ABSTRACT
Hypothyroidism is a common disease in Iran. It can interfere with the normal function of some of the systems in the human body; one of the symptoms it is associated with is hoarseness, a of dysfunction that may occur in such patients. This study has been performed to determine the details of voice disorders in hypothyroidism. Hypothyroidism was confirmed in fifteen patients examined by an endocrinologist, using hormone laboratory tests. In all patients T4 level was less than 5 mg[d] and TSH level was over 10 mu/L. the vocalization and speech quality of all the cases were recorded and analyzed using the MDVP program by Visipitch system. The result of this study indicates that the majority of cases suffer from some degrees of dysphonia; dryness of pharynx and larynx, hoarseness and the feeling of having a lump in their larynx are among the common complaints of these patients. Fundamental frequency [FO] in their voices with mean and SD [200 +/- 47 Hz] indicates a meaningful difference with normal values [P<0/01]. Jitter parameter in studied patients with mean and SD [1/79 +/- 1/31] also indicates a meaningful difference with normal values [p<0/01]. This is also the case with the Shimmer parameter in the studied patients with mean and SD [6/15 +/- 4.66] implying a meaningful difference with normal values [p<0/01]. This study indicates that voice problems are very common in hypothyroidism