Table A55.
Summary of findings table for the association between road traffic noise exposure at home and the change in systolic blood pressure in children.
| Question | Does Exposure to Road Traffic Noise Affect Blood Pressure | |||
|---|---|---|---|---|
| People | Children (boys and girls) | |||
| Setting | Residential setting: Children (aged 6–11 years) living in cities in The Netherlands, the United Kingdom, Germany, Croatia, Serbia and the United States of America | |||
| Outcome | Change in systolic blood pressure (mmHg) | |||
| Summary of findings | Change in systolic blood pressure level per 10 dB increase in road traffic noise level (LDEN) | 0.08 (95% CI: −0.48–0.64) mmHg | ||
| Number of participants (# studies) | 4197 (6) | |||
| Number of cases | NR | |||
| Rating | Adjustment to rating | |||
| Quality assessment | Starting rating | 6 cross-sectional studies # | 2 (low) | |
| Factors decreasing confidence | Risk of bias | Serious a | Downgrading | |
| Inconsistency | Serious b | Downgrading | ||
| Indirectness | None c | No downgrading | ||
| Imprecision | Serious d | Downgrading | ||
| Publication bias | NA e | No downgrading | ||
| Factors increasing confidence | Strength of association | NA f | No upgrading | |
| Exposure-response gradient | Evidence of a non-significant exposure-response gradient f | No upgrading | ||
| Possible confounding | No conclusions can be drawn g | No upgrading | ||
| Overall judgement of quality of evidence | 0 (very low) | |||
# Since only cross-sectional studies were available, we started with a grading of “low” (2); a The quality of the studies was judged as low, since response rates in both studies were higher than 60% and because of the difficulty to judge the quality of the blood pressure measurements. Also studies were not always able to adjust for confounding or were able to attribute individual exposure estimates; b Results across studies differed in the magnitude and direction of effect estimates (see Figure 9.1 of the complete review). This was not confirmed by the results of the heterogeneity analysis, demonstrating only “low” heterogeneity (I2residual = 8.9%); c The studies assessed population, exposure and outcome of interest; d We considered the results to be imprecise: The standard deviation of the reported effect size was larger than the mean difference in blood pressure; e Since the number of available effect estimates was less than 10, it was not possible to test for publication bias or small study bias; f Three of the evaluated studies found a harmful effect of noise. There was evidence of a non-significant exposure-response gradient: after combining the results of the evaluated studies, we found a non-significant effect size of 0.08 mmHg per 10 dB. The noise range was ~35–80 dB. This means that if the road traffic noise level increases from 35 to 80 dB, the blood pressure increased with 0.36 mmHg; g We were not able to draw any conclusions whether possible residual confounders or biases would reduce our effect estimate.