The Correlation Betweenambulatory Blood Pressure Variability And Carotid Intima-media Thickness In Patients With Type 2 Diabetes Mellitus And Hypertension

Objective:To explore the correlation between ambulatory blood pressure variability and carotid artery intima media thickness(CIMT)in type 2 diabetes patients concurrent with hypertension(T2DM+HT).Method:One hundred and forty cases of T2DM+HT who had medical treatments in endocrinology during July 2014 to December 2015 in the Second Hospital of Jing de zheng city were enrolled into the study.The T2DM+HT group was sub-grouped into dippers(n=68,38 males,30 female,aged 35~76 years,mean age 48 ± 13years)and non-dippers(n=72,44 males,28 female,aged 37~75 years,mean age 50 ± 12years),according to the decline in blood pressure at night.Moreover,60 single type 2diabetes(sT2DM)were enrolled as controls(36 males,24 females,aged 36~77 years,mean age 47±14 years).Carotid intima-media thickness was examined by Doppler ultrasound.24 hours non-invasive ABPM was performed using an American TIM device for all patients.Daytime was set from 8:00 AM to 20:00 PM.Nighttime was set from20:00 PM to 08:00 AM.Non-invasive ambulatory BP monitoring device attached to the left arm of the patients.BP readings were obtained every 30 minutes for 24 hours.Patients were advised to record their daily activities.Recordings were adopted if more than 90% of the raw data were valid.Daytime and nighttime parameters is automatically given by the system such as 24 hour mean systolic blood pressure(24hSBP),24 hour mean diastolic blood pressure(24hDBP),mean systolic blood pressur daytime(DSBP),average diastolic blood pressure at daytime(DDBP),daytime mean blood pressure(dMBP),nighttime mean systolic blood pressure(nSBP),nighttime mean diastolic blood pressure(nDBP),pulse pressure at night(nPP)and so on.The nocturnal BP fall(%)was calculated as(daytime SBP-night SBP)/daytime SBP.Nocturnal BP fall was classified as follows: dipper if the nocturnal BP decline was ?10%,non-dipper if it was <10%.The correlation was analyzed betweenparameters and CIMT,and explored between ambulatory blood pressure variability and carotid intima media thickness in patients with type 2 diabetes complicating hypertension.Results:1.In the same age group,CIMT in non-dipper and dipper group were higher than in controls(all P < 0.05).CIMT in non-dipper was higher than in dipper group(P< 0.05).2.The incidence of carotid plaques was 27.9%,41.6%,16.6% in dipper,non-dipper and controls,respectively.The detection rate of carotid plaques in dipper and non-dipper was significantly higher than in controls(P < 0.05).The detection rate of carotid plaques in non-dipper was significantly higher than in dipper(P < 0.05).3.The levels of 24hSBP?24hPP?nSBP?nDBP?nMBP and nPP in dipper and non-dipper were significantly higher than in controls(P < 0.05).The levels of 24 h SBP,24 hPP,nDBP,nMBP and nPP in non-dipper were significatly higher than in dipper.The level of dDBP had no difference in dipper and non-dipper(P > 0.05).4.Age,24 hSBP,24hPP,dPP,nSBP,nMBP,dDBP and nPP were positively correlated with CIMT,and ASBP% was negatively correlated with CIMT by correlation analysis.The successive contribution to artery atherosclerosis in T2DM+HT was WHR,BMI,HbAlC,LDL-C,nPP,nSBP,dPP,24 hSBP,dSBP and TC by multivariate regression analysis.Conclusion:1.CIMT in T2DM+HT patients was higher than that in sT2 DM.2.That the decline in blood pressure at night was not enough,and high blood pressure at night was an easy way to develop atherosclerosis in T2DM+HT.