A hipofunção vestibular bilateral e a hipostesia vibratória distal dos membros inferiores como preditores do risco de queda no idoso : estudo de coorte transversal ; The bilateral vestibular hypofunction and the distal vibrational hypoesthesia of the lower limbs as predictors of fall risk in elderly population : transversal cohort study

Tese de mestrado, Neurociências, Universidade de Lisboa, Faculdade de Medicina, 2020 ; Introduction: Bilateral vestibular hypofunction (BVH) is a chronic and heterogeneous dysfunction, often idiopathic, but can also occur from physiological aging. It causes a profound impact on the performance of daily life activities and quality of life and confers a 3-fold increase in risk of falling. However, it is often referred as sub or undiagnosed and its handicap is not recognized. Goals: To investigate if the bedside clinical Head Impulse Test (HIT) and the distal vibrational hypoesthesia in the lower limbs test, as well as the physical active lifestyle and age allow to identify the elders with BVH and at risk of falling. Methods: Observational cohort study, with subjects ≥65 years who performed gait, observed in the general ENT outpatient clinic at CHULN between November and December 2017. Movement disorders, paresis or paralysis of one of the lower limbs, any condition that prevented the evaluation and history of ear surgery were excluded. Transversal evaluation was conducted by 5 independent researchers, blinded to the results, after signing the informed consent. Sample characterization was done through a questionnaire, that included, among several aspects, the number of fall events that occurred in the last year (outcome, excluding events not related to the imbalance) and fall risk factors, such as age, gender, vestibular complaints, comorbidities (visual, sensitive, functional, neuropsychological and others), drug therapy, ethanolic and outdoor walking habits (to gauge active physical lifestyle if frequency ³4-6 times/week and duration ³30 minutes/period). The evaluation protocol included vHIT, HIT, and the distal vibratory sensitivity test of the lower limbs. Elderly were divided by outcome criterion in the study group (with) or control (no falls). The vHIT gain cutoff point was calculated from a sample selected from the control group that additionally had no vestibular complaints. BVH was classified as probable ...