Auditory thresholds, otoacoustic emissions and medial olivocochlear system of ex-drug users/Limiares auditivos tonais, emissoes otoacusticas e sistema olivococlear medial de ex-usuarios de drogas

Purpose: to analyze whether the use of illicit drugs may interfere with the peripheral and central auditory system. Methods: 17 subjects were divided according to the kind of consumed drug: 10 individuals in the cannabis group (G1) and seven in the group of crack/cocaine (G2). The groups were subdivided according to the time of drug use: five, six to 10 and more than 15 years. They were evaluated by anamneses, pure tone audiometry, tympanometry, transient evoked otoacoustic emissions (TEOAE) and TEOAE suppression effect. Results: comparing the pure tones of G1 and G2, the worst results were observed in the G2, with a statistically significant difference in the group of one to five years at 250, 500, 6000 and 8000 Hz in the right ear and six to 10 years of about 4000 and 8000 Hz in the left ear. For the users of for more than 15 years, there are pure tones above 25 dBHL from 3000 to 8000 Hz in the right ear. In TEOAE and TEOAE suppression effect, any statistically significant difference was found between G1 and G2 and between the time of drug use. The suppressive effect of TEOAE was present in 79% of the tested ears. Conclusion: the use of crack/cocaine has more deleterious effect in the auditory system if compared to marijuana. The time of use of the drug only influenced the results of the G1. The use of illicit drugs did not cause disorders in the medial olivocochlear system. KEYWORDS: Hearing; Otoacoustic Emissions, Spontaneous; Street Drugs; Cannabis; Cocaine; Crack Cocaine Objetivos: analisar se o uso de drogas ilicitas pode interferir nos sistemas auditivos periferico e central. Metodos: a amostra foi composta por 17 individuos distribuidos conforme o tipo de droga mais consumida: 10 individuos no grupo maconha (G1) e sete no grupo crack/cocaina (G2). Os grupos foram subdivididos segundo o tempo de uso de drogas: um a cinco, seis a 10 e mais que 15 anos. Foram avaliados por meio de anamnese, audiometria tonal liminar, imitanciometria, emissoes otoacusticas transientes (EOAT) e efeito supressor das EOAT. Resultados: comparando os limiares tonais do G1 e G2, observaram-se limiares elevados para o G2, com diferenca estatisticamente significante no grupo de um a cinco anos para 250, 500, 6000 e 8000Hz na orelha direita e de seis a 10 anos para 4000 e 8000Hz na orelha esquerda. Para usuarios por mais que 15 anos, observou-se limiares superiores a 25dBNA de 3000 a 8000Hz na orelha direita. Nas EOAT e efeito supressor das EOAT nao houve diferenca estatistica