Baseline Data
A volunteer sample of 284 individuals were screened, 186 were ineligible, and 36 declined to participate, (Figure 1; eTable 1 in Supplement). The remaining 62 participants were randomized into two groups of 31 participants each, one for betahistine and the other for the placebo. Of those enrolled, five were lost to follow-ups for reasons unrelated to the intervention, missing data at random. 57 participants completed the study, including the intervention and assessments. Out of those, 30 belonged to the placebo group and 27 to the betahistine group (Figure 1).
The median (IQR) age of the study population was 54 (48 to 60) years, with balanced sexes (male = 32; female = 30). The number (percentage) of participants that needed guardian help to fill the THI score was 14 (22.6%), with mild hearing loss was 45 (72.6%), occupation noise exposure was 6 (9.67%), migraine was 10 (16.13%), diabetes mellitus was 6 (9.7%) and with psychiatric illness was 12 (19.4%).
The median (IQR) tinnitus duration was 5 (2 to 10) years. The median (range) THI at baseline was 44 (30 to 60), and the THI subscales, functional, emotional, and catastrophic, were 16 (12 to 26), 16 (12 to 26), and 12 (8 to 14), respectively. Baseline demographic characteristics and THI are listed in Table 1, The location of tinnitus (right, left, or both ears), THI subscales, THI grade and the remaining baseline demographic characteristics are listed in eTable 2 in Supplement. The betahistine group and the placebo group had balanced demographics and THI response (Table 1; eTable 3 in Supplement 1).