The Cumulative Blood Pressure Load And Target Organ Damage In Patients With Essential Hypertension

Objective To analyze and improve the calculation method of the area under the blood pressure curve in 24-hour ambulatory blood pressure monitoring,to investigate the relationship between the area under the blood pressure curve,mean blood pressure,blood pressure variability,and to explore the predictive value of the area under the blood pressure curve on target organ damage in patients with essential hypertension.Methods This study was based on a retrospective cohort study.We enrolled in 634 patients with essential hypertension who were hospitalized in the cardiology department of Daping Hospital from January 2005 to December 2018 with a course of more than one year were included.TOD was defined as the presence of left ventricular hypertrophy and carotid plaque.All participates was underwent 24-hour ABPM,cardiac ultrasound,and carotid artery ultrasound.The cumulative blood pressure load was obtained by analyzing the ABPM data and improving the calculation method of the area under the blood pressure curve.Logistic regression analysis was used to evaluate the relationship between cumulative blood pressure load and Target Organ Damage(TOD),and receiver operator characteristic(ROC)curve was used to analyze the predictive value of cumulative blood pressure load on TOD.Results This study included 634 participants and 298(47.0%)men,and their ages were between 38 years and 93 years(mean ± SD age: 64.5 ± 12.7 years).The mean duration of hypertension was 8.9 ± 8.4 years.Of the 634 participants,168 patients(26.5%)had a history of smoking,240(33.8%)had coronary heart disease,56(8.8%)had type 2 diabetes,and 48(7.6%)had cerebral infarctions.Three hundred and ninety-two patients(61.8%)had left ventricular hypertrophy(LVH)and 316 patients(49.8%)had carotid artery plaques.11.8%of patients were taking angiotensin converting enzyme inhibitor,24.3% of patients were taking angiotensin Ⅱ receptor antagonist,12.3% of patients were takingβ-Blockers,44.2%of patients were taking calcium channel blocker,and 7.6% of patients were taking Diuretics.The mean SBP and %SBPL were slightly higher in the patients with LVH than in those without LVH group(P < 0.007,P < 0.007).Except for the diurnal the cumulative systolic pressure load(c SBPL),all the c BPL indices were significantly higher among the patients who had detectable carotid artery plaques than those who did not have carotid artery plaques(all P< 0.05).Spearman’s correlation coefficients were determined to assess the associations between the c BPL and conventional ambulatory blood pressure parameters,namely,the mean blood pressure,blood pressure load,and blood pressure variability.This analysis showed strong correlation between the cumulative blood pressure load and mean blood pressure and blood pressure load.The c BPL weakly correlated with blood pressure variability.Logistic regression analyses showed that the nocturnal c SBPL,24-h c SBPL,nocturnal cumulative pulse pressure load(c PPL),and 24-c PPL and the conventional ABPM parameter systolic pressure,were associated with TOD.After adjusting age,sex,body mass index,smoking,fasting plasma glucose,total cholesterol,low-density lipoprotein cholesterol,triglycerides,24-hour systolic blood pressure,hypertension duration,antihypertensive,only the nocturnal c SBPL was independently associated with LVH [(Odds Ratio,OR)= 1.002,95% confidence interval(CI): 1.001-1.004,P <0.000],the nocturnal c SBPL(OR = 1.003,95% CI:1.002-1.005,P <0.000)and nocturnal c PPL(OR = 1.002,95% CI: 1.001-1.004,P = 0.004)were associated with the presence of carotid artery plaques.The ROC curve analysis showed that the nocturnal cumulative systolic blood pressure and cumulative pulse pressure load,relative to mean blood pressure,were superior in predicting hypertensive target organ damage.Conclusion The cumulative blood pressure load is a better indicator of blood pressure consequences,and the nocturnal cumulative systolic blood pressure and cumulative pulse pressure loads could predict target organ damage.