References of "Vaillant, Michel"
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See detailThe Luxembourg Parkinson’s Study: A Comprehensive Approach for Stratification and Early Diagnosis
Hipp Epouse D'amico, Géraldine UL; Vaillant, Michel; Diederich, Nico J. et al

in Frontiers in Aging Neuroscience (2018), 10

While genetic advances have successfully defined part of the complexity in Parkinson’s disease (PD), the clinical characterization of phenotypes remains challenging. Therapeutic trials and cohort studies ... [more ▼]

While genetic advances have successfully defined part of the complexity in Parkinson’s disease (PD), the clinical characterization of phenotypes remains challenging. Therapeutic trials and cohort studies typically include patients with earlier disease stages and exclude comorbidities, thus ignoring a substantial part of the real-world PD population. To account for these limitations, we implemented the Luxembourg PD study as a comprehensive clinical, molecular and device-based approach including patients with typical PD and atypical parkinsonism, irrespective of their disease stage, age, comorbidities, or linguistic background. To provide a large, longitudinally followed, and deeply phenotyped set of patients and controls for clinical and fundamental research on PD, we implemented an open-source digital platform that can be harmonized with international PD cohort studies. Our interests also reflect Luxembourg-specific areas of PD research, including vision, gait, and cognition. This effort is flanked by comprehensive biosampling efforts assuring high quality and sustained availability of body liquids and tissue biopsies. We provide evidence for the feasibility of such a cohort program with deep phenotyping and high quality biosampling on parkinsonism in an environment with structural specificities and alert the international research community to our willingness to collaborate with other centers. The combination of advanced clinical phenotyping approaches including device-based assessment will create a comprehensive assessment of the disease and its variants, its interaction with comorbidities and its progression. We envision the Luxembourg Parkinson’s study as an important research platform for defining early diagnosis and progression markers that translate into stratified treatment approaches. [less ▲]

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See detailAdding anthropometric measures of regional adiposity to BMI improves prediction of cardiometabolic, inflammatory and adipokines profiles in youths: a cross-sectional study.
Samouda, Hanen; De Beaufort, Carine UL; Stranges, Saverio et al

in BMC pediatrics (2015), 15

BACKGROUND: Paediatric research analysing the relationship between the easy-to-use anthropometric measures for adiposity and cardiometabolic risk factors remains highly controversial in youth. Several ... [more ▼]

BACKGROUND: Paediatric research analysing the relationship between the easy-to-use anthropometric measures for adiposity and cardiometabolic risk factors remains highly controversial in youth. Several studies suggest that only body mass index (BMI), a measure of relative weight, constitutes an accurate predictor, whereas others highlight the potential role of waist-to-hip ratio (WHR), waist circumference (Waist C), and waist-to-height ratio (WHtR). In this study, we examined the effectiveness of adding anthropometric measures of body fat distribution (Waist C Z Score, WHR Z Score and/or WHtR) to BMI Z Score to predict cardiometabolic risk factors in overweight and obese youth. We also examined the consistency of these associations with the "total fat mass + trunk/legs fat mass" and/or the "total fat mass + trunk fat mass" combinations, as assessed by dual energy X-ray absorptiometry (DXA), the gold standard measurement of body composition. METHODS: Anthropometric and DXA measurements of total and regional adiposity, as well as a comprehensive assessment of cardiometabolic, inflammatory and adipokines profiles were performed in 203 overweight and obese 7-17 year-old youths from the Paediatrics Clinic, Centre Hospitalier de Luxembourg. RESULTS: Adding only one anthropometric surrogate of regional fat to BMI Z Score improved the prediction of insulin resistance (WHR Z Score, R(2): 45.9%. Waist C Z Score, R(2): 45.5%), HDL-cholesterol (WHR Z Score, R(2): 9.6%. Waist C Z Score, R(2): 10.8%. WHtR, R(2): 6.5%), triglycerides (WHR Z Score, R(2): 11.7%. Waist C Z Score, R(2): 12.2%), adiponectin (WHR Z Score, R(2): 14.3%. Waist C Z Score, R(2): 17.7%), CRP (WHR Z Score, R(2): 18.2%. WHtR, R(2): 23.3%), systolic (WHtR, R(2): 22.4%), diastolic blood pressure (WHtR, R(2): 20%) and fibrinogen (WHtR, R(2): 21.8%). Moreover, WHR Z Score, Waist C Z Score and/or WHtR showed an independent significant contribution according to these models. These results were in line with the DXA findings. CONCLUSIONS: Adding anthropometric measures of regional adiposity to BMI Z Score improves the prediction of cardiometabolic, inflammatory and adipokines profiles in youth. [less ▲]

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See detailCardiometabolic risk: leg fat is protective during childhood.
Samouda, Hanen; De Beaufort, Carine UL; Stranges, Saverio et al

in Pediatric diabetes (2015)

BACKGROUND: Childhood obesity is associated with early cardiometabolic risk (CMR), increased risk of adulthood obesity, and worse health outcomes. Leg fat mass (LFM) is protective beyond total fat mass ... [more ▼]

BACKGROUND: Childhood obesity is associated with early cardiometabolic risk (CMR), increased risk of adulthood obesity, and worse health outcomes. Leg fat mass (LFM) is protective beyond total fat mass (TFM) in adults. However, the limited evidence in children remains controversial. OBJECTIVE: We investigated the relationship between LFM and CMR factors in youth. SUBJECTS: A total of 203 overweight/obese children, 7-17-yr-old, followed in the Pediatric Clinic, Luxembourg. METHODS: TFM and LFM by dual energy x-ray absorptiometry and a detailed set of CMR markers were analyzed. RESULTS: After TFM, age, sex, body mass index (BMI) Z-score, sexual maturity status, and physical activity adjustments, negative significant partial correlations were shown between LFM and homeostasis model assessment of insulin resistance (HOMA) (variance explained: 6.05% by LFM*; 7.18% by TFM**), fasting insulin (variance explained: 5.71% by LFM*; 6.97% by TFM**), triglycerides (variance explained: 3.96% by LFM*; 2.76% by TFM*), systolic blood pressure (variance explained: 2.68% by LFM*; 4.33% by TFM*), C-reactive protein (variance explained: 2.31% by LFM*; 4.28% by TFM*), and resistin (variance explained: 2.16% by LFM*; 3.57% by TFM*). Significant positive partial correlations were observed between LFM and high-density lipoprotein (HDL) cholesterol (variance explained: 4.16% by LFM*) and adiponectin (variance explained: 3.09% by LFM*) (*p-value < 0.05 and **p-value < 0.001). In order to adjust for multiple testing, Benjamini-Hochberg method was applied and the adjusted significance level was determined for each analysis. LFM remained significant in the aforementioned models predicting HOMA, fasting insulin, triglycerides, and HDL cholesterol (Benjamini and Hochberg corrected p-value < 0.01). CONCLUSIONS: LFM is protective against CMR in children, at least in terms of insulin resistance and adverse blood lipid profiles. [less ▲]

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See detailPrimary vision and facial emotion recognition in early Parkinson's disease
Hipp, Géraldine; Diederich, Nico UL; Pieria, Viannina et al

in Journal of the Neurological Sciences (2014), 338

Background: In early stages of idiopathic Parkinson's disease (IPD), lower order vision (LOV) deficits including reduced colour and contrast discrimination have been consistently reported. Data are less ... [more ▼]

Background: In early stages of idiopathic Parkinson's disease (IPD), lower order vision (LOV) deficits including reduced colour and contrast discrimination have been consistently reported. Data are less conclusive concerning higher order vision (HOV) deficits, especially for facial emotion recognition (FER). However, a link between both visual levels has been hypothesized. Objective: To screen for both levels of visual impairment in early IPD. Methods: We prospectively recruited 28 IPD patients with disease duration of 1.4 +/− 0.8 years and 25 healthy controls. LOV was evaluated by Farnsworth-Munsell 100 Hue Test, Vis-Tech and Pelli-Robson test. HOV was examined by the Ekman 60 Faces Test and part A of the Visual Object and Space recognition test. Results: IPD patients performed worse than controls on almost all LOV tests. The most prominent difference was seen for contrast perception at the lowest spatial frequency (p = 0.0002). Concerning FER IPD patients showed reduced recognition of “sadness” (p = 0.01). “Fear” perception was correlated with perception of low contrast sensitivity in IPD patients within the lowest performance quartile. Controls showed a much stronger link between “fear” perception” and low contrast detection. Conclusion: At the early IPD stage there are marked deficits of LOV performances, while HOV performances are still intact, with the exception of reduced recognition of “sadness”. At this stage, IPD patients seem still to compensate the deficient input of low contrast sensitivity, known to be pivotal for appreciation of negative facial emotions and confirmed as such for healthy controls in this study. [less ▲]

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See detailLack of Polysomnographic Non-REM Sleep Changes in Early Parkinson’s Disease
Diederich, Nico UL; Rufra, Olivier; Pieri, Vannina et al

in Movement Disorders : Official Journal of the Movement Disorder Society (2013)

Background: Polysomnography (PSG) data are rare in patients who have early stage idiopathic Parkinson’s disease (IPD). Methods: Thirty-three patients who had IPD with a disease duration 3 years and 37 age ... [more ▼]

Background: Polysomnography (PSG) data are rare in patients who have early stage idiopathic Parkinson’s disease (IPD). Methods: Thirty-three patients who had IPD with a disease duration 3 years and 37 age-matched controls were recruited. PSG analysis was performed on current medication. Results: Patients with IPD had a reduced mean percentage of muscle atonia during rapid eye movement (REM) sleep (80% vs 93%; P < 0.05). Total sleep time, sleep efficiency, indices/hour of arousals, awakenings, apnea/hypopnea, and periodic leg movements were similar in both groups. Age, but not dopaminergic medication, had a negative impact on sleep architecture in patients with IPD. There was no correlation between sleep efficiency assessed by PSG and sleep quality assessed by questionnaire. Conclusions: The results confirmed a reduction in muscle atonia during REM sleep as a characteristic finding in early IPD. However, there were no further disease-inherent or medication-induced changes in sleep architecture. Although sleep disturbances are considered to be an integral part of IPD, PSG cannot yet identify them objectively at an early stage. VC 2013 International Parkinson and Movement Disorder Society [less ▲]

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See detailDiscriminative power of different nonmotor signs in early Parkinson's disease. A case-control study
Diederich, Nico UL; Pieri, Vannina; Hipp, Geraldine et al

in Movement Disorders : Official Journal of the Movement Disorder Society (2010), 25(7), 882-887

The objective of this study was to evaluate the discriminative power of different nonmotor signs for early diagnosis of Parkinson's disease (PD). Thirty patients with PD with <or=3 years of disease ... [more ▼]

The objective of this study was to evaluate the discriminative power of different nonmotor signs for early diagnosis of Parkinson's disease (PD). Thirty patients with PD with <or=3 years of disease duration were compared with 30 healthy controls. Six deficit domains (DD) were defined: hyposmia, sleep abnormalities, dysautonomia, visual deficits, executive dysfunction, and depression. Plotting of Receiver operating characteristic (ROC) curves and exact conditional logistic modeling, followed by manual stepwise descending procedure were used to identify a model for nonmotor signs that detects early PD. Patients with PD and controls did not differ in terms of age, gender, and educational level. Several DD discriminated patients with PD from healthy controls. Visual deficits showed the largest area under the ROC curve (0.83), followed by hyposmia (0.81) and dysautonomia (0.80). When combining the DD visual deficits and dysautonomia, the best residual model was obtained; it maximized both sensitivity and specificity for PD at a level of 0.77. At an early disease stage, several nonmotor domains were already able to discriminate patients with PD from healthy controls. Visual deficits had the best discriminatory power. Being brief and inexpensive, visual tests should be further investigated in larger cohorts as potential screening tool for early PD. [less ▲]

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See detailProgressive sleep 'destructuring' in Parkinson's disease. A polysomnographic study in 46 patients.
Diederich, Nico UL; Vaillant, Michel; Mancuso, Giovanna UL et al

in Sleep medicine (2005), 6(4), 313-8

BACKGROUND: Sleep abnormalities in Parkinson's disease (PD) are frequent, but it is unknown whether or not there is progressive loss of physiological sleep architecture or what the causes could be ... [more ▼]

BACKGROUND: Sleep abnormalities in Parkinson's disease (PD) are frequent, but it is unknown whether or not there is progressive loss of physiological sleep architecture or what the causes could be. METHODS: Retrospective review of medical records and polysomnographic data from 46 non-demented PD patients. RESULTS: Sleep latency was correlated with disease duration (F1,44=4.87, P=0.03). Total sleep time (F1,44=8.54, P=0.005), deep sleep time (F1,44=4.06, P=0.05), REM sleep time (F1,44=9.15, P=0.004) and sleep efficiency (SE) (F1,44=10.20, P=0.003) were inversely correlated with disease duration. The same sleep parameters were independent from the degree of motor impairment, dosage of the dopaminergic medications, and age. Subjective sleep complaints could only partially predict abnormalities in polysomnographic (PSG) studies. CONCLUSION: In PD nocturnal sleep 'destructuring' is linked to disease duration and evolves independently from other major disease parameters. [less ▲]

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See detailSleep apnea syndrome in Parkinson's disease. A case-control study in 49 patients.
Diederich, Nico UL; Vaillant, Michel; Leischen, Mike et al

in Movement disorders : official journal of the Movement Disorder Society (2005), 20(11), 1413-8

In PD, the impact of nocturnal respiration on sleep continuity and architecture has not been systematically investigated by polysomnography (PSG). We performed a case-control study with retrospective ... [more ▼]

In PD, the impact of nocturnal respiration on sleep continuity and architecture has not been systematically investigated by polysomnography (PSG). We performed a case-control study with retrospective analysis of PSG data of 49 PD patients. After classifying the PD patients according to their apnea/hypopnea index (AHI), they were matched with 49 controls in terms of age, gender, and AHI. There were 21 PD patients (43%) who had sleep apnea syndrome (SAS), classified as mild (AHI, 5-15) in 10 patients, moderate (AHI, >15-30) in 4 patients, and severe (AHI, > 30) in 7 patients. PD patients had more deep sleep (P = 0.02) and more nocturnal awakenings (P < 0.001) than the controls. Their body mass index (BMI) was lower (P = 0.04), and they maintained a more favorable respiratory profile, with higher mean and minimal oxygen saturation values (P = 0.006 and 0.01, respectively). These differences were preserved when only considering PD patients with AHI > 15. PD patients had less obstructive sleep apneas (P = 0.035), independently from the factor AHI. Only the respiratory changes of 4 PD patients with BMI > 27 and AHI > 15 (8%) approximated those seen in the controls. At an early or middle stage of the disease, non-obese PD patients frequently have AHI values suggesting SAS, however, without the oxygen desaturation profile of SAS. Longitudinal studies of patients with such "abortive" SAS are warranted to establish if this finding reflects benign nocturnal respiratory muscle dyskinesia or constitutes a precursor sign of dysautonomia in PD. [less ▲]

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