Category: Huntington's Disease
Objective: We aim to analyze the main epidemiological characteristics of individuals having a Huntington disease phenotype in Eastern Algeria population.
Background: Huntington’s disease (HD) is the most frequent autosomal dominant chorea in the world, it is caused by an abnormal and unstable repeat expansion of CAG triplets in the HTT gene [1]. HD usually manifests in the adulthood by chorea, cognitive, psychiatric and behavioral impairments chorea [2]–[4]. There is no prior clinical or epidemiological study of HD or of other hereditary chorea in the Algerian population limiting the patients access to care.
Method: We performed a cross-sectional and retrospective analysis of the epidemiological data collected between 2015 and 2022 in Benbadis Constantine University Hospital. We included 45 symptomatic patients from 4 families originating from Eastern Algeria and having a HD phenotype without the presence of signs suggesting other etiologies.
Results: The frequency was 1.25 per 100 000 inhabitants lower than the world average frequency (2.7 per 100,000 inhabitants [5] which can be explained, as in the other African cohorts, by poor access to care [6]. The sex ratio was 2.21, whereas it is 1 in the literature, which may be explained by a fear of social stigmatization of affected women. At the time of inclusion 25 patients are alive with an average age of 49.6 years (23-69 years), the most represented age group is between 40-60 years. The age of motor onset was variable between 21 and 71 years, it is between 40 and 60 years in 62.22% of cases and between 20 and 40 years in a third of cases. This intergenerational variability is related to anticipation phenomena with paternal transmission [7]. The inter-familial variability is probably related to a different number of CAG repeats and/or the effect of different genetic modifiers [8]–[11]. The mean age of death was 56.42 years and is similar to literature data [12]. Genetic testing is needed to confirm the HD diagnosis or of other HD phenocopies (HLD2, C9orf72….).
Conclusion: More efforts need to be made to collect more information, include more families and perform genetic analysis of patients and suspected cases. The goal is to create a national cohort including all the epidemiological, genetic and clinical data of the Algerian population and to establish local management recommendations.
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To cite this abstract in AMA style:
Y. Mecheri, D. Satta, F. Serradj. Epidemiological analysis of autosomal dominant chorea in Eastern Algeria [abstract]. Mov Disord. 2023; 38 (suppl 1). https://www.mdsabstracts.org/abstract/epidemiological-analysis-of-autosomal-dominant-chorea-in-eastern-algeria/. Accessed October 11, 2024.« Back to 2023 International Congress
MDS Abstracts - https://www.mdsabstracts.org/abstract/epidemiological-analysis-of-autosomal-dominant-chorea-in-eastern-algeria/