A Study Of Intima Thickness And Media Thickness Of Carotid And Peripheral Arteries In Diabetic Patients By High-resolution Ultrasound

BackgroundWith the improvement of residents’ living conditions and the change of diet,the prevalence of diabetes mellitus(DM)increased significantly.According to the data from the International Diabetes Federation(IDF),there are more than 140 million Chinese with diabetes in 2021,mainly type 2 diabetes(T2MD).The prevalence rate of men is higher than that of women,and that of urban areas is higher than that of rural areas.Long-term chronic hyperglycemia will lead to heart,blood vessels,kidneys,eyes,nerves and other damage and dysfunction.Diabetes mellitus complicated with cardiovascular and cerebrovascular diseases(including cerebral infarction,coronary heart disease,etc.)is more likely to lead to poor prognosis,which is the main factor of death in patients with diabetes,and greatly affects their quality of life,so it is very important to detect and treat diabetes and its cardiovascular and cerebrovascular diseases as soon as possible.Diabetic cardio-cerebrovascular disease is secondary to atherosclerosis(AS).Hyperglycemia and insulin resistance of vascular cells accelerate AS.Carotid artery is a common site of AS.At present,carotid intima-media thickness(CIMT)is often measured by ultrasound to reflect the degree of carotid atherosclerosis,which has been used as a marker of subclinical arteriosclerosis.Non-invasive ultrasound imaging technology has become the most commonly used method in clinical vascular imaging examination because of its convenience and economy.The ultrasonic probe emits and receives ultrasonic wave in the process of ultrasonic testing,and the emission frequency affects the ultrasonic resolution and penetration.The higher the frequency,the higher the resolution,but the faster the attenuation,the shallower the depth of exploration.CIMT includes carotid intima thickness(CIT)and carotid artery media thickness(CMT).The pathological changes of AS mainly occur in the intima layer.On the contrary,other factors such as hypertension mainly affect the media thickness.Therefore,the composite index of intima-media thickness(IMT)has some limitations in the reflection of AS lesions.IMT thickening may have the influence of hypertension and other factors on media thickness.Measuring arterial intima thickness alone to reflect AS lesions may be more valuable than measuring intima-media thickness.At present,the clinical exploration of carotid and peripheral arteries mainly uses 5-10MHz linear probe,the resolution is 200-400 μm,the resolution is low,can not clearly show the fine structure of the arterial wall,it is difficult to measure the intima or media alone.High-frequency ultrasound(20-100MHz)appeared in the 1990s,its imaging precision of superficial organs is much higher than that of ordinary resolution ultrasound,so it has been widely used in ophthalmology.Some studies have found that high-frequency ultrasound has higher image quality and accuracy for the superficial vessels within the subcutaneous 20mm.In this study,a new type of 24-MHz high-resolution ultrasound probe is selected,with a resolution of 60 μm and a measurement accuracy of 0.01mm,which can clearly distinguish the intima and media of the artery.It is expected to be more sensitive and accurate to reflect AS lesions,and can meet the needs of detecting carotid artery,radial artery and dorsalis pedis artery at the same time.Xu et al confirmed that there was a strong correlation between intimal thickness measured on 24MHz ultrasound images and vascular pathology(r=0.947,P<0.001).Moreover,the variability of arterial intimal thickness measured by 24-MHz high-resolution ultrasound was small and the repeatability was high.Some studies have confirmed that arterial intimal thickness has diagnostic and differential diagnostic value in patients with coronary heart disease and stroke.At present,its diagnostic and predictive value in cardiovascular and cerebrovascular diseases in patients with diabetes mellitus has not been reported.Peripheral arteries are also involved in diabetic patients,and their risk of developing peripheral arterial disease is 2-4 times higher than that in non-diabetic patients.Diabetic foot,one of the most common complications in patients with poorly controlled blood sugar,is usually accompanied by peripheral artery disease.Objectives1.The intima thickness and media thickness of carotid artery,radial artery and dorsalis pedis artery were measured and compared between diabetic patients and non-diabetic patients,diabetic patients with and without cardio-cerebrovascular diseases,diabetic patients with and without hypertension by 24-MHz high-score ultrasound.2.To analyze the influencing factors of intima thickness and media thickness of carotid artery,radial artery and dorsalis pedis artery in patients with diabetes mellitus.MethodsThe study recruited a total of 221 diabetic patients from the Department of Endocrinology at both the Second Hospital of Shandong University and Qilu Hospital of Shandong University.In addition,100 healthy subjects matched with sex and age in the health examination center in the same period were selected as the control group.The general data of age,sex,height,weight,smoking history,drinking history,systolic blood pressure(SBP),diastolic blood pressure(DBP),coronary heart disease,cerebral infarction,hypertension,antihypertensive drug use,statins use and discharge diagnosis were collected,and the body mass index was calculated according to height and body weight.At the same time,triglyceride(TG),total cholesterol(TC),high density lipoprotein cholesterol(HDLC),low density lipoprotein cholesterol(LDL-C),apolipoprotein 1(ApoA-1),apolipoprotein B(ApoB),small and dense low density lipoprotein(sdLDL),nonestesterified fatty acid(NEFA),cystatin C(Cys_C),lipoprotein a(LPa),homocysteine(HCY),creatinine(Cr),alanine aminotransferase(ALT),fasting glucose(GLU)and so on were collected.Using Aplioi900(Canon-Toshiba Ultrasound,Tochigi-ken,Japan)color Doppler ultrasound diagnostic instrument,connected with 24-MHz probe(i24Lx8),all subjects lay flat for 5 minutes,keeping supine position connected with ECG monitoring.Carotid artery images were collected at the posterior wall of 1.5cm,2cm and 2.5cm at the distance bifurcation of bilateral common carotid arteries,and radial artery images were collected at 1-2cm above the styloid process of bilateral radius.The images of dorsalis pedis artery were collected by 2-3cm below the line of bilateral internal and external malleolus,and the intima thickness and media thickness of each artery were measured at the peak of R wave of ECG,that is,end-diastolic phase.Each part was measured three times and its average value was taken as the final value of the part.Statistical analysis and mapping were carried out by using SPSS26.0(SPSSInc.,Chicago,IL,USA)and GraphPadPrism9.0.0(GraphPad Software,SanDiego,California,USA)software.The mean and standard deviation are used to express continuous variable data,while frequency(percentage)is used to express classified data.Normality test is conducted using the K-S test.Independent sample T-test is used to compare measurement data between two groups that conform to normal distribution,while one-way ANOVA is used to compare data among multiple groups that conform to normal distribution.Nonparametric tests are used to compare measurement data between two groups that do not conform to normal distribution,and the KW test is used to compare data between multiple groups that do not conform to normal distribution.Chi-square test is used to compare classified variable data between groups,while Spearman correlation test is used for correlation analysis.Multivariate linear regression is used to explore influencing factors,with P<0.05 indicating statistical significance.Results1.Compared with the control group(n=100),the CIT,CMT,CIMT,RIT,RMT,RIMT and PIT of the diabetic group(n=221)were thicker,but there was no significant difference in PMT and PIMT between the two groups.2.Compared with control group(n=100),CIT,CIMT,RIT,RIMT,PIT in diabetic group without cardio-cerebrovascular disease(n=87)were thickened,CIT,CMT,CIMT,RIT,RMT,RIMT,PIT,PMT,PIMT in diabetic group with cardio-cerebrovascular disease(n=134)were thicker.CIT,CMT,CIMT,RMT,RIMT,PMT,PIMT in diabetic group with cardiocerebrovascular disease were thicker than those in diabetic group without cardiocerebrovascular disease.3.Compared with the control group(n=100),the CIT,CIMT,RIT,RIMT and PIT of the diabetic group without hypertension(n=87)were thickened,the CIT,CMT,CIMT,RIT,RMT,RIMT,PIT,PMT and PIMT of the diabetic group with hypertension were thicker,and the CMT,CIMT,RMT,RIMT,PIT,PMT and PIMT of the diabetic group with hypertension(n=134)were thicker than those of the group without hypertension.4.The main influencing factors of CIT were age,SBP,DBP and NEFA;The main influencing factors of RIT were age,HDL-C,NEFA,HCY,Cr and Cys_C;The main influencing factors of PIT were age,history of hypertension and GLU.5.The main influencing factors of CMT were age,SBP and hypertension history,while the main influencing factors of RMT were age,smoking history and SBP;PMT were age,sex,SBP and NEFA.Conclusions1.The intima thickness,CMT and RMT of carotid artery,radial artery and dorsalis pedis artery of diabetic patients were thicker than those of healthy people;the intimal thickness of carotid artery of diabetic patients with cardio-cerebrovascular disease was thicker than that of diabetic patients without cardio-cerebrovascular disease;the CIT,RIT and PIT of diabetic patients without hypertension were thicker than those of healthy people,and the CMT and RMT of diabetic patients with hypertension were thicker than those of patients without hypertension.2.CIT,RIT and PIT were related to age,hypertension,blood glucose,blood lipid and Cys_C,while CMT,RMT and PMT were related to age and history of hypertension.