Table 2

Selected studies investigating the prevalence of hearing loss in cystic fibrosis (CF)

AuthorStudy methodsDefinition of HIResults
Forman-Franco et al, 197949PTA using frequencies 250, 500, 1000, 2000, 4000, 8000 Hz. Recruited from a CF clinic (n=80)Air conduction thresholds for ≥2 frequencies >25 dB1/80 (1%) had HI
Pedersen et al, 198711PTA (frequency range 125–8000 Hz). High-frequency audiogram from 4000–20 000 Hz. All patients had chronic P aeruginosa (n=42)Threshold increased by ≥15 dB in one or both ears at two or more adjacent frequencies2/42 patients (5%) had high-frequency HI. Both patients had normal thresholds <8000 Hz
Mulheran et al, 200130PTA over frequencies 250–8000 Hz. High-frequency PTA over 10 000–16 000 Hz (n=70)≥2 thresholds in either ear of ≥20 dB or one frequency of ≥25 dB over the frequency range 250–8000 Hz17% had HI
Conrad et al, 200840Annual audiometric assessment of patients at two CF clinics with PTA over frequency range 1000–8000 Hz. DPOAE were measured over the frequency range 841–7996 Hz (n=153)Either one PTA threshold >25 dB or abnormal DPOAE thresholds50.8% had abnormal hearing
  • DPOAE, distortion product otoacoustic emissions; HI, hearing impairment; PTA, pure tone audiogram.