Risk factors are the characteristics or habits that increase the chances of developing a disease. As with any other condition, APD has its own risk factors, and one of them is a history of persistent or recurrent otitis media with effusion (OME) during childhood and its consequent hearing loss (Hall & Derlacki, 1986; Tomlin & Rance, 2014; Graydon et al., 2017; Nittrouer & Lowenstein, 2024). OME is popularly called “Glue ear”.
Let’s first understand what Glue ear is …
Otitis media with effusion (“Glue ear”) is a build-up of fluid within the middle ear without signs of inflammation (such as pain, for instance). This condition is very common in children under 3 years old, and it usually causes hearing loss as the fluid interferes with the passage of sounds into the inner ear, where sounds are processed by the cochlea. The hearing loss caused by glue ear is conductive (temporary), it fluctuates significantly from a mild to moderate level in both ears asymmetrically and can persist for weeks or months. While OME is very common, and it usually resolves spontaneously, recurrent (3 or more episodes) or persistent (when it persists for three or more months) OMEs are more complicated as they might cause further complications, usually due to the impact of the hearing loss. For example, speech development might be affected as the child might struggle to perceive acoustic differences between speech sounds, leading to problems related to “speech pronunciation” (speech sound difficulties). Another possible consequence is auditory processing difficulties, such as APD.
Let’s understand why…
Unlike the sense of hearing, which is fully mature at birth, auditory processing skills gradually develop during childhood (Moore, 2015). For instance, performance in speech in noise tests improves from 5 to 12 years old (Wilson et al., 2010; Myhrum et al., 2016; Murphy et al., 2019). However, to fully develop those skills, e.g. learning to process those sounds in complex acoustic environments such as in the presence of noise, the child must receive adequate and consistent auditory input in both ears so that the auditory pathways can be fully and healthily developed. The presence of recurrent or persistent OME impacts how the auditory system receives the signal; it might be a “fluctuating signal”, as the level of the hearing loss would change depending on the presence of the fluid, and “asymmetrical”, as the degree of hearing loss might be different in each ear. Both characteristics will lead to inconsistent signals arriving at the auditory pathway and brain, ultimately leading to an abnormal auditory system development. Those physiological differences will lead to clinical implications, such as difficulties with speech understanding in the presence of noise, the most classic APD symptom. Studies have shown that spatial listening skills seem more affected by this specific risk factor, leading to a particular APD condition called Spatial Processing Disorder (Tomlin & Rance, 2014; Graydon et al., 2017).
It is important to note that not necessarily your child will have APD if they have a history of recurrent OME; however, research shows that the chances are higher. A formal Auditory Processing Assessment is required to clarify this question. Therefore, if you suspect that your child might have APD or if you have any concerns about their auditory health, it is important to seek professional help.
For more information about APD and glue ear, check the references below:
Graydon K, Rance G, Dowell R, Van Dun B. Consequences of Early Conductive Hearing Loss on Long-Term Binaural Processing. Ear Hear. 2017 Sep/Oct;38(5):621-627.
Hall JW 3rd, Derlacki EL. Effect of conductive hearing loss and middle ear surgery on binaural hearing. Ann Otol Rhinol Laryngol. 1986 Sep-Oct;95(5 Pt 1):525-30.
Moore DR. (2015). Sources of pathology underlying listening disorders in children. Int J Psychophysiol. 95(2):125-34
Murphy CFB, Hashim E, Dillon H, Bamiou DE. (2019). British children's performance on the listening in spatialised noise-sentences test (LISN-S). Int J Audiol. 58(11):754-760.
Myhrum M., Tvete O. E., Heldahl M. G., Moen I., Soli S. D. (2016). The Norwegian hearing in noise test for children. Ear Hear. 37 80–92.
Nittrouer S, Lowenstein JH. Early otitis media puts children at risk for later auditory and language deficits. Int J Pediatr Otorhinolaryngol. 2024 Jan;176:111801. doi: 10.1016/j.ijporl.2023.111801.
Tomlin D, Rance G. Long-term hearing deficits after childhood middle ear disease. Ear Hear. 2014 Nov-Dec;35(6):e233-42.
Wilson R. H., Farmer N. M., Gandhi A., Shelburne E., Weaver J. (2010). Normative data for the words-in-noise test for 6- to 12-year-old children. J. Speech Lang. Hear Res. 53 1111–1121.
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