Table 4 Summary of previous studies and current results.
From: The biphasic impact of apolipoprotein E ε4 allele on age-related hearing loss
Reference | Study design (Country) | Cohort number | Mean age (Range) | Hearing tests (side) | Hearing loss definition | ApoE ε4 genotype group | Results | Limitations |
|---|---|---|---|---|---|---|---|---|
O’Grady et al. (2007) | Longitudinal cohort study (USA) | 89 | 64 (34–95) | PTA, SA (not mentioned) | ≥ 40 dB HL | allele frequencies | No association | Small cohort |
C. Kurniawan et al. (2012) | Population-based study (Netherlands) | 435 | 85 | Portable PTA (better ear) | > 35 dB HL (1000, 2000, 4000 Hz average) | ε4 (+)/(−) | ε4 genotype is related to hearing loss | Portable audiometer was used |
Dawes et al. (2015) | Candidate gene association study (UK) | 265 | 72 (59–88) | PTA (better ear) | NA | ε4 (+)/(−) | No association | |
Mener et al. (2016) | Prospective observational study (USA) | 1833 | 70–79 | PTA (better ear) | NA | ε4 (+ / +)/(+ /-)/(−/−) | ε4 genotype is related to good hearing | ε4 (+ / +) group had small number (n = 23) and was younger |
Y.Morita et al. (2019) | Cross-sectional survey in prospective cohort study (Japan) | 322 | 71 (60–89) | PTA (better ear) | > 30 dB HL (average frequency between 0.25 and 8 kHz) | ε4 (+ / +)/(+ /−)/(−/−) | No association | |
Sarant et al. (2020) | A cross-sectional study (Australia) | 2006 | 66 | PTA (better ear) | > 25 dB HL (Average 500, 1000, 2000, and 4000 Hz) | ε4 (+ / +)/(+ /−)/(−/−) | No association | ε4 (+ / +) group had small number (n = 35) |
Kim et al. (2021) | A longitudinal cohort study (South Korea) | 1092 | 61 | ICD-10 code | NA | ε4 (+)/(−) | ε4 carrier & male : high risk of hearing loss (OR = 1.90) | No hearing tests |
Present study | Retrospective multicentre study (South Korea) | 1162 | 76 | PTA (better ear) | > 25 dB HL (Average 500, 1000, 2000, and 4000 Hz) | ε4 ( +)/(−) | < 75-year-old: ε4 genotype is related to better hearing ≥ 75-year-old: ε4 genotype is related to worse hearing |
