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J Redon

Publications and source records attributed to J Redon.

51 records · Page 3Linked to original sources
PubMed1995

An equivalence study of the safety and efficacy of a fixed-dose combination of perindopril with indapamide versus fixed-dose combinations of captopril with hydrochlorothiazide and enalapril with hydrochlorothiazide in the treatment of hypertension.

OBJECTIVE: The aim of this multicenter, randomly allocated, double-blind, parallel-group study was to evaluate the equivalence of three fixed-dose combination drugs in mild to moderate hypertension: perindopril + indapamide (4 + 1.25 mg), captopril + hydrochlorothiazide (50 + 25 mg) and enalapril + hydrochlorothiazide (20 + 12.5 mg). PATIENTS AND METHODS: After a single-blind, 4-week, placebo run-in phase, 527 patients (mean +/- SD age 54.5 +/- 1.2 years) with a supine diastolic blood pressure of 101.2-101.7 mmHg were randomly assigned to one of the three treatments for 8 weeks. The main evaluation criteria were diastolic blood pressure and serum potassium concentration. Equivalence was assessed on an intention-to-treat basis, using Schuirmann's method, which involves performing two one-tailed statistical tests on the data. Thirty-five patients were withdrawn from the study but there were no differences between groups in the reasons for withdrawal. RESULTS: Diastolic blood pressure decreased by between 13.1 and 14.2 mmHg in the three groups. The 90% confidence intervals for the differences between perindopril + indapamide and the other treatments were -1.1, +1.7 mmHg for captopril + hydrochlorothiazide and -0.4, +2.6 mmHg for enalapril + hydrochlorothiazide. Schuirmann's test was highly statistically significant (P<0.001 for perindopril + indapamide versus captopril + hydrochlorothiazide; P<0.002 for perindopril + indapamide versus enalapril + hydrochlorothiazide), so that the two one-sided hypotheses that the treatments were not equivalent were rejected at the nominal level of alpha = 0.05. Similarly, the safety of the treatments was equivalent in terms of serum potassium. The 90% confidence intervals of the differences between perindopril + indapamide and the other treatments were -8.7, -1.6% for captopril + hydrochlorothiazide (P = 0.004) and -1.5, +2.7% for enalapril + hydrochlorothiazide (P<0.001). CONCLUSIONS: We conclude that the safety and efficacy of perindopril + indapamide, captopril + hydrochlorothiazide and enalapril + hydrochlorothiazide were equivalent after 8 weeks of treatment in patients with mild to moderate hypertension.

Adolescent↗
PubMed1994

Factors related to the presence of microalbuminuria in essential hypertension.

The objective of the present study was to assess factors related to the presence of microalbuminuria in essential hypertension. Ninety-five patients with essential hypertension (58 males and 37 females, mean age 38.6 +/- 6.1 years) who had never been treated previously for hypertension were included in the study. Patients with nephropathy or diabetes mellitus, hyperglycemia > 120 mg/dL, glomerular filtration rate < 80 mL/min/1.73 m2, urinary tract infection, or positive dipstick for albumin or glucose were excluded. Blood pressure, echocardiographically determined left ventricular mass, serum biochemistry, and lipid profile were obtained. Twenty-four-hour urinary albumin excretion (UAE) was measured on two separate days using an immunonephelometric assay. Microalbuminuria (UAE 30 to 300 mg/24 h) occurred in 26% of patients and was associated with higher diastolic blood pressure (DBP), left ventricular mass index (LVMI), and a higher prevalence of hypertriglyceridemia and hyperapolipoproteinemia B (apo-B). Logistic regression analysis showed that the risk of microalbuminuria was independently related to diastolic blood pressure and hypertriglyceridemia when controlling for age, sex, body mass index, LVMI, and apo-B. Multiple regression analysis likewise confirmed that both DBP and LVMI were linearly related to UAE independent of age, sex, body mass index, total cholesterol, triglycerides, and apo-B. In conclusion, our study indicates that among hypertensive patients with elevated excretion rates of urinary albumin, even at the subclinical level, an increased cardiovascular risk exists compared to normoalbuminuric patients with a similar blood pressure. Assessment of the presence of microalbuminuria may be useful in the evaluation and management of hypertension.

Adult↗
PubMed1994

Regulation of intracellular pH in the spontaneously hypertensive rat. Role of bicarbonate-dependent transporters.

Previous studies that have evaluated the Na(+)-H+ antiporter in cells from hypertensive subjects were generally performed under conditions in which HCO3-CO2, the physiological buffer system, was absent from the assay media. The objective of this study was to evaluate the activity of the Na(+)-H+ antiporter and that of the Na(+)-dependent and Na(+)-independent Cl(-)-HCO3- exchangers in cells assayed in the presence of HCO3-CO2 in the media. Lymphocytes from 6- to 8-week-old spontaneously hypertensive rats (SHR) and age-matched Wistar-Kyoto (WKY) rats were obtained from the thymus gland and assayed immediately after isolation. The activity of the Na(+)-H+ antiporter after stimulation by cell acidification (pHi approximately 6.4) was similar in SHR and WKY rats (18.67 +/- 1.03 and 16.12 +/- 0.92 mmol H+/L per minute, respectively). Recovery from cell alkalinization was effected by an Na(+)-independent Cl(-)-HCO3- exchanger, with maximal activity at an alkaline pHi (approximately 7.7). The stimulated activity of this Na(+)-independent Cl(-)-HCO3- exchanger was also not different between SHR and WKY cells (2.65 +/- 0.25 and 2.55 +/- 0.32 mmol H+/L per minute, respectively). Acute chloride removal produced a rise in pHi that was Na(+)-dependent and sensitive to 4,4'-diisothiocyanatostilbene-2,2'-disulfonic acid (DIDS) but resistant to ethylisopropylamiloride (EIPA), reflecting the activity of an Na(+)-dependent Cl(-)-HCO3- exchanger. Unlike the Na(+)-H+ exchanger and the Na(+)-independent Cl(-)-HCO3- exchanger, which had their highest activities at extremes of pHi (low pHi, Na(+)-H+ exchanger, and high pHi, Na(+)-independent Cl(-)-HCO3- exchanger), the Na(+)-dependent Cl(-)-HCO3- exchanger had its maximal activity near steady-state pHi (approximately 7.1). No significant differences were found in the stimulated activity of this exchanger between cells from SHR and WKY rats (2.23 +/- 0.26 and 2.50 +/- 0.43 mmol H+/L per minute, respectively). The kinetic properties of the Na(+)-dependent and Na(+)-independent Cl(-)-HCO3- exchanger, examined as a function of external Cl-, were also virtually identical in cells from SHR and WKY rats. We conclude that in lymphocytes from SHR and WKY rats, the activity of the two Cl(-)-HCO3- exchangers, like that of the Na(+)-H+ exchanger, is dependent on the prevailing pHi. The Na(+)-dependent Cl(-)-HCO3- exchanger has its highest activity near steady-state pHi, suggesting an important role in the cell defense against intracellular acidosis under physiological conditions.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed1994

Acid-base status and intracellular pH regulation in lymphocytes from rats with genetic hypertension.

This article reviews work from this laboratory dealing with acid-base status and intracellular pH (pHi) regulation in rat genetic models of hypertension. With freshly isolated thymic lymphocytes, pHi and its regulation were examined in the spontaneously hypertensive rat (SHR). In this rat model, pHi was found to be reduced as compared with that of lymphocytes from normotensive Wistar-Kyoto (WKY) rats. The activity of the Na+/H+ antiporter assessed after stimulation by acute cell acidification was similar in lymphocytes from SHR and WKY rats both in the nominal absence of HCO3- and in media containing HCO3- (22 mM). The kinetic properties of the Na+/H+ antiporter, examined as a function of pHi with the Hill kinetic model, revealed no significant differences between lymphocytes from SHR and WKY rats. The kinetic properties of the Na(+)-dependent and Na(+)-independent Cl(-)-HCO3- exchangers, examined as a function of external Cl-, were also virtually identical in lymphocytes from SHR and WKY rats. Unlike the Na(+)-H+ exchanger and the Na(+)-independent Cl(-)-HCO3- exchanger, which had their highest activities at extremes of pHi (low pHi, Na(+)-H+ exchanger; high pHi, Na(+)-independent Cl(-)-HCO3- exchanger), the Na(+)-dependent Cl(-)-HCO3- exchanger had its maximal activity near steady-state pHi. In Dahl/Rapp salt-sensitive rats with hypertension, the pHi of thymic lymphocytes was also reduced as compared with that of normotensive salt-resistant animals. In this model, renal net acid excretion in salt-sensitive rats was augmented as compared with that of salt-resistant rats. The increase in renal acid excretion was due to an increase in both ammonium and titratable acid excretion and was observed while animals were placed on high, normal and low salt diets. The findings of intracellular acidosis and enhanced renal acid excretion suggest that cellular acid overproduction is augmented in salt-sensitive hypertension.

Acid-Base Equilibrium↗
PubMed1994

Ambulatory blood pressure monitoring in normotensive children.

OBJECTIVE: To assess reference values of ambulatory blood pressure in normotensive children. SUBJECTS AND DESIGN: Twenty-four-hour non-invasive ambulatory blood pressure monitoring (ABPM) was carried out in 241 healthy normotensive children aged from 6 to 16 years (126 boys, mean +/- SD age 11.2 +/- 2.7 years; 115 girls, mean +/- SD age 10.9 +/- 2.9 years). The subjects were subdivided into three age-sex groups: 6-9, 10-12 and 13-16 years. SETTING: Primary care. MAIN OUTCOME MEASURES: ABPM was performed using an oscillometric device (SpaceLabs model 90207) and appropriate cuff size during a regular school day. Blood pressure was measured every 20 min from 0600 to 2400 h, and thereafter every 30 min. At each monitoring session the following parameters were calculated for both systolic (SBP) and diastolic blood pressure (DBP): means and centiles for 24-h, daytime (0800-2200 h) and night-time (2400-0600 h); circadian variability, estimated as the blood pressure fall between the day and the night periods and the day: night ratio; and load, as the percentage of measurements above the age- and sex-specific 95th centile (P95). RESULTS: The upper limits of 'normality' for the mean of 24-h SBP and DBP estimated as the P95 in each age subgroup were 121/71 and 119/71 mmHg, 123/78 and 120/74 mmHg, and 124/78 and 125/75 mmHg, for boys and girls, respectively. A progressive increase in SBP with age was observed in both sexes, in contrast, DBP was similar throughout the age range. A nocturnal blood pressure fall of approximately 11 mmHg was observed for both SBP and DBP in all subgroups. The day:night ratio was 1.12 and 1.22 for SBP and DBP, respectively. The upper limit of blood pressure load, estimated as the P95 in all children, was 39% for SBP and 26% for DBP. A significant positive correlation was observed between casual blood pressure and 24-h ambulatory blood pressure (SBP: r = 0.61, P < 0.0001; DBP: r = 0.31, P < 0.0001). In general, mean ambulatory blood pressure, during the 24-h or the daytime period, was higher than casual blood pressure for both SBP and DBP. CONCLUSION: ABPM is feasible in children, and the values obtained are useful as a departure point in establishing reference values.

Adolescent↗
PubMed1994

Ambulatory blood pressure and microalbuminuria in essential hypertension: role of circadian variability.

OBJECTIVE: To assess the relationship of subclinical urinary albumin excretion with ambulatory and circadian variability of blood pressure. DESIGN AND METHODS: Patients with essential hypertension (82 males and 59 females, mean +/- SD age 38.9 +/- 7.3 years) who had never been previously treated for hypertension were included in the study. Patients with nephropathy or diabetes mellitus, hyperglycemia > 120 mg/dl, glomerular filtration rate < 80 ml/min per 1.73 m2, urinary tract infection and positive dipstick for albumin or glucose were excluded. Twenty-four-hour ambulatory blood pressure monitoring on a regular working day using an oscillometric device was performed. Twenty-four-hour urinary albumin excretion was measured on two separate days using an immunonephelometric assay. RESULTS: Microalbuminuric patients (urinary albumin excretion 30-300 mg/24 h, n = 31) had significantly higher mean ambulatory systolic blood pressure (SBP) and diastolic blood pressure (DBP) than those with normoalbuminuria (urinary albumin excretion < 30 mg/24 h, n = 96) during the 24-h, daytime (0800-2200 h) and night (2400-0600 h) periods, whereas for office blood pressure only DBP was significantly higher. Urinary albumin excretion was positively correlated with the means of SBP and DBP. Multiple regression analysis similarly confirmed that DBP during daytime was positively and day:night ratio of DBP inversely associated with urinary albumin excretion independent of age, sex and other parameters of ambulatory blood pressure. CONCLUSIONS: In conclusion, the present study indicates that, in middle-aged essential hypertensive patients, the presence of microalbuminuria is a marker for the presence of higher values of blood pressure throughout a 24-h period.

Adult↗
PubMed1992

Is salt restriction necessary in hypertensive patients treated with calcium antagonists?

A moderate restriction of salt intake is recommended as a nonpharmacological approach to reducing high blood pressure, and can be used as an adjuvant to antihypertensive drug treatment. Noncompliance with a salt-restricted diet is the main limitation to this therapeutic approach. Evidence to date has shown that hypertensive patients treated with a calcium antagonist may not require a salt-restricted diet to achieve target blood pressure reductions. Further long term studies are required to confirm this.

Calcium Channel Blockers↗
PubMed1987

Drug fever.

Explore the source record for details and available documents.

Azathioprine↗
PubMedDate not supplied

Obesity, body fat distribution, and ambulatory blood pressure in children and adolescents.

Obesity is a common disease with an ever-increasing prevalence and usually with late-onset consequences. If acquired during childhood, it tracks into adult life to some extent, and since the relationship between obesity and hypertension is well established in adults, obese children appear to be at particularly high risk of becoming hypertensive adults. In the authors' study, obese children seemed to have significantly higher casual and ambulatory blood pressure than nonobese children, except for nighttime diastolic blood pressure. The health effects of obesity may depend on the anatomic distribution of body fat, which in turn may be a better indicator of endocrinologic imbalance, environmental stress, or genetic factors than is fatness per se. Subjects with a higher waist-to-hip ratio or a larger waist, as an estimate of central obesity, tend to have higher blood pressure values even during childhood. Prevention of the onset of obesity in early life may be important to reducing the risk of coronary heart disease in later life.

Adipose Tissue↗