Long-term road traffic noise exposure is associated with an increase in morning tiredness.

This study investigates the association between night time road traffic noise exposure (L(night)) and self-reported sleep problems. Logistic regression was performed in a large population based cohort study (GLOBE), including over 18 000 subjects, to study the association between exposure at the dwelling facade and sleep problems. Measures of sleep problems were collected by questionnaire with two questions: "Do you in general get up tired and not well rested in the morning?" and "Do you often use sleep medication or tranquilizers?" After adjustment for potential confounders, a significant association was found between noise exposure and the risk of getting up tired and not rested in the morning. Although prevalence of medication use was higher at higher noise levels compared to the reference category (L(night)<35 dB), after adjustment for covariates this association was not significant. Long-term road traffic noise exposure is associated with increased risk of getting up tired and not rested in the morning in the general population. This result extends the earlier established relationship between long-term noise exposure and self-reported sleep disturbance assessed with questions that explicitly referred to noise and indicates that road traffic noise exposure during the night may have day-after effects.