The Relationship Between Angiotensin Ⅱ Receptor Antagonist And Circadian Rhythm Of Blood Pressure In Chronic Kidney Disease

Background and purposeThere is close relationship between high blood pressure and kidney. Kidney is not only the cause that can lead to high blood pressure ,but also the target organ that the hypertension damage. American Kidney Foundation Kidney Early Evaluation Plan for the kidney disease with hypertension in the health screening showed that the prevalence rate of hypertension in chronic kidney disease was 86.2%, but control rate is very low, only 13.2%.Mean of blood pressure in patients with CKD is high, circadian rhythm was lost and the phenomenon of the morning peak is obvious.The circadian rhythm of blood pressure showed systolic and diastolic blood pressure of daytime is higher , but systolic and diastolic blood pressure of nighttime decreased lower. The model of blood pressure was a typical non-dipper blood pressure . With the decline of renal function, the incidence of non-dipper blood pressure in CKD patients gradually increased, even in regular dialysis patients, the occurrence rate of non-dipper blood pressure is still 50% to 80%. This study, through the change of circadian rhythm of blood pressure after CKD patients taking angiotensinⅡreceptor antagonists, discuss the relationship between angiotensinⅡreceptor antagonists and circadian rhythm of blood pressure.Research MethodsWe choose 60 patients including 30 CKD stage 2 patients and 30 CKD stage 3 patients with hypertension, which inpatient or outpatient at the Second Affiliated Hospital of Chongqing Medical University from January 2010 to January 2011.The 60 patients were randomly divided into 3 groups, named CCB,CCB+ACEI and CCB+ARB . CCB group was provided Norvasc or Adalat; CCB+ACEI group was provided Norvasc or Adalat plus Lotensin or Acertil; CCB+ARB group was provided Norvasc or Adalat plus Telmisartan or Anbo Wei.All patients took the 24-h ambulatory blood pressure measurement, and collected day (am06 :00-pm21: 00) and night (pm21 :00-am06: 00) urine before taking the experimental drug. The patients should disable the original antihypertensive drug instead of experimental drugs in 4 weeks before the experiment. Such as, CCB group was provided with Norvasc or Adalat, CCB+ACEI group was provided Norvasc or Adalat plus Lotensin or Acertil,CCB+ARB group was provided Norvasc or Adalat plus Telmisartan or Anbo Wei . Each drug was started with low dose, and gradually increased. Everyday the patient should examine the blood pressure at 8:00 am. When the systolic blood pressure was less than 140mmHg and diastolic blood pressure was less than 90mmHg in three days, the patient can maintain the same dosage. During the experiment, the patient should monitor the serum creatinine and potassium every week. If the serum creatinine increase 1mg/dl in 3 weeks before the experiment, and continue increasing , ACEI or ARB drugs should not be used. After 8 weeks, the patients should take the 24-h ambulatory blood pressure measurement, and collection day (am06 :00-pm21: 00) and night (pm21 :00-am06: 00) urine again. During the experimental period , all patients should limit sodium (about 8g sodium everyday), try to get up at 6:00-7:00 am, and sleep at 21:00-22:00pm.The patient was allowed the basic daily activities. During the experiment, the patient was not allowed to add a new drug or change the dose and type of original drug.ResultsCompared with the experimental results before the study, 24h-S BP,d-S BP,d- DBP,n-SBP of CCB group,CCB + ACEI group and CCB + ARB group were significantly reduced (P <0.05); Compared with the CCB group, the decreased of 24h- SBP,d-S BP,n-DBP in CCB + ACEI group and CCB + ARB group after the experiment were significantly increased (P<0.05); The decrease of 24h- SBP,24h-DBP,d-DBP及n-DBP between CCB + ACEI group and CCB + ARB group after the experiment has no significant difference (P> 0.05); Compared with CCB + ACEI group,the decrease of d-SBP in CCB + ARB group after the experiment significantly reduced (P <0.05),while the n-SBP significantly increased (P <0.05).Compared with CKD stage 2 before the experiment,the rate of non-dipper in CKD stage 3 was significantly increased (P<0.05);Compared with CCB group and CCB + ACEI group, CCB + ARB group improve the circadian rhythm of blood pressure more obvious (P <0.05). Before the experiment, 24h-UnaV, d-UnaV, n-UnaV of CCB group,CCB + ACEI group and CCB + ARB group have no significant difference between each other (P> 0.05);After the experiment ,24h-UnaV of CCB group, CCB + ACEI group and CCB + ARB group have no significant difference between each other (P> 0.05); After the experiment ,d-UnaV, n-UnaV of CCB group and CCB + ACEI group have no significant difference between each other (P> 0.05); After the experiment ,compared with CCB group and CCB + ACEI group,d-UnaV of CCB + ARB group significantly increased (P <0.05), while the n-UnaV significantly reduced (P <0.05). Before the experiment, night / day ratio of MAP in CCB group,CCB + ACEI group and CCB + ARB group have no significant relationship with the night / day UnaV(y=0.107x+0.808, R2=0.136,P=0.110;y=0.053x+0.854,R2=0.050,P=0.346;y=0.084x+0.829, R2=0.108,P=0.157); After the experiment, night / day ratio of MAP in CCB group and CCB + ACEI group have no significant relationship with night / day UnaV(y=0.057x+0.849,R2=0.048,P=0.351;y=0.088x+0.825,R2=0.126, P=0.124),while the night / day ratio of MAP in CCB + ARB group has positive relationship with the night / day UnaV (y=0.266x+0.826,R2=0.492, P=0.001).Conclusion1.With the decline of renal function, the incidence of non-dipper blood pressure in CKD patients gradually increased.2.Patients given combination therapy have a greater reduction in blood pressure than the monotherapy group.3.AngiotensinⅡreceptor antagonists can increase daytime urinary sodium excretion rate and reduce nighttime urinary sodium excretion rate in patients with CKD, then convert the blood pressure rhythm from non-dipper to dipper.