Predictive testing for Huntington disease over 24 years: Evolution of the profile of the participants and analysis of symptoms. Issue 10 (22nd August 2019)

• Record Type: Journal Article
• Authors: Ramond, Francis; Quadrio, Isabelle; Le Vavasseur, Laurence; Chaumet, Hélène; Boyer, Fabrice; Bost, Muriel; Ollagnon‐Roman, Elisabeth
• Is Part Of: Molecular genetics & genomic medicine. Volume 7:Issue 10(2019)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2019-08-22
• Subjects: genetics -- Huntington disease -- neurogenetics -- predictive testing -- presymptomatic testing; Medical genetics -- Periodicals; Genomics -- Periodicals; 616.042
• DOI: 10.1002/mgg3.881
• Languages: English
• ISSNs: 2324-9269

Abstract

Abstract: Background: Huntington disease (HD) is a devastating neurodegenerative autosomal dominant genetic condition. Predictive testing (PT) is available through a defined protocol for at‐risk individuals. We analyzed the over‐24‐years evolution of practices regarding PT for HD in a single center. Methods: We gathered data from the files of all individuals seeking PT for HD in Lyon, France, from 1994 to 2017. Results: 448 out of 567 participants had exploitable data. Age at consultation dichotomized over 24 years toward an eightfold increase in individuals aged >55 (2/94 vs. 30/183; 2% to 16%; p < .0001) and twice as many individuals aged 18–20 (3/94 vs. 12/183; 3%–7%; p < .05). Motives for testing remained stable. The rate of withdrawal doubled over 24 years (9/94 vs. 38/183; 9%–21%; p < .02). Independently of the time period, less withdrawal was observed for married, accompanied, at 50% risk, and symptomatic individuals, and in those able to explicit the motives for testing or taking the test to inform their children. We also assessed the consistency between the presence of subtle symptoms compatible with HD found before the test by the team's neurologist, and the positivity of the molecular test. The concordance was 100% (17/17) for associated motor and cognitive signs, 87% (27/31) for isolated motor signs, and 70% (7/10) for isolated cognitive signs. Furthermore, 91% (20/22) of individuals who requested testing because they thought they had symptoms, were indeed found carriers. Conclusion: This over‐24 years study underlines an increasing withdrawal from protocol and a dichotomization of participants' age. We also show a strong concordance between symptoms perceived by the neurologist or by the patient, and the subsequent positivity of the predictive molecular test. Abstract : The profile of the participants to presymptomatic testing for Huntington Disease has evolved over 24 years, with more older and younger individuals, and more withdrawal from the testing protocol. The presence of symptomatic patients has to be aknowledged among those participants for presymptomatic testing.