Modifiable factors explaining improved hearing in Swedish 70-year-olds over four decades: a mediation analysis

Area of Science:

• Audiology
• Gerontology
• Public Health

Background:

• Hearing loss is a significant public health issue, particularly in aging populations.
• Previous studies suggest cohort differences in hearing function among older adults.
• Understanding the factors contributing to these differences is crucial for preventive strategies.

Purpose of the Study:

• To investigate the mediating roles of educational level, occupational group, systolic blood pressure, and smoking in explaining improved hearing in more recently born cohorts of 70-year-olds.
• To analyze cohort differences in hearing using data from the Gothenburg H70 Birth Cohort Studies.
• To assess the direct and indirect effects of cohort on hearing via specific lifestyle and socioeconomic factors.

Main Methods:

• Repeated cross-sectional analysis of two age-homogeneous birth cohorts (1901-1907 and 1944) of 70-year-olds.
• Mediation analyses to examine the influence of education, occupation, smoking, and systolic blood pressure on hearing differences.
• Standardized health examinations including audiometric testing.

Main Results:

• Educational level was the primary mediator of cohort differences in hearing (1.19 dB of 6.16 dB PTA4 difference).
• Occupational group (0.74 dB) and smoking habits (0.28 dB) also played mediating roles.
• Sex-stratified analyses revealed education as the dominant mediator in women, while occupation was more significant in men.

Conclusions:

• Changes in lifestyle and socioeconomic factors, particularly education, occupation, and smoking, contribute to the observed trend of better hearing in recent generations of 70-year-olds.
• These factors are relevant for developing preventive strategies to maintain hearing health in aging populations.
• The findings highlight the importance of addressing socioeconomic and lifestyle determinants of hearing in public health initiatives.