Abstract:
Introduction: Hearing loss is one among the major abnormalities present at birth. If undetected will impair speech, language and cognitive development. The critical period for language and speech development is generally regarded as the first three years of life. Children who are identified with hearing at early stage of life and receive early and appropriate interventions have significantly higher developmental functions than those with late identification and intervention.
Objective: The study aimed at determining the prevalence of hearing loss among neonates born in Zanzibar, which is part of United Republic of Tanzania.
Study design
Hospital-based, prospective cross sectional study
Method: This was prospective cross sectional study and conducted in three hospitals and one health Centre where neonatal hearing screening was done in Zanzibar. All babies born from May to October 2016 and whose parents/caretakers consented, enrolled in the study. Data collected using a three staged protocol neonatal hearing screening with OAE and AABR, and other information was collected clinically using specialized forms and check list. A total of 600 neonates were recruited in this study and the data analyzed using the SPSS program.
Results
This study included 600 neonates. Among these, 323 (53.8%) were females and 277 (46.2%) were males. Neonates who underwent 1st OAE, 36.2% failed the test and went for second test. For those who underwent 2nd OAE, 13.8% failed the test and went for AABR. 41.4% of those who went for AABR failed and went for Diagnostic ABR and among these only 3 (25%) failed. Three neonates were diagnosed with hearing loss and they were all males, with bilateral SNHL, making a prevalence of 0.5%. Among those with hearing loss 33.3% had severe SNHL and 66.7% profound SNHL. The most frequent risk factor was ototoxic medication use (11.8%) followed by low apgar score (11%) and family history of childhood hearing loss (7%) and hyperbilirubinemia (2.5%). Hyperbilirubinemia was the only risk factor significantly associated with hearing loss (p=0.001)
Conclusion
The prevalence of hearing loss in neonates was 0.5%, more common in males, bilateral, sensorineural type and associated with risk factors.