title: Deterioration of Speech Recognition Ability Over a Period of 5 Years in Adults Ages 18 to 70 Years: Results of the Dutch Online Speech-in-Noise Test.
abstract: OBJECTIVE
  The first aim of the present study was to determine the change in speech recognition in noise over a period of 5 years in participants ages 18 to 70 years at baseline. The second aim was to investigate whether age, gender, educational level, the level of initial speech recognition in noise, and reported chronic conditions were associated with a change in speech recognition in noise.
  
  
  METHODS
  The baseline and 5-year follow-up data of 427 participants with and without hearing impairment participating in the National Longitudinal Study on Hearing (NL-SH) were analyzed. The ability to recognize speech in noise was measured twice with the online National Hearing Test, a digit-triplet speech-in-noise test. Speech-reception-threshold in noise (SRTn) scores were calculated, corresponding to 50% speech intelligibility. Unaided SRTn scores obtained with the same transducer (headphones or loudspeakers) at both test moments were included. Changes in SRTn were calculated as a raw shift (T1 - T0) and an adjusted shift for regression towards the mean. Paired t tests and multivariable linear regression analyses were applied.
  
  
  RESULTS
  The mean increase (i.e., deterioration) in SRTn was 0.38-dB signal-to-noise ratio (SNR) over 5 years (p < 0.001). Results of the multivariable regression analyses showed that the age group of 50 to 59 years had a significantly larger deterioration in SRTn compared with the age group of 18 to 39 years (raw shift: beta: 0.64-dB SNR; 95% confidence interval: 0.07-1.22; p = 0.028, adjusted for initial speech recognition level - adjusted shift: beta: 0.82-dB SNR; 95% confidence interval: 0.27-1.34; p = 0.004). Gender, educational level, and the number of chronic conditions were not associated with a change in SRTn over time. No significant differences in increase of SRTn were found between the initial levels of speech recognition (i.e., good, insufficient, or poor) when taking into account the phenomenon regression towards the mean.
  
  
  CONCLUSIONS
  The study results indicate that hearing deterioration of speech recognition in noise over 5 years can also be detected in adults ages 18 to 70 years. This rather small numeric change might represent a relevant impact on an individual's ability to understand speech in everyday life.
authors.affiliation: 1Department of Otolaryngology-Head and Neck Surgery, Section Audiology, VU University Medical Center and EMGO Institute for Health and Care Research, Amsterdam, The Netherlands; 2Department of Epidemiology and Biostatistics, VU University Medical Center and EMGO Institute for Health and Care Research, Amsterdam, The Netherlands; and 3Phonak AG, Science and Technology, Stäfa, Switzerland.
authors.forename: Mariska
authors.initials: M
authors.lastname: Stam
authors.forename: Cas
authors.initials: C
authors.lastname: Smits
authors.forename: Jos W R
authors.initials: JW
authors.lastname: Twisk
authors.forename: Ulrike
authors.initials: U
authors.lastname: Lemke
authors.forename: Joost M
authors.initials: JM
authors.lastname: Festen
authors.forename: Sophia E
authors.initials: SE
authors.lastname: Kramer
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000375:Aging / Q000502:physiology*; D001302:Audiometry, Speech; D002908:Chronic Disease / Q000453:epidemiology; D015331:Cohort Studies; D004522:Educational Status; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009426:Netherlands / Q000453:epidemiology; D011446:Prospective Studies; D012737:Sex Factors; D059629:Signal-To-Noise Ratio; D013067:Speech Perception / Q000502:physiology*; D055815:Young Adult