Department of Otolaryngology, University of Rochester School of Medicine and Dentistry, 601 Elmwood Ave, Rochester, NY, 14642, USA.
Department of Anesthesiology and Critical Care Medicine, Children's Hospital of Philadelphia, 3401 Civic Center Blvd, Philadelphia, PA, 19104, USA.
Neurotoxicology. 2020 Mar;77:137-144. doi: 10.1016/j.neuro.2020.01.005. Epub 2020 Jan 23.
To determine if auditory function is associated with current long chain polyunsaturated fatty acids (LCPUFA) concentrations in a cohort of young adults who consume oceanic fish with naturally acquired methylmercury (MeHg). We measured participants plasma LCPUFA concentrations (total n-3, total n-6 and the n-6:n-3 ratio) and looked for an association with Auditory Brain Response (ABR) latencies and Otoacoustic Emissions (OAE) amplitudes.
Auditory function of 534 participants from the Seychelles Child Development Study (SCDS) main cohort was examined at 19 years of age. Tests included standard pure-tone audiometry, tympanometry, ABR and both Click-Evoked OAE (CEOAE) and Distortion-Product OAE (DPOAE). Associations of LCPUFA status, measured at the time of examination, and auditory outcomes were examined using covariate-adjusted linear regression models. All models were adjusted for sex, prenatal and current MeHg exposure and hearing status.
LCPUFA concentrations were similar for both sexes and when comparing participants with normal hearing (90.4 %) to those who had a sensorineural hearing loss in one or both ears (9.6 %). When looking at a subset of only hearing impaired participants, LCPUFA concentrations were similar in those participants who had a mild sensorineural hearing loss as compared with participants that had a moderate sensorineural hearing loss. LCPUFA concentrations were not correlated with current hair MeHg. LCPUFA concentrations were statistically significantly associated with only 6 of 174 ABR and OAE endpoints examined. Four of the 6 significant associations were present in only one sex. In female participants as n-6 concentrations increased, the ABR wave I absolute latency increased for a 60 dBnHL 19 click/sec stimulus. For male participants the interwave I-III latencies for a 60 dBnHL 69 clicks/sec stimulus increased as the n-6:n-3 LCPUFA ratio increased and the interwave I-V interval decreased for a 60 dBnHL 39 clicks/sec stimulus as the n-6 concentration increased. For both sexes interwave latencies were prolonged for the III-V interwave interval for an 80 dBnHL 39 clicks/sec as n-3 LCPUFA concentration increased. As the n-3 LCPUFA concentrations increased, the amplitude of the 6000 Hz DPOAE in the right ear increased for both sexes. As the n-6:n-3 ratio increased, the amplitude of the 1500 Hz DPOAE in the left ear decreased for females. The amplitude of the CEOAE was not associated with n-3, n-6 LCPUFA concentrations or the n-6:n-3 ratio.
There was no evidence to suggest LCPUFA status was associated with hearing acuity, ABR latencies or OAE amplitudes, even though our participants tended to have higher LCPUFA concentrations as compared to individuals consuming a more western diet. No association was observed between LCPUFA status and a participants hearing status (normal hearing or hearing loss). Although we found a few associations between current plasma LCPUFA status and ABR and OAE auditory endpoints examined, no clear pattern exists. Some of these associations would be considered detrimental resulting in prolonged ABR latencies or smaller OAE amplitudes, while others would be considered beneficial resulting in shortened ABR latencies or larger OAE amplitudes.
在摄入天然甲基汞（MeHg）海洋鱼类的年轻成年人队列中，确定听觉功能是否与当前长链多不饱和脂肪酸（LCPUFA）浓度相关。我们测量了参与者的血浆 LCPUFA 浓度（总 n-3、总 n-6 和 n-6:n-3 比值），并寻找与听觉脑干反应（ABR）潜伏期和耳声发射（OAE）幅度的关联。
在 19 岁时检查塞舌尔儿童发展研究（SCDS）主要队列中 534 名参与者的听觉功能。测试包括标准纯音听力测试、鼓室图、ABR 以及 Click-Evoked OAE（CEOAE）和 Distortion-Product OAE（DPOAE）。使用协变量调整的线性回归模型，检查 LCPUFA 状况与听觉结果之间的关联，LCPUFA 状况在检查时进行测量。所有模型均调整了性别、产前和当前 MeHg 暴露以及听力状况。
男性和女性的 LCPUFA 浓度相似，在比较听力正常（90.4%）和单侧或双侧感音神经性听力损失的参与者（9.6%）时也是如此。当仅观察听力受损的参与者亚组时，与中度感音神经性听力损失的参与者相比，轻度感音神经性听力损失的参与者的 LCPUFA 浓度相似。LCPUFA 浓度与当前头发中的 MeHg 没有相关性。LCPUFA 浓度与 174 个 ABR 和 OAE 终点中的 6 个仅呈统计学显著相关。这 6 个显著关联中的 4 个仅存在于一种性别中。在女性参与者中，随着 n-6 浓度的增加，60dBnHL 19 次/秒刺激的 ABR 波 I 绝对潜伏期增加。对于男性参与者，随着 n-6:n-3 LCPUFA 比值的增加，60dBnHL 69 次/秒刺激的 I-III 波潜伏期增加，随着 60dBnHL 39 次/秒刺激的 n-6 浓度增加，I-V 间隔减小。对于两性，随着 n-3 LCPUFA 浓度的增加，III-V 间期的 ABR 潜伏期延长。对于 80dBnHL 39 次/秒刺激，右耳的 6000Hz DPOAE 振幅增加。随着 n-6:n-3 比值的增加，左耳 1500Hz DPOAE 的振幅减小，女性的振幅减小。CEOAE 的振幅与 n-3、n-6 LCPUFA 浓度或 n-6:n-3 比值无关。
尽管我们的参与者的 LCPUFA 浓度往往高于摄入更西式饮食的个体，但没有证据表明 LCPUFA 状态与听力敏锐度、ABR 潜伏期或 OAE 幅度相关。没有观察到 LCPUFA 状态与参与者的听力状况（正常听力或听力损失）之间存在关联。尽管我们发现当前血浆 LCPUFA 状态与检查的 ABR 和 OAE 听觉终点之间存在一些关联，但没有明确的模式。其中一些关联可能是有害的，导致 ABR 潜伏期延长或 OAE 幅度减小，而另一些关联可能是有益的，导致 ABR 潜伏期缩短或 OAE 幅度增大。
