Environmental noise pollution and 24-hour blood pressure variability: a cross-sectional analysis in urban industrial zones

The noise pollution of the kind experienced in urban industrial settlements, as one of the major stressors, has negative effect on cardiovascular health, but its association with 24-hour blood pressure variability has been poorly investigated. In this cross-sectional study, an effort was made to assess the relationship between noise pollution and blood pressure variability in 400 urban industrial settlement residents of Uzbekistan. Blood pressure measurements were collected using ambulatory blood pressure monitoring (ABPM) and noise levels with calibrated decimeters (Leq) for 24 hours. Results showed the noisy group (Leq 62.7–72.4 dB) had higher systolic and diastolic blood pressures (132.5 vs. 128.7 mmHg and 82.3 vs. 79.8 mmHg) and higher blood pressure variability (systolic standard deviation 14.8 vs. 12.9 mmHg) compared to the low-noise group. The prevalence of non-dipping (nocturnal BP fall of <10%) was 60% in the noisy group (odds ratio 2.25) versus 40% in the low-noise group. Subgroup analysis identified elderly individuals, women, and smokers as most vulnerable to noise. Increased cortisol (15.2 vs. 13.5 μg/dL) and reduced heart rate variability in the noisy group reconfirmed physiological stress. These findings stress the need to reduce noise in industrial areas for improved cardiovascular health and suggest policies such as the introduction of noise barriers. Longitudinal studies are necessary to determine these relationships.