Noise & Health最新文献

Background: No data on voice problems in school teachers in Madinah, which is a key academic hub of Saudi Arabia, is currently available. To the best of our knowledge, no prior cross-sectional study was conducted to assess the prevalence, severity and risk factors of voice problems in this population.

Methods: The Voice Handicap Index-10 (VHI-10) was employed to evaluate the prevalence and severity of voice disorders in teachers from various schools in Madinah. A demographic questionnaire was employed to collect data on established risk factors.

Results: This study of 217 school teachers in Madinah, 19.4% reported experiencing current voice issues. The median score on the VHI-10 was 3 (with an interquartile range of 9), demonstrating significantly higher scores in teachers who were exposed to classroom noise (P = 0.008), who spoke in environments with background noise (P = 0.001) and who reported daily work-related stress (P = 0.021). Clinical factors, including vocal cord paresis (P < 0.001) and corticosteroid use (P = 0.008), were associated with elevated voice handicap scores. Although these symptoms were prevalent, the tendency to seek assistance was minimal. Only 24.0% consulted a specialist, and only 4.8% received therapy.

Conclusion: Voice issues were prevalent in school teachers and were closely associated with classroom noise, vocal strain and a range of clinical complications. Despite the high incidence of these symptoms, the rates of seeking help and participating in therapy were notably low.

Objective: This study aims to evaluate the applicability and limitations of the equal energy hypothesis (EEH) in assessing noise-induced hearing loss (NIHL) and investigate the role of the kurtosis parameter (reflecting noise temporal structure) in assessing NIHL, providing a basis for refining EEH theory.

Materials and methods: A systematic review and meta-analysis were conducted to summarize studies related to EEH, systematically collecting its development, validation, and revision suggestions. The weighted mean difference (WMD) and odds ratio (OR) of hearing loss caused by different types of noise were used to evaluate the role of noise kurtosis in the evaluation of NIHL.

Results: A total of 57 articles were included, containing experimental and cross-sectional studies. Evidence showed significant limitations in the EEH when assessing non-steady noise, leading to an underestimation of NIHL under equal energy conditions. Animal experiments verified a critical level for assessing NIHL when using the EEH, with ranges of 90-135 dB in chinchillas and 108-120 dB in guinea pigs. EEH could be revised in the frequency domain (spectrum) and time domain (e.g., kurtosis). Meta-analysis showed that in animal experiments, WMD for permanent threshold shifts (PTSs) at 2, 4, and 8 kHz (PTS at 2, 4, and 8 kHz) was 3.30 dB (95% confidence interval [95% CI]: 2.22-4.37); in population surveys, OR for high-frequency NIHL was 1.78 (95% CI: 1.36-2.32). Logistic regression analysis confirmed kurtosis as a risk factor for NIHL (P < 0.001). Kurtosis adjustment for cumulative noise exposure and equivalent sound level adequately improved the accuracy of hearing loss estimation.

Conclusion: The EEH's limitations in assessing NIHL caused by non-steady noise can be remedied by adjusting noise energy metrics using kurtosis. Our findings suggest that EEH could be revised as an "equal energy and equal kurtosis hypothesis."

Objectives: This review examines how nighttime noise and irregular schedules influence circadian and endocrine regulation. It introduces a conceptual multilevel model to explore how these exposures may accumulate over time and contribute to long-term health risks.

Methods: A scoping narrative review was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses principles in PubMed, Scopus, Web of Science and Embase (1992-2024), including human studies on nighttime noise and shift work. Eligible studies involved adults and reported circadian, hormonal, metabolic or chronic disease outcomes. Twenty-five studies were synthesised using direction-based vote counting due to heterogeneity because meta-analysis was not feasible. The tally reflected the direction of effects rather than statistical significance. Risk-of-bias assessments informed interpretation, but not exclusion. Findings were integrated into a multilevel model integrating exposure, physiological mediation and cumulative effects.

Results: Nighttime noise and rotating night duties shifted melatonin timing and reduced sleep continuity. Studies reported increased fasting glucose, decreased insulin sensitivity and unfavourable lipid profiles in groups exposed to these work periods. Several investigations described an increase in cardiometabolic load amongst long-term night-duty workers. In the simulation scenarios, the model followed these findings and produced circadian and metabolic changes that increased across repeated exposure cycles.

Conclusions: This review proposes and illustrates a dynamic framework for understanding how nighttime noise and shift work may contribute to circadian and metabolic disruption over time. Its exploratory nature reflects heterogeneous evidence and a scoping design. The findings should be interpreted without causal inference.

Background: Perioperative anxiety and discomfort are common in orthopaedic fracture surgery under regional anaesthesia. Music therapy, a nonpharmacological intervention, may reduce anxiety and improve patient experience; however, its role in this context is underexplored.

Methods: This retrospective cohort study evaluated 240 adults undergoing elective closed limb fracture surgery under regional anaesthesia (January 2023-December 2024). The patients were divided into a Music group (n = 120) receiving perioperative music via headphones and a Control group (n = 120) receiving standard care. Outcomes included preoperative anxiety (State-Trait Anxiety Inventory - State scale [STAI-S]), postoperative pain (Visual Analogue scale), sedative/opioid use (midazolam, fentanyl), vital signs, satisfaction and complications.

Results: The following baseline characteristics were similar for the two groups: age (48.3 ± 13.9 vs. 49.4 ± 15.5 years), gender (55% male vs. 49.2% female), American Society of Anesthesiologists (ASA) status (19.2% vs. 19.2% ASA I, 60.0% vs. 64.2% ASA II, 20.8% vs. 16.7% ASA III). Compared with those in the Control group, postoperative anxiety scores (STAI-S) were lower in the Music group 2 hours after surgery (39.5 ± 7.8 vs. 48.2 ± 9.1, P < 0.01). Their postoperative pain scores were also reduced (2.9 ± 0.9 vs. 4.3 ± 1.3, P < 0.01). The Music group required less midazolam (0.03 ± 0.01 vs. 0.04 ± 0.01 mg/kg) and fentanyl (0.4 ± 0.2 vs. 0.6 ± 0.2 μg/kg; both P < 0.01) and had higher satisfaction (8.4 ± 0.7 vs. 7.2 ± 1.0, P < 0.01). Complication rates were similar (5.0% vs. 6.7%, P = 0.56).

Conclusions: Perioperative music therapy reduced anxiety, pain and sedative/opioid use whilst improving satisfaction in orthopaedic surgery under regional anaesthesia. Music is a safe, low-cost adjunct to enhance perioperative care in awake surgical settings.

Background: The influence of visitor behaviour and sound pressure levels on zoo animals remains unclear.

Objective: This study examined associations between sound pressure levels, visitor numbers and faecal glucocorticoid metabolites (FGCMs) in a male okapi (Okapia johnstoni) at a UK zoo.

Materials and methods: Data were collected across two 5-day periods representing high- and low-visitor seasons, yielding 10 days of acoustic recordings and matching FGCM samples. Acoustic metrics were calculated for the open and closed periods of the zoo (LeqZ, L10Z and L90Z). Statistical analyses included the Wilcoxon and Welch t-tests, as well as Pearson correlations and multiple linear regression models.

Results: LeqZ and L10Z did not differ between seasons, whereas background noise (L90Z) was higher in the low season (t = -4.42, P = 0.005). Sound levels were generally higher during open hours in both seasons. Correlations between visitor numbers and acoustic metrics were weak and non-significant (high season LeqZ × visitors: r = 0.005, P = 0.994; low season: r = -0.347, P = 0.567). FGCM concentrations did not differ between seasons (72a: P = 1.00; 72T: P = 0.37). Regression analyses showed that LeqZOpen positively predicted 72T FGCMs (β = 5.30 ± 1.85, P = 0.02), while visitor numbers negatively predicted 72T (β = -0.04 ± 0.02, P = 0.04). Visitor numbers did not differ between seasons.

Conclusions: Okapi adrenocortical activity appears more responsive to acoustic conditions than to visitor numbers, suggesting noise as the primary stressor. Reducing noise through enrichment or vegetation may improve okapi welfare.

The study of infrasound represents an underexplored domain with profound implications for human health and operational readiness, particularly within civil, defence and security settings. Human exposure to these frequencies is on the rise due to both natural and anthropogenic factors, such as occupational conditions, wind farms, warfare tactics and transportation. This review critically examines the dualistic nature of infrasound by consolidating the current evidence based on qualitative exposure-effect pattern, pathophysiological signatures across animal models and controlled human experiments. By synthesizing current scientific literature, this article highlights the observed effects of infrasound on human well-being, while identifying key research gaps in mechanistic understanding. Moreover, this review underscores the necessity for systematic research aimed at elucidating the cellular and systematic pathways underlying infrasound-induced physiological complexities, and advocates for the development of a robust real-time bio-surveillance system tailored to monitor the exposure related-health outcomes. Additionally, recent technological advancements are explored, with a forward-looking perspective on its integration into next-generation diagnostic modalities and non-invasive therapeutic interventions. By integrating insights from both defence and health perspectives, the review emphasizes on the need to acknowledge infrasound as both a potential health hazard and a promising therapeutic modality, thereby shaping future directions in scientific research, healthcare policy and protective countermeasure development.

Objective: This study aimed to investigate the effects of white noise therapy combined with cognitive behavioural therapy (CBT) on clinical manifestations, psychological stress and sleep quality in patients with depression.

Methods: This study retrospectively analysed 136 patients with mild to moderate depression treated between January 2022 and December 2024. On the basis of their treatment timeline, the patients were divided into conventional group (n = 47, conventional therapy, January-December 2022), CBT group (n = 45, conventional therapy + personalised CBT, January-December 2023) and white noise group (n = 44, conventional therapy + personalised CBT + white noise therapy, January-December 2024). The clinical symptoms [24-item Hamilton Depression Scale (HAMD-24), Stroop test], psychological stress [Perceived Stress Scale (PSS-10), Gross Emotion Regulation Questionnaire (ERQ)], sleep quality [Pittsburgh Sleep Quality Index (PSQI)], cognitive fusion level [Cognitive Fusion Questionnaire (CFQ-F)], hope level [Herth Hope Index (HHI)] and experiential avoidance degree [Acceptance and Action Questionnaire-II (AAQ-II)] were compared before and 12 weeks post-treatment.

Results: Compared with pre-therapy levels, statistically significant improvements at 12 weeks were observed for all three groups (P < 0.05). These included reductions in HAMD-24 scores, Stroop mean reaction time, PSS-10 scores, ERQ suppression subscale scores, PSQI scores and AAQ-II scores, along with increases in Stroop correct responses, ERQ reappraisal subscale scores, CFQ-F scores and HHI scores. Post-therapy between-group comparisons revealed that the white noise group exhibited superior outcomes versus both the conventional and CBT groups across all metrics, while the CBT group outperformed the conventional group on all assessment parameters (P < 0.05).

Conclusion: The findings of this retrospective study suggest that white noise therapy combined with CBT may have positive effects on patients with mild to moderate depression, including improvements in clinical symptoms, psychological stress response and sleep quality. These benefits were demonstrated through reduced depression severity, increased use of cognitive reappraisal strategies, enhanced cognitive fusion, reduced experiential avoidance and elevated hope levels.

Objective: Sleep is a crucial behavioral determinant of physical and psychological well-being. With the rapid urbanization of China, noise pollution has become a growing concern, and its impact on sleep has raised substantial public health attention. This study aims to investigate the potential non-linear relationship between environmental noise and individual sleep duration, and the moderating roles of urban green space and city size.

Methods: We conducted a longitudinal analysis using data from the China Health and Retirement Longitudinal Study. City-level noise exposure was quantified using the Baidu Noise Index, a novel approach in this context. Data on urban population and green space coverage were obtained from the National Bureau of Statistics of China. Fixed-effects regression models were employed to estimate the impact of noise on sleep duration, and moderation analysis was applied to explore the roles of green space and city size.

Results: An inverted U-shaped association was observed between noise levels and sleep duration (linear β = 0.746, P < 0.001; quadratic β = -0.955, P < 0.001), with an inflection point at 0.391 [95% confidence interval (CI): [0.320, 0.566]]. Moreover, this inverted U-shaped pattern was attenuated in cities with higher green space coverage (quadratic interaction β = 0.822, P < 0.05) and larger population (quadratic interaction β = 1.072, P < 0.001).

Conclusion: This study underscores the multifaceted relationship between noise exposure and sleep duration, providing a theoretical foundation for urban planning and health policy formulation, particularly in optimizing urban sound environments and promoting green space development.

Objective: This study aimed to examine the effects of music therapy combined with noise reduction technology on anxiety and pain perception in dental patients.

Methods: Clinical records of 148 edentulous patients receiving dental implantation from April 2022 to April 2025 were retrospectively reviewed. Groups were stratified by institutional protocol timelines: conventional group (n = 50, standard care only, April 2022-June 2023), music group (n = 49, standard care plus music therapy, July 2023-June 2024) and noise reduction group (n = 49, standard care, music therapy and active noise control, July 2024-April 2025). Comparative metrics included pre-therapy versus post-therapy anxiety [Modified Dental Anxiety Scale (MDAS) and State Anxiety Inventory (S-AI)]; intraoperative pain perception [Visual Analogue Scale (VAS)] during osteotomy preparation, implant placement and gingival suturing and perioperative physiological parameters [heart rate (HR) and systolic/diastolic blood pressure (SBP/DBP)] at 30 minutes preoperatively, during implant placement and during suturing.

Results: Compared with pre-therapy baselines, all groups exhibited reduced MDAS and S-AI scores post-therapy (P < 0.05), with the noise reduction group demonstrating lower scores than the music and conventional groups, and the music group had lower values than the conventional group (P < 0.05). VAS scores during osteotomy, implant placement and suturing were lower in the noise reduction group than in the other groups (P < 0.05), whereas the music group showed reduced scores versus the conventional group at all surgical phases (P < 0.05). At 30 minutes before the operation, elevated HR/SBP/DBP occurred during implant placement/suturing in all groups (P < 0.05), with the noise reduction group maintaining lower levels than the two other groups, and the music group demonstrated lower values than the conventional group during both surgical phases (P < 0.05).

Conclusion: The integration of music therapy with noise reduction technology may alleviate anxiety and pain perception in dental implant patients, potentially attenuating perioperative physiological stress responses. However, as a retrospective investigation, these findings reflect associative trends requiring validation through prospective randomised controlled trials.

Background: High noise levels during daytime work may cause sleep disturbances amongst workers, but research findings are inconclusive so far.

Objective: This study aims to compare sleep amongst workers exposed to high and low daytime noise during work in a developing country, where workplaces often have high noise levels.

Methods: A cross-sectional study was conducted amongst 181 metal industrial workers (high-noise-exposed workers) and 72 office cleaners (low-noise-exposed workers) in Tanzania. The average noise levels were 97.9 and 76.6 dBA for the high- and low-noise-exposed workers, respectively. An interview-based questionnaire was used to collect data on sociodemographic characteristics, sleep variables, the Epworth sleepiness scale (ESS) and the Bergen insomnia scale (BIS). Data were analysed using descriptive statistics, t-tests, Kruskal-Wallis tests, Pearson chi-square tests and logistic regression analysis.

Results: The mean BIS score for high-noise-exposed workers was 13.2, with 40.3% reporting insomnia and 39.8% reporting excessive daytime sleepiness (ESS ≥ 11). The low-noise-exposed workers had a mean BIS score of 15.4, with 51.4% reporting insomnia and 41.7% reporting excessive daytime sleepiness. The crude odds ratio (OR) of insomnia when exposed to high noise was 1.56 (95% CI = 0.90-2.718, P = 0.111), and the crude OR for excessive daytime sleepiness was 1.08 (95% CI = 0.62-1.88, P = 0.782). Insomnia and daytime sleepiness were not different between groups when adjusting for age, marital status, education, smoking, alcohol, coffee consumption and daytime rest periods.

Conclusion: No differences were found between daytime high- and low-noise-exposed workers in relation to self-reported sleep variables. The results must be interpreted with caution due to the use of self-reports and possible unmeasured confounders.