Severe hearing loss associated with neurocognitive deficits in childhood cancer survivors
Severe hearing loss among survivors of childhood cancer appeared associated with neurocognitive deficits independent of the neurotoxic therapy they received, according to results of a cross-sectional study published in JAMA Oncology.
Early screening and intervention may identify those at risk for hearing impairment and help maintain neurocognitive function.
“There has been a lot of research on how children who are born deaf can be affected academically and psychosocially, but far less for kids who acquire hearing loss at some point during their childhood,” Johnnie K. Bass, PhD, research audiologist St. Jude Children’s Research Hospital, said in a press release. “Our goal was to report on the prevalence, severity and risk [for] hearing loss in a large cohort of cancer survivors to assess the impact of hearing impairment on neurocognitive function.”
Survivors of childhood cancer remain at risk for chronic morbidities linked to disease and treatment, including hearing loss and neurocognitive deficits.
Bass and colleagues measured hearing and neurocognitive function among 1,520 long-term survivors of childhood cancer (median age, 29.4 years; 53.6% male) who participated in the St. Jude Lifetime Cohort Study.
All participants survived 5 or more years after their original diagnosis. Median time since diagnosis was 20.4 years (interquartile range, 6.1-53.8).
Researchers grouped survivors by hearing sensitivity, including normal hearing (n = 946), mild hearing impairment (n = 221) or severe hearing impairment (n = 353), and stratified them by treatment exposure (platinum chemotherapy only, n = 307; cochlear radiotherapy with or without platinum-based chemotherapy, n = 473; no exposure to treatment, n = 740). They coded hearing outcomes using the Chang Ototoxicity Grading Scale.
The investigators used multivariable log-binomial models, adjusted for age at diagnosis, time since diagnosis, sex and relevant treatment exposures, to study associations between severe hearing impairment and neurocognitive deficits.
Hearing and neurocognitive function served as the primary endpoints.
Results showed higher prevalence of and risk for severe hearing impairment among survivors who received platinum chemotherapy only (34.9%; RR = 1.68; 95% CI, 1.2-2.37) or cochlear radiotherapy (38.3%; RR = 2.69; 95% CI, 2.02-3.57) compared with those who had no exposure (8.8%).
Severe hearing impairment appeared associated with deficits in the following areas compared with normal hearing or mild hearing impairment:
verbal reasoning skills: platinum-only group, RR = 1.93 (95% CI, 1.21-3.08); cochlear radiotherapy group, RR = 2 (95% CI, 1.46-2.75); no-exposure group, RR = 1.11 (95% CI, 0.5-2.43);
verbal fluency: platinum-only, RR = 1.83 (95% CI, 1.24-2.71); cochlear radiotherapy, RR = 1.45 (95% CI, 1.09-1.94); no exposure, RR = 1.86 (95% CI, 1.19-2.91);
visuomotor speed: platinum-only, RR = 3.1 (95% CI, 1.92-4.99); cochlear radiotherapy, RR = 1.4 (95% CI, 1.11-1.78); no exposure, RR = 1.87 (95% CI, 1.07-3.25); and
mathematic skills: platinum-only, RR = 1.63 (95% CI, 1.05-2.53); cochlear radiotherapy, RR = 1.58 (95% CI, 1.15-2.18); no exposure, RR = 1.9 (95% CI, 1.18-3.04).
An inability to identify when hearing impairment or neurocognitive problems began served as a limitation to this study.
“Even patients not exposed to neurotoxic therapies who develop mild hearing deficits can have problems with their neurocognitive skills,” Kevin R. Krull, PhD, faculty member and endowed chair in cancer survivorship at St. Jude Children’s Research Hospital, said in a press release. “This makes it important to identify these patients early and suggest interventions to help improve their hearing and thus their neurocognitive outcomes.”
Considering the potential consequences of unmitigated hearing loss, and with advances in audiologic technology, hearing aids and assistive devices hold promise to obviate the profound lifetime limitations and impairments associated with unrecognized and untreated hearing loss across the spectrum of childhood cancer survivorship, Wendy Landier, PhD, CRNP, associate professor in the division of pediatric hematology-oncology at The University of Alabama at Birmingham, wrote in an accompanying editorial.
“Further study is needed to determine whether neurocognitive deficits identified in childhood cancer survivors with severe hearing impairment can be remediated through audiologic interventions or, more important, whether these neurocognitive deficits could be prevented through early audiologic screening and intervention,” Landier wrote. “Thus, the importance of early identification of hearing deficits, which has always been crucial for optimizing language and communication skills in affected children, may take on new significance as discovery in this area continues. In the meantime, findings highlighted by this study regarding the poor uptake of audiologic interventions among childhood cancer survivors should speak volumes to the clinicians caring for them.”
- Bass JK, et al. JAMA Oncol. 2020;doi:10.1001/jamaoncol.2020.2822.
- Landier W. JAMA Oncol. 2020;doi:10.1001/jamaoncol.2020.2639.