ABSTRACT
Leptin and aldosterone have been associated with the pathophysiological mechanisms of hypertension. However, despite studies showing the association of leptin with intima-media thickness, arterial distensibility and sympathetic nerve activation, the relationship between leptin and blood pressure (BP) in resistant hypertension (RHTN) is unknown. We aimed to assess the correlation of plasma leptin and aldosterone levels with BP in uncontrolled controlled RHTN (UCRHTN) and CRHTN patients. Plasma leptin and aldosterone levels, office BP, ambulatory BP monitoring and heart rate were measured in 41 UCRHTN, 39 CRHTN and 31 well-controlled HTN patients. No differences were observed between the three groups regarding gender, body mass index and age. The UCRHTN group had increased leptin when compared with CRHTN and well-controlled HTN patients (38.2±21.4, 19.6±8.7 and 20.94±13.9 ng ml(-1), respectively; P<0.05). Aldosterone levels values were also statistically different when comparing RHTN, CRHTN and well-controlled HTN patients (9.6±3.8, 8.1±5.0 and 8.0±4.7 ng dl(-1), respectively; P<0.05). As expected, UCRHTN patients had higher heart rate values compared with CRHTN and well-controlled HTN patients (86.2±7.2, 83.5±6.7 and 83.4±8.5, respectively; P<0.05). Plasma leptin positively correlated with systolic (SBP) and diastolic BP (DBP), and aldosterone (r=0.43, 0.35 and 0.47, respectively; all P<0.05) in UCRHTN, but neither in the CRHTN nor in the HTN group. Simple linear regression showed that SBP, DBP and aldosterone may be predicted by leptin (r(2)=0.16, 0.15 and 0.19, respectively; all P<0.05) only in the UCRHTN subgroup. In conclusion, UCRHTN patients have higher circulating leptin levels associated with increased plasma aldosterone and BP levels when compared with CRHTN and HTN subjects.
Subject(s)
Antihypertensive Agents/therapeutic use , Blood Pressure/drug effects , Drug Resistance , Hypertension/drug therapy , Leptin/blood , Aged , Aldosterone/blood , Biomarkers/blood , Blood Pressure Monitoring, Ambulatory , Female , Heart Rate , Humans , Hypertension/blood , Hypertension/diagnosis , Hypertension/physiopathology , Linear Models , Male , Middle Aged , Predictive Value of Tests , Risk Factors , Treatment Failure , Up-RegulationABSTRACT
Resistant hypertension (RHTN) includes both patients whose blood pressure (BP) is uncontrolled on three or more medications (uncontrolled RHTN (UCRH)) and patients whose BP is controlled with use of four or more drugs (controlled RHTN (CRH)). It is unknown whether endothelial function and nocturnal drop demonstrate a similar pattern in patients with CRH and UCRH. We examined circadian BP patterns and vascular function in these patients. In all, 40 CRH and 26 UCRH patients, and 25 normotensives underwent biochemical testing, ambulatory BP monitoring, determination of brachial artery responses to endothelial-dependent (flow-mediated; dilation (FMD)) and independent (nitroglycerin mediated) stimuli. The nighttime drop in systolic BP (SBP) and diastolic BP (DBP) was less pronounced in UCRH than in CRH (SBP, 1.9±1.6 versus 4.9±1.7%; DBP, 7.5±1.8 versus 10.9±1.8%, UCRH and CRH, respectively; P<0.05). FMD was greater in control group compared with RHTN patients. Patients with UCRH had significantly impaired FMD compared with CRH (5.9±2.3% versus 7.1±5.1%; P<0.0001). Therefore, UCRH patients have less nocturnal dipping and a more impaired endothelial response compared with CRH patients. These findings suggest that important differences among patients with RHTN may allow identify subgroups with increased cardiovascular risk.
Subject(s)
Blood Pressure , Brachial Artery/physiopathology , Circadian Rhythm , Endothelium, Vascular/physiopathology , Hypertension/physiopathology , Vasodilation , Adult , Analysis of Variance , Antihypertensive Agents/administration & dosage , Blood Pressure/drug effects , Blood Pressure Monitoring, Ambulatory , Brachial Artery/diagnostic imaging , Brachial Artery/drug effects , Brazil , Cardiovascular Diseases/etiology , Cardiovascular Diseases/physiopathology , Drug Resistance , Drug Therapy, Combination , Endothelium, Vascular/diagnostic imaging , Endothelium, Vascular/drug effects , Female , Humans , Hypertension/blood , Hypertension/complications , Hypertension/diagnosis , Hypertension/drug therapy , Linear Models , Male , Middle Aged , Nitroglycerin/administration & dosage , Risk Assessment , Risk Factors , Treatment Failure , Ultrasonography , Vasodilation/drug effects , Vasodilator Agents/administration & dosageABSTRACT
Resistant hypertension (RHTN) includes patients whose blood pressure (BP) is controlled with the use of four or more antihypertensive medications, and is referred to as 'controlled resistant hypertension' (CRH). While specifically comparing patients with CRH and uncontrolled resistant hypertension (UCRH), we hoped to identify distinguishing characteristics that would provide insight into factors contributing to resistance to antihypertensive therapies. RHTN patients were identified as controlled (CRH, n=43) or uncontrolled (UCRH, n=47). No statistical differences were observed between the CRH and UCRH subgroups with respect to age and gender. The body mass index, aldosterone-renin ratio and pulse wave velocity (PWV) were significantly higher in UCRH patients. Although both subgroups showed increased cardiac mass, left ventricular mass index was significantly higher in UCRH compared with CRH patients. Multivariate linear regression analysis indicated that PWV was significantly dependent on age in both UCRH and CRH patients; however, the influence of ageing was more pronounced in the former subgroup. Older age, greater vascular stiffness, higher aldosterone levels and greater left ventricular hypertrophy were significantly associated with lack of BP control in patients with RHTN. These findings suggest important possibilities in terms of preventing and better treating RHTN.
