METHODS: We conducted a population-based longitudinal study in Norway using the Trøndelag Health Study (HUNT) from 1996 to 1998 (baseline) and from 2017 to 2019 (follow-up). The sample included 1648 participants with baseline age ≥55 years (42% men, mean age 60 years) and <5 years occupational noise exposure after baseline. We analyzed the association between occupational noise exposure before baseline and mean hearing decline between 1998 and 2018 (20-year decline) at each frequency, adjusted for age, sex, education, and impulse noise exposure before baseline.
RESULTS: Occupational noise exposure before baseline (N = 603) was associated with baseline hearing loss, but not with later accelerated 20-year decline, at any frequency. Noise-exposed persons had less subsequent 20-year decline at 3 kHz than did nonexposed. Restricting the noise-exposed group to persons who also had a baseline Coles notch (hearing thresholds at 3, 4, or 6 kHz of 10 dB or more compared with thresholds at 1 or 2 kHz and 6 or 8 kHz; N = 211), the exposed group showed less 20-year decline at both 3 and 4 kHz, as well as less accelerated 20-year decline at 8 kHz, compared with the nonexposed.
CONCLUSIONS: Our large long-term longitudinal study shows no increased risk of continuing hearing decline after occupational noise exposure has ceased. The finding supports a conclusion that ear damage stops when the noise exposure is ended.
方法:我们从1996年至1998年(基线)和2017年至2019年(随访)在挪威使用Trøndelag健康研究(HUNT)进行了一项基于人群的纵向研究。该样本包括1648名基线年龄≥55岁的参与者(42%的男性,平均年龄60岁)和基线后<5年的职业噪声暴露。我们分析了基线前的职业噪声暴露与1998年至2018年每个频率的平均听力下降(20年下降)之间的关系。根据年龄调整,性别,教育,和基线前的脉冲噪声暴露。
结果:基线前职业噪声暴露(N=603)与基线听力损失相关,但不是随着后来20年的加速下降,在任何频率。暴露于噪声的人随后在3kHz时的20年下降幅度小于未暴露的人。将噪声暴露组限制在也有基线Coles陷波的人(3、4或6kHz的听力阈值为10dB或更高,与1或2kHz和6或8kHz的阈值相比;N=211),暴露组在3和4kHz时显示出20年的下降幅度较小,以及在8kHz时20年的加速下降,与未暴露的相比。
结论:我们的大型长期纵向研究表明,在职业噪声暴露停止后,听力持续下降的风险没有增加。该发现支持以下结论:当噪声暴露结束时,耳朵损伤停止。