A comparative study of effects of nebivolol and atenolol on blood pressure and lipid profile in patients of mild to moderate hypertension

Background: Beta blockers have been used in the treatment of hypertension, since last four decades and are widely accepted as the first-line treatment for hypertension. Nebivolol, a third generation β-blocker has highest β1 selectivity and is devoid of intrinsic sympathomimetic activity. Along with peripheral vasodilatation and nitric oxide (NO)-induced benefits such as antioxidant activity and reversal of endothelial dysfunction, nebivolol promotes better protection from cardiovascular events. The objective of the study was to compare the effects of atenolol and nebivolol on both blood pressure and lipid profile in patients of mild to moderate hypertension.Methods: This was a prospective, randomized, parallel, open labelled study. Patients were recruited from the medicine out-patient department (OPD) and cardiology OPD. A total of 100 patients were enrolled in the study. 50 patients were allocated to atenolol group and 50 patients to nebivolol group. BP and baseline investigations such as lipid profile were performed. Tests to determine lipid profile were performed on the first visit (Week 0) and at 24 weeks. Continuous variables between the two treatment groups were analyzed by unpaired t-test. Efficacy endpoints within the group were analyzed by using paired t-test.Results: All the lipid levels except HDL-C were increased with atenolol therapy. At 24 weeks, atenolol therapy led to increase in LDL-C, VLDL-C, TC and TG which was highly significant (p<0.0001). HDL levels were decreased at 24 weeks which was also statistically highly significant (p<0.0001). The mean values of lipids in nebivolol group at baseline and at 24 weeks. At 24 weeks, nebivolol therapy led to changes in LDL-C, VLDL-C, HDL-C, TC and TG which was not statistically significant (p>0.05).Conclusions: From study it can be concluded that atenolol and nebivolol are equally effective in reducing BP but atenolol worsens lipid profile as compared to nebivolol.

Prospective, randomized double blind comparative study of safety and efficacy of carvedilol versus atenolol in patients of mild to moderate hypertension

Background: Carvedilol is a new cardiovascular compound with the combined pharmacologic properties of nonselective ß-blockade and vasodilation. The Aim of the study was to compare the safety and antihypertensive efficacy of 25mg Carvedilol once daily with 50mg atenolol once daily in patients with mild to moderate essential hypertension.Methods: This was a single center study conducted in Rangaraya Medical College, Kakinada. 80 eligible patients with mild to moderate hypertension were randomized to receive 25mg Carvedilol once daily (40 patients) or 50mg atenolol (40 patients) in a double-blind 12-week treatment phase. At each visit 0, 4, 8 and 12 weeks of treatment, sitting Blood Pressure (BP) and heart rate were measured. The effect on BP reduction within the group is compared by paired “t”test and the effect on reduction of BP between two study groups compared by unpaired “t”test.Results: After 12 weeks of treatment, the mean reduction of SBP (Systolic Blood Pressure) with carvedilol is 22.33±8.31mmHg with no Significant difference (p >0.05) compared to atenolol group mean reduction in SBP of 21.37±10mm Hg. The mean reduction in DBP (Diastolic Blood Pressure) after completion of the study in carvedilol group is 6.75±4.82mm Hg with no Significant difference (p >0.05) compared to atenolol group mean reduction in DBP of 8.55±5.25mm Hg. No significant difference seen in the efficacy parameters of both the drugs. The incidence of adverse effects such as bradycardia, headache, nausea, vomiting, hypotension and rash is less with carvedilol.Conclusions: In patients with mild to moderate hypertension, there was no statistically significant difference between efficacy of carvedilol or atenolol with regard to the degree of reduction in BP or the percentage of patients achieving a response to therapy but carvedilol showed a better safety profile when compared to atenolol.

Autonomic modulation and chronotropic activity during aerobic exercise in patients using atenolol

Introduction: The negative chronotropic effect of beta-blockers (BB) can modify itself according to its pharmacokinetics. Objective: To investigate the influence of pharmacokinetics of beta-blockers in heart rate (HR) and autonomic activity (AA) in response to the exercise. Methods: Three groups of hypertensive patients, users of atenolol (n=9), enalapril, (n=8), and a normotensive control group (n=8), performed two sessions of moderate exercise on a cycloergometer, during 40 minutes, whereby 2 hours (Session I), or 23 hours after drug administration (Session II). Records of electrocardiogram were made before, during and after the exercises. Results: The HR was lower in session I comparing with session II of the atenolol group during the exercise. There were no differences in the components of low and high frequency of AA between these sessions. Conclusions: These results confirm the negative chronotropic effect of BB. However, the absence of changes in AA suggests that other mechanisms may be contributing to this phenomenon.

Time course of changes in carbohydrate and lipid metabolic parameters in patients with hypertensive disease during therapy with Rilmenidine versus Atenolol

The study has evaluated the impact of 26-week therapy with Rilmenidine, 1-2 mg daily, versus atenolol, 50-100 mg daily, on the parameters of 24-hour blood pressure monitoring, on the results of lipid phenotyping and oral glucose test in 37 patients with mild and moderate arterial hypertension (Stage II) during the randomized study. The antihypertensive effects of the drugs were comparable with a more significant decrease in heart rate in the atenolol group. At the same time, Rilmenidine showed good effects on the parameters of lipid metabolism and on the results of oral glucose tests as compared with atenolol whereas therapy with the latter resulted in deterioration of the blood lipid spectrum.

Glycemia in newborns of hypertensive mothers according to maternal treatment

PURPOSE: To evaluate the evolution of glycemic levels in newborns of hypertensive mothers according to maternal treatment. METHODS: Prospective randomized study, including 93 newborns of mothers treated with isradipine (n = 39), atenolol (n = 40), or low sodium diet (control group - n=14). Glycemia was determined at birth (mother and newborn by the oxidase glucose method) and in the 1st, 3rd, 6th, 12th, and 24th hours after birth (newborn by a test strip method). The evolution of glycemia was analyzed in each group (Friedman test). The groups were compared regarding glycemia (Kruskall-Wallis test), and linear regression models were constructed for the analyses (independent variable = maternal glycemia; dependent variables = umbilical cord, 3rd, and 6th hour glycemia). RESULTS: There were no statistically significant differences among the mean blood glucose levels of the 3 groups in any of the assessments. There was a correlation between maternal and umbilical cord blood glucose in the isradipine (r = 0.61; P <.05) and control (r = 0.84; P <.05) groups. Regarding glycemia levels of the mothers and newborns in the third and sixthhours postpartum, this correlation was present only in the control group (maternal x third hour: r = 0.65; P <.05; maternal x sixth hour: r = 0.68; P <.05). There were no correlations in the atenolol group. Hypoglycemia was detected in 51.3% of the isradipine group, 60% of the atenolol group, and 35.7% of the control group, and it was more frequent in the first hour postpartum in all groups. CONCLUSIONS: The results suggest a similar effect of the 3 types of treatment upon newborn glycemia. The correlation analysis suggests that isradipine could have effects upon newborn glycemia only after birth (correlation only in umbilical cord blood), whereas atenolol could act earlier (there was no correlation at any moment). The results also point to the need for glycemic control from the first hour postpartum of newborns of hypertensive mothers whether they have or have not undergone treatment with antihypertensive drugs.

Beneficial Effects from β-Adrenergic Blockade in Elderly Patients Undergoing Noncardiac Surgery

Background Perioperative beta-blockade has been shown to improve long-term cardiac outcome in noncardiac surgical patients. A possible mechanism for the reduced risk of perioperative myocardial infarction is the attenuation of the excitotoxic effects of catecholamine surges by beta-blockade. It was hypothesized that beta-blocker-induced alteration of the stress response was responsible for the reported improvements in cardiovascular outcome. Several variables associated with the perioperative use of beta-blockade were also evaluated. Methods Sixty-three patients were randomly assigned to one of three groups: group I, no atenolol; group II, pre- and postoperative atenolol; group III, intraoperative atenolol. Hormonal markers of the stress response (neuropeptide Y, epinephrine, norepinephrine, cortisol, and adrenocorticotropic hormone) were evaluated preoperatively and for 72 h after surgery. Results Perioperative beta-blockade did not significantly alter the hormonal stress response. However, the beta-blocked patients showed improved hemodynamic stability during emergence and postoperatively. They also received less fentanyl intraoperatively (27.7%, P &lt; 0.0001), experienced faster early recovery, had lower pain scores, and required less analgesia in the postanesthesia care unit. Cardiac troponin I release was detected in 8 of 19, 4 of 20, and 5 of 20 patients in groups I, II, and III, respectively (not significant). Three patients in group I had cardiac troponin I levels consistent with myocardial infarction. Conclusion Beta-blockade does not reduce the neuroendocrine stress response, suggesting that this mechanism is not responsible for the previously reported improved cardiovascular outcome. However, it confers several advantages, including decreased analgesic requirements, faster recovery from anesthesia, and improved hemodynamic stability. The release of cardiac troponin I suggests the occurrence of perioperative myocardial damage in this elderly population, which appears to be independent of the neuroendocrine stress response.

Prevention of Tachycardia with Atenolol Pretreatment for Carotid Endarterectomy under Cervical Plexus Blockade

A double-blind, randomised, controlled trial of forty patients was carried out to determine if oral atenolol pretreatment would reduce the incidence of tachycardia during carotid endarterectomy performed under cervical plexus block. Twenty patients received a placebo and twenty patients 50 mg of atenolol two hours prior to surgery. The superficial and deep cervical blocks were performed with 1.5% lignocaine containing 1:200,000 adrenaline. The patients were monitored with the V5 lead of the electrocardiogram and intraarterial blood pressure. These measurements were recorded on a correctly calibrated paper recorder. Tachycardia (heart rate > 90 beats per minute for more than three minutes) occurred in thirteen patients in the placebo group and two patients in the atenolol group (P<0.01). There was no difference in the occurrence of bradycardia, hypotension or hypertension between the two groups. It is concluded that atenolol pretreatment is an effective method of reducing the incidence of tachycardia during carotid endarterectomy performed under cervical plexus blockade.