Relationship Between Serum Resistin And Ankle Brachial Index In Essential Hypertensive Patients

Objective: Atherosclerosis (AS) is a systemic and continual disease, which not only involves coronary artery and cerebral artery, but also implicates multiple arterial vascular beds, including the peripheral artery. Coronary Heart Disease (Coronary Disease), Cerebral Arterial Thrombosis, and Peripheral Artery Disease (PAD) are important forms of AS. Among them, PAD is not only an important manifestation of systemic AS, but also closely related to cerebrovascular and cardiovascular diseases and even deaths. Ankle brachial index (ABI), denoting the ratio of SABP of lower limbs and ankles to that of upper arms and brachial, is a simple index in diagnosing PAD; in recent years, ABI obtains increasing attention as an important measurement means of AS.Resistin is a new type of adipocytokines and was named for its restrain of insulin-mediated glucose and its resistance to insulin. As the development of general research on resistin, people have realized that there is a difference between the gene expressions, molecular structures, and functions between human resistin and animal resistin. In animal's body, resistin is specifically expressed by adipocytes, and most studies are in favor of the conclusion that resistin harms organism's sugar tolerance and influences organism's sensibility to insulin. While in human body, resistin's restrain to insulin and obesity is mainly related to inflammations and AS. Resistin can participate in the pathophysiologic process of AS by intensifying the inflammation. The endothelial dysfunction and injury may result in AS, with the endothelial adhesiveness for mononuclear cell expressed by upregulation-mediated Mel-CAM as its significant mechanism. Many clinical tests prove that the level of resistin is related to epidemic, early pathogenesis, seriousness, and prognosis of coronary disease.Nevertheless, the research on the relationship of resistin and peripheral artery atherosclerosis is still limited. This paper studies the observation of the abnormal rate of ABI in patients with hypertension; and the altered resistin in patients with hypertension as well as its relevance of ABI.Methods: 140 primary hypertension patients that attended the cardiology clinic of the Second Affiliated Hospital of Hebei Medical University from March, 2009 to October, 2009, were selected (except those with coronary disease, stroke, or intermittent claudication). All of them met the diagnostic criterion in"Chinese Hypertension Guideline"of 2005. The patients'general conditions (gender, age, height, weight, hip circumference) were recorded, and information about their history of diabetes, hyperlipaemia, and smoking was collected to calculate the weight index BMI. We also used OMRON full-automatic AS detector (BP203RPE-II) to measure patients'ABI on both sides of the body and concluded the lower number into statistics. The patients have their blood sample taken after 10 hours'limosis, and the samples were used to determine the index including serum resistin, fasting blood-glucose (FBG), total cholesterol (TC), triglyceride (TG), lower density lipoprotein cholesterol (LDL-C), etc.We had a statistical analysis with statistical software SPSS 13.0. Quantitative data were presented in the forms of"mean±standard deviation", while enumeration data were presented in frequency or percentage. Statistical significance is proved if P<0.05, with measurement data and enumeration data examined by t-distribution. On relevant numerical values, linear analysis, analysis of variance, and analysis of multivariable linear regression were conducted.Results: Two of the 140 patients had ABI smaller than 0.9 and the prevalence rate of PAD is 1.4% in EH patients.The patients were divided into two groups according to whether they fit the criteria of diabetes besides that of hypertension. A tau-distribution analysis showed that ABI of patients who have both hypertension and diabetes(1.00± 0.08) was higher than that of patients with hypertension only(1.14±0.05), while the level of serum resistin indicated an opposite trend. Moreover, P<0.01 proved the existence of statistical difference. The serum resistin respectively was 6.81±2.54 and 5.26±1.86.According to the grading standards in"Chinese Hypertension Guideline"of 2005, hypertension patients are classified to three groups: the first-level hypertension, the second-level hypertension, and the third-level hypertension. ABI of the three groups was 1.13±0.08, 1.11±0.07, 1.10±0.07 respectively.The serum resistin respectively was 5.65±2.22, 5.36±2.07, 5.67±1.51. A variance analysis of ABI and serum resistin among the three groups led to P>0.05, indicating no statistical difference. According to WGOC's suggestion on the classification of adults'overweight and obesity, we divided the patients to three groups by points of BMI=24kg/ m2 and BMI=28kg/ m2. ABI of the three groups was 1.13±0.05, 1.12±0.08, 1.11±0.09 respectively, The serum resistin respectively was 4.92±1.75, 5.71±2.24, 5.73±2.06. A One-way analysis of variance of the three groups'ABI and serum resistin indicated no statistical difference with the result P>0.05.With serum resistin as the independent variable and ABI as the dependent one, a analysis of linear correlation was conducted, yielding a correlation coefficient (r) of -0.387, P<0.01, indicating a negative linear correlation between ABI and serum.Next we conducted the analysis of multivariable linear regression of ABI and other factors in the patients with hypertension only. ABI was chosen as the independent variable with other factors as the dependent variables to conduct the analysis of multivariable linear regression. Independent variables included age, FBG, TG, LDL-C, serum resistin and SBP, NBP all of which were metric variables. Dichotomous variable included gender and disease history. The male patients or patients with hyperlipaemia or smoking history was assigned with 1, while the female patients or patients without such history were assigned with 0. Finally, two influence factors entered the regression equation, they were LDL-C, serum resistin. The standardized regression coefficients of them was -0.337(P=0.000), -0.233(P=0.008) respectively.Conclusion: In this project, two of the patients had ABI smaller than 0.9 and prevalence rate of PAD is 1.4%. Patients with both diabetes and hypertension had an evidently lower ABI and a higher level of serum resistin than those with hypertension only. Diabetes has influence on both ABI and serum resistin.With the raise of blood pressure, ABI tends to decline. But such difference in serum resistin level has no statistical significance; as the increase of body weight, ABI of obese people tends to decline, while serum resistin tends to increase, but still, no statistical significance existed.A negative linear correlation between serum resistin and ABI was proved. Eliminating the influence of diabetes, an analysis of multivariable linear regression of ABI showed a relevance of serum resistin and ABI, indicating that an increased serum resistin could be one of the major triggers to the occurrence of peripheral arterial atherosclerosis in patients with hypertension.