon emission computed tomography (SPECT) abnormalities, which are markers of dopamine nigrostriatal terminal defect. In the present study, outpatients fulfilling the DSM-IV criteria for schizophrenia and treated with antipsychotics for at least 6 months, were enrolled in order to estimate the prevalence of DIP and, among patients with DIP, the prevalence of [(123)I]FP-CIT SPECT abnormalities. Socio-demographic and clinical variables associated with the presence of DIP and SPECT abnormalities were also assessed. DIP was diagnosed in 149 out of 448 patients with schizophrenia (33%). Age, use of long-acting antipsychotics and a positive family history of parkinsonism were the only demographic variables significantly associated with the development of DIP. Neuroimaging abnormalities were found in 41 of 97 patients who agreed to undergo [(123)I]FP-CIT SPECT (42%). Only age differentiated this group of patients from those with normal imaging. These preliminary findings suggest that D2-receptor blockade may coexist with a dopamine nigrostriatal terminal defect, as assessed by [(123)I]FP-CIT SPECT abnormalities, in a relevant proportion of DIP patients. Longitudinal studies should be designed with the aim of improving our understanding of the mechanisms of pre-synaptic abnormalities in DIP patients and identifying specific treatment strategies.

Some studies have suggested an overlap of clinical and genetic findings between essential tremor (ET) and Parkinson’s disease (PD). The first genome-wide association study in ET showed a significant association with the rs9652490 SNP of the leucine-rich repeat and Ig domain containing 1 (LINGO1) gene. Since patients with PD have higher LINGO1 expression levels compared to healthy controls, and animal models of PD show elevated LINGO1 protein levels after experimentally induced damage in the striatum, it can be inferred that LINGO1 is probably involved in PD pathophysiology. In this study, we performed a genetic association analysis of the rs9652490 and rs11856808 SNPs in Italian PD patients and controls to assess the role of these variants in our population. A total of 567 patients with PD and 468 control subjects were enrolled in five Movement Disorder centers located in Central-Southern Italy. Both variants were significantly associated with PD under a recessive model of inheritance before applying the Bonferroni correction. The GG genotype of rs9652490 and the TT genotype of rs11856808 were less frequent in patients than in controls, suggesting a protective effect against the disease. However, after stringent correction, only the P-values obtained from allele and genotype comparisons of the rs11856808 SNP remained significant. Our findings suggest that LINGO1 plays a certain role in the development of PD in the Italian population and represents an interesting candidate gene responsible for PD, due to its involvement in neurological processes.

In three municipalities of Sicily, a prevalence survey of major neurological diseases was conducted door-to-door using screening and examination to find cases. This was the first large-scale neuroepid

PURPOSE: To prospectively assess sensitivity and specificity of magnetic resonance (MR) imaging measurements of midbrain, pons, middle cerebellar peduncles (MCPs), and superior cerebellar peduncles (SCPs) for differentiating progressive supranuclear palsy (PSP) from Parkinson disease (PD) and Parkinson variant of multiple system atrophy (MSA-P), with established consensus criteria as reference standard. MATERIALS AND METHODS: All study participants provided informed consent; study was approved by the institutional review board. Pons area, midbrain area, MCP width, and SCP width were measured in 33 consecutive patients with PSP (16 possible, 17 probable), 108 consecutive patients with PD, 19 consecutive patients with MSA-P, and 50 healthy control participants on T1-weighted MR images. The pons area-midbrain area ratio (P/M) and MCP width-SCP width ratio (MCP/SCP) were also used, and an index termed MR parkinsonism index was calculated [(P/M).(MCP/SCP)]. Differences in MR imaging measurements among groups were evaluated with Kruskal-Wallis test, Mann-Whitney U test, and Bonferroni correction. RESULTS: Midbrain area and SCP width in patients with PSP (23 men, 10 women; mean age, 69.3 years) were significantly (P < .001) smaller than in patients with PD (62 men, 46 women; mean age, 65.8 years), patients with MSA-P (five men, 14 women; mean age, 64.0 years), and control participants (25 men, 25 women; mean age, 66.6 years). P/M and MCP/SCP were significantly larger in patients with PSP than in patients in other groups and control participants. All measurements showed some overlap of values between patients with PSP and patients from other groups and control participants. MR parkinsonism index value was significantly larger in patients with PSP (median, 19.42) than in patients with PD (median, 9.40; P < .001), patients with MSA-P (median, 6.53; P < .001), and control participants (median, 9.21; P < .001), without overlap of values among groups. No patient with PSP received a misdiagnosis when the index was used (sensitivity and specificity, 100%). CONCLUSION: The MR parkinsonism index can help distinguish patients with PSP from those with PD and MSA-P on an individual basis.

Background: Only a restricted number of population studies based on long-term prognosis after a stroke have been published. We analyzed long-term survival and outcome in insular first-ever stroke population from the Aeolian Archipelago. Subjects and methods: From 1 July, 1999 to 30 June 2002, 62 patients with first-ever stroke were recruited to evaluate short-term incidence and outcome. Information for every patient was collected by phone interviews after 3 months, 1 year, and 4 years. Results: 30 days case fatality rate was 24.2% (95% C.I. 14.22 to 36.75). Fifty-one percent (95% C.I. 35.8 to 66.3) of patients died before last survey and 39.1% died during the first year of follow-up. Annual approximate death risk amounted to about 10%. Results: The cerebrovascular causes were the most frequent causes of death (65.2%). A high level of invalidity at 4 years was present in many survivors (40%). Results: None of the deceased had followed physio-kinesitherapy, or applied for equipment or services. Conclusion: More attentive medical care for stroke patients could help improve outcome, reducing mortality for patients from the Aeolian island, who already showed a low incidence.

The arginine growth hormone (GH) stimulation test differentiates the Parkinsonian variant of multiple system atrophy (MSA-P) from idiopathic Parkinson's disease (PD). Our aim was to evaluate the accuracy of the arginine GH stimulation test in distinguishing between PSP, MSA-P, and PD. We measured the GH response to arginine in serum samples of 26 MSA-P, 23 PSP, and 26 PD patients, and in 80 healthy controls. We used ANOVA followed by the Bonferroni test to compare GH values and peaks among groups. We used receiver operating characteristic curve analysis to establish the arginine cut-off level that best differentiated between MSA-P, PSP, and PD. The GH peak was significantly lower (P0.01) in MSA-P (1.46 +/- 0.29 microg/L) than in both PD (8.74 +/- 0.98 microg/L) and PSP (6.64 +/- 0.82 microg/L) patients, and controls (8.59 +/- 0.44 microg/L). Growth hormone peaked later in PSP patients than in PD patients and controls. At a cut-off level of 4 microg/L, arginine test distinguished MSA-P from PD with a sensitivity of 92% and a specificity of 96%, and MSA-P from PSP with a sensitivity of 78% and a specificity of 96%. The GH response to arginine differentiates MSA-P from PD and PSP with a good diagnostic accuracy. The neuroendocrine response to arginine of PSP patients differed from that of MSA-P patients, but was not identical to that of normal controls and PD patients. Our results suggest that the impairment of the central mechanisms modulating GH release differs between PSP and MSA-P.

Myocardial (123)Metaiodobenzylguanidine (MIBG) enables the assessment of postganglionic sympathetic cardiac innervation. MIBG uptake is decreased in nearly all patients with Parkinson's disease (PD). Our objective was to evaluate MIBG uptake in patients with genetic PD. We investigated MIBG uptake in 14 patients with PD associated with mutations in different genes (Parkin, DJ-1, PINK], and leucine-rich repeat kinase 2 -LRRK2), in 15 patients with idiopathic PD, and 10 control subjects. The myocardial MIGB uptake was preserved in 3 of the 4 Parkin-associated Parkinsonisms, in I of the 2 patients with DJ-1 mutations, in 1 of the 2 brothers with PINK] mutations, in 3 of the 6 unrelated patients with Gly2019Ser mutation in the LRRK2 gene, whereas it was impaired in all patients with idiopathic PD. MIBG was preserved in all control subjects. Our study shows that myocardial MIGB uptake was normal in 8 of 14 patients with genetic PD, suggesting that cardiac sympathetic denervation occurs less frequently in genetic PD than in idiopathic PD. Our findings also demonstrate that MIGB uptake has a heterogeneous pattern in genetic PD, because it was differently impaired in patients with different mutations in the same gene or with the same gene mutation. (c) 2007 Movement Disorder Society.

Aim of this study was to investigate the relationship between height in young adult age and Parkinson's disease (PD) risk. We included 266 persons affected by idiopathic PD. Patients were matched by age and sex to 266 controls by a random selection from the municipality of residence. We collected information about height preceding PD from official documents where these characteristics referred to young adult age (nearly 30 years). We compared height in cases and controls by calculating differences in mean distribution and by chi(2) analyses. Crude and adjusted odds ratios (OR) and 95% confidence intervals (CI) were calculated by logistic regression models. Mean height was significantly lower in persons affected by PD compared to controls (P = 0.03). Difference was significant only in men (P = 0.001). Logistic regression models showed an inverse association between height and PD (OR 0.35; CI 0.16, 0.79; P0.01 comparing individuals in the highest percentiles of height with those in the lowest). Our results indicate an association between height and PD in men. Considering that dopamine sensitivity in the hypothalamic-pituitary axis is related to adult height, our findings suggest a relationship between PD and factors modulating somatic growth early in life.

Objective To estimate prevalence of Parkinson's disease (PD) and other types of parkinsonism in the Aeolian Archipelago, Sicily. Methods We studied the frequency of PD and other types of parkinsonism in the Aeolian Archipelago (population 13,431). All potential cases were identified from available medical information sources. To ensure the completeness of the case-findings, a screening questionnaire was also mailed to residents aged 40 years and over. Subjects were considered prevalent if they fulfilled the SNES diagnostic criteria for PD, on prevalence day (January 1, 2001). Results We identified 17 patients with parkinsonism from medical sources, and 4 from mail-survey. Prevalence for all types of parkinsonism was 156.3/100,000 (95% CI 99.4–234.8). Fourteen subjects fulfilled diagnostic criteria for PD giving a crude prevalence of 104.2/100,000 (95% CI 59.4–170.7) and 422.5/100,000 in the population aged 60 years and over. Conclusions Prevalence of all types of parkinsonism and PD found in the Aeolian Archipelago is lower than that previously reported in Sicily.

We used a CAPSIT-based questionnaire to estimate the percentage of parkinsonian patients suitable for subthalamic nucleus (STN) deep brain stimulation (DBS) in a movement disorders clinic. We found that out of 641 consecutive PD patients only 1.6% fulfilled strict STN-DBS criteria. When we applied more flexible criteria, the percentage of eligibility increased to 4.5%. Most patients (60%) were ineligible because they did not satisfy multiple questionnaire items. Items related to disease severity were responsible for the largest number of exclusions. This knowledge will help make decisions on resource allocation in centres wishing to start DBS surgery.

a Department of Neurology, Institute of Research and Medical Care, IRCCS San Raffaele, Rome, Italy b Department for Parkinson's Disease, IRCCS San Camillo, Venice, Italy c School of Medicine, University of Salerno, Salerno, Italy d U.O. Neurologia Ospedale Civile Maggiore, Borgo Trento, Verona, Italy e Clinica Neurologica I Policlinico Universitario, Catania, Italy f CeSI-Centro Studi Invecchiamento Fondazione Universit a Gabriele D'Annunzio, Chieti, Italy g Neurologia Istituto Mediterraneo Neuromed, Isernia, Italy h Dipartimento di Neuroscienze Universit a di Messina, Messina, Italy i U.O. Neurologia Ospedale Versilia, Lucca, Italy j Neurologia 4 A.S.O. Molinette, Turin, Italy k Neurologia Ospedale di Bolzano, Bolzano, Italy l Neurologia I Istituto Nazionale Neurologico C. Besta, Universit a Cattolica del Sacro Cuore, Milan, Italy m Novartis Pharma Italia, Medical Department, Origgio, Italy n Department of Neurosciences, University of Genoa, Genoa, Italy

Clinical differentiation of parkinsonian syndromes such as the Parkinson variant of multiple system atrophy (MSA-P) and progressive supranuclear palsy (PSP) from Parkinson's disease is difficult in the early stage of the disease. In order to identify objective markers for differential diagnosis, we studied these three groups of patients with diffusion-weighted MRI (DWI). Sixteen MSA-P patients, 16 with PSP, 16 with Parkinson's disease and 15 healthy volunteers were studied. Regional apparent diffusion coefficients (rADC) were determined in different brain regions including basal ganglia, thalamus, white matter, pons and middle cerebellar peduncles (MCPs). rADC calculated in the MCP completely differentiated MSA-P patients (median: 0.93 x 10(-3) mm2/s) from PSP patients (median: 0.82 x 10(-3) mm2/s, P < 0.001), Parkinson's disease patients (median: 0.79 x 10(-3) mm2/s, P < 0.001) and healthy volunteers (median: 0.81 x 10(-3) mm2/s, P < 0.001). Other regions considered showed an overlapping among groups. DWI discriminates MSA-P from PSP and Parkinson's disease and healthy volunteers on the basis of MCP rADC values. These in vivo results confirm the pathological findings that the majority of MSA-P patients have moderate or severe degenerative changes not only in the nigrostriatal but also in the olivopontocerebellar systems. Our findings indicate that, in order to substantially contribute to the in vivo differential diagnosis of MSA-P, PSP and Parkinson's disease, rADC measurements should not be limited to the basal ganglia but should also include the MCP.

Background: The clinical condition of advanced Parkinson's disease ( PD) patients is often complicated by motor fluctuations and dyskinesias which are difficult to control with available oral medications. Objective: To compare clinical and neuropsychological 12 month outcome following subcutaneous apomorphine infusion (APO) and chronic deep brain stimulation of the subthalamic nucleus (STN-DBS) in advanced PD patients. Methods: Patients with advanced PD and medically untreatable fluctuations underwent either APO (13 patients) or STN-DBS (12 patients). All patients were clinically (UPDRS-III, AIMS, 12 h on-off daily) and neuropsychologically (MMSE, Hamilton-17 depression, NPI) evaluated at baseline and at 12 months. APO was discontinued at night. Results: At 12 months APO treatment (74.78 +/- 24.42 mg/day) resulted in significant reduction in off time ( 251%) and no change in AIMS. Levodopa equivalent medication doses were reduced from 665.98 +/- 215 mg/ day at baseline to 470 +/- 229 mg/ day. MMSE, NPI, and Hamilton depression scores were unchanged. At 12 months STN-DBS resulted in significant clinical improvement in terms of reduction in daily off time (276%) and AIMS (281%) as well as levodopa equivalent medication doses (980 +/- 835 to 374 +/- 284 mg/ day). Four out of 12 patients had stopped oral medications. MMSE was unchanged (from 28.6 +/- 0.3 to 28.4 +/- 0.6). Hamilton depression was also unchanged, but NPI showed significant worsening (from 6.58 +/- 9.8 to 18.16 +/- 10.2; p < 0.02). Category fluency also declined. Conclusions: Both APO and STN- DBS resulted in significant clinical improvement in complicated PD. STNDBS resulted in greater reduction in dopaminergic medications and provided 24 h motor benefit. However, STN-DBS, unlike APO, appears to be associated with significant worsening on NPI resulting from long term behavioral problems in some patients.

Objective To assess motor cortex excitability, motor preparation and imagery in patients with unilateral cerebellar stroke with damage of the dentate nucleus by using transcranial magnetic stimulation (TMS). Method Eight patients with unilateral cerebellar lesions due to tromboembolic stroke and 10 age matched healthy subjects were enrolled. Resting (RMT) and active (AMT) motor threshold, cortical and peripheral silent period, evaluation of motor imagery, reaction time and premovement facilitation of motor evoked potential (MEP) were tested bilaterally using TMS. Results The RMT and AMT were found to be increased contra lateral to the affected cerebellar hemisphere while the cortical silent period was prolonged. In addition the amount of MEP facilitation during motor imagery and the pre-movement facilitation were reduced in the motor cortex contra lateral to the affected cerebellar hemisphere. The reaction time, performed with the symptomatic hand, was slower. Conclusions On the whole, our data confirm a role for the cerebellum in maintaining the excitability of primary motor area. Furthermore, patients with unilateral cerebellar stroke exhibit lateralized deficit of motor preparation and motor imagery. Significance Our results add to evidence that cerebellum contributes to specific aspects of motor preparation and motor imagery.

PURPOSE: To prospectively assess if middle cerebellar peduncle (MCP) atrophy, evaluated at magnetic resonance (MR) imaging, can help differentiate multiple system atrophy (MSA) from Parkinson disease (PD). MATERIALS AND METHODS: All participants provided informed consent for participation in the study, which was approved by the institutional review board. Sixteen consecutive patients with MSA, 26 consecutive patients with PD, and 14 healthy control subjects were examined with MR imaging. Images were interpreted independently by two experienced neuroradiologists blinded to clinical information, who visually inspected the images for the presence or absence of putaminal atrophy, putaminal hypointensity, slitlike hyperintensity in the posterolateral margin of the putamen, brainstem atrophy, hyperintensity of the MCP, and cruciform hyperintensity of the pons. Measurements of MCP width on T1-weighted volumetric spoiled gradient-echo images were performed in all subjects. Differences in MCP width among the groups were evaluated by using the Kruskall-Wallis test, followed by the Mann-Whitney U test for multiple comparisons and Bonferroni correction. RESULTS: All patients (mean age, 63.88 years; range, 55-72 years) with MSA had at least one of the features commonly observed in this disease on MR images, whereas control subjects (mean age, 66.93 years; range, 61-77 years) and all but one patient with PD (mean age, 65.31 years; range, 51-79 years) had normal MR images. The average MCP width was significantly smaller in patients with MSA (6.10 mm+/-1.18 [standard deviation]) than in those with PD (9.32 mm+/-0.77, P

Objective Multiple system atrophy (MSA) may be difficult to distinguish from idiopathic Parkinson's disease (PD). Our aim was to evaluate the accuracy of the arginine growth hormone (GH) stimulation test in distinguishing between MSA and PD in large populations of patients. Methods We measured the GH response to arginine in 69 MSA (43 MSAp [parkinsonism as the main motor feature] and 26 MSAc [cerebellar features predominated]) patients, 35 PD patients, and 90 healthy control subjects. We used receiver-operating curve analysis to establish the arginine cutoff value that best differentiated between MSA and PD. Results The GH response to arginine was significantly lower (p < 0.01) in MSA than in either PD patients or control subjects. At a cutoff level of 4μg/L, arginine distinguished MSAp from PD with a sensitivity and specificity of 91% and MSAc from PD with a sensitivity of 96% and specificity of 91%. The arginine test had a positive predictive value for MSA of 95%. The GH response to arginine was not affected by disease duration or severity, MSA motor subtype, pyramidal signs, response to dopaminergic therapy, or magnetic resonance imaging findings. Interpretation The GH response to arginine differentiates MSA from PD with a high diagnostic accuracy. The results suggest an impairment of cholinergic central systems modulating GH release in MSA. Ann Neurol 2006