Abstract
Introduction
The prevalence of sleep difficulties from wind farm noise (WFN) compared to road traffic noise (RTN) or other sources is unknown. This study investigated the prevalence, severity and source of sleep difficulties in WFN, RTN and quiet rural exposure areas.
Methods
Geographic sampling and computer assisted telephone interviews were used to evaluate sleep difficulties (falling or staying asleep, waking too early, or feeling unrefreshed) attributed to RTN, WFN or non-WFN and RTN related factors using 0–4 scales (none, mild, moderate, severe, very severe). Three groups were sampled; WFN exposed (n=38–84 in five 2 km bands <10 km from a wind farm; total 372), RTN exposed (n=87 <800 m from a busy road >50,000 vehicles/day) and quiet rural controls (n=83). Preliminary prevalence estimates and odds of moderate-to-very severe sleep difficulties attributed to RTN, WFN or other sources were evaluated.
Results
Few WFN exposed respondents attributed sleep difficulties to WFN (0.8%) compared to moderate-to-very severe difficulties from RTN (2.2%) or other sources (16.1%). Sleep difficulties were higher in RTN exposed (17.2%) compared to quiet (6% OR[95%CI] 4.1[1.3–13.0]) or WFN exposed (OR[95%CI] 9.5[3.9–23.3]) rural areas. Sleep difficulties attributed to other sources were not different between groups (Chi² p=0.054), but tended to be higher in urban RTN exposed residents (26.4%).
Conclusions
Preliminary findings do not support more prevalent sleep difficulties in WFN compared to RTN exposed or quiet rural area residents. Given low rates of WFN-attributed sleep difficulties, larger and/or more sensitive studies remain warranted to further clarify potential WFN effects on sleep.