Amin Cervantes-Arriaga, Clinical Laboratory of Neurodegenerative Diseases; Movement Disorder Clinic, Mexico City, Mexico
David J. García-Romero, Clinical Laboratory of Neurodegenerative Diseases, Mexico City, Mexico
Marco Muñuzuri-Camacho, Clinical Laboratory of Neurodegenerative Diseases, Mexico City, Mexico
Oscar Esquivel-Zapata, Clinical Laboratory of Neurodegenerative Diseases, Mexico City, Mexico
David Dávila-Ortiz de Montellano, Department of Genetics, National Institute of Neurology and Neurosurgery, Mexico City, Mexico
Leticia Martínez-Ruano, Department of Genetics, National Institute of Neurology and Neurosurgery, Mexico City, Mexico
Ana J. Hernández-Medrano, Clinical Laboratory of Neurodegenerative Diseases, Mexico City, Mexico
María A. Ruiz-Mafud, Clinical Laboratory of Neurodegenerative Diseases, Mexico City, Mexico
Gloria I. Cerda-Hernández, Clinical Laboratory of Neurodegenerative Diseases, Mexico City, Mexico
Arturo Abundes-Corona, Clinical Laboratory of Neurodegenerative Diseases, Mexico City, Mexico
Mayela Rodríguez-Violante, Clinical Laboratory of Neurodegenerative Diseases; Movement Disorder Clinic; Mexico City, Mexico

Objective: This study aims to identify the possible factors that delay the time-to-diagnosis of Huntington’s disease (HD). Methods: A cross-sectional study in HD patients was carried out. Variables registered were CAG repeats, age of onset, primary symptom at onset, age of molecular diagnosis, and time-to-diagnosis, among others. Results: 107 patients (50.5% female) with a mean age of 49 ± 12.8 years (y) were included in the study. Median CAG size was 45 (38-73). Mean age of onset, mean age of molecular diagnosis, and mean time-to-diagnosis were 39 ± 12.9, 45.1 ± 12.1, and 6.4 ± 6.4 years, respectively. In the comparative analysis, the neuropsychiatric- and the young-onset groups had a longer time-to-diagnosis than the motor- and typical-onset groups (p = 0.02 and p < 0.01, respectively). In the linear regression analysis, neuropsychiatric- and young-onset were independent risk factors. Conclusions: Delayed diagnosis showed relation to neuropsychiatric- and early-onset in HD.

Keywords: Huntington’s disease. Molecular pathology. Delayed diagnosis. Age of onset.