Factors associated to motor development in Down syndrome patients

Alan A. Pérez-Arzola, Servicio de Genética Médica, Hospital General de Zona No. 20, Instituto Mexicano del Seguro Social (IMSS), Puebla, Puebla, México
Israel E. Crisanto-López, Servicio de Genética Médica, Hospital General de Zona No. 20, Instituto Mexicano del Seguro Social (IMSS), Puebla, Puebla, México
Yazmin Hernández-Castañeda, Servicio de Genética Médica, Hospital General de Zona No. 20, Instituto Mexicano del Seguro Social (IMSS), Puebla, Puebla, México
Áurea Vera-Loaiza, Servicio de Genética Médica, Hospital General de Zona No. 20, Instituto Mexicano del Seguro Social (IMSS), Puebla, Puebla, México
Wilbert Salazar-Bonilla, Servicio de Medicina Familiar, Unidad de Medicina Familiar No. 28, IMSS, Tehuacán, Puebla, México
María J. Muñoz-Pérez, Servicio de Genética Médica, Hospital General de Zona No. 20, Instituto Mexicano del Seguro Social (IMSS), Puebla, Puebla, México
Daniela Juárez-Melchor, Servicio de Genética Médica, Hospital General de Zona No. 20, Instituto Mexicano del Seguro Social (IMSS), Puebla, Puebla, México

Background: Down syndrome (DS) is characterized by dysmorphia, psychomotor delay, and systemic conditions, with a prevalence of 1:700 live births. Around 80% of newborns with DS exhibit hypotonia, which is the main cause of gross motor delay. In these children, motor milestones are considered atypical because it is delayed compared to children in the general population. The aim is to describe factors associated to motor development in patients with DS. Methods: An observational, analytical, cross-sectional, and ambispective study was conducted at the Medical Genetics Service of the General Hospital of Zone No. 20, Puebla. Age, sex, cytogenetic mechanism, prematurity, breastfeeding, socioeconomic level, congenital heart disease, thyroid function, and rehabilitation for motor development were analyzed. Descriptive and inferential statistical analysis was performed with the chi square test to identify variables associated with the motor development of patients with DS. Results: Forty patients were analyzed, 22 (55%) male and 18 (45%) female, a median age of 32.5 months; 22 individuals (55%) had regular trisomy 21 and 18 (45%) mosaicism; 37 individuals (92.5%) presented developmental motor delay and 3 (7.5%) reached the milestones. A statistically significant difference was found between having or not having hypothyroidism and milestone achievement (p = 0.046). Conclusions: This study found that patients with DS have delayed motor development and that there is a statistically significant difference between hypothyroidism and motor milestones, highlighting that hypothyroidism did not limit motor development in patients with DS who reached their motor milestones.

Keywords: Down syndrome. Chromosome aberrations. Neurodevelopmental disorders. Developmental disabilities.