Brainstem evoked potential in newly diagnosed patients of subclinical hypothyroidism

Hypothyroidism is known to be associated with impairment of hearing. The hearing impairment may be conductive, sensorineural, or mixed.

The aim is to assess the auditory pathway by brainstem auditory evoked potentials (BAEPs) in newly diagnosed patients of subclinical hypothyroidism and healthy sex- and age-matched controls.

The study included 25 healthy sex- and age-matched controls (Group I) and 25 patients of newly diagnosed subclinical hypothyroidism (Group II). The recording was taken by using RMS EMG EP MK2 equipment. The unpaired Student's t-test was used and a P value <0.05 was considered significant.

Wave V of right ear BAEP in group II was prolonged (6 ± 0.62 ms) compared to group I (5.49 ± 0.26 ms), and wave V of left ear BAEP in group II was prolonged (5.84 ± 0.57 ms) compared to group I (5.47 ± 0.35 ms). There was no significant coefficient of correlation between wave V and inter-peak latency (IPL) I-V compared to thyroid-stimulating hormone (TSH) levels of both the ears.

The prolongation of wave V in BAEPs of both ears suggests that the central auditory pathway is affected significantly in subclinical hypothyroid patients.