Comparation Analysis For Diagnostic Assessment For Diabetic Cardiovascular Autonomic Neuropathy

Objective:The prevalence of Diabetes mellitus is growing rapidly, diabetic neuropathies are the most common chronic complication of both type 1 and type 2 diabetes. Autonomic neuropathy affects about 60% of the DM patients. Diabetic cardiovascular autonomic neuropathy(DCAN) is defined as the impairment of the autonomic(sympathetic and parasympathetic) function of the cardiovascular system in the setting of diabetes after exclusion of other causes, lead to arrhythmia and vasomotor dysfunction. Symptoms include increased and fixed heart rate, angioregulatory dysfunction such as postural hypotension, painless myocardial infarction and sudden death due to cardiac arrest.Several diagnostic approaches are available and have been used to diagnose DCAN in practice or research, including study of heart rate variability(HRV) using the ratio of the RR intervals of the ECG, cardiovascular autonomic reflex tests(CARTs), imaging techniques, baroreflex sensitivity and muscle sympathetic nerve activity test. Among them, HRV assessment is recommended as the gold standard for clinical testing, and CARTs are also widely used for its safety and reproducibility. The objective is to compare and analysis the value of two cardiovascular autonomic fuction examinational methods, to find out the sensitivity of CARTs and the variability between these two methods in diagnosing DCAN.Methods:1 Study ParticipantsIn accordance with WHO diagnostic criteria for diabetes mellitus in 1999: FBG≥7mmol/L and/or 2h PG≥11.1mmol/L(n=80 37 to 78 yr), with a 0-20 years duration;2 Exclusion ParticipantsExclusion of coronary artery disease, heart failure, infection, fever, acute complication and those who take pills that affects HRV.3 methodsDetect cardiovascular autonomic function of the diabetic patients by 3 out of 5 CARTs(Ewing’s test) and heart rate variability test. The CARTs test include standing blood pressure test, heart rate response to standing(30:15 ratio) and heart rate response to breathing(E:I ratio). The clinical characteristics of the patients were recorded too, including Hb A1 c, blood fat, and general information.4 Statistical analysisApplication SPSS13.0 statistical software. Enumeration data were analyzed by variance test, relation between variables was analyzed with linear regression. All data were represented by Mean±SEM.Results:1 The diagnose rate of diabetic cardiovascular autonomic neuropathy by Ewing’s test(73.8%) is slightly higher than that of HRV’s(70%), but has no statistical significance(P>0.05).2 Ewing’s test and HRV test have correlated relation.3 Devide the patients into two groups(DCAN+ and DCAN-) according to the HRV test result. Results shows that age, Hb A1 c and blood fat have no statistical significance(P>0.05), and the duration of diabetes has statistical significance.Conclusions:1 There is no statistical difference between the CARTs and HRV’s test in diagnosing cardiovascular autonomic disease. CARTs DCAN be used to screen DCAN clinically for it has a satisfying correlation with the HRV’s test, easy to proceed, and costs much lower than other tests.2 Duration is a main factor that affects the cardiovascular autonomic neuropathy.