Age at onset of amyotrophic lateral sclerosis in China

Zhang

J Neurol Neurosurg Psychiatry

et al. 2015

116

114

The clinical characteristics and outcomes of Chinese patients with sporadic ALS were different compared with patients from other countries. Compared with other studies, the age at onset of Chinese patients was earlier, the percentage of bulbar-onset ALS was lower and the prognosis was better. This study substantially advances the understanding of the clinical features and epidemiology of this rare disease.

Section: Discussionsupporting

confidence: 90%

Natural history and clinical features of sporadic amyotrophic lateral sclerosis in China

Zhang

J Neurol Neurosurg Psychiatry

et al. 2015

116

114

“…It is argued that possible protective hormonal factors in women may be related to this observed rate [18]. In this study, there is no evidence of a significant decline in the male:female ratio among postmenopausal age groups.…”

Section: Discussioncontrasting

confidence: 49%

“…Reports from China have suggested that C9orf72 mutations are not a common cause of familial or sporadic ALS in Chinese mainland [17]. In addition, the life expectancy of the defined population may also affect the incidence of ALS; the average life expectancy in China is approximately 5 years shorter than that in developed countries [18]. Chinese population with fewer number of old people will partly lead to lower rates.…”

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Using the Capture-Recapture Method to Estimate the Incidence of Amyotrophic Lateral Sclerosis in Beijing, China

Zhou

Qian

et al. 2018

Neuroepidemiology

Background: To assess the total, gender-related and ageing process-related incidence rates of amyotrophic lateral sclerosis (ALS) in Beijing, China. Determine whether the decreased male to female ratio among postmenopausal age groups. Methods: We used the 2-source capture-recapture method to estimate the incidence of ALS in Beijing. The primary and secondary data sources were from diagnostic hospitals and assisted care institutions in the same area from 2010 to 2015. Results: A total of 562 cases and 283 cases were extracted from 2 data sources, and a total of 962 patients diagnosed with ALS within the 6-year period were estimated (95% CI 883–1041). The average yearly incidence was 0.77/100,000 persons (95% CI 0.71–0.83). The female to male ratio was 1.63. The incidence was associated with age and peaked in the 55–64 year age group. There was no obvious decline in the male:female ratio among postmenopausal age groups. Conclusions: The total incidence of ALS in Beijing is similar to international reports. The onset of ALS is not merely the result of ageing.

“…A recent report [120] describing a Chinese ALS cohort suggested that epidemiological characteristics of Chinese MND patients were similar to those observed in international populations. However a separate investigation [111] confirmed the earlier age at onset of ALS in China as compared to Caucasian populations. In addition, the significantly low frequency of known ALS causing genes has been reported in Asian populations, including the rare mutations in C9orf72 and VCP.…”

Section: Discussionmentioning

confidence: 71%

Genetics of amyotrophic lateral sclerosis in the Han Chinese

He¹

Amyotrophic lateral sclerosis is the most frequently occurring neuromuscular degenerative disorders, and has an obscure aetiology. Whilst major progress has been made, the majority of the genetic variation involved in ALS is, as yet, undefined. In this thesis, multiple genetic studies have been conducted to advance our understanding of the genetic architecture of the disease. In the light of the paucity of comprehensive genetic studies performed in Chinese, the presented study focused on advancing our current understanding in genetics of ALS in the Han Chinese population. To identify genetic variants altering risk of ALS, a genome-wide association study (GWAS) was performed.The study included 1,324 Chinese ALS cases and 3,115 controls. After quality control, a number of analyses were performed in a cleaned dataset of 1,243 cases and 2,854 controls that included: a genome-wide association analysis to identify SNPs associated with ALS; a genomic restricted maximum likelihood (GREML) analysis to estimate the proportion of the phenotypic variance in ALS liability due to common SNPs; and a genebased analysis to identify genes associated with ALS. There were no genome-wide significant SNPs or genes associated with ALS. However, it was estimated that 17% (SE: 0.05; P=6×10 -5 ) of the phenotypic variance in ALS liability was due to common SNPs. The top associated SNP was within GNAS (rs4812037; p =7×10 -7 ). GNAS was also the most associated gene from the gene-based study (p =2×10 -5 ). Based on GWAS data, a fragment-length and repeat-primed PCR was performed to determine GGGGCC copy number and expansion within the C9orf72 gene in the cohorts (1,092 sporadic ALS and 1,062 controls) from China.A haplotype analysis of 23 SNPs within and surrounding the C9orf72 gene was performed.The C9orf72 hexanucleotide (GGGGCC)n repeat expansion (HRE) was found in three sALS patients (0.3%) but not in control subjects (p = 0.25, Fisher's exact test). Two cases 2 with HRE did not harbor four risk alleles that have previously been determined to be Contributions by others to the thesis