Differences in the Presentation and Progression of Parkinson's Disease by Sex.

BACKGROUND: Previous studies reported various symptoms of Parkinson's disease (PD) associated with sex. Some were conflicting or confirmed in only one study. OBJECTIVES: We examined sex associations to PD phenotypes cross-sectionally and longitudinally in large-scale data. METHODS: We tested 40 clinical phenotypes, using longitudinal, clinic-based patient cohorts, consisting of 5946 patients, with a median follow-up of 3.1 years. For continuous outcomes, we used linear regressions at baseline to test sex-associated differences in presentation, and linear mixed-effects models to test sex-associated differences in progression. For binomial outcomes, we used logistic regression models at baseline and Cox regression models for survival analyses. We adjusted for age, disease duration, and medication use. In the secondary analyses, data from 17 719 PD patients and 7588 non-PD participants from an online-only, self-assessment PD cohort were cross-sectionally evaluated to determine whether the sex-associated differences identified in the primary analyses were consistent and unique to PD. RESULTS: Female PD patients had a higher risk of developing dyskinesia early during the follow-up period, with a slower progression in activities of daily living difficulties, and a lower risk of developing cognitive impairments compared with male patients. The findings in the longitudinal, clinic-based cohorts were mostly consistent with the results of the online-only cohort. CONCLUSIONS: We observed sex-associated contributions to PD heterogeneity. These results highlight the necessity of future research to determine the underlying mechanisms and importance of personalized clinical management. © 2020 International Parkinson and Movement Disorder Society.

Graft vasculopathy in upper extremity allotransplantation: Results of a retrospective high-resolution ultrasonographic study.

Graft vasculopathy (GV) is the most severe pathologic change of chronic rejection in vascularized composite allotransplantation. Since 2012, the intimal media thickness (IMT) of radial and ulnar arteries was annually monitored by high-resolution ultrasonography in seven bilateral upper extremity transplant (UET) patients. We also investigated the IMT of seven matched healthy subjects (controls). No significant difference between IMT values of controls and UET patients was found. The median IMT values of recipient radial and ulnar arteries were 0.23 mm and 0.25 mm, respectively, while the median IMT values of grafted radial and ulnar arteries were 0.27 mm and 0.30 mm, respectively. There was a statistically significant difference in the IMT values of the grafted and recipient ulnar arteries (p = .043), but this difference was no longer significant when patient #2 was excluded. He showed a significant difference between recipient and grafted arteries and significantly higher IMT values (p = .001) of his grafted arteries compared with those of all transplanted patients. This patient developed GV leading to graft loss 11 years after the transplantation. In conclusion, this study showed a significant IMT increase in an UET recipient who developed GV.

Genomewide association study of Parkinson's disease clinical biomarkers in 12 longitudinal patients' cohorts.

BACKGROUND: Several reports have identified different patterns of Parkinson's disease progression in individuals carrying missense variants in GBA or LRRK2 genes. The overall contribution of genetic factors to the severity and progression of Parkinson's disease, however, has not been well studied. OBJECTIVES: To test the association between genetic variants and the clinical features of Parkinson's disease on a genomewide scale. METHODS: We accumulated individual data from 12 longitudinal cohorts in a total of 4093 patients with 22,307 observations for a median of 3.81 years. Genomewide associations were evaluated for 25 cross-sectional and longitudinal phenotypes. Specific variants of interest, including 90 recently identified disease-risk variants, were also investigated post hoc for candidate associations with these phenotypes. RESULTS: Two variants were genomewide significant. Rs382940(T>A), within the intron of SLC44A1, was associated with reaching Hoehn and Yahr stage 3 or higher faster (hazard ratio 2.04 [1.58-2.62]; P value = 3.46E-8). Rs61863020(G>A), an intergenic variant and expression quantitative trait loci for α-2A adrenergic receptor, was associated with a lower prevalence of insomnia at baseline (odds ratio 0.63 [0.52-0.75]; P value = 4.74E-8). In the targeted analysis, we found 9 associations between known Parkinson's risk variants and more severe motor/cognitive symptoms. Also, we replicated previous reports of GBA coding variants (rs2230288: p.E365K; rs75548401: p.T408M) being associated with greater motor and cognitive decline over time, and an APOE E4 tagging variant (rs429358) being associated with greater cognitive deficits in patients. CONCLUSIONS: We identified novel genetic factors associated with heterogeneity of Parkinson's disease. The results can be used for validation or hypothesis tests regarding Parkinson's disease. © 2019 International Parkinson and Movement Disorder Society.

Hematological phenotypes in children according to the α-globin genotypes.

Limited information is available on the hematological characterization of the α-thalassemia carrier in pediatric age. The objective of this report was to evaluate the red cell indices according to the α-globin genotype in a cohort of children evaluated in Sardinia. Moreover, we verified the frequency of different α-globin genotypes in this cohort. A total of 453 subjects were investigated for hematological indices and for the most common α-globin defects present in Sardinia. Of them, 352 with HbA2≤3.2%, and no iron deficiency anemia were taken into consideration to evaluate the red cell indices according to the α-globin genotype in pediatric age. A total of 11 different α-genotypes were detected, confirming the wide heterogeneity of α-thalassemia in Sardinia. Moreover, our results showed that the hematological parameters in normal children may be conditioned by the clinically occult coinheritance of mild α-thalassemia alleles as already described in the adult population while microcytosis and hypocromia in children without iron deficiency should suggest the coexistence of two α-globin defects. We concluded that recognizing the α-globin gene mutations for a particular population with their particular red cell indices may help pediatricians to perform a correct diagnosis distinguishing among physiological and pathological types of microcytosis and hypocromia.

Seventy-five genetic loci influencing the human red blood cell.

Anaemia is a chief determinant of global ill health, contributing to cognitive impairment, growth retardation and impaired physical capacity. To understand further the genetic factors influencing red blood cells, we carried out a genome-wide association study of haemoglobin concentration and related parameters in up to 135,367 individuals. Here we identify 75 independent genetic loci associated with one or more red blood cell phenotypes at P < 10(-8), which together explain 4-9% of the phenotypic variance per trait. Using expression quantitative trait loci and bioinformatic strategies, we identify 121 candidate genes enriched in functions relevant to red blood cell biology. The candidate genes are expressed preferentially in red blood cell precursors, and 43 have haematopoietic phenotypes in Mus musculus or Drosophila melanogaster. Through open-chromatin and coding-variant analyses we identify potential causal genetic variants at 41 loci. Our findings provide extensive new insights into genetic mechanisms and biological pathways controlling red blood cell formation and function.

Hypothermic pulsatile preservation of kidneys from uncontrolled deceased donors after cardiac arrest - a retrospective study.

Kidneys from uncontrolled donors after cardiac arrest (uDCD) suffer from a period of warm ischemia between cardiac arrest and cold flushing. Aim of the study was to evaluate renal outcomes of uDCD kidneys selected on the basis of renal Resistance Index (RI) and its influence on graft function and survival. The study included 44 kidneys procured from 26 uDCD starting 1.1.2006 until 12.31.2013. The donors (Maastricht category II) underwent cardiopulmonary resuscitation by assisted ventilation and chest compression; the organs were preserved with in situ cold perfusion or a normothermic regional perfusion. All kidneys were perfused on hypothermic (1-4 °C) pulsatile perfusion machine (RM3; Waters Medical System) and discarded when RI ≥0.5 mmHg/ml/min after 6 h of perfusion. There was one (2.2%) primary non function, while 37 recipients (84.1%) experienced delayed graft function. Graft survival was 97.6% at 1 and 3 post-transplantation years. Linear regression models showed that lower values of RI at the end of perfusion were associated with higher values of Modification of Diet in Renal Disease at 3 (P = 0.049) and 6 months after transplantation (P = 0.010) and with higher values of inulin clearance at 1 year (P = 0.030). RI showed to be a useful tool to select uDCD kidneys allowing to achieve good clinical results.

Thalassemia major between liver and heart: Where we are now.

The aim of the study was to assess the current state in terms of liver and heart iron overload as well as of liver and heart related morbidity and mortality in a large cohort of thalassemia patients. Myocardial iron loading was present in 28.9% patients, which was severe in 3.2%. Liver iron was normal in 9.3% and severe in 15%. The rate of cardiac deaths started to decrease between 2000 and 2003 and dropped significantly afterwards. The prescription of combination therapy soon after the hospital admission for decompensated heart failure was associated with a decrease in the short-term mortality. In 111 adult patients who underwent liver elastometry, 14 HCVRNA positive subjects and 2 HCVRNA negative, had stiffness values suggestive of cirrhosis. No cases of hepatocarcinoma were reported. Liver "iron free foci" occurred in a HCV negative patient and the occurrence of a malignant epithelioid hemangioendothelioma led to liver transplantation in another. The study suggests that a subset of patients continues to develop progressive hemosiderosis that may lead to cardiac disease and death. Beyond its key role in preventing myocardial iron overload, liver iron chelation is essential for hampering the onset of hepatic tumors, which may not be limited to hepatocarcinoma.

A genetic score for the prediction of beta-thalassemia severity.

Clinical and hematologic characteristics of beta(ß)-thalassemia are determined by several factors resulting in a wide spectrum of severity. Phenotype modulators are: HBB mutations, HBA defects and fetal hemoglobin production modulators (HBG2:g.-158C>T polymorphism, HBS1L-MYB intergenic region and the BCL11A). We characterized 54 genetic variants at these five loci robustly associated with the amelioration of beta-thalassemia phenotype, to build a predictive score of severity using a representative cohort of 890 ß-thalassemic patients. Using Cox proportional hazard analysis on a training set, we assessed the effect of these loci on the age at which patient started regular transfusions, built a Thalassemia Severity Score, and validated it on a testing set. Discriminatory power of the model was high (C-index=0.705; R(2)=0.343) and the validation conducted on the testing set confirmed its predictive accuracy with transfusion-free survival probability (P<0.001) and with transfusion dependency status (Area Under the Receiver Operating Characteristic Curve=0.774; P<0.001). Finally, an automatized on-line calculation of the score was made available at http://tss.unica.it. Besides the accurate assessment of genetic predictors effect, the present results could be helpful in the management of patients, both as a predictive score for screening and a standardized scale of severity to overcome the major-intermedia dichotomy and support clinical decisions.

IFNL3 polymorphisms and HCV infection in patients with beta thalassemia.

UNLABELLED: BACKGROUND AND RATIONALE FOR THE STUDY: Genome-wide association studies have identified host genetic variation to be critical for spontaneous clearance and treatment response in patients infected with hepatitis C virus. Recently, the role of the IFNL3 polymorphisms in influencing the spontaneous clearance of HCV, the response to interferon and the progression of liver fibrosis, was also demonstrated in patients with thalassemia major infected by genotype 1b. In the present study we retrospectively analyzed 368 anti-HCV positive patients with beta-thalassemia at two Italian major centers in Cagliari and Torino. RESULTS: C/C variant of polymorphism rs12979860 was related to response to interferon treatment and, above all, to spontaneous clearance of the virus. However, the positive predictive power was stronger for viral persistence than spontaneous clearance and in such respect the TT allele was more predictive than CC. The methylation associated polymorphism rs4803221 had independent effects with respect to rs12979860 and the haplotype tagged by SNP rs12979860 and rs4803221 significantly could improve the viral clearance prediction in infected patients. Neither necroinflammation or bilirubin values in the chronic phase of the hepatitis C were related to IFNL3 polymorphisms. No relation among IFNL3 polymorphisms and fibrosis stage directly shown by the liver biopsy was found. CONCLUSIONS: Also in thalassemia the SNPs on chromosome 19q13 closely associates with spontaneous and treatment-induced HCV clearance. The viral clearance prediction is significantly improved by the haplotype tagged by SNP rs12979860 and rs4803221. Neither necroinflammation, bilirubin values or fibrosis stage seem to be related to IFNL3 polymorphisms.

Influence of allograft weight to recipient bodyweight ratio on outcome of cadaveric renal transplantation.

AIM: One of the factors that may affect survival and function of kidney graft is its functional mass. METHODS: In a prospective study, we investigated the impact of the ratio between donor kidney weight in grams and recipient bodyweight in kilograms (DKW/RBW) on creatinine clearance, inulin clearance, and proteinuria: 154 kidneys from deceased donors were weighed and the mean kidney weight was 227 ± 59 g, the bodyweight of the recipients was 64 ± 19 kg. RESULTS: This study showed significant lower values of modification of diet in renal disease (MDRD) in patients with DKW/RBW ratio 2.5 g/kg and between 2.5 and 4.5 g/kg compared with those with DKW/RBW ratio >4.5 g/kg as well as in patients with DKW/RBW ratio <3 g/kg and between 3 and 4 g/kg compared with those with DKW/RBW ratio >4 g/kg; moreover a random coefficient model showed a different time evolution in creatinine clearance values in patients with DKW/RBW ≤ 3 g/kg when compared with patients with DKW/RBW ratio >4 g/kg. There were significant lower values of inulin clearance in patients with DKW/RBW ratio between 2.5 and 4.5 g/kg compared with those with DKW/RBW ratio >4.5 g/kg at 12 post-transplant months and a significantly greater occurrence and earlier appearance of proteinuria in the recipients with DKW/RBW ratio <2.5 g/kg. DKW/RBW ratio did not influence DGF incidence and graft survival. Donor and recipient gender, number of acute rejection episodes and donor age also significantly influenced MDRD values. CONCLUSIONS: Measurements of graft weight as well as donor kidney and recipient body matching should be recommended as influencing renal function.

Impact of heart magnetic resonance imaging on chelation choices, compliance with treatment and risk of heart disease in patients with thalassaemia major.

This study aimed to verify the impact of heart magnetic resonance imaging on chelation choices and patient compliance in a single-institution cohort as well as its predictive value for heart failure and arrhythmias. Abnormal cardiac T2* values determined changes in treatment in most subjects. Heart T2* was confirmed to be highly predictive over 1 year for heart failure and arrhythmias. The choice of chelation regimens known to remove heart iron efficiently was not sufficient by itself to influence the risk. Compliance with treatment had a more remarkable role.

Natural history of hepatitis C in thalassemia major: a long-term prospective study.

BACKGROUND: Transfusion-acquired hepatitis C virus (HCV) remains an important problem among patients with thalassemia. In this study, we evaluated the natural history of post-transfusional hepatitis C in thalassemia major, paying special attention to spontaneous viral clearance, to factors influencing the chronicity rate and fibrosis progression. DESIGN AND METHODS: A prospective study to evaluate the incidence and etiology of transfusion-related hepatitis was started in 1980. In patients who developed hepatitis C, HCV RNA, ALT, and ferritin were measured over time. The correlation between interleukin-28B gene polymorphisms and viral clearance was also analyzed. RESULTS: Seventy-three of 135 patients (62.2%) acquired HCV. An extended follow-up (22 to 30 yr) with HCV RNA assessment was available in 52 patients. Of them, 23 (44.2%) cleared the virus. The proportion of IL-28B genotypes was different between the subjects who cleared the virus and the subjects who did not. Fibrosis progression was similar in HCV RNA-positive and HCV RNA-negative patients. Liver iron was the only factor associated with the fibrosis. CONCLUSIONS: In thalassemia patients with HCV infection, liver iron does not play a major role in influencing the chronicity rate, whereas it is significantly associated with the fibrosis.

Social deprivation and SARS-CoV-2 testing: a population-based analysis in a highly contrasted southern France region.

Background: Testing was the cornerstone of the COVID-19 epidemic response in most countries until vaccination became available for the general population. Social inequalities generally affect access to healthcare and health behaviors, and COVID-19 was rapidly shown to impact deprived population more drastically. In support of the regional health agency in Provence-Alpes-Côte d'Azur (PACA) in South-Eastern France, we analyzed the relationship between testing rate and socio-demographic characteristics of the population, to identify gaps in testing coverage and improve targeting of response strategies. Methods: We conducted an ecological analysis of SARS-CoV-2/COVID-19 testing rate in the PACA region, based on data aggregated at the finest spatial resolution available in France (IRIS) and by periods defined by public health implemented measures and major epidemiological changes. Using general census data, population density, and specific deprivation indices, we used principal component analysis followed by hierarchical clustering to define profiles describing local socio-demographic characteristics. We analyzed the association between these profiles and testing rates in a generalized additive multilevel model, adjusting for access to healthcare, presence of a retirement home, and the age profile of the population. Results: We identified 6 socio-demographic profiles across the 2,306 analyzed IRIS spatial units: privileged, remote, intermediate, downtown, deprived, and very deprived (ordered by increasing social deprivation index). Profiles also ranged from rural (remote) to high density urban areas (downtown, very deprived). From July 2020 to December 2021, we analyzed SARS-CoV-2/COVID-19 testing rate over 10 periods. Testing rates fluctuated strongly but were highest in privileged and downtown areas, and lowest in very deprived ones. The lowest adjusted testing rate ratios (aTRR) between privileged (reference) and other profiles occurred after implementation of a mandatory healthpass for many leisure activities in July 2021. Periods of contextual testing near Christmas displayed the largest aTRR, especially during the last periods of 2021 after the end of free convenience testing for unvaccinated individuals. Conclusion: We characterized in-depth local heterogeneity and temporal trends in testing rates and identified areas and circumstances associated with low testing rates, which the regional health agency targeted specifically for the deployment of health mediation activities.

Genetic modifiers of ß-thalassemia and clinical severity as assessed by age at first transfusion.

BACKGROUND: The clinical and hematologic features of ß-thalassemia are modulated by different factors, resulting in a wide range of clinical severity. The main factors are the type of disease-causing mutation and the ability to produce α-globin and γ-globin chains. In the present study we investigated the respective contributions of known modifiers to the prediction of the clinical severity of ß-thalassemia as assessed by the patients' age at first transfusion. DESIGN AND METHODS: We studied the effect of seven loci in a cohort of 316 Sardinian patients with ß(0)-thalassemia. In addition to characterizing the ß-globin gene mutations, α-globin gene defects and HBG2:g.-158C>T polymorphism, we genotyped two different markers in the BCL11A gene and three in the HBS1L-MYB intergenic region using single nucleotide polymorphism microarrays, imputation and direct genotyping. We performed Cox proportional hazard analysis of the time to first transfusion. RESULTS: According to the resulting model, we were able to explain phenotypic severity to a large extent (Harrell's concordance index=0.72; Cox & Snell R(2)=0.394) and demonstrated that most of the model's discriminatory ability is attributable to the genetic variants affecting fetal hemoglobin production (HBG2:g.-158C>T, BCL11A and HBS1L-MYB loci: C-index=0.68, R(2)=0.272), while the remaining is due to α-globin gene defects and gender. Consequently, significantly distinct survival curves can be described in our population. CONCLUSIONS: This detailed analysis clarifies the impact of genetic modifiers on the clinical severity of the disease, measured by time to first transfusion, by determining their relative contributions in a homogeneous cohort of ß(0)-thalassemia patients. It may also support clinical decisions regarding the beginning of transfusion therapy in patients with ß-thalassemia.

A Sparse Mixture-of-Experts Model With Screening of Genetic Associations to Guide Disease Subtyping.

Motivation: Identifying new genetic associations in non-Mendelian complex diseases is an increasingly difficult challenge. These diseases sometimes appear to have a significant component of heritability requiring explanation, and this missing heritability may be due to the existence of subtypes involving different genetic factors. Taking genetic information into account in clinical trials might potentially have a role in guiding the process of subtyping a complex disease. Most methods dealing with multiple sources of information rely on data transformation, and in disease subtyping, the two main strategies used are 1) the clustering of clinical data followed by posterior genetic analysis and 2) the concomitant clustering of clinical and genetic variables. Both of these strategies have limitations that we propose to address. Contribution: This work proposes an original method for disease subtyping on the basis of both longitudinal clinical variables and high-dimensional genetic markers via a sparse mixture-of-regressions model. The added value of our approach lies in its interpretability in relation to two aspects. First, our model links both clinical and genetic data with regard to their initial nature (i.e., without transformation) and does not require post-processing where the original information is accessed a second time to interpret the subtypes. Second, it can address large-scale problems because of a variable selection step that is used to discard genetic variables that may not be relevant for subtyping. Results: The proposed method was validated on simulations. A dataset from a cohort of Parkinson's disease patients was also analyzed. Several subtypes of the disease and genetic variants that potentially have a role in this typology were identified. Software availability: The R code for the proposed method, named DiSuGen, and a tutorial are available for download (see the references).

Association of APOE-Independent Alzheimer Disease Polygenic Risk Score With Brain Amyloid Deposition in Asymptomatic Older Adults.

BACKGROUND AND OBJECTIVES: Brain amyloid deposition, a major risk factor for Alzheimer's disease (AD), is currently estimated by measuring cerebrospinal fluid or plasma amyloid peptide levels, or by positron-emission tomography imaging. Assessing genetic risks relating to amyloid deposition before any accumulation has occurred would allow for earlier intervention in persons at increased risk for developing AD. Previous work linking amyloid burden and genetic risk relied almost exclusively on APOE, a major AD genetic risk factor. Here, we ask whether a polygenic risk score (PRS) that incorporates an optimized list of common variants linked to AD and excludes APOE is associated with brain amyloid load in cognitively unimpaired elderly adults. METHODS: We included 291 elderly asymptomatic participants from the INveStIGation of AlzHeimer's PredicTors (INSIGHT-preAD) cohort who underwent amyloid imaging, including 83 amyloid-positive (+) participants. We used an Alzheimer's (A) PRS composed of 33 AD risk variants excluding APOE, and selected the 17 variants that showed the strongest association with amyloid positivity to define an optimized (oA) PRS. Participants from the Alzheimer's Disease Neuroimaging Initiative (ADNI) study [228 participants, 90 amyloid (+)] were tested as a validation cohort. Finally, 2,300 AD patients and 6,994 controls from the European Alzheimer's Disease Initiative (EADI) were evaluated. RESULTS: A-PRS was not significantly associated with amyloid burden in the INSIGHT or ADNI cohorts with or without correction for APOE genotype. However, oA-PRS was significantly associated with amyloid status independently of APOE adjustment (INSIGHT OR: 5.26 [1.71-16.88]; ADNI OR: 3.38 [1.02-11.63]). Interestingly, oA-PRS accurately discriminated amyloid (+) and (-) APOE ε4 carriers (INSIGHT OR: 181.6 [7.53-10,674.6]; ADNI OR: 44.94 [3.03-1,277]). A-PRS and oA-PRS showed a significant association with disease status in the EADI cohort (OR: 1.68 [1.53-1.85] and 2.06 [1.73-2.45] respectively). Genes assigned to oA-PRS variants were enriched in ontologies related to Aß metabolism and deposition. DISCUSSION: PRSs relying on AD genetic risk factors excluding APOE may improve risk prediction for brain amyloid, allowing stratification of cognitively unimpaired individuals at risk of AD independent of their APOE status.

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

Introduction: 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. Methods: Thirty-six Parkinsonian patients on DA therapy with (n = 18) and without ICDs (n = 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. Results: 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 (p = 1.6 × 10-3) was replicated in the PPMI cohort and was significantly associated with ICDs in a post hoc pooled analysis (combined p-value 3.3 × 10-5). Two of the 10 most associated variants belonged to genes implicated in cAMP and ERK signaling (rs34193571 in RasGRF2, p = 5 × 10-4; rs1877652 in PDE2A, p = 8 × 10-4) although non-significant after Bonferroni correction. Conclusion: Our results suggest that genes implicated in the signaling pathways linked to G protein-coupled receptors participate to genetic susceptibility to ICDs in PD.