To evaluate the association between adolescent and young-adult hearing loss and nonverbal intelligence in rural Nepal.Study design
Cross-sectional assessment of hearing loss among a population cohort of adolescents and young adults.Setting
Sarlahi District, southern Nepal.Patients
Seven hundred sixty-four individuals aged 14 to 23 years.Intervention
Evaluation of hearing loss, defined by World Health Organization criteria of pure-tone average greater than 25 decibels (0.5, 1, 2, 4 kHz), unilaterally and bilaterally.Main outcome measure
Nonverbal intelligence, as measured by the Test of Nonverbal Intelligence, 3rd Edition standardized score (mean, 100; standard deviation, 15).Results
Nonverbal intelligence scores differed between participants with normal hearing and those with bilateral (p = 0.04) but not unilateral (p = 0.74) hearing loss. Demographic and socioeconomic factors including male sex; higher caste; literacy; education level; occupation reported as student; and ownership of a bicycle, watch, and latrine were strongly associated with higher nonverbal intelligence scores (all p < 0.001). Subjects with bilateral hearing loss scored an average of 3.16 points lower (95% confidence interval, −5.56 to −0.75; p = 0.01) than subjects with normal hearing after controlling for socioeconomic factors. There was no difference in nonverbal intelligence score based on unilateral hearing loss (0.97; 95% confidence interval, −1.67 to 3.61; p = 0.47).Conclusion
Nonverbal intelligence is adversely affected by bilateral hearing loss even at mild hearing loss levels. Socio economic well-being appears compromised in individuals with lower nonverbal intelligence test scores.