纯音听阈正常糖尿病前期患者畸变产物耳声发射的变化特点

目的 观察纯音听阈正常的糖尿病前期（pre-diabetic）患者畸变产物耳声发射（distortion product otoacoustic emission，DPOAE）情况，探讨其变化特点。方法 根据口服葡萄糖耐量试验（oral glucose tolerance test，OGTT）和纯音测听结果连续入组年龄<60岁的纯音听阈正常的糖尿病前期患者30例，其中，男性13例，女性17例，平均年龄（49.80±8.23）岁，对照组为同期年龄、性别构成接近、血糖结果正常的健康体检人群30例，其中，男性9例，女性21例，平均年龄（46.55±5.09）岁。所有受试者进行内分泌相关检查（包括空腹血糖、2 h血糖、糖化血红蛋白、血脂、尿白蛋白/肌酐等）及畸变产物耳声发射检查，比较两组受试者各频率畸变产物耳声发射反应幅值及异常检出率。结果 糖尿病前期组左、右耳DPOAE反应幅值均低于对照组，其中左耳在0.7、1、1.5、2、3、4 kHz差异有统计学意义（P<0.05），右耳在1.5、2、3、4、6 kHz差异有统计学意义（P<0.05）。在异常检出率方面，糖尿病前期组各频率均高于对照组，在3 kHz差异有统计学意义（P=0.037）。结论 糖尿病前期在纯音测听正常时就已出现耳蜗外毛细胞功能受损，以右耳受损更为显著，存在右耳优势减弱，畸变产物耳声发射较纯音测听敏感性更高。

Analysis of distortion product otoacoustic emission characteristics in pre-diabetic mellitus patients with normal pure tone threshold

Objective To compare the differences of distortion product otoacoustic emission (DPOAE) among pre-diabetic patients with normal pure tone threshold and the controls and to investigate the characteristics of hearing loss in pre-diabetic patients. Methods All participants underwent oral glucose tolerance test(OGTT). Thirty pre-diabetic patients with normal pure tone threshold and younger than 60 years were enrolled with 30 age and sex matched controls. Weight, height, and other general information are collected in all subjects. Laboratory tests including hemoglobin A1C, fasting blood glucose, 2-hour postprandial blood glucose, triglyceride, high density lipoprotein cholesterol, low density lipoprotein cholesterol were carried out. Urine albumin-creatinine ratios were calculated. All subjects underwent DPOAE examination. All relevant parameters including DPOAE amplitude were collected. Results DPOAE amplitude at each frequency in the pre-diabetes group was lower than the control group, with statistical significances at 0.7,1, 1.5, 2, 3, 4 kHz in left ear and 1.5, 2, 3, 4, 6 kHz in right ear (P<0.05). Abnormal detection rate at each frequency in the pre-diabetes group was higher than the control group, with statistical significances at 3 kHz(P=0.037). Conclusion When pure tone threshold is normal, the function of outer hair cells of cochlea have been impaired in the pre-diabetes mellitus. The advantage of the right ear was weakened. The distortion product otoacoustic emission is more sensitive than pure tone audiometry.