Study On The Correlation Between Serum Urea Nitrogen And Uric Acid Levels And Pro-BNP In Non-Dialysis Patients With Chronic Kidney Disease Based On The Theory Of "Heart-Kidney Intersection"

1.Background and purpose of the studyAccording to the epidemiological survey of chronic renal disease,the incidence of CKD in our country is about 10.8%,the incidence of CKD in the world is about 13.4%,and the trend is increasing year by year.Studies have put the prevalence of HF in CKD at 17%-21%,while the prevalence of HF in end-stage nephropathy is 44%.According to a consensus of experts published in 2010,clinically defined cardiorenal syndrome（CRS）is a series of acute and chronic impairments in one organ of the heart or kidney that are caused by acute and chronic dysfunction in another.There is no record of"cardiorenal syndrome"in TCM.How-ever,CRS involving lesions of two organs of the heart and kidney can be treated according to the theories of"heart palpitations","heart water","asthma syndrome","edema","stagnation"and"phlegm".Traditional Chinese medicine believes that the pathogenesis of CRS is mostly old age and protracted disease which leads to deficiency of Zang Fu organs.The kidney is the foun-dation of the viscera,and the kidney Yang is the root of all Yang.If one is old and ill,the kidney Qi declines,the kidney Qi declines,the water is transported for excretion and excre-tion,and the water drinks stop gathering.If the water drinks overflow the skin,it is edema;if the water drinks stop the chest and abdomen,it is phlegm drinks;if the water drinks stop the heart and lungs,it is asthma,cough and thrombosis.Water and blood belong to yin and evil,and they can influence each other in pathology.Yang deficiency leads to the loss of water and fluid,resulting in water drink.NT-pro BNP is a common and reliable biomarker for evaluating cardiac function,which can be used as an early predictor of card.Serum urea nitrogen level is a predictor of poor prognosis in patients with heart failure,and the ratio of blood urea nitrogen to creatinine（BUN/SCR）is associated with death risk in patients with heart failure.At present,the correlation between blood urea nitrogen,uric acid and the occurrence and death risk of heart failure is mostly studied in people with heart failure,but less in CKD pa-tients.In order to find the best predictor of early heart failure in CKD patients,this study studied the relationship between blood urea nitrogen,uric acid and NT-Pro BNP.2.Research methodologyIn this study,91 patients with chronic renal disease who were admitted to the Second Af-filiated Hospital of Tianjin University of Traditional Chinese Medicine from September 2018to February 2022 and met the criteria of this study were selected.（1）The e GFR value was calculated according to CKD-EPI_scr-cyformula,and divided into5 groups according to e GFR to explore the relevant influencing factors of Pro-BNP and the value and difference of Pro-BNP in different stages of CKD.（2）The factors related to Pro-BNP were screened by single factor linear regression anal-ysis,and the multifactor linear regression equation was constructed by using the"step-by-step"model to further explore the correlation between blood urea nitrogen,uric acid and Pro-BNP.（3）The correlation of serum uric acid,urea nitrogen and other indicators with Pro-BNP was further explored by grouping early（e GFR≥60 m L/（min 1.73 m²））and late（e GFR<60m L/（min 1.73 m²））CKD.（4）The differences of blood urea nitrogen and uric acid levels among the groups in the middle and late stage of CKD were compared to explore the reasons for the increase of blood uric acid levels.（5）To explore the correlation between blood urea nitrogen and uric acid levels and Pro-BNP in patients with CKD based on"heart and kidney intersection"and microcosmic syndrome differentiation.3 ResultsThe serum levels of BUN and BNP in CKD patients were positively correlated with the decrease of glomerular filtration rate of e GFR,but were not significantly correlated after cor-rection of e GFR,serum uric acid level was positively correlated with serum Pro-BNP,and remained significant after correction of e GFR,etc.4 Conclusion1)Elevated serum uric acid levels were independent predictors of heart failure in patients with CKD.2)The increase of blood urea nitrogen level in CKD patients was mainly related to e GFR.3)The microcosmic syndrome differentiation based on the theory of"intersection of heart and kidney"of TCM shows that serum urea nitrogen of CKD non-dialysis patients is related to the syndrome of deficiency of yang and dampness of spleen and kidney,and blood uric acid is related to the syndrome of water and blood stasis.