**6. The burden of environmental noise and adverse health outcome**

The disability weight (DW) is used to rank the priority critical health outcome measures. DWs are ratings that vary between 0 and 1, in which 0 indicates no disability and 1 indicates the maximum amount of disability. The DWs have been proven useful in calculating the burden of disease (**Table 6**).


#### **Table 6.**

*Noise and Environment*

**Critical health outcome**

Cardiovascular disease (*L*den)

Effects on sleep (*L*night)

Annoyance (*L*den)

Cognitive impairment (*L*den)

Hearing impairment and tinnitus (*L*Aeq and *L*AF,max)

*1 (equivalent to death).*

**Critical health outcome measures Justification for selection**

Except for self-reports, these are objective measures of the outcome, affect a large proportion of the population, have important health consequences, and can lead to more severe diseases and/or mortality.

This is the most meaningful, policyrelevant measure of this health outcome. Self-reported sleep disturbances are a very common problem in the general population: they affect quality of life directly and may also lead to subsequent health impediments. Effects on sleep may be in the causal pathway to cardiovascular disease. This measure is not a proxy for physiological sleep quality parameters but is an important

DW for IHD: 0.405 DW for hypertension: 0.117

outcome in its own right. DW for %HSD: 0.07

disease.

DW for %HA: 0.02

comprehension: 0.006

induced hearing loss.

This is the most objective measure of this health outcome. Large proportions of the population are affected by noise annoyance, even at relatively low exposure levels. Annoyance may be in the causal pathway to cardiovascular

This outcome measure is the most meaningful: it can affect vulnerable individuals (children) and has a significant impact later in life. DW for impaired reading and oral

This outcome measure can affect vulnerable individuals (children) and has a significant impact later in life. It is the most objective measure for which there is an ISO standard (ISO, 2013), specifying how to estimate noise-

DW for mild severity level (threshold at 25 dB) for childhood onset: 0.0150

Self-reported or measured prevalence, incidence, hospital admission, or

• ischemic heart disease (IHD) (including angina pectoris and/or myocardial

• Percentage of the population highly sleep-disturbed (%HSD), selfreported, assessed with a standard-

• Cardiac and blood pressure outcome

• Motility measured sleep outcomes in

• Percentage of the population highly annoyed (%HA), assessed with

• Percentage annoyed, preferably assessed with standardized scale

• Reading and oral comprehension,

• Impairment assessed with standard-

• Short- and long-term memory deficit

• Executive function deficit (working

• Permanent hearing impairment, measured by audiometry • Permanent tinnitus

*DW: A disability weight is a weight factor that reflects the severity of the disease on a scale from 0 (perfect health) to* 

*Critical health outcomes, outcome measures identified, and justifications for selection according to the WHO* 

• Polysomnography measured outcomes (probability of additional

measures during sleep

standardized scale

assessed with tests

ized tests

*Environmental Noise Guidelines for the European Region.*

• Attention deficit

memory capacity)

• Sleep disturbance in children

mortality due to:

infarction) • hypertension • stroke

ized scale

awakenings)

adults

**30**

**Table 5.**

*Priority health outcomes and relevant risk increases for setting guideline levels according to the WHO Environmental Noise Guidelines for the European Region.*


#### **Table 7.**

*Important health outcomes and health outcome measures reviewed according to the WHO Environmental Noise Guidelines for the European Region.*

For cardiovascular disease, the DW value (DW: 0.405) specifically applied to acute myocardial infarction in the publication outlining the data sources, 5% increase of relative risk in ischemic heart disease (IHD) and 10% in hypertension. The DWs for high sleep disturbance (DW: 0.07), high annoyance (DW: 0.02), and impaired reading and oral comprehension (DW: 0.006) were developed in the context of calculating the burden of disease from environmental noise. According to the WHO night noise guidelines, there were observed adverse health effects at levels starting from 40 dB *L*night, and self-reported sleep disturbance (HSD) and

annoyance should not exceed 3 and 10% to be health protective, receptively. The DW for hearing impairment was available from the technical paper on the burden of disease from environmental noise; a DW of 0.0150 for moderate severity level "has difficulty following a conversation in a noisy environment, but no other hearing problems." For cognitive impairment, the DW was derived from a very conservative value (DW: 0.006) for noise-related impairment of children's cognition, equivalent to a DW for contemporaneous cognitive deficit in the context of a range of cognitive impairments in children. This impact cannot be predicted accurately [9].

Also, WHO provides a list of the important health outcomes along with the reviewed measures. There was no prioritization of health outcome measures leading to justification of selection, since important health outcomes had less impact on the development of recommendations. In **Table 7**, the health outcomerelated noise indicator was *L*den, and the most common health outcomes were relevant to psychoacoustic problems such as quality of life, well-being, and mental health [20].
