Industrial noise exposure, noise annoyance, and serum lipid levels in blue-collar workers–the cordis study

Chronic noise exposure may constitute a risk factor for cardiovascular disease, but the exact mechanism is unclear. The authors studied the association between industrial noise exposure, noise annoyance, and serum lipid/lipoprotein levels in male (n = 1 455) and female (n = 624) blue-collar workers. The authors found that young men (i.e., ≤ 44 y of age) exposed to high noise levels (≥ 80 dB[A]) had higher total levels of cholesterol (p =.023) and triglycerides (p =.001), as well as a higher cholesterol ratio (p =.038), than men exposed to low noise levels, even after controlling for confounding variables. In women or in older (> 45 y) men, noise did not affect serum lipid/lipoprotein levels. The authors found no interaction between noise exposure level and noise annoyance (except for high-density lipoprotein in women). However, noise annoyance covaried independently with total cholesterol (p =.022) and high-density lipoprotein (p =.0039) levels in young men and with total cholesterol (p =.035), triglyceride (p =.035), and high-density lipoprotein levels in women (under high noise exposure conditions) (p =.048) levels in women. Noise annoyance and noise exposure levels had an additive effect on cholesterol levels. Young men who scored high on both variables had a 15-mg/dl higher mean cholesterol level (95% confidence interval [CI] = 7.2, 22.8; p =.0003) than those who scored low on both variables; in women, the corresponding difference was 23 mg/dl (95% CI = 1.5, 42.9; p =.019). The authors concluded that the examination of serum lipid/lipoprotein levels may be useful in studies of the health effects of noise, and particular attention should be paid to noise-annoyed individuals.