# Night-Time Exposure to Road, Railway, Aircraft, and Recreational Noise Is Associated with Hypnotic Psychotropic Drug Dispensing for Chronic Insomnia in the Paris Metropolitan Area

## TL;DR

Night-time noise from traffic and recreation in Paris is linked to higher use of sleep medications, especially among older people and those in poorer areas.

## Contribution

This study is the first to link multiple sources of night-time noise to hypnotic drug use for chronic insomnia at a large urban scale.

## Key findings

- Road noise had the strongest association with increased hypnotic drug dispensing.
- Effects were greater for older adults, women, and socioeconomically deprived populations.
- Over 75% of Paris residents are exposed to road noise exceeding WHO guidelines.

## Abstract

Urban environmental noise represents a major public health issue contributing to chronic sleep disturbances, mainly from road, aircraft, and railway traffic. Night-time recreational noise from cafés, bars, and restaurants has emerged as a frequent source of sleep complaints but remains poorly understood, along with the influence of sociodemographic and economic factors. We addressed this gap by conducting a large-scale ecological study across the Paris Metropolitan Area (~10.5 million inhabitants) examining associations between the Average Energetic Index of night-time noise (AEI Ln) from road, aircraft, railway, and recreational sources and the prevalence of adults aged 18–79 reimbursed for hypnotic psychotropic drugs prescribed for chronic insomnia between 2017 and 2019, stratified by sex, age, and socioeconomic status. The AEI Ln represents the population-weighted average energy noise level within each territory at night (22:00–06:00 in France), calculated at the IRIS level (~2487 inhabitants per IRIS). The dispensing of hypnotic psychotropic drugs concerned 513,276 inhabitants (65.4 per 1000 inhabitants [‰]) on average per year. About 8 million inhabitants (75.7%) are exposed to night-time road traffic noise exceeding WHO health guidelines, followed by railway (~1.2 million, 11.6%), recreational (~1.2 million, 11.5%), and aircraft noise (~1.0 million, 9.8%). Each 5 dB(A) increase in AEI Ln was significantly associated (p < 0.001) with higher dispensing of hypnotic psychotropic drugs, strongest for road noise (+1.0‰), followed by recreational (+0.8‰), aircraft (+0.5‰), and railway noise (+0.3‰). Effects were significantly greater among individuals aged >50 (+8.3‰), women (+2.0‰), and those in the most socioeconomically deprived areas (+2.5‰). These results support proactive public policies aimed at reducing noise from transportation and recreational activities in densely urban areas to mitigate chronic insomnia.