Alain Carré

Electronic pill-boxes in the evaluation of antihypertensive treatment compliance: comparison of once daily versus twice daily regimen.

The objective was to compare the compliance of hypertensive patients treated with captopril twice daily or trandolapril once daily. After a 2-week placebo period, hypertensive patients (diastolic BP 95-115 mm Hg) were randomly allocated to trandolapril 2 mg once daily or to captopril 25 mg twice daily for 6 months. Trandolapril and captopril were packed in electronic pill-boxes equipped with a microprocessor that recorded date and time of each opening (MEMS). Patients compliance was assessed both by standard pill-count and by electronic monitoring. Blood pressure was measured using a validated semi-automatic device at the end of the placebo period and of the treatment period. One hundred sixty-two patients entered the study. Compliance data were evaluable for 133 patients (62 in the captopril group and 71 in the trandolapril group). Treatment groups were comparable at baseline except for age (P = .046). Using electronic pill-box, overall compliance was 98.9% in the trandolapril group and 97.5% in the captopril group (P = .002). The percentage of missed doses was 2.6% in the trandolapril group and 3.3% in the captopril group (P = .06). The percentage of delayed doses was 1.8% in the trandolapril group and 11.7% in the captopril group (P = .0001). The percentage of correct dosing periods, ie, a period with only one correct recorded opening, was 94.0% in the trandolapril group and 78.1% in the captopril group (P = .0001). Results were unchanged when adjusted for age. At the end of the study, 41% of patients in the trandolapril group and 27% in the captopril group (NS) had their blood pressure normalized (systolic BP <140 and diastolic BP <90 mm Hg). In this 6-month study, the electronic pill-box allowed refined analysis of compliance of hypertensive patients. Patients compliance with once daily trandolapril was higher than with twice daily captopril. The between-group difference is mainly explained by an increase in delayed doses in the twice daily group.

Compliance and Antihypertensive Efficacy of Amlodipine Compared With Nifedipine Slow-Release

Poor compliance is a principal cause of treatment failure in hypertensive patients. Once-daily dosing improves compliance, but 24-h antihypertensive activity should be provided. The compliance, efficacy, and safety of amlodipine and nifedipine slow-release (SR) were compared in patients with mild-to-moderate essential hypertension recruited among 24 centers in France. After a 2-week washout period, 103 patients were randomized to 12 weeks of 5 to 10 amlodipine mg once daily (n = 55) or 20 mg nifedipine SR twice daily (n = 48). Compliance was calculated by electronic drug monitoring. Efficacy was measured by ambulatory and casual BP recordings. Patients receiving amlodipine demonstrated better compliance than patients receiving nifedipine SR with respect to compliance index (the total number of doses taken divided by the total number of doses prescribed, expressed as a percentage; 98.3% v 87%; P < .0001), days on which the correct number of doses were taken (92.5% v 74.8%; P < .0001), and prescribed doses taken on schedule (88.7% v 71.6%; P < .0001). Absolute and relative therapeutic coverage were higher in patients receiving amlodipine than nifedipine SR (P < .0001). Mean SBP and DBP decreased equally in both groups, although amlodipine offered better BP control compared with nifedipine SR at specific times of day. Fewer patients had high nocturnal SBP with amlodipine (39.3%) than nifedipine SR (71.4%; P = .042). Adverse events and treatment withdrawals occurred less frequently in amlodipine-treated patients than in nifedipine SR-treated patients. Amlodipine (5 to 10 mg) once daily provides improved compliance, better 24-h BP control, and fewer adverse events than 20 mg nifedipine SR twice daily in patients with mild-to-moderate hypertension.

A prospective study of helical computed tomography angiography versus angiography for the detection of renal artery stenoses in hypertensive patients

Objective To compare helical computed tomography angiography with arterial digital subtraction angiography in the diagnosis of renal artery stenoses. Methods Fifty hypertensives (24 men; mean age 53 years) were prospectively studied with computed tomography (Somaton Plus S, Siemens) and digital angiography (double-blind evaluation). Computed tomography was performed both in the sequential (the length of the abdomen) and in the helical (5 cm around renal arteries) modes during injection of 120 cm3 contrast medium. Results Digital angiography visualized 16 significant (< 50% on quantitative angiography) stenoses (16/131 renal arteries, including 32 accessory), in 14 (28%) patients. On helical computed tomography, 16 stenoses were detected, in 49 patients (16/122 renal arteries, seven accessory arteries were not identified because they were located out side the scan area); two patients had false-positive helical computed tomography results. The computed tomography sensitivity, specificity, positive and negative predictive values were 87.5% (14/16), 98.2% (111/114), 87.5% and 98.2%, respectively. In the sequential mode, two cases of bilateral adrenal hyperplasia, two aortic aneurysms and one renal neoplasm were detected. None of these patients had renal artery stenosis. Conclusions Helical computed tomography is a suitable new non-invasive diagnostic modality for the detection of renal artery stenosis or adrenal pathology. With continued development and evaluation computed tomography could prove useful as a screening tool or as a replacement for digital angiography in patients with possible secondary hypertension.

Doppler Flow Wire Evaluation of Renal Blood Flow Reserve in Hypertensive Patients with Normal Renal Arteries

AbstractPurpose: To study the vasomotor responses of the renal microcirculation in patients with essential hypertension.n Methods: We studied the reactivity of the renal microcirculation to papaverine, with intraarterial Doppler and quantitative arteriography, in 34 renal arteries of 19 hypertensive patients without significant renal artery stenosis. Isosorbide dinitrate was given to maximally dilate proximal renal arteries. APV (average peak blood flow velocity) was used as an index of renal blood flow.n Results: Kidneys could be divided into two distinct subgroups based on their response to papaverine. An increase in APV of up to 55% occurred in 21 kidneys, an increase > 55% in 13 kidneys. Within each group the values were normally distributed. Both baseline APV and the effect of papaverine on mean velocity differed significantly between groups.n Conclusion: There seems to be a subgroup of patients with essential hypertension that has an impaired reactivity to papaverine, consistent with a functional impairment of the renal microcirculation. Further studies are required to determine whether this abnormality contributes to or results from elevated blood pressure.

Renal atrophy in atherosclerotic renovascular disease: gradual changes 6 months after successful angioplasty.

Objective: To assess renal morphology using spiral computed tomographic angiography (CTA) before and 6 months after angioplasty of unilateral atherosclerotic renal artery stenosis (RAS). Methods: Spiral CTA scans from 14 hypertensive patients (7 men; mean age 57.4 ± 13.1 years) with significant RAS were performed before and 6 months after angioplasty; renal length, mean cortical thickness (MCT), cortical area (CA), and medullary length (ML) were measured from the axial slices in the 14 contralateral and 14 poststenotic then revascularized kidneys. Blood pressure, creatinine clearance, and number of antihypertensive drugs were analyzed. Results: At 6 months, the systolic blood pressure was significantly reduced (p=0.007), but the number of antihypertensive drugs and the creatinine clearance did not change significantly. Most morphological parameters before and after angioplasty were different in the contralateral versus poststenotic kidneys (renal length, p=0.01; MCT, p=0.01; ML, p=0.03; CA, p=0.008). After angioplasty, there was an 11% drop in cortical atrophy associated with a mean 4-mm increase in medullary length in the poststenotic/revascularized kidneys. The contralateral kidneys exhibited corticomedullary thinning after angioplasty. Conclusions: In atherosclerotic renal disease, cortical thinning could be a useful timesaving marker to assess the significance of the lesion and to evaluate associated distal lesions. The favorable blood pressure outcome supports the existence of reversible ischemic lesions, particularly in the medulla. Angioplasty appears to be useful for the poststenotic kidney, according to the morphological study.

Randomized, comparative, double-blind study of amlodipine vs. nicardipine as a treatment of isolated systolic hypertension in the elderly

A 90‐day, multicenter, randomized, double‐blind, parallel‐group study was conducted to compare the efficacy of amlodipine (once a day) with nicardipine (two to three times a day), in the treatment of isolated systolic hypertension (ISH) in the elderly. Patients (n = 133) aged ≥60 years, with ISH were randomized to receive either amlodipine 5 mg/day, or nicardipine 60 mg/day (titrated if necessary to 10 mg/day and 100 mg/day, respectively) for 90 days. Efficacy was assessed by measuring office blood pressure (BP), and 24‐h ambulatory blood pressure monitoring (ABPM). The two treatments substantially and comparably reduced office systolic blood pressure (SBP) and pulse pressure (PP), and also produced a slight decrease in diastolic blood pressure (DBP). Amlodipine reduced SBP, as assessed by ABPM, to a significantly greater extent than nicardipine. Both treatments were well‐tolerated. The sustained effect of amlodipine, compared with nicardipine, was reflected in its significantly greater antihypertensive activity, particularly during the nocturnal period, as assessed by ABPM. The study demonstrates that once a day dose of amlodipine is an effective antihypertensive treatment for elderly ISH patients.