Epidemiological time-trend of amyotrophic lateral sclerosis (ALS) over two decades: The French population-based register of ALS in Limousin (FRALim register).

INTRODUCTION: Population-based registers are key to understanding disease patterns. Taking advantage of the long-standing operation of the French register of amyotrophic lateral sclerosis (ALS) in Limousin (FRALim register), we sought to determine the time trends in incidence, clinical features and survival of ALS patients from 2000 to 2020. METHODS: FRALim register included incident cases through multiple sources of ascertainment. A capture-recapture method was used to assess the exhaustiveness of case ascertainment. Crude and standardized incidences were calculated per 100,000 person-years of follow-up (PYFU). Time-period was divided (period 2000 to 2010 and period 2011 to 2020) to compare incidence rates and clinical features. Survival was analyzed using Kaplan-Meier method. Cox proportional hazards model was performed to calculate hazards for the time periods. RESULTS: Overall, 501 incident cases were identified during 21 years. The overall crude incidence was 3.26 (95% CI 2.97 to 3.55) per 100 000 PYFU. The exhaustiveness of the register was estimated at 98.8% (95% CI 97.4-99.6%) by capture-recapture analysis. Several fluctuations were observed without a consistent trend over the last two decades. The crude and standardized incidences were higher in males than females. The peak of incidence was observed in the 75-79 years age band. Almost one-third of the cases exhibited a bulbar onset. There were significant differences in clinical features between time periods. Four hundred and ninety-one cases were included in the survival analysis. The median survival time from diagnosis was 16.0 months (95% CI 14.3 to 17.7 months). Patients in the last decade experienced a lower risk of dying but the difference did not reach statistical significance (adjusted HR: 0.89 (95% CI 0.73 to 1.08, P=0.229). CONCLUSION: We provided reliable epidemiological data over two decades. We showed that incidence has been relatively stable, while clinical variability was observed. A slight improvement in survival time was found in the last decade but it was not statistically significant. Further quality register data are needed to improve our understanding of ALS epidemiological trends.

Population-based epidemiology of amyotrophic lateral sclerosis (ALS) in an ageing Europe--the French register of ALS in Limousin (FRALim register).

BACKGROUND AND PURPOSE: The main objective of establishing the French register of amyotrophic lateral sclerosis (ALS) in the Limousin region (FRALim), was to assess the incidence of ALS, in this ageing region of Europe, over a 12-year period (2000-2011). METHODS: Patients were included if they lived in Limousin at the time of diagnosis of ALS according to El Escorial revised criteria and were identified by at least one of the following sources: (i) the French national body coordinating ALS referral centres; (ii) public and private hospitals in the region; (iii) health insurance data related to long-term diseases. RESULTS: The FRALim register identified 279 incident cases (2000-2011). The crude and European population standardized incidences of ALS were as high as 3.19/100,000 person-years of follow-up (95% CI 2.81-3.56) and 2.58/100,000 person-years of follow-up (95% CI 2.27-2.89) respectively. Median age at onset was 70.8 years (interquartile range 63.1-77.1). The standardized sex incidence ratio (male/female) was 1.3 overall, but 1.1 under the age of 65 years, 1.7 between 65 and 75 years and 1.9 above 75 years. The exhaustiveness of the register has been estimated at 98.4% (95% CI 95.6-99.4) by capture-recapture analysis. CONCLUSION: It was possible for the first time in France to monitor accurately the incidence of ALS over a long time period. It appears to be in the upper range of data reported in western countries. Patterns displayed here might anticipate the epidemiology of ALS in ageing western countries.

Geographical distribution of Toxoplasma gondii genotypes in Asia: A link with neighboring continents.

Defining the pattern of genetic diversity of Toxoplasma gondii is important to understand its worldwide distribution. During the last decades, a large number of studies have been published on Toxoplasma genotypes circulating in Europe, in North and South America. Two continents are still largely unexplored, Africa and, to a less extent, Asia. In this last continent, an increasing number of publications reported genotypes circulating in diverse provinces of China, but very few data are available for other Asian countries. After a systematic database search, 47 papers related to T. gondii genotypes in Asia were analyzed. Genetic characterization of DNA was performed by microsatellite markers, or more usually by a multiplex PCR using 11 PCR-RFLP markers, allowing data comparison to draw a first global picture of the population structure of this parasite throughout Asia. Overall, 390 isolates or DNA extracts were completely typed by PCR-RFLP and/or microsatellite marker methods, revealing 36 different PCR-RFLP or equivalent microsatellite genotypes: 15 genotypes identified by a ToxoDB number and 21 atypical or unique genotypes. The most common genotype found in Asia is the genotype ToxoDB#9 (Chinese 1). The clonal types I, II and II variant, and III were also commonly found in Asia. The geographical distribution of these genotypes across Asia may reflect either a continuum with Europe for the western part of Asia (presence of Type II), or the circulation of strains through animal migration or human activities between Africa and the Southwestern part of Asia (Africa 1 genotype in Turkey or ToxoDB#20 both I Sri-Lanka and in Ethiopia or Egypt). Although there are some indications of a genetic population structure in Southeast Asian countries different from the rest of Asia, more studies in this tropical part of Asia will be necessary for a region which represent as well as Africa one of the missing links of the T. gondii genetic diversity.