Verapamil versus hydrochlorothiazide in the treatment of hypertension: results of long term double blind comparative trial. Verapamil versus Diuretic (VERDI) Trial Research Group

Prevalence, Recognition, and Risk Factors of Constipation among Medically Hospitalized Patients: A Cohort Prospective Study

Background and Objective: Constipation is a prevalent gastrointestinal condition that has a substantial impact on individuals and healthcare systems. This condition adversely affects health-related quality of life and leads to escalated healthcare expenses due to an increase in office visits, referrals to specialists, and hospital admission. This study aimed to evaluate the prevalence, recognition, risk factors, and course of constipation among hospitalized patients in medical wards. Materials and Methods: A prospective study was conducted, including all adult patients admitted to the General Medicine Unit between 1 February 2022 and 31 August 2022. Constipation was identified using the Constipation Assessment Scale (CAS), and relevant factors were extracted from the patients' medical records. Results: Among the patients who met the inclusion criteria (n = 556), the prevalence of constipation was determined to be 55.6% (95% CI 52.8-58.4). Patients with constipation were found to be older (p < 0.01) and had higher frailty scores (p < 0.01). Logistic regression analysis revealed that heart failure (Odds ratio (OR) 2.1; 95% CI 1.2-3.7; p = 0.01), frailty score (OR 1.4; 95% CI 1.2-1.5; p < 0.01), and dihydropyridines calcium channel blockers (OR 1.8; 95% CI 1.2-2.8; p < 0.01) were independent risk factors for constipation. Furthermore, the medical team did not identify constipation in 217 patients (64.01%). Conclusions: Constipation is highly prevalent among medically hospitalized patients. To ensure timely recognition and treatment, it is essential to incorporate a daily constipation assessment scale into each patient's medical records.

Verapamil ameliorates proximal tubular epithelial cells apoptosis and fibrosis in diabetic kidney

Diabetic kidney disease (DKD) is a severe complication of diabetes mellitus for which there is still no effective treatment. We previously showed that upregulation of thioredoxin-interacting protein (TXNIP), an endogenous inhibitor of thioredoxin (TRX), accelerates the progression of DKD. In this study, we hypothesized whether verapamil, a calcium channel blocker and an established TXNIP inhibitor, might exert a renal-protective effect on DKD by regulating TXNIP expression. Herein, a systemic pharmacological network study was performed and multiple molecules and pathways targeted by verapamil on DKD were characterized. Furthermore, diabetic mice were induced by streptozotocin (STZ), and verapamil (100 mg/kg/day) or saline was intraperitoneally injected into the mice. After 16 weeks, mice were analyzed for blood glucose, blood pressure, and functional parameters followed by sacrifice and evaluation of renal tubular injury, alterations in TXNIP, apoptosis and fibrosis markers. Additionally, the effects of treatment with verapamil (50 μM, 100 μM, 150 μM) under high glucose conditions on the expression of TXNIP and signaling pathway components in proximal tubular epithelial cells (PTEC, HK-2 cells) were explored. According to these findings, we conclude that verapamil might serve as a potential agent for the prevention and treatment of DKD.

Antihypertensive drugs and risk of cancer: network meta-analyses and trial sequential analyses of 324,168 participants from randomised trials

BACKGROUND

The risk of cancer from antihypertensive drugs has been much debated, with a recent analysis showing increased risk with angiotensin-receptor blockers (ARBs). We assessed the association between antihypertensive drugs and cancer risk in a comprehensive analysis of data from randomised clinical trials.

METHODS

We undertook traditional direct comparison meta-analyses, multiple comparisons (network) meta-analyses, and trial sequential analyses. We searched PubMed, Embase, and the Cochrane Central Register of Controlled Trials from 1950, to August, 2010, for randomised clinical trials of antihypertensive therapy (ARBs, angiotensin-converting-enzyme inhibitors [ACEi], β blockers, calcium-channel blockers [CCBs], or diuretics) with follow-up of at least 1 year. Our primary outcomes were cancer and cancer-related deaths.

FINDINGS

We identified 70 randomised controlled trials (148 comparator groups) with 324,168 participants. In the network meta-analysis (fixed-effect model), we recorded no difference in the risk of cancer with ARBs (proportion with cancer 2·04%; odds ratio 1·01, 95% CI 0·93-1·09), ACEi (2·03%; 1·00, 0·92-1·09), β blockers (1·97%; 0·97, 0·88-1·07), CCBs (2·11%; 1·05, 0·96-1·13), diuretics (2·02%; 1·00, 0·90-1·11), or other controls (1·95%, 0·97, 0·74-1·24) versus placebo (2·02%). There was an increased risk with the combination of ACEi plus ARBs (2·30%, 1·14, 1·02-1·28); however, this risk was not apparent in the random-effects model (odds ratio 1·15, 95% CI 0·92-1·38). No differences were detected in cancer-related mortality for ARBs (death rate 1·33%; odds ratio 1·00, 95% CI 0·87-1·15), ACEi (1·25%; 0·95, 0·81-1·10), β blockers (1·23%; 0·93, 0·80-1·08), CCBs (1·27%; 0·96, 0·82-1·11), diuretics (1·30%; 0·98, 0·84-1·13), other controls (1·43%; 1·08, 0·78-1·46), and ACEi plus ARBs (1·45%; 1·10, 0·90-1·32). In direct comparison meta-analyses, similar results were recorded for all antihypertensive classes, except for an increased risk of cancer with ACEi and ARB combination (OR 1·14, 95% CI 1·04-1·24; p=0·004) and with CCBs (1·06, 1·01-1·12; p=0·02). However, we noted no significant differences in cancer-related mortality. On the basis of trial sequential analysis, our results suggest no evidence of even a 5-10% relative risk (RR) increase of cancer and cancer-related deaths with any individual class of antihypertensive drugs studied. However, for the ACEi and ARB combination, the cumulative Z curve crossed the trial sequential monitoring boundary, suggesting firm evidence for at least a 10% RR increase in cancer risk.

INTERPRETATION

Our analysis refutes a 5·0-10·0% relative increase in the risk of cancer or cancer-related death with the use of ARBs, ACEi, β blockers, diuretics, and CCBs. However, increased risk of cancer with the combination of ACEi and ARBs cannot be ruled out.

Rationale and design of the International Verapamil SR/Trandolapril Study (INVEST): an Internet-based randomized trial in coronary artery disease patients with hypertension

OBJECTIVES

The primary objective of the International Verapamil SR/Trandolapril Study (INVEST) is to compare the risk for adverse outcomes (all-cause mortality, nonfatal myocardial infarction [MI] or nonfatal stroke) in hypertensive patients with coronary artery disease (CAD) treated with either a calcium antagonist-based or a noncalcium antagonist-based strategy.

BACKGROUND

Treatment recommendations for hypertension include initial therapy with a diuretic or beta-adrenergic blocking agent, for which reductions in morbidity and mortality are documented from randomized trials but are less than expected from epidemiologic data. For this reason, recent attention has focused on calcium antagonists or angiotensin-converting enzyme inhibitors. While these agents reduce blood pressure, outcome data from large randomized trials are lacking, but some case-control data, dominated by short-acting dihydropyridines, suggest an increased risk of cardiovascular events. These studies had methodologic limitations and did not differentiate among calcium antagonist types and formulations. Several studies differentiating among calcium antagonist types and an overview of published randomized trials show no increased risk with verapamil and suggestion for benefit in CAD patients.

METHODS

A total of 27,000 CAD patients with hypertension will be randomized at 1,500 primary care sites to receive either a calcium antagonist-based (verapamil) or beta-blocker/diuretic-based (atenolol/hydrochlorothiazide) antihypertensive care strategy. The study uses a novel, electronic "paper-less" system for direct on-screen data entry, randomization and drug distribution from a mail pharmacy linked to the coordination center via the Internet.

RESULTS

Contract negotiations with the United States and international sites are ongoing. Patients being enrolled are predominantly elderly (72% aged 60 years or older) men (54%), with either an abnormal coronary angiogram or prior MI (71%). In addition to hypertension, CAD and elderly age, most patients (89%) have one or more associated conditions (diabetes, dyslipidemia, smoking, cerebral or peripheral vascular disease, etc.) contributing to increased risk for adverse outcome. While 26% have diabetes, most of these are noninsulin dependent. Using the protocol strategies, target blood pressures (according to JNC VI) have been reached in 58% at the fourth visit, and as expected most (89%) are requiring multiple antihypertensive drugs.

CONCLUSION

The design and baseline characteristics of the initial patients recruited for a prospective, randomized, international, multicenter study comparing two therapeutic strategies to control hypertension in CAD patients are described.

Clinical pharmacokinetics of vasodilators. Part I

Understanding the mechanism of action and the pharmacokinetic properties of vasodilatory drugs facilitates optimal use in clinical practice. It should be kept in mind that a drug belongs to a class but is a distinct entity, sometimes derived from a prototype to achieve a specific effect. The most common pharmacokinetic drug improvement is the development of a drug with a half-life sufficiently long to allow an adequate once-daily dosage. Developing a controlled release preparation can increase the apparent half-life of a drug. Altering the molecular structure may also increase the half-life of a prototype drug. Another desirable improvement is increasing the specificity of a drug, which may result in fewer adverse effects, or more efficacy at the target site. This is especially important for vasodilatory drugs which may be administered over decades for the treatment of hypertension, which usually does not interfere with subjective well-being. Compliance is greatly increased with once-daily dosing. Vasodilatory agents cause relaxation by either a decrease in cytoplasmic calcium, an increase in nitric oxide (NO) or by inhibiting myosin light chain kinase. They are divided into 9 classes: calcium antagonists, potassium channel openers, ACE inhibitors, angiotensin-II receptor antagonists, alpha-adrenergic and imidazole receptor antagonists, beta 1-adrenergic agonist, phosphodiesterase inhibitors, eicosanoids and NO donors. Despite chemical differences, the pharmacokinetic properties of calcium antagonists are similar. Absorption from the gastrointestinal tract is high, with all substances undergoing considerable first-pass metabolism by the liver, resulting in low bioavailability and pronounced individual variation in pharmacokinetics. Renal impairment has little effect on pharmacokinetics since renal elimination of these agents is minimal. Except for the newer drugs of the dihydropyridine type, amlodipine, felodipine, isradipine, nilvadipine, nisoldipine and nitrendipine, the half-life of calcium antagonists is short. Maintaining an effective drug concentration for the remainder of these agents requires multiple daily dosing, in some cases even with controlled release formulations. However, a coat-core preparation of nifedipine has been developed to allow once-daily administration. Adverse effects are directly correlated to the potency of the individual calcium antagonists. Treatment with the potassium channel opener minoxidil is reserved for patients with moderately severe to severe hypertension which is refractory to other treatment. Diazoxide and hydralazine are chiefly used to treat severe hypertensive emergencies, primary pulmonary and malignant hypertension and in severe preeclampsia. ACE inhibitors prevent conversion of angiotensin-I to angiotensin-II and are most effective when renin production is increased. Since ACE is identical to kininase-II, which inactivates the potent endogenous vasodilator bradykinin, ACE inhibition causes a reduction in bradykinin degradation. ACE inhibitors exert cardioprotective and cardioreparative effects by preventing and reversing cardiac fibrosis and ventricular hypertrophy in animal models. The predominant elimination pathway of most ACE inhibitors is via renal excretion. Therefore, renal impairment is associated with reduced elimination and a dosage reduction of 25 to 50% is recommended in patients with moderate to severe renal impairment. Separating angiotensin-II inhibition from bradykinin potentiation has been the goal in developing angiotensin-II receptor antagonists. The incidence of adverse effects of such an agent, losartan, is comparable to that encountered with placebo treatment, and the troublesome cough associated with ACE inhibitors is absent.

Effects of bunazosin and atenolol on serum lipids and apolipoproteins in a randomised trial

The effects of bunazosin and atenolol on serum lipids and lipoproteins after 6 months of treatment were compared in this multicentric, double-blind, randomised trial. A total of 174 patients with mild to moderate essential hypertension from 15 hospitals in Germany and Poland was included in the study. Eighty-seven were treated with the alpha-receptor blocker bunazosin and the same number with the beta-blocker atenolol. Systolic and diastolic blood pressure decreased significantly in both groups, whereas only atenolol decreased pulse rate. In the bunazosin group HDL-cholesterol was significantly increased after 6 months of treatment, whereas all other analysed parameters remained unchanged. In the atenolol group total cholesterol, LDL-cholesterol, total triglycerides, apolipoprotein E, VLDL-cholesterol and VLDL-triglycerides were significantly increased after 6 months of therapy. There was a significant difference between bunazosin and atenolol for total cholesterol, HDL-cholesterol, LDL-cholesterol, VLDL-cholesterol, triglycerides, VLDL-triglycerides and apolipoprotein B levels. As a consequence, there was a significant difference in the atherogenic index of both groups. We conclude that bunazosin is favorable in the treatment of high blood pressure, because the coronary risk is not negatively influenced as shown for atenolol.

A comparison of the antihypertensive effectiveness of a combination of moexipril or sustained-release verapamil with low-dose hydrochlorothiazide

The antihypertensive effectiveness of moexipril, a new angiotensin-converting enzyme (ACE) inhibitor, and sustained-release verapamil (verapamil SR) in combination with low-dose hydrochlorothiazide was investigated in patients with moderate to severe (Stages II and III) essential hypertension. Of 147 patients treated for 4 weeks with hydrochlorothiazide 25 mg/day, 108 patients with sitting diastolic blood pressure (SDBP) of 100 to 114 mmHg were randomly assigned to receive either moexipril 7.5 mg/day (n = 56) or verapamil SR 180 mg/day (n = 52) in addition to hydrochlorothiazide 25 mg/day. After 4 weeks of treatment, doses of moexipril or verapamil SR were increased to 15 and 240 mg/ day respectively for patients with SDBP of > or = 90 mmHg. These patients were evaluated for an additional 8 weeks. Electrocardiograms, blood chemistries, blood counts, urinalysis, plasma renin activity, and plasma aldosterone levels were monitored during the study. Moexipril or verapamil SR, in combination with low dose hydrochlorothiazide, resulted in decreased blood pressure in the sitting and standing positions. No correlation between blood pressure response and baseline plasma renin activity was demonstrated. The results of this study indicate that both moexipril and verapamil SR produced an additive hypertensive effect when added to low-dose hydrochlorothiazide. These combinations were well tolerated by the patients and did not result in serious clinical and metabolic side effects.

Delayed hypotension after overdose of sustained release verapamil

We present the case of a 25-year-old woman who, although normotensive on presentation, had a severe hypotensive episode more than 12 h after initial ingestion of sustained release verapamil. Management of asymptomatic patients who have overdosed on a sustained release preparation of a calcium channel blocker is discussed.

Different effects of eicosapentaenoic acid and olive oil on blood pressure, intracellular free platelet calcium, and plasma lipids in patients with essential hypertension

In a randomized, double-blind, crossover study our specific aim was to examine the effects of a dietary fish oil or olive oil supplementation on blood pressure, intracellular free platelet calcium, plasma lipoproteins, and circulating vasoactive substances such as norepinephrine, epinephrine, and renin in patients with essential hypertension. Ten hypertensive patients (WHO classes I, II) were randomly assigned to receive 9 g fish oil or 9 g olive oil daily for 6 weeks after a 4-week baseline period. The 6-week treatment periods were separated by a 4-week wash-out. During treatment with fish oil diastolic blood pressure decreased from 103 +/- 1 to 98 +/- 2 mmHg (P < 0.05) but did not change significantly during olive oil intake. Systolic blood pressure was not affected by either treatment. Intracellular free platelet calcium decreased in patients receiving fish oil (from 102 +/- 8 nM to 86 +/- 6 nM, P < 0.05) but was not significantly altered by olive oil treatment. In contrast, the dose-response curve for thrombin-induced intracellular free platelet calcium was not altered by the fish oil enriched diet. Plasma triglycerides decreased by approximately 40% in the fish oil group while low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, and total cholesterol were not altered. Renin activity, norepinephrine, and epinephrine in plasma were not influenced by fish oil supplementation. We conclude that a moderate increase in dietary fish oil reduces diastolic blood pressure, intracellular free platelet calcium, and plasma triglycerides in patients with essential hypertension.(ABSTRACT TRUNCATED AT 250 WORDS)

Oral verapamil with chemotherapy for advanced non-small cell lung cancer: a randomised study

To determine if the chemotherapy resistance of non-small cell lung cancer could be modified by oral verapamil, 72 patients were entered into a randomised trial of verapamil plus chemotherapy vs the same chemotherapy alone. Verapamil 480 mg day-1 was given for 3 days starting 24 h prior to chemotherapy which consisted of bolus vindesine 7 mg followed by ifosfamide/mesna 5 g m-2 over 24 h, followed by mesna alone for a further 8 h. Cycles were repeated every 3 weeks for up to six courses. Sixty-six patients were eligible for tumour response analysis and responses occurred in 41% of those randomised to chemotherapy plus verapamil and in 18% of those randomised to chemotherapy alone (P = 0.057). Median survival from start of treatment was significantly better in the verapamil arm (P = 0.02). Toxicity of the combination of chemotherapy plus verapamil was principally neurological and was manageable. Thus the addition of oral verapamil to vindesine/ifosfamide chemotherapy is feasible and in this study was associated with improved outcome. Further confirmation of these observations is required in non-small cell lung cancer, a tumour characterised by resistance to conventional chemotherapy.

Individualised selection of antihypertensive therapy

Theoretically, it should be possible to match the requirements of individual patients with the pharmacological and clinical properties of the large number of antihypertensive drugs now available. The concept of automatic sequential stepped-care therapy is now largely outdated, but therapy of clinically important hypertension must be initiated with one agent. Diuretics remain a first-line option in the elderly and in Black patients, as do calcium antagonists. Outcome trials are available only for the elderly, and in these the benefits of initial diuretic therapy are well documented. Nonetheless, diuretics may often need to be co-prescribed with a beta-blocker or an adrenergic modifier such as methyldopa. beta-Blockers are preferred in patients with ischaemic heart disease or enhanced adrenergic drive, while alpha-blockers are preferred in patients with blood lipid abnormalities or prostatic problems. Calcium antagonists or angiotensin converting enzyme (ACE) inhibitors are being increasingly used as initial therapy when quality of life is important and metabolic neutrality is required. Calcium antagonists are more likely to be effective first-line therapy than ACE inhibitors in patients with a high salt intake, in patients with Raynaud's disease, when angina pectoris is present, and in Black patients. ACE inhibitors are preferred for combination with diuretic agents, and in the presence of congestive heart failure or low salt intake. Experimentally, both calcium antagonists and ACE inhibitors can prevent ischaemic ventricular fibrillation and atheroma. Combination therapy between these 2 drug classes is gaining increasing acceptance because of these theoretical advantages.(ABSTRACT TRUNCATED AT 250 WORDS)

Postinfarct treatment with verapamil. Effect of verapamil in patients with hypertension

In the Danish Verapamil Infarction Trial II (DAVIT II), treatment with verapamil 360 mg/day improved reinfarction-free survival compared with administration of placebo. Verapamil appears to effectively prevent reinfarction and sudden death, i.e. sudden events (hazard ratio 0.78 compared with placebo, 95% confidence limits 0.62 to 0.99). In a retrospective analysis of data from DAVIT II, verapamil treatment in patients with systemic hypertension prevented reinfarction significantly better than placebo (15 of 149 verapamil recipients compared with 27 of 152 placebo recipients reinfarcted, p = 0.04). Similarly, first cardiovascular events, i.e. first reinfarction, first stroke or death, were prevented more effectively by verapamil treatment than by administration of placebo (29 verapamil recipients vs 42 placebo recipients had first cardiovascular events, p = 0.07).

Choosing the correct drug for the individual hypertensive patient

With the availability of a wide selection of antihypertensive drugs acting by different mechanisms, it should be possible to match the requirement of individual patients with the pharmacological and clinical properties of an appropriate agent. Although the concept of stepped-care therapy is now largely outdated, therapy must be initiated with one agent. Diuretics remain a first-choice option in the elderly and in Black patients, as do calcium antagonists. In patients with ischaemic heart disease or enhanced adrenergic drive, beta-blockers are preferred. Calcium antagonists or ACE inhibitors are finding increasing use as initial therapy when quality of life is important and metabolic neutrality is required. The choice of antihypertensive agent may be limited by adverse effects, e.g. pedal oedema with nifedipine, constipation with verapamil, and cough with ACE inhibitors. Certain advantages are evident for both calcium antagonists and ACE inhibitors. Calcium antagonists are more likely to be effective first-line therapy than ACE inhibitors in Black patients, in those with a high salt intake, in patients with Raynaud's disease, and when angina pectoris is present. ACE inhibitors are preferred for use in combination with diuretic agents, and in the presence of congestive heart failure or low salt intake. Combination therapy between these 2 drug classes is finding increasing acceptance because of its many theoretical advantages, and may provide a means of maximising benefit.

Risk-benefit aspects of antihypertensive drugs

Several long term trials using traditional antihypertensive therapy with diuretics and beta-blockers have shown that antihypertensive therapy reduces the overall risk of cardiovascular complications. However, even after several years of therapy the cardiovascular risk in hypertensive patients cannot be lowered to that in the normotensive population. Antihypertensive therapy can reduce the incidence of cerebrovascular complications in patients with hypertension by about 65%. However, the effect of such therapy in preventing coronary events has been disappointing, as these events are 3 to 4 times more common than cerebrovascular complications in hypertensive patients. It is now apparent that adverse pharmacological effects of diuretics and beta-blockers on lipid metabolism persist for many years. Thus, treatment with these agents constitutes a new risk factor for coronary heart disease and may, at least in part, explain the failure of traditional antihypertensive therapy to reduce the incidence of myocardial infarction and sudden death as effectively as that of cerebrovascular accidents. On the other hand, titration of these antihypertensive agents to the lowest possible dose in order to avoid metabolic alterations and subjective adverse effects has frequently resulted in the administration of subtherapeutic doses, particularly for hydrochlorothiazide. Until comparative long term clinical trials with older and newer antihypertensive agents and morbidity and mortality as end-points are completed, the debate on first-line drugs for antihypertensive treatment will not be satisfactorily resolved.