Short-term association between road traffic noise and healthcare demand generated by Parkinson’s disease in Madrid, Spain

Objective: To analyse whether there is a short-term association between road traffic noise in the city of Madrid and Parkinson’s disease (PD)-related demand for healthcare.

Methods: Time-series analysis (2008–2009) using variables of analysis linked to emergency and daily PD- related demand for healthcare (ICD-10: G20–G21), namely, PD-hospital admissions (HAs), PD-outpatient visits (OVs) and PD-emergency medical calls in Madrid. The noise pollution measurements used were Leqd, equivalent sound level for the daytime hours (from 8 a.m. to 10 p.m.), and Leqn, equivalent sound level for night time hours (from 10 p.m. to 8 a.m.) in dB(A). We controlled for temperature, pollution, trends and seasons, and used the Poisson regression model to calculate relative risk (RR).

Results: The association between Leqd and HAs was found to be linear. Leqd and Leqn at lag 0.1 and temperature at lags 1 and 5 were the only environmental variables associated with increased PD-related healthcare demand. The RR (lag 0) for Leqd and HA was 1.07 (1.04–1.09), the RR (lag 0) for Leqd and OV was 1.28 (1.12–1.45), and the RR (lags 0.1) for Leqn and emergency medical calls was 1.46 (1.06–2.01). Conclusion: The above results indicate that road traffic noise is a risk factor for PD exacerbation. Measures to reduce noise-exposure levels could result in a lower PD-related healthcare demand.