Study objectives: To design a national antinoise policy, we need to know the monetary value that people attach to the reduction of sleep disturbance due to road traffic noise.
Principles: Patients with obstructive sleep apnea syndrome (OSAS) controlled by nasal continuous positive airway pressure (nCPAP) underwent one-to-one structured interviews to determine the monetary value of their resultant undisturbed sleep. This was then converted into a value for sleep undisturbed by noise, using a severity ratio.
Setting: Outpatient interviews in 67 OSAS patients (54 males, 28 to 73 years old) managed by the Center for Sleep Medicine, Kantonsspital, St. Gallen, Switzerland.
Materials and methods: The interview questions addressed the outcome and difficulties of nCPAP therapy, the self-rated severity of pretreatment sleep disturbance and self-rated monetary value of sleep improvement. Thirteen OSAS patients who had also experienced noise-related sleep disturbance rated its severity on a visual analogue scale (VAS).
Results: The mean monetary value of nCPAP-controlled sleep disturbance was Swiss francs (CHF) 70/night (CHF1 = US$ 0.877, year end 2004; 25th and 75th percentiles: CHF 35 and CHF 100). Interviewees maintained this high estimate after learning that the actual treatment costs were only approximately 6 CHF/night. A severity ratio ranging from 2.3:1 to 4.7:1 for sleep disturbance resulting from OSAS or from noise was derived from patients' responses and literature. The value of noise-free sleep was CHF 7.45-23.81 per night.
Conclusion: Sleep undisturbed by noise has a remarkably high monetary value for people, which should be considered in political decision-making.