Nocturnal reduction of blood pressure and the antihypertensive response to a diuretic or angiotensin converting enzyme inhibitor in obese hypertensive patients

Abstract

During a 12-week, multicenter study to evaluate the efficacy and safety of lisinopril and hydrochlorothiazide (HCTZ) for the treatment of obesity-related hypertension, ambulatory blood pressure (ABP) monitoring was performed both at baseline and at study completion in 124 patients. Patients were randomized to three groups: placebo, lisinopril (10, 20, or 40 mg/day), or HCTZ (12.5, 25, or 50 mg/day). All groups were matched with regard to sex, race, age, body mass index, and waist/hip ratio. The primary analysis of ABP data revealed that both lisinopril and HCTZ effectively lowered mean 24-h systolic (SBP) and diastolic (DBP) blood pressure compared with placebo, (mean change from baseline SBP/DBP: -12.0/-8.2, -10.6/-5.5, and -0.3/-0.5 mm Hg, respectively); however, lisinopril lowered DBP better than HCTZ (P < .05). Secondary analyses of groups revealed that men responded better to lisinopril than HCTZ (-11.9/-7.3 v -6.6/-3.5 mm Hg, respectively), whereas women responded well to both drugs. White patients responded better to lisinopril than HCTZ, whereas black patients showed a significant response to HCTZ only. Response to treatment was also influenced by patient classification of 24-h blood pressure profiles, ie, "dipper" or "nondipper." Overall, the majority of obese hypertensives were nondippers. Nondippers (n = 82) responded well to both drugs (-10.4/-6.9 v -12.5/-5.7 mm Hg, P < .05 v placebo), whereas dippers (n = 42) responded to lisinopril (-11.7/ -9.4 mm Hg, P < .05 v placebo and HCTZ), but not HCTZ (-5.6/-4.1 mm Hg, P = NS v placebo). Results of 24-h ABP data show that both lisinopril and HCTZ are effective therapies for obesity-related hypertension and that response to treatment is influenced by sex, race, and dipper/nondipper status.

Diuretics Shift Circadian Rhythm of Blood Pressure From Nondipper to Dipper in Essential Hypertension

“…20 These authors also showed that hydrochlorothiazide effectively lowered 24-hour BP in nondippers and blacks, whose elevated salt sensitivity has been previously described. 3,4,9,10,12 In the present study, similar to the previous report, 20 the response to hydrochlorothiazide therapy in nondippers was greater than that in dippers. These findings, together with the present study, indicate that diuretics lower nighttime BP, especially in salt-sensitive hypertensives, and shift the circadian rhythm of BP in these patients from nondipper to dipper.…”

Overlap Between Whites and Blacks in Response to Antihypertensive Drugs

“…Most previous studies that reported race-specific baseline blood pressures (Table 1) had a 2-to 4-mm Hg higher baseline diastolic blood pressure among blacks compared with whites. [11][12][13][14][15][16] Thus, these studies may overestimate the difference in the proportion of whites and blacks achieving a target blood pressure after administration of a specific antihypertensive drug. Many other studies did not report baseline blood pressure separately for whites and blacks (Table 1), thereby making if difficult to interpret their results regarding racial differences in achieving a treatment goal.…”

Changes of Nocturnal Blood Pressure Dipping Status in Hypertensives by Nighttime Dosing of α-Adrenergic Blocker, Doxazosin

“…If the second evaluation is made after administering a drug, the apparent effect of the drug will be to produce a greater fall of nocturnal BP in the nondippers than in the dippers (as we observed). The best way to exclude this effect is to administer placebo pills to a control group, 23,24 but this may be difficult to perform in the clinical practice setting. Recently, after the recognition of the potential clinical significance of differences in dipping patterns, there have been several studies of the effects of antihypertensive drugs in hypertensive subjects who differ in their nocturnal BP dipping status.…”