Publications by authors named "Florence Cormier-Dequaire"

22 Publications

  • Page 1 of 1

Long-term effect of apomorphine infusion in advanced Parkinson's disease: a real-life study.

NPJ Parkinsons Dis 2021 Jun 11;7(1):50. Epub 2021 Jun 11.

Neurology Department, Pitié-Salpêtrière Hospital, AP-HP, Paris, France.

Long-term effects of continuous subcutaneous apomorphine infusion (CSAI) on health-related quality of life (HRQoL) and predictors of CSAI discontinuation are poorly known. Data from consecutive advanced Parkinson's disease patients treated in routine care were retrospectively collected over 24 months after CSAI initiation, with a focus on the 39-item Parkinson's disease questionnaire (PDQ-39). We determined predictors of CSAI discontinuation and HRQoL improvement using multiple regression analysis. Of the 110 subjects evaluated over a 2-year period, 35% discontinued CSAI. Of those who continued treatment, HRQoL remained stable with a sustained reduction in motor fluctuations. The observed effect on dyskinesias was mild and transient. Of note, patients with preexisting impulse control disorders showed an overall good tolerability. PDQ-39 was the only baseline predictor of HRQoL improvement after 2 years of treatment. The presence of dyskinesias, poorer psychological status, shorter disease duration, male sex, and worse OFF state were predictors of discontinuation. Best candidates for CSAI are patients with: (i) poor baseline HRQoL and (ii) marked motor fluctuations.
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http://dx.doi.org/10.1038/s41531-021-00194-7DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8196159PMC
June 2021

Genome-wide survival study identifies a novel synaptic locus and polygenic score for cognitive progression in Parkinson's disease.

Nat Genet 2021 06 6;53(6):787-793. Epub 2021 May 6.

Translational Genomics Core of Partners HealthCare Personalized Medicine, Cambridge, MA, USA.

A key driver of patients' well-being and clinical trials for Parkinson's disease (PD) is the course that the disease takes over time (progression and prognosis). To assess how genetic variation influences the progression of PD over time to dementia, a major determinant for quality of life, we performed a longitudinal genome-wide survival study of 11.2 million variants in 3,821 patients with PD over 31,053 visits. We discover RIMS2 as a progression locus and confirm this in a replicate population (hazard ratio (HR) = 4.77, P = 2.78 × 10), identify suggestive evidence for TMEM108 (HR = 2.86, P = 2.09 × 10) and WWOX (HR = 2.12, P = 2.37 × 10) as progression loci, and confirm associations for GBA (HR = 1.93, P = 0.0002) and APOE (HR = 1.48, P = 0.001). Polygenic progression scores exhibit a substantial aggregate association with dementia risk, while polygenic susceptibility scores are not predictive. This study identifies a novel synaptic locus and polygenic score for cognitive disease progression in PD and proposes diverging genetic architectures of progression and susceptibility.
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http://dx.doi.org/10.1038/s41588-021-00847-6DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8459648PMC
June 2021

Early cognitive decline after bilateral subthalamic deep brain stimulation in Parkinson's disease patients with GBA mutations.

Parkinsonism Relat Disord 2020 07 9;76:56-62. Epub 2020 Jun 9.

Sorbonne Université, Inserm U1127, CNRS UMR 7225, Institut du Cerveau et de la Moelle épinière, Paris, France; Assistance Publique Hôpitaux de Paris, Hôpital Pitié-Salpêtrière, Département de Neurologie, Clinical Research Center Neurosciences, Paris, France. Electronic address:

Background: Subthalamic nucleus deep brain stimulation (STN-DBS) has demonstrated its efficacy on motor complications in advanced Parkinson's disease (PD) but does not modify disease progression. Genetic forms of PD have been associated with different cognitive progression profiles.

Objective: To assess the effect of PD-related genetic mutations on cognitive outcome after STN-DBS.

Methods: Patients with STN-DBS were screened for LRRK2, GBA, and PRKN mutations at the Pitié-Salpêtrière Hospital between 1997 and 2009. Patients with known monogenetic forms of PD from six other centers were also included. The Mattis Dementia Rating Scale (MDRS) was used to evaluate cognition at baseline and one-year post-surgery. The standardized Unified PD Rating Scale (UPDRS) evaluation On and Off medication/DBS was also administered. A generalized linear model adjusted for sex, ethnicity, age at onset, and disease duration was used to evaluate the effect of genetic factors on MDRS changes.

Results: We analyzed 208 patients (131 males, 77 females, 54.3 ± 8.8 years) including 25 GBA, 18 LRRK2, 22 PRKN, and 143 PD patients without mutations. PRKN patients were younger and had a longer disease duration at baseline. A GBA mutation was the only significant genetic factor associated with MDRS change (β = -2.51, p = 0.009). GBA mutation carriers had a more pronounced post-operative MDRS decline (3.2 ± 5.1) than patients with LRRK2 (0.9 ± 4.8), PRKN (0.5 ± 2.7) or controls (1.4 ± 4.4). The motor response to DBS was similar between groups.

Conclusion: GBA mutations are associated with early cognitive decline following STN-DBS. Neuropsychological assessment and discussions on the benefit/risk ratio of DBS are particularly important for this population.
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http://dx.doi.org/10.1016/j.parkreldis.2020.04.002DOI Listing
July 2020

Genetic and Phenotypic Basis of Autosomal Dominant Parkinson's Disease in a Large Multi-Center Cohort.

Front Neurol 2020 28;11:682. Epub 2020 Jul 28.

Sorbonne Université, Unité Mixte de Recherche (UMR) 1127, Paris, France.

, and are unequivocally associated with autosomal dominant Parkinson's disease (PD). We evaluated the prevalence of , and mutations and associated clinical features in a large French multi-center cohort of PD patients. Demographic and clinical data were collected for 1,805 index cases (592 with autosomal dominant inheritance and 1,213 isolated cases) since 1990. All probands were screened with TaqMan assays for Gly2019Ser. In the absence of this mutation, the coding sequences of the three genes were analyzed by Sanger sequencing and/or next-generation sequencing. The data for the three genes were analyzed according to age at onset, family history, ethnic origin and clinical features. We identified 160 index cases (8.9%) with known pathogenic variants: 138 with pathogenic variants (7.6%), including 136 with the Gly2019Ser mutation, 19 with point mutations or genomic rearrangements (1.1%), and three with the Asp620Asn mutation (0.16%). Mutation frequencies were higher in familial than isolated cases, consistent with autosomal dominant inheritance (12.0 vs. 7.3%; OR 1.7, 95% CI [1.2-2.4], = 0.001). PD patients with variants were more likely to have higher rates of late-onset PD (>50 years; OR 1.5, 95% CI [1.0-2.1], = 0.03), whereas those with mutations tended to have earlier age at onset disease (≤ 50 years, = 0.06). The clinical features of carriers and those without any pathogenic variants in known PD-associated genes were similar. The likelihood of detecting disease-causing mutations was higher in cases compatible with autosomal dominant inheritance.
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http://dx.doi.org/10.3389/fneur.2020.00682DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7399219PMC
July 2020

Exome Sequencing Reveals Signal Transduction Genes Involved in Impulse Control Disorders in Parkinson's Disease.

Front Neurol 2020 21;11:641. Epub 2020 Jul 21.

Sorbonne Université, INSERM UMRS 1127, CNRS UMR 7225, Institut du Cerveau et de la Moelle, ICM, Paris, France.

Impulse control disorders (ICDs) frequently complicate dopamine agonist (DA) therapy in Parkinson's disease (PD). There is growing evidence of a high heritability for ICDs in the general population and in PD. Variants on genes belonging to the reward pathway have been shown to account for part of this heritability. We aimed to identify new pathways associated with ICDs in PD. Thirty-six Parkinsonian patients on DA therapy with ( = 18) and without ICDs ( = 18) matched on age at PD's onset, and gender was selected to represent the most extreme phenotypes of their category. Exome sequencing was performed, and variants with a strong functional impact in brain-expressed genes were selected. Allele frequencies and their distribution in genes and pathways were analyzed with single variant and SKAT-O tests. The 10 most associated variants, genes, and pathways were retained for replication in the Parkinson's progression markers initiative (PPMI) cohort. None of markers tested passed the significance threshold adjusted for multiple comparisons. However, the "Adenylate cyclase activating" pathway, one of the top associated pathways in the discovery data set ( = 1.6 × 10) was replicated in the PPMI cohort and was significantly associated with ICDs in a pooled analysis (combined value 3.3 × 10). Two of the 10 most associated variants belonged to genes implicated in cAMP and ERK signaling (rs34193571 in = 5 × 10; rs1877652 in = 8 × 10) although non-significant after Bonferroni correction. Our results suggest that genes implicated in the signaling pathways linked to G protein-coupled receptors participate to genetic susceptibility to ICDs in PD.
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http://dx.doi.org/10.3389/fneur.2020.00641DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7385236PMC
July 2020

Examining the Reserve Hypothesis in Parkinson's Disease: A Longitudinal Study.

Mov Disord 2019 11 13;34(11):1663-1671. Epub 2019 Sep 13.

CESP, Fac. de médecine - Univ. Paris-Sud, Fac. de médecine - UVSQ, INSERM, Université Paris-Saclay, 94805, Villejuif, France.

Background: Whether reserve plays a role in Parkinson's disease (PD) patients has received less attention than in dementia and has been mainly examined in relation with cognitive function.

Objective: To investigate whether reserve plays a role in the severity and progression of motor, cognitive, and nonmotor PD symptoms by examining whether education level (proxy of reserve) is associated with baseline performance and rate of progression.

Methods: We used data from a longitudinal cohort of PD patients (≤5-year disease duration at baseline) annually followed up to 5 years (n = 393; 41% women; mean age = 62.3 years, standard deviation = 10.0; mean disease duration = 2.6 years, standard deviation = 1.5). We examined the relationship of education with time to reach Hoehn and Yahr stage ≥3 using Cox regression and with baseline severity and progression of motor (Movement Disorder Society-Unified Parkinson's Disease Rating Scale parts II and III, gait speed), cognitive (Mini-Mental State Examination), and nonmotor (depression, anxiety, nonmotor symptoms scale, quality of life) symptoms using mixed models.

Results: Education level was not associated with age at onset or diagnosis. Compared with the low-education group, the incidence of Hoehn and Yahr ≥3.0 was 0.42 times lower (95% confidence interval, 0.22-0.82, P = 0.012) in the high-education group. Higher education was associated with better baseline motor function (P < 0.001), but not with the rate of motor decline (P > 0.15). Similar results were observed for cognition. Education was not associated with nonmotor symptoms.

Conclusions: Higher education is associated with better baseline motor/cognitive function in PD, but not with rate of decline, and with a lower risk of reaching Hoehn and Yahr ≥3 during the follow-up. Our observations are consistent with a passive reserve hypothesis for motor/cognitive symptoms. © 2019 International Parkinson and Movement Disorder Society.
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http://dx.doi.org/10.1002/mds.27854DOI Listing
November 2019

Are PSP patients included in clinical trials representative of the general PSP population?

Parkinsonism Relat Disord 2019 09 10;66:202-206. Epub 2019 Jul 10.

Sorbonne Université, Assistance Publique Hôpitaux de Paris, Institut du Cerveau et de la Moelle épinière, ICM, Inserm U 1127, CNRS UMR 7225, Department of Neurology, Hôpital Pitié-Salpêtrière, F-75013, Paris, France. Electronic address:

Background: Progressive supranuclear palsy (PSP) is a rare parkinsonian syndrome with a wide spectrum of clinical presentations. Recently, the MDS published revised diagnosis criteria to provide early and reliable diagnosis of PSP and its variants. Two large randomized clinical trials were initiated in 2017, but the question remains regarding the extrapolation of their results to the general PSP population.

Objective: To determine if PSP patients included in clinical trials are representative of the general PSP population.

Methods: We conducted a single center retrospective study of PSP patients referred to a tertiary department of Neurology (Pitié-Salpêtrière Hospital, Paris) for clinical diagnosis and clinical trial inclusion, over a 12-month period. We collected and analyzed gender, age at examination, age at disease onset, disease duration, and core clinical features regarding oculo-motor dysfunction, postural instability, akinesia and cognitive dysfunction, and inclusion/exclusion criteria of clinical trials to assess eligibility for inclusion. We assessed the relative proportions of different PSP subtypes, as defined by the MDS-PSP criteria, in the whole population compared to patients eligible in trials.

Results: 206 PSP patients were included, among which 175 (85%) were diagnosed with probable PSP-Richardson's syndrome (RS) subtype, with a mean age of 73 and mean disease duration of 5 years. Among those patients, 29 (21%) were eligible (age 71 ± 10.7, disease duration 3.1 ± 1.2 years) and 19 were included in trials, all with a diagnosis of probable PSP-RS. As compared to the whole population, patients included in clinical trials tended to be younger, and showed more PSP-RS subtypes (p < 0.05).

Conclusion: The PSP population included in trials is very similar to the general PSP population, but younger, with shorter disease duration. By definition, only probable PSP subtypes are included in clinical trials. The time window for inclusion is short because of diagnosis delay, fast disease progression and old age of the population.
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http://dx.doi.org/10.1016/j.parkreldis.2019.07.012DOI Listing
September 2019

Clinical and anatomical predictors for freezing of gait and falls after subthalamic deep brain stimulation in Parkinson's disease patients.

Parkinsonism Relat Disord 2019 05 24;62:91-97. Epub 2019 Jan 24.

Université Pierre et Marie Curie-Paris 6, Centre de Recherche de l'Institut du Cerveau et de la Moelle épiniere (CRICM), UMR-S975, Paris, France; INSERM, U975, Paris, France; CNRS, UMR 7225, CR-ICM, Paris, France; Neurophysiology Department, CHU Rouen, Normandie University, Rouen, France. Electronic address:

Introduction: Freezing of gait (FOG) and falls are the most disabling motor symptoms in Parkinson's disease (PD) patients. The effects of subthalamic deep-brain-stimulation (STN-DBS) on FOG and falls are still a matter of controversy, and factors contributing to their outcome have yet to be defined.

Methods: We examined the relationship between FOG and falls after STN-DBS and preoperative clinical features, MRI voxel-based-morphometry (VBM) analysis and statistical mapping of electrode locations.

Results: 331 patients (age at surgery = 57.7 ± 8.4 years; disease duration = 12.5 ± 5 years) were included in the final analysis, with VBM analysis in 151 patients. After surgery, FOG was aggravated in 93 patients and falls in 75 patients. After surgery, FOG severity was related to its level before surgery without dopaminergic treatment, the dopaminergic treatment dosage and severity of motor fluctuations after surgery; and falls severity to lower postoperative cognitive performance. VBM analyses revealed that, relative to other patient groups, patients with FOG worsening had putamen grey matter density decrease, and fallers patients a left postcentral gyrus atrophy. The best effects of STN-DBS on FOG and falls were associated with the location of contacts within the STN, but no specific location related to aggravation.

Conclusions: FOG and falls are reduced after STN-DBS in about 1/3 of patients, with the best effects obtained for electrodes located within the STN. Clinicians should be aware that, after STN-DBS, FOG severity is related to preoperative FOG severity whatever its dopa-sensitivity; and falls to lower postoperative cognitive performance; and atrophy of cortico-subcortical brain areas.
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http://dx.doi.org/10.1016/j.parkreldis.2019.01.021DOI Listing
May 2019

Suggestive association between OPRM1 and impulse control disorders in Parkinson's disease.

Mov Disord 2018 12 16;33(12):1878-1886. Epub 2018 Nov 16.

Assistance Publique Hôpitaux de Paris, CHU Pitié-Salpêtrière, Pharmacie, Paris, France.

Background: Impulse control disorders are frequently associated with dopaminergic therapy in Parkinson's disease. Genetic studies have suggested a high heritability of impulse control disorders in the general population and in PD. The aim of this study was to identify candidate gene variants associated with impulse control disorders and related behaviors in PD.

Methods: We performed a multicenter case-control study in PD patients with (cases) or without impulse control disorders and related behaviors despite significant dopamine agonist exposure of >300 mg levodopa-equivalent daily dose during 12 months (controls). Behavioral disorders were assessed using the Ardouin scale. We investigated 50 variants in 24 candidate genes by a multivariate logistic regression analysis adjusted for sex and age at PD onset.

Results: The analysis was performed on 172 cases and 132 controls. Cases were younger (60 ± 8 vs 63 ± 8 years; P < 0.001) and had a higher family history of pathological gambling (12% vs 5%, P = 0.03). No variant was significantly associated with impulse control disorders or related behaviors after correction for multiple testing, although the 2 top variants were close to significant (OPRM1 rs179991, OR, 0.49; 95%CI, 0.32-0.76; P = 0.0013; Bonferroni adjusted P = 0.065; DAT1 40-base pair variable number tandem repeat, OR, 1.82; 95%CI, 1.24-2.68; P = 0.0021; Bonferroni adjusted P = 0.105).

Conclusions: Our results are suggestive of a novel association of the opioid receptor gene OPRM1 with impulse control disorders and related behaviors in PD and confirm a previous association with DAT1. Although replication in independent studies is needed, our results bring potential new insights to the understanding of molecular mechanisms of impulse control disorders. © 2018 International Parkinson and Movement Disorder Society.
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http://dx.doi.org/10.1002/mds.27519DOI Listing
December 2018

Naftazone in advanced Parkinson's disease: An acute L-DOPA challenge randomized controlled trial.

Parkinsonism Relat Disord 2019 03 4;60:51-56. Epub 2018 Oct 4.

Clinical Investigation Center CIC-1436, Departments of Clinical Pharmacology and Neurosciences, University Hospital of Toulouse, INSERM, University of Toulouse 3, Toulouse, France; F-CRIN, UMS 015, Toulouse, France.

Introduction: There is an unmet need to better control motor complications in Parkinson's disease (PD). Naftazone, which exhibits glutamate release inhibition properties, has shown antiparkinsonian and antidyskinetic activity in preclinical models of PD and in a clinical proof of concept study.

Methods: We conducted a double-blind randomized placebo-controlled cross-over trial in PD patients with motor fluctuations and dyskinesia testing naftazone 160 mg/day versus placebo for 14 days. The two co-primary endpoints were the area under curve (AUC) of motor (MDS-UPDRS part III) and dyskinesia (AIMS) scores during an acute levodopa challenge performed at the end of each period. Secondary endpoints were UDysRS and axial symptoms scores during the challenge; AIMS, UDysRS, and time spent with or without dyskinesia the day before the challenge. The primary analysis was performed in the per protocol population.

Results: Sixteen patients were included in the analysis. There was no difference between naftazone and placebo for the AUC of MDS-UPDRS III (-89, 95%CI[-1071; 893], p = 0.85), and AIMS (70, 95%CI[-192; 332], p = 0.57). At the end of treatment periods, AIMS score tended to be lower with naftazone than placebo (4.4 ± 3.4 versus 6.7 ± 4.4, p = 0.07), but UDysRS scores and other secondary outcomes were not different. Naftazone was safe and well tolerated.

Conclusions: This study did not confirm previous results on the efficacy of naftazone on dyskinesia nor motor fluctuations highlighting the problem of translating results obtained in preclinical models into clinical trials. Further investigation of naftazone may be conducted in PD with longer treatment duration.
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http://dx.doi.org/10.1016/j.parkreldis.2018.10.005DOI Listing
March 2019

Longitudinal analysis of impulse control disorders in Parkinson disease.

Neurology 2018 07 20;91(3):e189-e201. Epub 2018 Jun 20.

From the Assistance Publique Hôpitaux de Paris (J.-C.C., F.C.-D., L.L., C.B., D.G., S.K., G.M., H.Y., A.B., M.V.); Sorbonne Université (J.-C.C., F.C.-D., L.L., C.B., D.G., S.K., G.M., H.Y., A.B., M.V.); INSERM (J.-C.C., F.C.-D., L.L., C.B., D.G., S.K., G.M., H.Y., A.B., M.V.), Institut du cerveau et de la Moelle, Centre d'Investigation Clinique Neurosciences, NS-PARK/FCRIN Network; CNRS (J.-C.C., F.C.-D., L.L., C.B., D.G., S.K., G.M., H.Y., A.B., M.V.); Departments of Neurology and Genetics (J.-C.C., F.C.-D., L.L., C.B., D.G., S.K., G.M., H.Y., A.B., M.V.), Hôpital Pitié-Salpêtrière, Paris; CESP (F.A., A.E.), Faculte de médecine, Université Paris-Sud; Faculte de médecine (F.A., A.E.), UVSQ, Institut National de la Santé et de la Recherche Médicale, Université Paris-Saclay, Villejuif; University of Toulouse 3 (O.R., C.B.-C., F.O.-M), Centre Hospitalo-Universitaire de Toulouse and INSERM; Centre d'Investigation Clinique CIC1436 (O.R., C.B.-C., F.O.-M), NS-PARK/FCRIN Network, Départements de Neurosciences et de Pharmacologie Clinique, NeuroToul COEN Center, Toulouse; Department of Neurology (F.D., A.-R.M.), NS-PARK/FCRIN Network, Centre Hospitalo-Universitaire de Clermont-Ferrand; Department of Neurology (P.D.), NS-PARK/FCRIN Network, Centre Hospitalo-Universitaire de Nantes; Department of Neurology (F.B.), Hôpital Foch, Suresnes; Department of Neurology (J.-P.B.), Fondation Rothschild, Paris; Department of Neurology (F.P.), Centre Hospitalier de Versailles; Université Versailles Saint Quentin en Yvelines et Paris Saclay (F.P.), Versailles; Department of Neurology (V.M.), Centre Hospitalo-Universitaire Saint-Antoine, Paris, France; and Department of Health Care Management (P.-C.L.), College of Health Technology, National Taipei University of Nursing and Health Sciences, Taiwan.

Objective: To investigate the longitudinal dose-effect relationship between dopamine replacement therapy and impulse control disorders (ICDs) in Parkinson disease (PD).

Methods: We used data from a multicenter longitudinal cohort of consecutive patients with PD with ≤5 years' disease duration at baseline followed up annually up to 5 years. ICDs were evaluated during face-to-face semistructured interviews with movement disorder specialists. Generalized estimating equations and Poisson models with robust variance were used to study the association between several time-dependent definitions of dopamine agonist (DA) use, taking dose and duration of treatment into account, and ICDs at each visit. Other antiparkinsonian drugs were also examined.

Results: Among 411 patients (40.6% women, mean age 62.3 years, average follow-up 3.3 years, SD 1.7 years), 356 (86.6%) took a DA at least once since disease onset. In 306 patients without ICDs at baseline, the 5-year cumulative incidence of ICDs was 46.1% (95% confidence interval [CI] 37.4-55.7, DA ever users 51.5% [95% CI 41.8-62.1], DA never users 12.4% [95% CI 4.8-30.0]). ICD prevalence increased from 19.7% at baseline to 32.8% after 5 years. ICDs were associated with ever DA use (prevalence ratio 4.23, 95% CI 1.78-10.09). Lifetime average daily dose and duration of treatment were independently associated with ICDs with significant dose-effect relationships. Similar analyses for levodopa were not in favor of a strong association. ICDs progressively resolved after DA discontinuation.

Conclusion: In this longitudinal study of patients with PD characterized by a high prevalence of DA treatment, the 5-year cumulative incidence of ICDs was ≈46%. ICDs were strongly associated with DA use with a dose-effect relationship; both increasing duration and dose were associated with ICDs. ICDs progressively resolved after DA discontinuation.

Clinicaltrialsgov Identifier: NCT01564992.
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http://dx.doi.org/10.1212/WNL.0000000000005816DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6059034PMC
July 2018

Sleep and REM sleep behaviour disorder in Parkinson's disease with impulse control disorder.

J Neurol Neurosurg Psychiatry 2018 03 24;89(3):305-310. Epub 2017 Oct 24.

EA7820 UFR Medecine, Universite Clermont Auvergne, Clermont-Ferrand, France.

Introduction: Because the association between rapid eye movement sleep behaviour disorder (RBD) and impulse control disorders (ICDs) in Parkinson's disease (PD) has been debated, we assessed the sleep characteristics and the frequency of RBD using video-polysomnography (v-PSG) in patients with PD with versus without ICDs.

Methods: Eighty non-demented patients with PD consecutively identified during routine evaluation at three movement disorders centres were enrolled in a case-control study. Forty patients (22 men; mean age: 62.6±9.7 years, Hoehn & Yahr: 2.1±0.6) with one or more current ICDs were age-matched and sex-matched with 40 patients with no history of ICDs (22 men, mean age: 64.9±7.8 years, Hoehn & Yahr: 2.2±0.6). They underwent a detailed sleep interview followed by a full-night in-lab v-PSG. Sleep was scored blindly to ICDs condition and RBD diagnosis included a clinical complaint of enacted dreams and/or documented behaviour during rapid eye movement (REM) sleep, with the presence of quantified REM sleep without atonia (RSWA).

Results: Patients with ICDs had a higher arousal index and higher RSWA than those without ICDs (51.9%±28.2%vs 32.2±27.1%, p=0.004). In addition, RBD was more frequent in the ICD group (85%vs53%, p=0.0001). RBD was still associated with ICDs in a multivariate regression analysis including age of onset, PD duration and severity, treatment duration, levodopa-equivalent and dopamine agonist-equivalent daily doses and antidepressant use (OR: 4.9 (95% CI 1.3 to 18.5), p=0.02).

Conclusions: This large, controlled series of patients with PD with ICDs assessed by v-PSG confirms the association between ICDs and RBD. Increased surveillance of symptoms of ICDs should be recommended in patients with PD with RBD.
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http://dx.doi.org/10.1136/jnnp-2017-316576DOI Listing
March 2018

Prediction of cognition in Parkinson's disease with a clinical-genetic score: a longitudinal analysis of nine cohorts.

Lancet Neurol 2017 08 16;16(8):620-629. Epub 2017 Jun 16.

Neurogenomics Laboratory and Parkinson Personalized Medicine Program of Harvard Medical School and Brigham and Women's Hospital, Boston, MA, USA; Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital, Boston, MA, USA; Department of Neurology, Brigham and Women's Hospital, Boston, MA, USA; Department of Neurology, Massachusetts General Hospital, Boston, MA, USA; Biomarkers Program, Harvard NeuroDiscovery Center, Boston, MA, USA. Electronic address:

Background: Cognitive decline is a debilitating manifestation of disease progression in Parkinson's disease. We aimed to develop a clinical-genetic score to predict global cognitive impairment in patients with the disease.

Methods: In this longitudinal analysis, we built a prediction algorithm for global cognitive impairment (defined as Mini Mental State Examination [MMSE] ≤25) using data from nine cohorts of patients with Parkinson's disease from North America and Europe assessed between 1986 and 2016. Candidate predictors of cognitive decline were selected through a backward eliminated Cox's proportional hazards analysis using the Akaike's information criterion. These were used to compute the multivariable predictor on the basis of data from six cohorts included in a discovery population. Independent replication was attained in patients from a further three independent longitudinal cohorts. The predictive score was rebuilt and retested in 10 000 training and test sets randomly generated from the entire study population.

Findings: 3200 patients with Parkinson's disease who were longitudinally assessed with 27 022 study visits between 1986 and 2016 in nine cohorts from North America and Europe were assessed for eligibility. 235 patients with MMSE ≤25 at baseline and 135 whose first study visit occurred more than 12 years from disease onset were excluded. The discovery population comprised 1350 patients (after further exclusion of 334 with missing covariates) from six longitudinal cohorts with 5165 longitudinal visits over 12·8 years (median 2·8, IQR 1·6-4·6). Age at onset, baseline MMSE, years of education, motor exam score, sex, depression, and β-glucocerebrosidase (GBA) mutation status were included in the prediction model. The replication population comprised 1132 patients (further excluding 14 patients with missing covariates) from three longitudinal cohorts with 19 127 follow-up visits over 8·6 years (median 6·5, IQR 4·1-7·2). The cognitive risk score predicted cognitive impairment within 10 years of disease onset with an area under the curve (AUC) of more than 0·85 in both the discovery (95% CI 0·82-0·90) and replication (95% CI 0·78-0·91) populations. Patients scoring in the highest quartile for cognitive risk score had an increased hazard for global cognitive impairment compared with those in the lowest quartile (hazard ratio 18·4 [95% CI 9·4-36·1]). Dementia or disabling cognitive impairment was predicted with an AUC of 0·88 (95% CI 0·79-0·94) and a negative predictive value of 0·92 (95% 0·88-0·95) at the predefined cutoff of 0·196. Performance was stable in 10 000 randomly resampled subsets.

Interpretation: Our predictive algorithm provides a potential test for future cognitive health or impairment in patients with Parkinson's disease. This model could improve trials of cognitive interventions and inform on prognosis.

Funding: National Institutes of Health, US Department of Defense.
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http://dx.doi.org/10.1016/S1474-4422(17)30122-9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5761650PMC
August 2017

Specifically neuropathic Gaucher's mutations accelerate cognitive decline in Parkinson's.

Ann Neurol 2016 Nov;80(5):674-685

Neurogenomics Lab and Parkinson Personalized Medicine Program, Harvard Medical School and Brigham & Women's Hospital, Cambridge, MA.

Objective: We hypothesized that specific mutations in the β-glucocerebrosidase gene (GBA) causing neuropathic Gaucher's disease (GD) in homozygotes lead to aggressive cognitive decline in heterozygous Parkinson's disease (PD) patients, whereas non-neuropathic GD mutations confer intermediate progression rates.

Methods: A total of 2,304 patients with PD and 20,868 longitudinal visits for up to 12.8 years (median, 4.1) from seven cohorts were analyzed. Differential effects of four types of genetic variation in GBA on longitudinal cognitive decline were evaluated using mixed random and fixed effects and Cox proportional hazards models.

Results: Overall, 10.3% of patients with PD and GBA sequencing carried a mutation. Carriers of neuropathic GD mutations (1.4% of patients) had hazard ratios (HRs) for global cognitive impairment of 3.17 (95% confidence interval [CI], 1.60-6.25) and a hastened decline in Mini-Mental State Exam scores compared to noncarriers (p = 0.0009). Carriers of complex GBA alleles (0.7%) had an HR of 3.22 (95% CI, 1.18-8.73; p = 0.022). By contrast, the common, non-neuropathic N370S mutation (1.5% of patients; HR, 1.96; 95% CI, 0.92-4.18) or nonpathogenic risk variants (6.6% of patients; HR, 1.36; 95% CI, 0.89-2.05) did not reach significance.

Interpretation: Mutations in the GBA gene pathogenic for neuropathic GD and complex alleles shift longitudinal cognitive decline in PD into "high gear." These findings suggest a relationship between specific types of GBA mutations and aggressive cognitive decline and have direct implications for improving the design of clinical trials. Ann Neurol 2016;80:674-685.
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http://dx.doi.org/10.1002/ana.24781DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5244667PMC
November 2016

Clinical-genetic model predicts incident impulse control disorders in Parkinson's disease.

J Neurol Neurosurg Psychiatry 2016 Oct 13;87(10):1106-11. Epub 2016 Apr 13.

Sorbonne Universités, UPMC Univ Paris 06, and INSERM UMRS_1127 and CIC_1422, and CNRS UMR_7225, and AP-HP, and ICM, Département des maladies du système nerveux and Département de Génétique, Hôpital Pitié-Salpêtrière, Paris, France.

Objectives: Impulse control disorders (ICD) are commonly associated with dopamine replacement therapy (DRT) in patients with Parkinson's disease (PD). Our aims were to estimate ICD heritability and to predict ICD by a candidate genetic multivariable panel in patients with PD.

Methods: Data from de novo patients with PD, drug-naïve and free of ICD behaviour at baseline, were obtained from the Parkinson's Progression Markers Initiative cohort. Incident ICD behaviour was defined as positive score on the Questionnaire for Impulsive-Compulsive Disorders in PD. ICD heritability was estimated by restricted maximum likelihood analysis on whole exome sequencing data. 13 candidate variants were selected from the DRD2, DRD3, DAT1, COMT, DDC, GRIN2B, ADRA2C, SERT, TPH2, HTR2A, OPRK1 and OPRM1 genes. ICD prediction was evaluated by the area under the curve (AUC) of receiver operating characteristic (ROC) curves.

Results: Among 276 patients with PD included in the analysis, 86% started DRT, 40% were on dopamine agonists (DA), 19% reported incident ICD behaviour during follow-up. We found heritability of this symptom to be 57%. Adding genotypes from the 13 candidate variants significantly increased ICD predictability (AUC=76%, 95% CI (70% to 83%)) compared to prediction based on clinical variables only (AUC=65%, 95% CI (58% to 73%), p=0.002). The clinical-genetic prediction model reached highest accuracy in patients initiating DA therapy (AUC=87%, 95% CI (80% to 93%)). OPRK1, HTR2A and DDC genotypes were the strongest genetic predictive factors.

Conclusions: Our results show that adding a candidate genetic panel increases ICD predictability, suggesting potential for developing clinical-genetic models to identify patients with PD at increased risk of ICD development and guide DRT management.
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http://dx.doi.org/10.1136/jnnp-2015-312848DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5098340PMC
October 2016

Loss-of-function mutations in RAB39B are associated with typical early-onset Parkinson disease.

Neurol Genet 2015 Jun 18;1(1):e9. Epub 2015 Jun 18.

Institut du Cerveau et de la Moelle épinière, ICM, Inserm U 1127, CNRS, UMR 7225, Sorbonne Universités, UPMC University Paris 06 UMR S 1127 (S.L., F.C.-D., C.C., A.N., A.B.), Paris, France; Centre d'Investigation Clinique Pitié Neurosciences CIC-1422 (F.C.-D.); AP-HP, Hôpital de la Salpêtrière (A.B.), Department of Genetics and Cytogenetics, Paris, France; Department of Molecular Neuroscience (J.B., L.D., R.G., M.F., N.W., J.H.), UCL Institute of Neurology, London, United Kingdom; Laboratory of Neurogenetics (E.M., M.F., A.S.), National Institute on Aging, Bethesda, MD; Hertie Institute for Clinical Brain Research (P.H., T.G.), University of Tübingen and DZNE (P.H., T.G.), German Center for Neurodegenerative Diseases, Tübingen, Germany; and Institut des Maladies Neurodégénératives (F.T.), Université de Bordeaux et CHU de Bordeaux, Bordeaux, France.

Rab proteins are small molecular weight guanosine triphosphatases involved in the regulation of vesicular trafficking.(1) Three of 4 X-linked RAB genes are specific to the brain, including RAB39B. Recently, Wilson et al.(2) reported that mutations in RAB39B cause X-linked intellectual disability (ID) and pathologically confirmed Parkinson disease (PD). They identified a ∼45-kb deletion resulting in the complete loss of RAB39B in an Australian kindred and a missense mutation in a large Wisconsin kindred. Here, we report an additional affected man with typical PD and mild mental retardation harboring a new truncating mutation in RAB39B.
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http://dx.doi.org/10.1212/NXG.0000000000000009DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4821081PMC
June 2015

Loss of VPS13C Function in Autosomal-Recessive Parkinsonism Causes Mitochondrial Dysfunction and Increases PINK1/Parkin-Dependent Mitophagy.

Am J Hum Genet 2016 Mar;98(3):500-513

Laboratory of Neurogenetics, National Institute on Aging, NIH, Bethesda, MD 20892, USA.

Autosomal-recessive early-onset parkinsonism is clinically and genetically heterogeneous. The genetic causes of approximately 50% of autosomal-recessive early-onset forms of Parkinson disease (PD) remain to be elucidated. Homozygozity mapping and exome sequencing in 62 isolated individuals with early-onset parkinsonism and confirmed consanguinity followed by data mining in the exomes of 1,348 PD-affected individuals identified, in three isolated subjects, homozygous or compound heterozygous truncating mutations in vacuolar protein sorting 13C (VPS13C). VPS13C mutations are associated with a distinct form of early-onset parkinsonism characterized by rapid and severe disease progression and early cognitive decline; the pathological features were striking and reminiscent of diffuse Lewy body disease. In cell models, VPS13C partly localized to the outer membrane of mitochondria. Silencing of VPS13C was associated with lower mitochondrial membrane potential, mitochondrial fragmentation, increased respiration rates, exacerbated PINK1/Parkin-dependent mitophagy, and transcriptional upregulation of PARK2 in response to mitochondrial damage. This work suggests that loss of function of VPS13C is a cause of autosomal-recessive early-onset parkinsonism with a distinctive phenotype of rapid and severe progression.
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http://dx.doi.org/10.1016/j.ajhg.2016.01.014DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4800038PMC
March 2016

High nigral iron deposition in LRRK2 and Parkin mutation carriers using R2* relaxometry.

Mov Disord 2015 Jul 22;30(8):1077-84. Epub 2015 May 22.

Institut du Cerveau et de la Moelle épinière-ICM, Centre de NeuroImagerie de Recherche-CENIR, Paris, France.

Objectives: The goal of this work was to investigate iron deposition in the basal ganglia and thalamus in symptomatic and asymptomatic leucine-rich repeat kinase 2 (LRRK2) and Parkin-associated Parkinson's disease (PD), using R2* relaxometry rate.

Methods: Twenty subjects with genetic PD (four symptomatic and two asymptomatic Parkin subjects, nine symptomatic and five asymptomatic LRRK2 subjects) were compared with 20 patients with idiopathic PD (IPD) and 20 healthy subjects. Images were obtained at 3 teslas, using multi-echo T2 and T2* sequences. R2 and R2* values were calculated in the substantia nigra (SN), the striatum, the globus pallidus, and the thalamus.

Results: The R2* values in the SN were increased in IPD and mutation-carrying patients as compared with controls and in mutation-carrying patients as compared with IPD. Asymptomatic mutation carriers showed higher R2* values than controls and did not differ from IPD patients. No changes were seen in the other structures or in R2 values.

Conclusion: These results are consistent with increased iron load in LRRK2- and Parkin-mutation carriers. The increased R2* in asymptomatic PD-mutation carriers suggests that iron deposition occurs early during the preclinical phase of the disease. R2* measurements may be used as markers for investigating nigrostriatal damage in preclinical mutation-carrying patients.
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http://dx.doi.org/10.1002/mds.26218DOI Listing
July 2015

Dopaminergic denervation severity depends on COMT Val158Met polymorphism in Parkinson's disease.

Parkinsonism Relat Disord 2015 May 19;21(5):471-6. Epub 2015 Feb 19.

Sorbonne University, UPMC Paris 06 UMR S 1127, and Inserm U 1127 and CIC 1422, and CNRS UR 7225, and ICM, 75013 Paris, France; AP-HP, Department of Neurology, Pitié-Salpêtrière Hospital, 75013 Paris, France. Electronic address:

Background: Catecholamine-O-methyl-tranferase (COMT) initiates dopamine degradation. Its activity is mainly determined by a single nucleotide polymorphism in the COMT gene (Val158Met, rs4680) separating high (Val/Val, COMT(HH)), intermediate (Val/Met, COMT(HL)) and low metabolizers (Met/Met, COMT(LL)). We investigated dopaminergic denervation in the striatum in PD patients according to COMT rs4680 genotype.

Methods: Patients with idiopathic PD were assessed for motor severity (UPDRS-III rating scale in OFF-state), dopaminergic denervation using [123I]-FP-CIT SPECT imaging, and genotyped for the COMT rs4680 enzyme. [123I]-FP-CIT binding potential (BP) for each voxel was defined by the ratio of tracer-binding in the region of interest (striatum, caudate nucleus and putamen) to that in a region of non-specific activity. Genotyping was performed using TaqMan(®) SNP genotyping assay. We used a regression model to evaluate the effect of COMT genotype on the BP in the striatum and its sub-regions.

Results: Genotype distribution was: 11 (27.5%) COMT(HH), 26 (65%) COMT(HL) and 3 (7.5%) COMT(LL). There were no significant differences in disease severity, treatments, or motor scores between genotypes. When adjusted to clinical severity, gender and age, low and intermediate metabolizers showed significantly higher rates of striatal denervation (COMT(HL+LL) BP = 1.32 ± 0.04) than high metabolizers (COMT(HH), BP = 1.6 ± 0.08; F(1.34) = 9.0, p = 0.005). Striatal sub-regions showed similar results. BP and UPDRS-III motor scores (r = 0.44, p = 0.04) (p < 0.001) were highly correlated. There was a gender effect, but no gender-genotype interaction.

Conclusions: Striatal denervation differs according to COMT-Val158Met polymorphism. COMT activity may play a role as a compensatory mechanism in PD motor symptoms.
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http://dx.doi.org/10.1016/j.parkreldis.2015.02.009DOI Listing
May 2015

Parkinson's disease in GTP cyclohydrolase 1 mutation carriers.

Brain 2014 Sep 2;137(Pt 9):2480-92. Epub 2014 Jul 2.

19 Université Pierre et Marie Curie-Paris6, Centre de Recherche de l'Institut du Cerveau et de la Moelle épinière, UMR-S975; Inserm, U975, Cnrs, UMR 7225, Paris, France20 Centre d'Investigation Clinique (CIC-9503), Département de Neurologie, Hôpital Pitié-Salpétriêre, AP-HP, Paris, France.

GTP cyclohydrolase 1, encoded by the GCH1 gene, is an essential enzyme for dopamine production in nigrostriatal cells. Loss-of-function mutations in GCH1 result in severe reduction of dopamine synthesis in nigrostriatal cells and are the most common cause of DOPA-responsive dystonia, a rare disease that classically presents in childhood with generalized dystonia and a dramatic long-lasting response to levodopa. We describe clinical, genetic and nigrostriatal dopaminergic imaging ([(123)I]N-ω-fluoropropyl-2β-carbomethoxy-3β-(4-iodophenyl) tropane single photon computed tomography) findings of four unrelated pedigrees with DOPA-responsive dystonia in which pathogenic GCH1 variants were identified in family members with adult-onset parkinsonism. Dopamine transporter imaging was abnormal in all parkinsonian patients, indicating Parkinson's disease-like nigrostriatal dopaminergic denervation. We subsequently explored the possibility that pathogenic GCH1 variants could contribute to the risk of developing Parkinson's disease, even in the absence of a family history for DOPA-responsive dystonia. The frequency of GCH1 variants was evaluated in whole-exome sequencing data of 1318 cases with Parkinson's disease and 5935 control subjects. Combining cases and controls, we identified a total of 11 different heterozygous GCH1 variants, all at low frequency. This list includes four pathogenic variants previously associated with DOPA-responsive dystonia (Q110X, V204I, K224R and M230I) and seven of undetermined clinical relevance (Q110E, T112A, A120S, D134G, I154V, R198Q and G217V). The frequency of GCH1 variants was significantly higher (Fisher's exact test P-value 0.0001) in cases (10/1318 = 0.75%) than in controls (6/5935 = 0.1%; odds ratio 7.5; 95% confidence interval 2.4-25.3). Our results show that rare GCH1 variants are associated with an increased risk for Parkinson's disease. These findings expand the clinical and biological relevance of GTP cycloydrolase 1 deficiency, suggesting that it not only leads to biochemical striatal dopamine depletion and DOPA-responsive dystonia, but also predisposes to nigrostriatal cell loss. Further insight into GCH1-associated pathogenetic mechanisms will shed light on the role of dopamine metabolism in nigral degeneration and Parkinson's disease.
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http://dx.doi.org/10.1093/brain/awu179DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4132650PMC
September 2014

The autophagy/lysosome pathway is impaired in SCA7 patients and SCA7 knock-in mice.

Acta Neuropathol 2014 Nov 24;128(5):705-22. Epub 2014 May 24.

Sorbonne Universités, UPMC Univ. Paris 6, ICM, 75013, Paris, France,

There is still no treatment for polyglutamine disorders, but clearance of mutant proteins might represent a potential therapeutic strategy. Autophagy, the major pathway for organelle and protein turnover, has been implicated in these diseases. To determine whether the autophagy/lysosome system contributes to the pathogenesis of spinocerebellar ataxia type 7 (SCA7), caused by expansion of a polyglutamine tract in the ataxin-7 protein, we looked for biochemical, histological and transcriptomic abnormalities in components of the autophagy/lysosome pathway in a knock-in mouse model of the disease, postmortem brain and peripheral blood mononuclear cells (PBMC) from patients. In the mouse model, mutant ataxin-7 accumulated in inclusions immunoreactive for the autophagy-associated proteins mTOR, beclin-1, p62 and ubiquitin. Atypical accumulations of the autophagosome/lysosome markers LC3, LAMP-1, LAMP2 and cathepsin-D were also found in the cerebellum of the SCA7 knock-in mice. In patients, abnormal accumulations of autophagy markers were detected in the cerebellum and cerebral cortex of patients, but not in the striatum that is spared in SCA7, suggesting that autophagy might be impaired by the selective accumulation of mutant ataxin-7. In vitro studies demonstrated that the autophagic flux was impaired in cells overexpressing full-length mutant ataxin-7. Interestingly, the expression of the early autophagy-associated gene ATG12 was increased in PBMC from SCA7 patients in correlation with disease severity. These results provide evidence that the autophagy/lysosome pathway is impaired in neurons undergoing degeneration in SCA7. Autophagy/lysosome-associated molecules might, therefore, be useful markers for monitoring the effects of potential therapeutic approaches using modulators of autophagy in SCA7 and other autophagy/lysosome-associated neurodegenerative disorders.
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http://dx.doi.org/10.1007/s00401-014-1289-8DOI Listing
November 2014

Dopa-decarboxylase gene polymorphisms affect the motor response to L-dopa in Parkinson's disease.

Parkinsonism Relat Disord 2014 Feb 24;20(2):170-5. Epub 2013 Oct 24.

INSERM (French National Institute of Medical Research and Health), APHP (Assistance Publique Hopitaux de Paris), Clinical Investigation Center (CIC-9503), Pitié-Salpêtrière Hospital, Paris, France; INSERM, UMRS_975 unit, UPMC (Pierre and Marie Curie University), CNRS UMR7525 CR-ICM, Paris, France; APHP, Pitié-Salpêtrière Hospital, Department of Neurology, France.

Background: In Parkinson's disease (PD), the response to L-dopa is highly variable and unpredictable. The major pathway for dopamine synthesis from L-dopa is decarboxylation by aromatic L-amino acid decarboxylase (AAAD, encoded by the DDC gene).

Objective: To determine the motor response to L-dopa in PD patients as a function of the DDC gene promoter polymorphisms (rs921451 T > C polymorphism (DDC(T/C)) and rs3837091 AGAG del (DDC(AGAG/-))).

Methods: Thirty-three Caucasian PD patients underwent an acute l-dopa challenge together with the peripheral AAAD inhibitor benserazide and were genotyped for rs921451 and rs3837091. The primary efficacy criterion was the motor response to L-dopa, as estimated by the area under the curve for the change in the Unified Parkinson's Disease Rating Scale part III (UPDRS) score relative to baseline (AUCΔUPDRS) in the 4 h following L-dopa administration. Secondary endpoints were pharmacokinetic parameters for plasma levels of L-dopa and dopamine. Investigators and patients were blinded to genotypes data throughout the study.

Results: When adjusted for the L-dopa dose, the AUCΔUPDRS was significantly lower in DDC(CC/CT) patients (n = 14) than in DDC(TT) patients (n = 19) and significantly lower in DDC(-/- or AGAG/-) patients (n = 8) than in DDC(AGAG/AGAG) patients (n = 25). There were no significant intergroup differences in plasma pharmacokinetic parameters for L-dopa and dopamine.

Discussion: The rs921451 and rs3837091 polymorphisms of the DDC gene promoter influence the motor response to L-dopa but do not significantly change peripheral pharmacokinetic parameters for L-dopa and dopamine. Our results suggest that DDC may be a genetic modifier of the l-dopa response in Parkinson's disease.
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http://dx.doi.org/10.1016/j.parkreldis.2013.10.017DOI Listing
February 2014
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