The effects of age and gender on laryngeal aerodynamics

A computerized airflow/air pressure analysis system, the Aerophone II Model 6800 (Kay Elemetrics Corp.), was used to assess the effects of age and gender on laryngeal aerodynamics. A sample of 56 male and 53 female normal speaking subjects was divided into six age groups (20-30; 31-40; 41-50; 51-60; 61-70 and 71-80 years). The laryngeal aerodynamic parameters measured included phonatory (mean) flow rate, estimated subglottal pressure, laryngeal airway resistance, phonatory sound pressure level, phonatory power, and phonatory efficiency. Most comfortable phonation, vocal efficiency, and running speech tasks were used to collect the aerodynamic data. Comfortable pitch and loudness levels were used for each of these tasks. Age and gender effects were found for a number of the phonatory (mean) flow rate and phonatory sound pressure level values. Results failed, however, to indicate age or gender effects for the estimated subglottal pressure, laryngeal airway resistance, phonatory power and phonatory efficiency parameters. High intersubject variability was found for the phonatory flow rate, laryngeal airway resistance, phonatory power and phonatory efficiency values. Estimated subglottal pressure values, however, appeared to vary the least among subjects. The results are discussed with respect to factors that might influence laryngeal aerodynamics, such as underlying laryngeal anatomical and physiological age-related changes and gender-related differences. The clinical implications of the findings for the assessment and treatment of individuals with voice disorders using the Aerophone II are also discussed.