Effect of noise stress on autonomic function tests.

Area of Science:

• Occupational Health
• Autonomic Neuroscience
• Environmental Health

Background:

• Industrial noise exposure is a prevalent occupational hazard.
• Chronic exposure to high noise levels may affect physiological functions.
• The impact of occupational noise on autonomic nervous system (ANS) function requires further investigation.

Purpose of the Study:

• To investigate the effects of occupational noise exposure on autonomic nervous system function in male volunteers.
• To compare autonomic function test results between workers exposed to high noise levels and a control group.

Main Methods:

• 200 male volunteers were divided into a study group (steel industry workers exposed to >80 dB(A) for >8 hours/day for 6 months) and a control group.
• Autonomic function tests were performed, including heart rate and blood pressure monitoring during specific maneuvers (standing, Valsalva, cold pressor test).
• Data were analyzed using the Z test to compare group differences.

Main Results:

• The study group exhibited significantly higher mean resting heart rate and heart rate response to standing (P=0.000).
• Abnormalities were observed in the 30:15 ratio (P=0.002) and Valsalva ratio (P=0.017) in the noise-exposed group.
• Significant increases in diastolic blood pressure response to standing (P=0.000) and Valsalva maneuver (P=0.000), as well as blood pressure after the cold pressor test (P=0.000), were noted in the study group.

Conclusions:

• Occupational noise exposure, particularly in the steel industry, leads to significant alterations in autonomic nervous system function, indicative of increased sympathetic activity.
• Noise exposure acts as a substantial health hazard, necessitating a review and strict adherence to maximum allowable exposure limits.