Extra-auditory effects of noise exposure in school workers and preventive measures. A systematic review

OBJECTIVE: Noise is still today one of the main causes of occupational diseas- es; in fact, in Italy in the three-year period 2019- 2022, hearing loss represented 15% of all occu- pational diseases recognized by the National Institute for Insurance against Accidents at Work. The extra-auditory effects related to noise expo- sure also require particular attention, because they can interfere with mental activities that re- quire concentration, memory and ability to deal with complex problems, causing sleep and learn- ing disorders. For this reason, acoustic comfort is considered a fundamental requirement for ob- taining an optimal degree of well-being in closed environments. In schools, a high degree of noise pollution not only makes it difficult for students to listen and learn, but also affects school workers. The aim of this study was to perform a systemat- ic review of international literature and analysis of the preventive measures of extra-auditory effects among school workers. MATERIALS AND METHODS: The presenta- tion of this systematic review is in accordance with the PRISMA statement. The methodologi- cal quality of the selected studies was assessed with specific rating tools (INSA, Newcastle Otta- wa Scale, JADAD, JBI scale and AMSTAR). On- ly publications in English were selected. No re- strictions were applied for the publication type. We excluded articles not concerned with the ex- tra-auditory effects of noise exposure in school workers and preventive measures, findings of less academic significance, editorial articles, in- dividual contributions, and purely descriptive studies published in scientific conferences. RESULTS: Online research indicated 4,363 references: PubMed (2,319), Scopus (1,615) and Cochrane Library (429) have been consulted; 30 studies were included in this review (5 narrative or systematic reviews and 25 original articles). Regarding the scores of narrative reviews, the INSA score showed an average and a median value of 6.5, thus indicating an intermediate/high quality of the studies. Regarding the scores of systematic reviews, the AMSTAR score showed an average of 6.7 and a median and a modal val- ue of 6, thus indicating a high quality of the stud- ies. The scores assigned to the original articles have an average and median value of 7 and a modal value of 6 and this demonstrates an inter- mediate/high quality of the studies. CONCLUSIONS: We can assume that, as it is highlighted by this study, to date these con- sequences are not considered at the legisla- tive level for the protection of exposed workers. The extra-auditory effects impacting health af- terward environmental noise exposure are ma- ny and widespread. Therefore, there is a need for interventions to be carried out by institutions and that the physician of the schools, during health surveillance, investigates the effects and clinical manifestations, in order to prevent disor- ders and deficits highlighted by our study.