Study On The Relationship Between Renal Injury And Hearing Impairment In Type 2 Diabetic Patients

Objective:Diabetes is a group of metabolic diseases characterized by high blood sugar,manifested as chronic hyperglycemia,protein and fat metabolism disorders,which can cause multiple organ damage and dysfunction,leading to a series of clinical complications,including cardiovascular and cerebrovascular macrovascular disease and microvascular disease.Renal impairment caused by diabetes mellitus is one of the most important complications of diabetes,and urinary microalbumin can occur early in diabetes.At the same time,diabetes-induced hearing loss was paid more and more attention recently,with more and more related studies.But the relationship between renal injury and hearing loss in diabetics reported little.The aim of this study was to evaluate the changes in hearing function in patients with type 2 diabetes mellitus(T2DM)combined with different contents of urinary microalbumin,and to discuss the relationship between basic clinical indexes and hearing loss,including urinary microalbuminuria(U-MA),glycosylated hemoglobin A1C(HbA1C),urea nitrogen(BUN),serum creatinine(Cr),triglyceride(TG),cholesterol(CHOL),low/high density lipoprotein cholesterol(LDL-C/HDL-C),Homocysteine(Hcy),Cystatin C(Cys-C),and uric acid(UA),providing theoretical basis for the relationship between diabetic nephropathy and hearing impairment.Methods:Thirty cases of T2DM complicated with urinary microalbumin(T2DM early nephropathy group),30 cases of T2DM combined with clinical albuminuria(T2DM clinical nephropathy group)and 20 healthy subjects were collected in this study.Determination of sex,age,body mass index(BMI),HbA1C,BUN,Cr,CHOL,TQ LDL-C/HDL-C,Hcy,Cys-C,UA,fundus and nerve conduction were detected and recorded.Pure tone audiometry,auditory brainstem response(ABR),otoacoustic emission and cochlear electrogram were assayed in patients with T2DM early nephropathy group,T2DM clinical nephropathy group,and healthy control group,to study the status of hearing function and the location of hearing impairment in diabetic patients.Results:1.Results of clinical basic indicators detectionSignificant differences could be found in BMI,U-MA,HbA1C,BUN,Cr,Hey,Cys-C and UA in the control,T2DM early nephropathy and T2DM clinical nephropathy groups(*P<0.05).While TQ CHOL,LDL-C and HDL-C were not statistically significant(P>0.05).Compared with the control group,BMI,U-MA,HbA1C,Cr,Hey of T2DM early nephropathy group and clinical nephropathy group were significantly higher,and the levels of BUN,Cys-C and UA in T2DM clinical nephropathy group were significantly higher than those in control group(*P<0.05).While,levels of BUN,Cys-C and UA in T2DM patients with early nephropathy group were higher than those in control,but with no statistically significance(P>0.05).In addition,BUN,Cr,Hcy,Cys-C and UA were significantly increased in T2DM clinical nephropathy group compared with T2DM early nephropathy group(#P<0.05).2.Analysis of retinopathy and peripheral neuropathyRetinopathy test results found that in healthy control group retinal normal accounted for 19/20,only 1 case of eyes with the lesion(1/20),and no monocular disease(0/20).In T2DM early nephropathy group,retinal normal accounted for 15/30,3 cases of monocular lesions(3/30),and 12 cases of both eyes lesion(12/30).In T2DM clinical nephropathy group,retinal normal accounted for 11/30,1 cases of monocular lesions(1/30),and 18 cases of both eyes lesion(18/30).The results of peripheral neuropathy showed that the proportion of reduced nerve conduction in each group was 15%in healthy control group,40%in T2DM group and 20%in T2DM clinical nephropathy group,including left and right median nerve conduction slowing,left and right tibia,Bilateral slow down and so on.3.Pure tone audiometry resultsCompared with the control group,there was no significant change in the results of the left ear and right ear in the low frequency(250 Hz and 500 Hz)in both T2DM early nephropathy group and T2DM clinical nephropathy group.However,the thresholds of left ear and right ear of T2DM early nephropathy group and T2DM clinical nephropathy group were significantly increased from 1000 Hz(*P<0.05),suggesting that hearing loss was high in patients with diabetes mellitus.The hearing thresholds were(15.25 ± 3.34)dB,(32.33 ± 8.57)dB and(46.33 ± 6.79)dB in the left ear,and(11.8 ± 2.93)dB,(29.5 ± 7.34)dB and(47.17 ± 6.15)dB in the right ear of the control group,T2DM early nephropathy group and T2DM clinical nephropathy group,respectively.At the same time,the thresholds of left ear and right ear in patients with T2DM clinical nephropathy were significantly higher than those in T2DM patients with early nephropathy(P<0.05),suggesting that high-frequency hearing loss was aggravated in patients with severe renal impairment.4.ABR test resultsThe ? wave,? wave,? wave and latent stage ?-?,?-? and ?-? of left ear and right ear of T2DM group were significantly delayed compared with the control group(*P<0.05).To further compare the ABR test results of left ear and right ear of T2DM patients with early nephropathy and T2DM clinical nephropathy,we found that the left ear of patients with T2DM clinical nephropathy was was significantly delayed in latent stage ?-?,?-? and ?-? compared with T2DM patients with early nephropathy(#P<0.05).Right ear showed significantly delayed in the latent period III wave,V wave and latent stage ?-?,?-? T2DM early kidney disease group(#P<0.05).The latency of V wave of the left and right ear also showed delayed in T2DM clinical nephropathy group,with the latency of the left ear and right ear was(6.2 ± 0.42)ms and(6.24 ± 0.40)ms.5.Distortion product otoacoustic emission(DPOAE)test resultsThe hearing loss of left ear and right ear at each frequency(0.5,0.75,1.0,1.4,2.0,3.0,4.0,6.0,8.0 kHz)was followed by T2DM clinical nephropathy group>T2DM early nephropathy group>control group.Especially in the middle and high frequency(1.0-4.0 kHz),the difference between the groups reached largest,indicating that the hair cells accounted the most serious damage in the middle and high frequency(1.0-4.0 kHz),and with the degree of renal injury increased,the outer hair cell function damage gradually increased,especially in the middle and high frequency(1.0-4.0 kHz).6.Analysis of ECochG resultsThe hearing of left and right ear was compared in health control group,T2DM early nephropathy group,T2DM clinical nephropathy group,based on the principle that SP/AP<0.4 as normal,SP/AP>0.4 as abnormal.The results showed that the ratio of left ear hearing abnormality was 15%in healthy control group,53.33%in T2DM early nephropathy group and 86.67%in T2DM clinical nephropathy group.Right ear hearing abnormalities were 20%for healthy controls,50%in T2DM patients with early nephropathy,and 86.67%in T2DM patients with clinical nephropathy,suggesting that with the increase of kidney damage in diabetic patients,cochlear electrogram test results of the normal left and right ear decreased significantly,the abnormal proportion was significantly higher.Conclusions:1.Levels of BMI,U-MA,HbA1C,Cr,Hcy,BUN,Cys-C and UA were significantly increased in DM patients with renal injury,especially for BUN,Cys-C and UA,and retinopathy and peripheral neuropathy significantly increased,suggesting more severe kidney injury.2.T2DM patients with renal injury showed increased hearing threshold in high frequency conditions(4000-8000 Hz),the degree of hearing loss increased with the degree of renal damage.3.T2DM patients with renal injury showed more serious outside hair cell dysfunction under middle and high frequency(1000-4000 kHz),and the degree of hearing loss increased with the degree of renal damage.4.T2DM patients with renal injury showed more associated cochlear water,which may be responsible for the hearing loss of high frequency(4000-8000 Hz).5.Age,BMI,HbA1C,Cr,UA,Hcy,TG,CHOL and LDL-C were the risk factors of hearing loss in T2DM patients with renal injury.