Association between Morning Surge and Left Ventricular Hypertrophy in Obese Hypertensive Patients

BACKGROUND

Weight gain can trigger mechanisms that increase blood pressure. Nevertheless, obesity causes structural changes in the myocardium, including increased ventricular mass, atrial dilatation, and diastolic and systolic dysfunction. Additionally, blood pressure variations, like morning surge (MS) in obese hypertensive patients may have clinical relevance in cardiovascular events. Although morning blood pressure surge is a physiological phenomenon, excess MS can be considered an independent risk factor for cardiovascular events.

OBJECTIVE

To evaluate MS values and their association with left ventricular hypertrophy (LVH) and nocturnal dipping (ND) in obese and non-obese hypertensive patients.

METHODS

A cross-sectional study that evaluated BP measurements by ambulatory blood pressure monitoring (ABPM) and the presence of LVH by echocardiography in 203 hypertensive outpatients, divided into two groups: 109 non-obese and 94 obese hypertensives patients. The significance level was set at 0.05 in two-tailed tests.

RESULTS

A MS above 20 mmHg by ABPM was detected in 59.2% of patients in the non-obese group and 40.6% in the obese group. LVH was found in 18.1% and 39.3% of patients in the non-obese and obese groups, respectively, p<0.001. In the "obese group", it was observed that a MS>16 mmHg was associated with LVH, [prevalence ratio: 2.80; 95%CI (1.12-6.98), p=0.03]. For the non-obese group, the cut-off point of MS for this association was >22 mmHg.

CONCLUSION

High MS was positively associated with LVH, with a particular behavior in the hypertensive obese group.

Is there a need to redo many of the diagnoses of hypertension?

CONTEXT AND OBJECTIVE

Most hypertensive subjects undergoing treatment were diagnosed solely through measurements made in the consultation office. The objective of this study was to redo the diagnosis of treated patients after new clinical measurements and ambulatory blood pressure monitoring (ABPM).

DESIGN AND SETTING

Cross-sectional study conducted in an outpatient specialty clinic.

METHODS

Patients with mild-to-moderate hypertension or undergoing anti-hypertensive treatment, without target organ damage or diabetes, were included. After drug withdrawal lasting 2-3 weeks, new blood pressure (BP) measurements were made during two separate visits. ABPM was performed blindly, in relation to clinical measurements. The BP thresholds used for diagnosing hypertension, white-coat hypertension, normotension and masked hypertension were: 140 (systolic) and 90 (diastolic) mmHg for office measurements and 135 (systolic) and 85 (diastolic) mmHg for mean awake ABPM (MAA).

RESULTS

Evaluations were done on 101 subjects (70% women); mean age 51 ± 10 years. The clinical BP was 155 ± 18/97 ± 10 mmHg (first visit) and 150 ± 16/94 ± 11 mmHg (second visit); MAA was 137 ± 13/ 86 ± 10 mmHg. Sixty-four patients (63%) were confirmed as hypertensive, 28 (28%) as white-coat hypertensive, nine (9%) as normotensive and none as masked hypertensive. After ABPM, 37% of the presumed hypertensive patients did not fit into this category.

CONCLUSION

This study showed that hypertension was overdiagnosed among hypertensive subjects undergoing treatment. New diagnostic procedures should be performed after drug withdrawal, with the aid of BP monitoring.

Slow breathing test increases the suspicion of white-coat hypertension in the office

BACKGROUND

It would be useful to have a clinical test that increases the suspicion of white coat hypertension (WCH) during the medical consultation.

OBJECTIVE

To evaluate the Slow Breathing Test (SBT) when differentiating hypertension from WCH.

METHODS

101 hypertensive patients selected at triage had their medication withdrawn for 2-3 weeks. The blood pressure (BP) was measured before and after the SBT at two consultations at the office. The test consisted in breathing for 1 minute at the frequency of one respiratory cycle every 10 seconds. Two diagnostic criteria were compared: 1--decrease in diastolic BP > or = 10% in at least one visit or 2--decrease in BP to normal levels (<140/90 mm Hg) in at least one visit. The ambulatory blood pressure monitoring (ABPM) was performed while blinded to the clinical measurements.

RESULTS

71 women and 30 men, with a mean age of 51+/-10 years, with mean pre and post-test BP of 152+/-17/ 99+/-11 and 140+/-18/ 91+/-11 mm Hg were assessed. Nine patients had normal clinical and ambulatory measurements. Of the 92 patients, 28 (30%) were classified as having WCH; 15 had a positive test for Criterion 1 and 21 for the Criterion 2. Among 64 (70%) hypertensive individuals, 14 tested positive for Criterion 1 and 12 for Criterion 2. Sensitivity and specificity (95% CI): 0.54 (0.36-0.71) and 0.78 (0.67-0.87) for Criterion 1; 0.75 (0.57-0.87) and 0.81 (0.70-0.89) for Criterion 2.

CONCLUSION

The SBT showed an increase in the clinical suspicion of WCH in two visits when using the BP normalization criterion. This finding suggests that the test can help in the optimization of ABPM requests for suspected cases.