Role of genetics in amyotrophic lateral sclerosis: a large cohort study in Chinese mainland population.

BACKGROUND: A large number of new causative and risk genes for amyotrophic lateral sclerosis (ALS) have been identified mostly in patients of European ancestry. In contrast, we know relatively little regarding the genetics of ALS in other ethnic populations. This study aims to provide a comprehensive analysis of the genetics of ALS in an unprecedented large cohort of Chinese mainland population and correlate with the clinical features of rare variants carriers. METHODS: A total of 1587 patients, including 64 familial ALS (FALS) and 1523 sporadic ALS (SALS), and 1866 in-house controls were analysed by whole-exome sequencing and/or testing for G4C2 repeats in C9orf72. Forty-one ALS-associated genes were analysed. FINDINGS: 155 patients, including 26 (40.6%) FALS and 129 (8.5%) SALS, carrying rare pathogenic/likely pathogenic (P/LP) variants of ALS causative genes were identified. SOD1 was the most common mutated gene, followed by C9orf72, FUS, NEK1, TARDBP and TBK1. By burden analysis, rare variants in SOD1, FUS and TARDBP contributed to the collective risk for ALS (p<2.5e-6) at the gene level, but at the allelic level TARDBP p.Gly294Val and FUS p.Arg521Cys and p.Arg521His were the most important single variants causing ALS. Clinically, P/LP variants in TARDBP and C9orf72 were associated with poor prognosis, in FUS linked with younger age of onset, and C9orf72 repeats tended to affect cognition. CONCLUSIONS: Our data provide essential information for understanding the genetic and clinical features of ALS in China and for optimal design of genetic testing and evaluation of disease prognosis.

The mutation spectrum of Parkinson-disease-related genes in early-onset Parkinson's disease in ethnic Chinese.

BACKGROUND AND PURPOSE: Recent genetic progress has shown many causative/risk genes linked to Parkinson's disease (PD), mainly in patients of European ancestry. The study aimed to investigate the PD-related genes and determine the mutational spectrum of early-onset PD in ethnic Chinese. METHODS: In this study, whole-exome sequencing and/or gene dosage analysis were performed in 704 early-onset PD (EOPD) patients (onset age ≤45 years) and 1866 controls. Twenty-six PD-related genes and 20 other genes linked to neurodegenerative and lysosome diseases were analysed. RESULTS: Eighty-two (11.6%, 82/704) EOPD patients carrying rare pathogenic/likely pathogenic variants in PD-related genes were identified. The mutation frequency in autosomal recessive inheritance EOPD (42.9%, 27/63) was much higher than that in autosomal dominant inheritance EOPD (0.9%, 12/110) or sporadic EOPD (8.1%, 43/531). Bi-allelic mutations in PRKN were the most frequent, accounting for 5.1% of EOPD cases. Three common pathogenic variants, p.A53V in SNCA, p.G284R in PRKN and p.P53Afs*38 in CHCHD2, occur exclusively in Asians. The putative damaging variants from GBA, PRKN, DJ1, PLA2G6 and GCH1 contributed to the collective risk for EOPD. Notably, the protein-truncating variants in CHCHD2 were enriched in EOPD, especially for p.P53Afs*38, which was also found in three patients from an independent cohort of patients with late-onset PD (n = 1300). Functional experiments confirmed that truncated CHCHD2 variants cause loss of function and are linked to mitochondrial dysfunction. CONCLUSIONS: Our study reveals that the genetic spectrum of EOPD in Chinese, which may help develop genetic scanning strategies, provided more evidence supporting CHCHD2 in PD.

Genome-wide genetic links between amyotrophic lateral sclerosis and autoimmune diseases.

BACKGROUND: Epidemiological and clinical studies have suggested comorbidity between amyotrophic lateral sclerosis (ALS) and autoimmune disorders. However, little is known about their shared genetic architecture. METHODS: To examine the relation between ALS and 10 autoimmune diseases, including asthma, celiac disease (CeD), Crohn's disease (CD), inflammatory bowel disease (IBD), multiple sclerosis (MS), psoriasis, rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), type 1 diabetes (T1D), and ulcerative colitis (UC), and identify shared risk loci, we first estimated the genetic correlation using summary statistics from genome-wide association studies, and then analyzed the genetic enrichment leveraging the conditional false discovery rate statistical method. RESULTS: We identified a significant positive genetic correlation between ALS and CeD, MS, RA, and SLE, as well as a significant negative genetic correlation between ALS and IBD, UC, and CD. Robust genetic enrichment was observed between ALS and CeD and MS, and moderate enrichment was found between ALS and UC and T1D. Thirteen shared genetic loci were identified, among which five were suggestively significant in another ALS GWAS, namely rs3828599 (GPX3), rs3849943 (C9orf72), rs7154847 (G2E3), rs6571361 (SCFD1), and rs9903355 (GGNBP2). By integrating cis-expression quantitative trait loci analyses in Braineac and GTEx, we further identified GGNBP2, ATXN3, and SLC9A8 as novel ALS risk genes. Functional enrichment analysis indicated that the shared risk genes were involved in four pathways including membrane trafficking, vesicle-mediated transport, ER to Golgi anterograde transport, and transport to the Golgi and subsequent modification. CONCLUSIONS: Our findings demonstrate a specific genetic correlation between ALS and autoimmune diseases and identify shared risk loci, including three novel ALS risk genes. These results provide a better understanding for the pleiotropy of ALS and have implications for future therapeutic trials.

Camptocormia in patients with multiple system atrophy at different disease durations: frequency and related factors.

BACKGROUND: Camptocormia is common in patients with multiple system atrophy (MSA). The current study was aimed at assessing the frequency of camptocormia and its related factors in MSA patients with different disease durations. Also, the impact of camptocormia on disability was evaluated. METHODS: A total of 716 patients were enrolled in the study. They were classified into three groups based on disease duration (≤ 3, 3-5, ≥ 5 years). Specific scales were used to evaluate the motor and non-motor symptoms. Disease severity was assessed using the Unified Multiple System Atrophy Rating Scale (UMSARS). The binary logistic regression model was used to explore the factors related to camptocormia. To analyze the impact of camptocormia on disability in patients with disease duration less than 5 years, propensity score matching (PSM) and stratified Cox regression analysis were used. RESULTS: In the current study, we found that the frequency of camptocormia was 8.9, 19.7 and 19.2% when the disease duration was ≤3, 3-5, ≥ 5 years, respectively. In the disease duration ≤3 years group, we found that MSA-parkinsonian subtype (MSA-P) (OR = 2.043, P = 0.043), higher total UMSARS score (OR = 1.063, P < 0.001), older age of onset (OR = 1.047, P = 0.042), and lower score on the frontal assessment battery (FAB) (OR = 0.899, P = 0.046) were associated with camptocormia. Only greater disease severity was associated with camptocormia in the group of patients with disease duration 3-5 years (OR = 1.494, P = 0.025) and in the group of patients with disease duration ≥5 years (OR = 1.076, P = 0.005). There was no significant impact of camptocormia on disability in patients with a disease duration of < 5 years (HR = 0.687, P = 0.463). CONCLUSION: The frequency of camptocormia increased with prolonged disease duration. Disease severity was related to camptocormia at different stages of the disease. The MSA-P subtype, older age of onset, and lower FAB score were associated with camptocormia in the early stage of the disease.

Chinese families with autosomal recessive hereditary spastic paraplegia caused by mutations in SPG11.

BACKGROUND: Spastic paraplegia type 11 (SPG11) mutations are the most frequent cause of autosomal recessive hereditary spastic paraplegia (ARHSP). We are aiming to identify the causative mutations in SPG11 among families referred to our center with ARHSP in a Chinese population. METHODS: Targeted next-generation sequencing was performed on the patients to identify disease-causing mutations. Variants were analyzed according to their predicted pathogenicity and their relevance to the clinical phenotypes. The segregation in the family members was validated by Sanger sequencing. RESULTS: A total of 12 mutations in SPG11 gene from 9 index cases were identified, including 6 frameshift mutations, 3 missense mutations, 1 nonsense mutation, 1 splicing mutation, and 1 intron deletion mutation. In 6 of these patients, the mutations were homozygous, and the other 3 patients carried two compound heterozygous mutations. Six mutations were novel; 2 were classified as pathogenic, 1 were considered as likely pathogenic, and the other 3 were variants of unknown significance. Additionally, 1 missense heterozygous variant we found was also carried by amyotrophic lateral sclerosis (ALS) patient. Clinically and electrophysiologically, some of our ARHSP patients partially shared various features of autosomal-recessive juvenile amyotrophic lateral sclerosis (ARJALS), including combination of both UMN and LMN degeneration. CONCLUSIONS: The results contribute to extending of the SPG11 gene mutation spectrum and emphasizing a putative link between ARHSP and ARJALS.

Factors influencing cognitive function in patients with Huntington's disease from China: A cross-sectional clinical study.

BACKGROUND AND AIM: Huntington's disease (HD) is an autosomal dominant inherited neurodegenerative disorder caused by CAG repeats expansion. Cognitive decline contributes to the loss of daily activity in manifest HD. We aimed to examine the cognition status in a Chinese HD cohort and explore factors influencing the diverse cognitive domains. METHODS: A total of 205 participants were recruited in the study with the assessment by neuropsychological batteries, including the mini-mental state examination (MMSE), Stroop test, symbol digit modalities test (SDMT), trail making test (TMT), verbal fluency test (VFT), and Hopkins verbal learning test-revised, as well as motor and psychiatric assessment. Pearson correlation and multiple linear regression models were applied to investigate the correlation. RESULTS: Only 41.46% of patients had normal global function first come to our center. There was a significantly difference in MMSE, Stroop test, SDMT, TMT, and VFT across each stage of HD patients (p < .05). Apathy of PBA-s was correlated to MMSE, animal VFT and Stroop-interference tests performance. Severity of motor symptoms, functional capacity, age, and age of motor symptom onset were correlated to all neuropsychological scores, whereas education attainment and diagnostic delay were correlated to most neuropsychological scores except TMT. Severity of motor symptoms, functional capacity, and education attainment showed independent predicting effect (p < .05) in diverse cognitive domains. CONCLUSION: Cognitive impairment was very common in Chinese HD patients at the first visit and worse in the patients in advanced phase. The severity of motor symptoms and functional capacity were correlated to the diverse cognitive domains.

Neutrophil-to-lymphocyte ratio in sporadic amyotrophic lateral sclerosis.

The neutrophil-to-lymphocyte ratio (NLR) is considered a robust prognostic biomarker for predicting patient survival outcomes in many diseases. However, it remains unclear whether it can be used as a biomarker for amyotrophic lateral sclerosis (ALS). To correlate NLR with disease progression and survival in sporadic ALS, 1030 patients with ALS between January 2012 and December 2018 were included in this study. These patients were assigned into three groups according to their NLR values: Group 1 (NLR < 2, n = 544 [52.8%]), Group 2 (NLR = 2-3, n = 314 [30.5%]), and Group 3 (NLR > 3, n = 172 [16.7%]). All patients were followed up until April 2020. Patients in Group 3 had a significantly older onset age, a lower score on the Revised ALS Functional Rating Scale, and rapidly progressing disease conditions. Furthermore, faster disease progression rates were associated with higher NLR values (odds ratio = 1.211, 95% confidence interval [CI]: 1.090-1.346, P < 0.001) after adjusting for other risk factors. Compared with Groups 1 and 2, the survival time in Group 3 was significantly shorter (log-rank P = 0.002). The NLR value was considered an independent parameter for the prediction of survival in ALS patients after normalizing for all other potential parameters (hazard ratio [HR] = 1.079, 95% CI: 1.016-1.146, P = 0.014). The effects on ALS survival remained significant when adjusted for treatment (HR = 1.074, 95% CI: 1.012-1.141, Ptrend = 0.019) or when considering the stratified NLR value (HR = 1.115, 95% CI: 1.009-1.232, Ptrend = 0.033). Thus, the NLR may help to predict the rate of disease progression and survival in patients with sporadic ALS. The study was approved by the Institutional Ethics Committee of West China Hospital of Sichuan University, China (approval No. 2015 (236)) on December 23, 2015.

The Cold Hand Sign in Multiple System Atrophy: Frequency-Associated Factors and Its Impact on Survival.

Background: Few studies have focused on the cold hand sign (CHS), a red flag symptom, in multiple system atrophy (MSA). Objective: This study aimed to investigate the frequency and correlative factors of CHS in patients with MSA and the impact of its early occurrence on the survival of these patients. Methods: A total of 483 patients with MSA were enrolled in this study, and the motor and non-motor symptoms between patients with MSA with and without CHS were compared. Moreover, patients with disease duration ≤ 3 years at baseline were followed, and the association between CHS and survival of patients with MSA was examined. Results: The frequencies of CHS in patients with MSA were 20, 15.4, and 25.3% in MSA, MSA-parkinsonian subtype (MSA-P), and MSA-cerebellar subtype (MSA-C), respectively. Higher Unified Multiple System Atrophy Rating Scale (UMSARS) scores and higher Non-Motor Symptom Scale (NMSS) scores at baseline were associated with CHS in MSA. CHS was associated with shorter survival after adjusting for baseline diagnosis subtype, age at onset, sex, orthostatic hypotension, disease duration, autonomic onset, UMSARS total score, and NMSS score (p = 0.001; HR = 3.701; 95% CI = 1.765-7.760). Conclusion: CHS is not rare in patients with MSA. Greater disease severity and more severe non-motor symptoms were associated with CHS in patients with MSA. Patients with early occurrence of CHS had a poor prognosis.

Association Analysis of WNT3, HLA-DRB5 and IL1R2 Polymorphisms in Chinese Patients With Parkinson's Disease and Multiple System Atrophy.

Background: The association between inflammation and neurodegeneration has long been observed in parkinson's disease (PD) and multiple system atrophy (MSA). Previous genome-wide association studies (GWAS) and meta-analyses have identified several risk loci in inflammation-associated genes associated with PD. Objective: To investigate whether polymorphisms in some inflammation-associated genes could modulate the risk of developing PD and MSA in a Southwest Chinese population. Methods: A total of 2,706 Chinese subjects comprising 1340 PD, 483 MSA and 883 healthy controls were recruited in the study. Three polymorphisms (rs2074404 GG/GT/TT, rs17425622 CC/CT/TT, rs34043159 CC/CT/TT) in genes linked to inflammation in all the subjects were genotyped by using the Sequenom iPLEX Assay. Results: The allele G of WNT3 rs2074404 can increase risk on PD (OR: 1.048, 95% CI: 1.182-1.333, p = 0.006), exclusively in the LOPD subgroup (OR: 1.166, 95% CI:1.025-1.327, p = 0.019), but not in EOPD or MSA. And the recessive model analysis also demonstrated an increased PD risk in GG genotype of this locus (OR = 1.331, p = 0.007). However, no significant differences were observed in the genotype distributions and alleles of HLA-DRB5 rs17425622 and IL1R2 rs34043159 between the PD patients and controls, between the MSA patients and controls, or between subgroups of PD or MSA and controls. Conclusion: Our results suggested the allele G of WNT3 rs2074404 have an adverse effect on PD and particularly, on the LOPD subgroup among a Chinese population.

Creatine kinase in the diagnosis and prognostic prediction of amyotrophic lateral sclerosis: a retrospective case-control study.

Creatine kinase is a muscle enzyme that has been reported at various levels in different studies involving patients with amyotrophic lateral sclerosis. In the present retrospective case-control study, we included 582 patients with amyotrophic lateral sclerosis and 582 age- and sex-matched healthy controls. All amyotrophic lateral sclerosis participants received treatment in the Department of Neurology, West China Hospital, China, between May 2008 and December 2018. Serum creatine kinase levels in patients with amyotrophic lateral sclerosis were significantly higher than those in healthy controls. Subgroup analysis revealed that serum creatine kinase levels in men were higher than those in women in both amyotrophic lateral sclerosis patients and healthy controls. Compared with patients with bulbar-onset amyotrophic lateral sclerosis, patients with limb-onset amyotrophic lateral sclerosis had higher creatine kinase levels. Spearman's correlation analysis revealed that serum creatine kinase levels were not correlated with body mass index, Amyotrophic Lateral Sclerosis Functional Rating Scale-Revised score, or progression rate. After adjusting for prognostic covariates, higher log creatine kinase values were correlated with higher overall survival in the amyotrophic lateral sclerosis patients. We also investigated the longitudinal changes in serum creatine kinase levels in 81 amyotrophic lateral sclerosis patients; serum creatine kinase levels were decreased at the second blood test, which was sampled at least 6 months after the first blood test. Together, our results suggest that serum creatine kinase levels can be used as an independent factor for predicting the prognosis of amyotrophic lateral sclerosis patients. This study received ethical approval from the Ethics Committee of West China Hospital, China (approval No. 2015(236)) on December 23, 2015.

Genetic Analysis of Prosaposin, the Lysosomal Storage Disorder Gene in Parkinson's Disease.

Recent genetic studies clearly indicate that variants in several lysosomal genes act as risk factors for idiopathic Parkinson's disease (PD). Variants in the co-activator of glucocerebrosidase gene (GBA) and the four active saposins (Sap A-D) which are encoded by the prosaposin gene (PSAP) are of particular interest; however, their genetic roles in PD are unknown. Whole-exome sequencing and Sanger sequencing were used to assess the genetic etiology of 400 autosomal dominant inherited PD (ADPD) and 300 sporadic PD (SPD) patients. Variants from public databases, including Genome Aggregation Database-East Asian (GnomAD_EAS) and Chinese Millionome Database (CMDB), were used as control groups. Burden analysis based on gene and domains level were performed to investigate the role of rare PSAP variants in PD. Six rare and likely pathogenic variants, located in the Sap A-D domains, were identified and accounted for 0.75% (3/400) of ADPD and 1.33% (4/300) of SPD in the Chinese population. Based on the gene or domain, burden analysis showed that damaging missense variants in SapC had statistical significance on the risk of developing PD. Interestingly, rs4747203, an intronic variant potentially linked to PSAP expression, was associated with reduced risk for PD (p = 8.6e-7 in GnomAD EAS and p = 0.002 in Chinese). Clinically, patients carrying the likely pathogenic variants presented typical PD motor symptoms and responded well to levodopa treatment. Six out of seven patients carrying the likely pathogenic variants of PSAP presented slow disease progression, and none of the patients developed cognitive impairment. Our study expands the spectrum of mutations associated with the risk of developing PD and enhances the understanding of the relationship of the clinical phenotype of PD with PSAP variants.

Rare Variants Analysis of Lysosomal Related Genes in Early-Onset and Familial Parkinson's Disease in a Chinese Cohort.

BACKGROUND: Genetic studies have indicated that variants in several lysosomal genes are risk factors for idiopathic Parkinson's disease (PD). However, the role of lysosomal genes in PD in Asian populations is largely unknown. OBJECTIVE: This study aimed to analyze rare variants in lysosomal related genes in Chinese population with early-onset and familial PD. METHODS: In total, 1,136 participants, including 536 and 600 patients with sporadic early-onset PD (SEOPD) and familial PD, respectively, underwent whole-exome sequencing to assess the genetic etiology. Rare variants in PD were investigated in 67 candidate lysosomal related genes (LRGs), including 15 lysosomal function-related genes and 52 lysosomal storage disorder genes. RESULTS: Compared with the autosomal dominant PD (ADPD) or SEOPD cohorts, a much higher proportion of patients with multiple rare damaging variants of LRGs were found in the autosomal recessive PD (ARPD) cohort. At a gene level, rare damaging variants in GBA and MAN2B1 were enriched in PD, but in SCARB2, MCOLN1, LYST, VPS16, and VPS13C were much less in patients. At an allele level, GBA p. Leu483Pro was found to increase the risk of PD. Genotype-phenotype correlation showed no significance in the clinical features among patients carrying a discrepant number of rare variants in LRGs. CONCLUSION: Our study suggests rare variants in LRGs might be more important in the pathogenicity of ARPD cases compared with ADPD or SEOPD. We further confirm rare variants in GBA are involve in PD pathogenecity and other genes associated with PD identified in this study should be supported with more evidence.

Genetic Analysis of ZNF Protein Family Members for Early-Onset Parkinson's Disease in Chinese Population.

Functional and genetic studies have identified association between several Zinc finger (ZNF) proteins and Parkinson's disease (PD). However, most of them were still awaiting further replications, especially in the Asian population. Here, we systematically selected PD-relevant ZNF genes and analyzed the genetic associations between these ZNFs and PD in a large Chinese PD cohort. We identified rare variants (minor allele frequency < 0.01) in 743 unrelated patients with early-onset PD (EOPD, age at onset < 50 years) using whole exome sequencing and evaluated the association between rare variants and EOPD at both allele and gene levels. Totally 91 rare variants were identified in ZNF746, ZNF646, ZNF184, ZNF165, ZND219, and GLIS1. One variant p.R373H in ZNF219 and two variants p.G161D and p.R158H in ZNF746 were significantly associated with EOPD, and gene-based burden analysis showed enrichment of rare variants of ZNF746 in EOPD. Our findings build up the connection between ZNF746 and PD from a genetic perspective for the first time, supplement current understanding for the genetic role of ZNFs in EOPD, and broaden the mutation spectrum in PD.

Sleep-related symptoms in multiple system atrophy: determinants and impact on disease severity.

BACKGROUND: Sleep disorders are common but under-researched symptoms in patients with multiple system atrophy (MSA). We investigated the frequency and factors associated with sleep-related symptoms in patients with MSA and the impact of sleep disturbances on disease severity. METHODS: This cross-sectional study involved 165 patients with MSA. Three sleep-related symptoms, namely Parkinson's disease (PD)-related sleep problems (PD-SP), excessive daytime sleepiness (EDS), and rapid eye movement sleep behavior disorder (RBD), were evaluated using the PD Sleep Scale-2 (PDSS-2), Epworth Sleepiness Scale (ESS), and RBD Screening Questionnaire (RBDSQ), respectively. Disease severity was evaluated using the Unified MSA Rating Scale (UMSARS). RESULTS: The frequency of PD-SP (PDSS-2 score of ≥18), EDS (ESS score of ≥10), and RBD (RBDSQ score of ≥5) in patients with MSA was 18.8%, 27.3%, and 49.7%, respectively. The frequency of coexistence of all three sleep-related symptoms was 7.3%. Compared with the cerebellar subtype of MSA (MSA-C), the parkinsonism subtype of MSA (MSA-P) was associated with a higher frequency of PD-SP and EDS, but not of RBD. Binary logistic regression revealed that the MSA-P subtype, a higher total UMSARS score, and anxiety were associated with PD-SP; that male sex, a higher total UMSARS score, the MSA-P subtype, and fatigue were associated with EDS; and that male sex, a higher total UMSARS score, and autonomic onset were associated with RBD in patients with MSA. Stepwise linear regression showed that the number of sleep-related symptoms (PD-SP, EDS, and RBD), disease duration, depression, fatigue, and total Montreal Cognitive Assessment score were predictors of disease severity in patients with MSA. CONCLUSIONS: Sleep-related disorders were associated with both MSA subtypes and the severity of disease in patients with MSA, indicating that sleep disorders may reflect the distribution and degree of dopaminergic/non-dopaminergic neuron degeneration in MSA.

Blood hemoglobin A1c levels and amyotrophic lateral sclerosis survival.

BACKGROUND: There are inconsistences regarding the correlation between diabetes or fasting blood glucose concentrations and the risk and survival of amyotrophic lateral sclerosis (ALS) in the previous studies. Moreover, the association between hemoglobin A1c (HbA1c) levels, which reflect long-term glycemic status, and ALS survival was not examined. METHODS: A prospective cohort study including 450 Chinese sporadic ALS patients (254 men and 196 women; mean age: 55.4 y). We identified 223 deaths during average 1.6 years of follow-up. We assessed levels of fasting HbA1c (primary exposure) and glucose (secondary exposure) via ion exchange high-performance liquid chromatography and hexokinase/glucose-6-pgosphate dehydrogenase methods, respectively. Multivariate Cox proportional hazards regression model was used to calculate hazard ratios (HRs) and 95% confidence intervals (CIs) of ALS mortality across the exposures. RESULTS: Our results indicated that, higher levels of HbA1c, but not fasting blood glucose concentrations, were significantly associated with higher risks of mortality. The adjusted HR was 1.40 (95% confidence interval (95% CI): 1.02-1.99) for HbA1c of 5.7-6.4%, and 2.06 (95% CI: 1.07-3.96) for HbA1c ≥6.5%, relative to HbA1c <5.7% (P trend =0.01), after adjustment for age, smoking, obesity, disease severity, site of onset, lifestyle, and other potential confounders. The adjusted HR was 1.38 (95% CI: 0.81-2.35, P trend =0.13) for fasting glucose concentrations ≥7.0 mmol/L vs <5.6 mmol/L. We did not observe any significant interactions between HbA1c levels and age, sex, smoking, body mass index, rate of disease progression of ALS, and site of onset (P-interactions >0.05 for all). CONCLUSION: In this prospective study, we observed that individuals with higher HbA1c levels at the baseline had higher risk of mortality, which is independent of other known risk factors.

Analysis and meta-analysis of five polymorphisms of the LINGO1 and LINGO2 genes in Parkinson's disease and multiple system atrophy in a Chinese population.

Whether polymorphisms rs11856808 and rs9652490 of the Leucine-rich repeat and Ig domain containing, Nogo receptor-interacting protein-1 (LINGO1) gene, as well as rs10968280, rs13362909 and rs7033345 of the LINGO2 gene, increase the risk for Parkinson's disease (PD) is controversial. Considering the overlap of the clinical and pathological characteristics among PD and multiple system atrophy (MSA), we explored the associations between these five polymorphisms and PD and MSA in a Chinese population. A total of 1055 PD patients, 320 MSA patients, and 810 healthy controls (HCs) were genotyped for these five polymorphisms in LINGO1 and LINGO 2 using Sequenom iPLEX Assay technology. Moreover, after combining our results with available published data, a meta-analysis was conducted to investigate the associations between LINGO 1 rs11856808 and rs9652490 and the risk of PD. The frequency of the minor alleles "T" of LINGO1 rs11856808 was significantly lower in PD than that in HCs (p = 0.011, OR 0.89, 95 % CI 0.81-0.97), but not in MSA. Moreover, there were no significant differences in the minor allele frequency distributions of the other four polymorphisms between PD and HCs, and between MSA and HCs. The meta-analysis showed a lack of association of rs9652490 and PD, regardless of the genetic model or ethnic origin. However, the rs11856808 allele decreased the risk of PD in patients of Asian origin in a dominant genetic model. Our findings suggest that rs11856808 plays a protective role by decreasing the risk for PD, but not for MSA, in Asian population, the other four polymorphisms do not contribute to the risk for PD and MSA.

Determinants of the quality of life in Parkinson's disease: results of a cohort study from Southwest China.

BACKGROUND: The determinants of the quality of life (QoL) of patients with Parkinson's disease (PD) in Chinese population remain largely unknown. METHODS: A total of 649 PD patients from Southwest China participated in this cross-sectional study. Non-motor Symptoms Scale (NMSS) was used to evaluate the non-motor symptoms (NMS), whereas PD Quality of Life Questionnaire (PDQ-39) was used to assess the QoL of the PD patients. Multiple stepwise regression analysis was conducted to identify the determinants of the QoL. RESULTS: NMS, H-Y stage, female, disease duration, UPDRS III score, single/divorced/widowed, and motor complications accounted for 66.3% of the variables in the multiple regression analysis and were the negative determinants of the QoL. Among these variables, NMS and H-Y stage accounted for 46.7% and 14.5%, respectively. NMS were closely associated with each domain of PDQ-39. Female sex especially predicted poor emotional well-being and bodily discomfort, whereas single/divorced/widowed especially predicted poor stigma and social support of PD patients. Comorbidity, motor complications and rural living predicted poor mobility, activities of daily living and emotional well-being, respectively. CONCLUSION: Both demographic and disease-specific factors influence the QoL in PD patients. NMS are the strongest independent negative determinant of the overall QoL and closely associated with each domain of PDQ-39. The treatment of NMS may help to improve the QoL of PD patients.

SNCA variants rs2736990 and rs356220 as risk factors for Parkinson's disease but not for amyotrophic lateral sclerosis and multiple system atrophy in a Chinese population.

Previous studies found that polymorphisms rs2736990 and rs356220 in the alpha-synuclein (SNCA) gene increase the risk for Parkinson's disease (PD) in a Caucasian population. In consideration of the overlapping of clinical manifestations and pathologic characteristics among PD, amyotrophic lateral sclerosis (ALS), and multiple system atrophy (MSA), the possible associations of these 2 polymorphisms and 3 neurodegenerative diseases were studied in the Chinese population. A total of 1011 PD, 778 sporadic ALS (SALS), 264 MSA patients, and 721 healthy controls (HCs) were studied. All subjects were genotyped for the 2 polymorphisms using polymerase chain reaction and direct sequencing. Significant differences in the genotype frequencies (p = 0.0188 and 0.0064, respectively) and minor allele frequencies (MAFs) (p = 0.0065 and 0.0095, respectively) of rs2736990 and rs356220 were observed between the PD patients and HCs. Moreover, significant differences were found between the early-onset PD patients (<50 years) and matched controls but not in the late-onset PD patients (≥50 years). However, no differences were observed between subgroups with regard to clinical features, such as sex, onset symptoms (tremor or rigidity), cognition (normal or abnormal), and anxiety and depression (presence or absence). No significant differences were found in the genotype frequencies and MAFs of these 2 single-nucleotide polymorphisms between SALS patients and HCs and between MSA patients and HCs. No significant differences were found between subgroups with regard to the clinical presentation of SALS and MSA. Our results show that rs2736990 and rs356220 in SNCA decreased the risk for PD in a Chinese population. These candidate polymorphisms were unlikely to be the causes of SALS and MSA in this population.