Conditional probability analysis between tinnitus and comorbidities in patients attending the National Rehabilitation Institute-LGII in the period 2012–2013

Abstract

Abstract Background Tinnitus is defined as the conscious perception of a sensation of sound that occurs in the absence of an external stimulus. This audiological symptom affects 7–19% of the adult population. The aim of this study is to describe the associated comorbidities present in patients with tinnitus using joint and conditional probability analysis. Patients Patients of both genders, diagnosed with unilateral or bilateral tinnitus, aged between 20 and 45 years, and who had a full computerised medical record, were selected. Methods Study groups were formed on the basis of the following clinical aspects: (1) audiological findings; (2) vestibular findings; (3) comorbidities such as, temporomandibular dysfunction, tubal dysfunction, otosclerosis and, (4) triggering factors of tinnitus noise exposure, respiratory tract infection, use of ototoxic and/or drugs. Results Of the patients with tinnitus, 27 (65%) reported hearing loss, 11 (26.19%) temporomandibular dysfunction, and 11 (26.19%) with vestibular disorders. When performing the joint probability analysis, it was found that the probability that a patient with tinnitus having hearing loss was 27 42 0.65, and 20 42 0.47 for bilateral type. The result for P(A ∩ B)=30%. Bayes’ theorem P( A i B ) = P ( A i ∩ B ) P ( B ) was used, and various probabilities were calculated. Therefore, in patients with temporomandibular dysfunction and vestibular disorders, a posterior probability of P(Aі/B)=31.44% was calculated. Conclusions Consideration should be given to the joint and conditional probability approach as tools for the study of different pathologies.