Longitudinal Changes in Auditory Function Among Veterans with Diabetes

描述（由申请人提供）： 糖尿病（DM）是一种代谢性疾病，可引起微血管和神经系统并发症，影响20%在VA接受治疗的退伍军人。有证据支持糖尿病和听力损失之间的联系。在最近的一项研究中，班布里奇等人（2008）报告称，非DM受试者的听力损失患病率为15%，而DM受试者的听力损失患病率为两倍（30%）。之前，我们证明了糖尿病与听力损失相关，主要发生在50岁以下的退伍军人中。在控制听力后，需要胰岛素的糖尿病年轻退伍军人中存在听觉脑干功能障碍。我们的研究结果是在退伍军人中进行的两项横断面研究中建立的，但并未说明听觉功能障碍随时间的进展或其与DM严重程度或代谢控制措施的关系。他们也没有显示这些变化与语音处理缺陷或生活质量有关的程度。 我们将测量患有糖尿病（DM）的退伍军人的听觉功能的纵向变化，使用针对外周，中枢和认知处理阶段的测试。我们将确定在何种程度上DM相关的变化，这些措施干扰语音交流和日常生活。我们还将确定听觉通路的变化如何与糖尿病的特征和维持相关，以及与其他主要糖尿病并发症如视网膜病变或周围神经病变相关。具体来说，我们将测量当前的听觉功能和糖尿病的严重程度和代谢控制的参与者从我们以前的两项研究，近1100名参与者的池。我们将补充这一组新的参与者从特定类别的DM和听力只使用前瞻性的措施。这种方法将在所有参与者的原始测量后2年和3年产生前瞻性随访数据，并在一些参与者的原始测量后长达15年的回顾性随访数据。最终，我们预见了一项针对糖尿病退伍军人的临床试验，这些退伍军人最有可能从严格的代谢控制干预中受益，其结果是改善了听觉功能。 受试者将根据年龄和听力状况从我们之前的研究中招募或招募，并在4年内进行3次测试。我们将进行外周（纯音听阈，耳声发射）和中枢听觉（听觉脑干反应，P300认知反应）功能的测试。此外，我们将包括听觉工作记忆和排序和言语理解的措施。参与者还将完成问卷调查，以询问生活质量，听觉功能障碍对日常生活的影响，以及DM病史，包括持续时间，治疗史和并发症。根据这些反应和DM的客观指标，我们将构建复合量表，用作小血管或神经类型DM并发症的潜在指标。血糖（HbA 1c）水平将通过手指针刺测定。将使用细丝法进行足神经病变检查，并进行视网膜（眼底）摄影。 在控制了连续测量之间的时间差异后，我们期望发现与没有糖尿病的退伍军人相比，随着时间的推移，糖尿病退伍军人的听觉和认知处理发生更大的变化。我们期望这项工作的结果将表明，在听觉和认知功能的变化的风险取决于糖尿病的严重程度和/或代谢控制。如果是这样的话，适当的干预可能会减轻听力和认知障碍，从而改善许多受DM影响的退伍军人的生活质量。因此，拟议中的研究无可争议地促进了改善我国退伍军人健康和福祉的VA使命。

DESCRIPTION (provided by applicant): Diabetes Mellitus (DM) is a metabolic disease that causes microvascular and neurologic complications and affects 20% of Veterans receiving care at the VA. Evidence supports a link between DM and hearing loss. In a recent study, Bainbridge et al. (2008) reported that the prevalence of hearing loss was 15% for participants without DM, but was double (30%) for those with DM. Previously, we demonstrated that diabetes is associated with hearing loss primarily among Veterans below age 50. After controlling for hearing, auditory brainstem dysfunction was present among younger Veterans with DM requiring insulin. Our findings were established in two cross-sectional studies among Veterans but do not address progression in auditory dysfunction over time or its relationship to measures of DM severity or metabolic control. Nor do they show the extent that these changes relate to speech processing deficits or quality of life. We will measure longitudinal changes in auditory function among Veterans with diabetes mellitus (DM), using tests that target peripheral, central and cognitive stages of processing. We will determine the extent to which DM-related changes in these measures interfere with speech communication and daily living. We will also establish how changes in the auditory pathway relate to the characteristics and maintenance of DM and are linked to other major diabetes complications such as retinopathy or peripheral neuropathy. Specifically, we will measure current auditory function and degree of DM severity and metabolic control on participants from our previous two studies, a pool of nearly 1100 participants. We will supplement this group with new participants from specific categories of DM and hearing using only prospective measures. This approach will yield prospective follow-up data at 2 and 3 years after the original measurements on all participants, and retrospective follow-up data up to 15 years from original measurements for some participants. Ultimately, we foresee a clinical trial for those diabetic Veterans most likely to benefit from a strict metabolic control intervention with the outcome of improved auditory function. Participants will be newly recruited or recruited from our previous studies based on age and audiologic status and tested 3 times over 4 years. We will conduct tests of peripheral (pure tone thresholds, otoacoustic emissions) and central auditory (auditory brainstem responses, P300 cognitive response) function. Additionally, we will include measures of auditory working memory and sequencing and speech comprehension. Participants will also complete questionnaires to query quality of life, impacts of auditory dysfunction on daily living, and DM history, including duration, treatment history and complications. From these responses and objective measures of DM we will construct composite scales, which will be used as potential indicators of small vessel or neural types of DM complications. Blood-sugar (HbA1c) levels will be determined via finger stick. Foot neuropathy tests using the filament method will be conducted, and retinal (fundus) photography will be performed. We expect to find greater changes in auditory and cognitive processing over time in Veterans with DM compared to those without, after controlling for differences in the time between serial measurements. We expect results of this work will suggest that the risk of change in auditory and cognitive function depends on DM severity and/or metabolic control. If so, an appropriate intervention could potentially mitigate impairments of hearing and cognition, leading to improved quality of life for the numerous Veterans affected by DM. Therefore, the proposed study indisputably promotes the VA mission of improved the health and well-being of our nation's Veterans.