Avaliação do equilíbrio de indivíduos infectados pelo HTLV-1 por meio da posturografia e do VEMP

Abstract

Introduction: HTLV-1-associated myelopathy (HAM) is a progressive neurological disease that can lead to muscle weakness and changes in gait. Postural instability is one of the first symptoms of the disease and the otoneurological diagnosis is not always changed. Posturography and g-VEMP are instruments that aim to quantitatively assess body balance and the function of the vestibulospinal tract in controlling posture. Objectives: To evaluate the postural balance of individuals infected with HTLV-1 using static posturography and g-VEMP. Materials and Methods: 15 individuals negative for HTLV-1 (G1), 32 individuals asymptomatic for HTLV-1 (G2) and 20 individuals with HAM (G3) completed the balance assessment. Participants underwent static posturography, g-VEMP, Timed Up and Go test, Berg Balance scale and Falls Efficacy Scale – International. Results and Discussion: Participants were comparable in terms of age, body mass index, sex and clinical manifestations such as diabetes and hypertension. The groups HTLV-1 asymptomatic and HAM showed increased g-VEMP latency when compared to the control group (p < 0.001), indicating changes in the transmission of electrical stimuli through the vestibulospinal tract. Regarding posturographic measurements, individuals with HAM showed instability in all test conditions performed. The groups HTLV-1 asymptomatic and negative (control) presented better postural stability compared to HAM group (p<0,001). The results obtained by g-VEMP and posturography suggest that individuals in the HTLV-1 asymptomatic group may be in a transition phase between the control group and HAM. Conclusion: Asymptomatic HTLV-1-infected individuals with impaired balance index and altered VEMP may be more susceptible to the development of HAM. Longitudinal studies are needed to answer this question.