New insights and new approaches for the treatment of essential hypertension: selection of therapy based on coronary heart disease risk factor analysis, hemodynamic profiles, quality of life, and subsets of hypertension

Diuretics in primary hypertension - Reloaded

Diuretics have long been cherished as drugs of choice for uncomplicated primary hypertension. Robust mortality and morbidity data is available for diuretics to back this strategy. Off-late the interest for diuretics has waned off perhaps due to availability of more effective drugs but more likely due to perceived lack of tolerance and side-effect profile of high-dose of diuretics required for mortality benefit. Low-dose diuretics particularly thiazide diuretics are safer but lack the mortality benefit shown by high-dose. However, indapamide and low dose chlorthalidone have fewer side-effects but continue to provide mortality benefit.

Effects on insulin action of adding low-dose thiazide to angiotensin-converting enzyme inhibitor in essential hypertension

Concern exists regarding adverse metabolic effects of antihypertensive agents. In the United States, diuretics are recommended first-line but additional agents, usually angiotensin-converting enzyme (ACE) inhibitors, are often required to meet blood pressure targets. We have previously shown that the combination of low-dose diuretic with an ACE inhibitor has detrimental effects on insulin action compared with ACE inhibitor alone in hypertensive type 2 diabetic patients. Our aim was to establish whether similar effects occur in nondiabetic hypertensive patients using this combination. A randomized double-blind placebo-controlled crossover design was used. After a 6-week run-in, when regular antihypertensive medications were withdrawn and placebo substituted, patients received captopril 50 mg twice daily with either bendroflumethiazide 1.25 mg (CB) or placebo (CP) for 12 weeks with a 6-week wash-out between treatments. Insulin action was assessed by hyperinsulinemic euglycemic clamp after the 6-week run-in and at the end of each treatment period. There were no differences between treatments in fasting glucose or insulin concentrations. Glucose infusion rates required to maintain euglycemia were the same with each treatment (CP 22.1±2.2 vs CB 22.2±2.2 μmol/kg per minute). There was no difference in endogenous glucose production in the basal state (CP 8.9±0.5 vs CB 9.5±0.7 μmol/kg per minute; P=0.23) or during hyperinsulinemia (CP 2.2±0.6 vs CB 1.5±0.3 μmol/kg per minute; P=0.30). In contrast to the situation in type 2 diabetes mellitus, ACE inhibitor combined with low-dose thiazide diuretic does not adversely affect insulin action when compared with ACE inhibitor alone in nondiabetic hypertensive patients.

EFFECTS OF QIGONG ON BLOOD PRESSURE, HIGH-DENSITY LIPOPROTEIN CHOLESTEROL AND OTHER LIPID LEVELS IN ESSENTIAL HYPERTENSION PATIENTS

This study investigated the effectiveness of Qigong on blood pressure and several blood lipids, such as high-density lipoprotein (HDL) cholesterol, Apolipoprotein A1 (APO-A1), total cholesterol (TC), and triglycerides (TG) in hypertensive patients. Thirty-six patients were randomly divided into either the Qigong group, or a wait-listed control group. Blood pressures decreased significantly after eight weeks of Qigong. The levels of TC, HDL, and APO-A1 were changed significantly in the Qigong group post-treatment compared with before treatment. In summary. Qigong acts as an antihypertensive and may reduce blood pressure by the modulation of lipid metabolism.

Impact of Qigong Exercise on Self-Efficacy and Other Cognitive Perceptual Variables in Patients with Essential Hypertension

OBJECTIVES

The purpose of this study was to investigate the impact of practicing qigong on middle-age subjects with essential hypertension. Impacts on blood pressure, reported self-efficacy, perceived benefit, and emotion were observed.

DESIGN

Thirty-six (36) adult volunteers were assigned to either a waiting list control or a qigong group that practiced two 30-minute qigong programs per week over 8 consecutive weeks.

RESULTS

Systolic and diastolic blood pressure was significantly reduced in members of the qigong group after 8 weeks of exercise. Significant improvements in self-efficacy and other cognitive perceptual efficacy variables were also documented in the qigong group compared to the original situation described above.

CONCLUSIONS

This pilot study demonstrates the positive effects of practicing qigong on controlling blood pressure and enhancing perceptions of self-efficacy.

Effects of Qigong on blood pressure, blood pressure determinants and ventilatory function in middle-aged patients with essential hypertension

This study was designed to measure changes in blood pressure (BP), urinary catecholamines and ventilatory functions of patients with mild essential hypertension after 10 weeks of Qigong (Shuxinpingxuegong). Fifty-eight patients volunteered to participate in this study and were randomly divided into either a Qigong group (n = 29), or a control group (n = 29). Systolic blood pressure and diastolic blood pressure decreased significantly in the Qigong group such that both became significantly lower after 10 weeks in the Qigong than in the control group. Also, there was a significant reduction of norepinephrine, metanephrine and epinephrine compared to baseline values in the Qigong group. The ventilatory functions, forced vital capacity and forced expiratory volume per sec, were increased in the Qigong group but not the control. These results suggest that Qigong may stabilize the sympathetic nervous system is effective in modulating levels of urinary catecholamines and BP positively, and in improving ventilatory functions in mildly hypertensive middle-aged patients.

The effect of different hypertension models on active avoidance learning

This study tested the effects of different hypertension models on active avoidance learning in rats. Three-month-old male Wistar rats were divided randomly into six groups as follows: control (C), sham operated (sham), two kidney-one clip (2K-1C), one kidney-one clip (1K-1C), deoxycorticosterone-salt (DOCA), and N-omega-nitro-L-arginine-methyl ester (L-NAME) groups. Mean arterial blood pressures were significantly higher in four hypertensive groups compared with control and sham groups. The active avoidance training results indicated that hypertension state is associated with learning impairment. Thiobarbituric acid-reactive substances (TBARS) were determined as an indicator of lipid peroxidation in brain and hippocampus. Additionally, brain and hippocampus nitrite levels were studied.

Which is more important for the efficiency of hypertension treatment: hypertension stage, type of drug or therapeutic compliance?

OBJECTIVES

Hypertensive patients are a heterogeneous population that can be distributed in groups showing different cardiovascular risk and benefit from treatment. This study examines the cost-effectiveness of arterial hypertension treatment by age, sex, arterial hypertension stage, type of drug used and level of treatment compliance.

DESIGN

Markov models combining absolute risks for stroke, coronary heart disease and all causes of death with relative risks from clinical trials and observational studies. Data on health costs were collected from hospitals and primary care settings in the Basque Country (Spain).

RESULTS

Cost-effectiveness ratios vary from 34,516 euros/quality adjusted life year (QALY) gained in 30-year-old women to 3,307 euros/QALY in 80-year-old men. A treatment compliance of 50% increases these values to 45,270 and 4,905 euros/QALY, respectively. Treatment of arterial hypertension stage II shows lower ratios (19,798 euros/QALY in 30-year-old women and 1,918 euros/QALY in 80-year-old persons). Cost-effectiveness ratios for arterial hypertension stage I vary from 645 euros/QALY in 80-year-old men for diuretics to 47,325 euros/QALY in 30-year-old women for inhibitors of the angiotensin converting enzyme.

CONCLUSIONS

There are large variations in the cost-effectiveness of arterial hypertension treatment depending on age, sex, arterial hypertension stage, drug used and compliance. Improvement of treatment compliance yields the greatest gain both in effectiveness and efficiency.

Alpha 1-blockers in hypertension

Hypertension is a heterogeneous disease and this is reflected in the marked variability in response to monotherapy. Co-administering antihypertensive therapies has several theoretical benefits, namely enhanced efficacy, improved tolerability, increased compliance and, in some cases, potentially beneficial changes in biochemical variables associated with increased cardiovascular risk, such as improvements in lipid profiles. alpha 1-Blockers, such as doxazosin, have several favourable properties which should be advantageous when used with other agents. Their mechanism of action is complementary to that of each of the other four main groups of antihypertensive drugs and, in each case, enhanced efficacy has been observed when alpha 1-blockade has been added to monotherapy with other drug classes. Synergistic effects have been seen when an alpha 1-blocker is administered together with either a calcium channel blocker or angiotensin-converting enzyme inhibitor. While alpha 1-blockers induce regression of left ventricular hypertrophy, the possibility of enhanced effects during multiple therapy has not been explored. alpha 1-Blockers exert positive effects on lipids (limited data suggest that they are able to reverse the deleterious lipid effects of diuretics and beta-blockers) and exert neutral or positive effects on glucose homeostasis. Further studies are needed to determine whether alpha 1-blockers can alleviate the adverse effects of beta-blockers or diuretics on glucose homeostasis. alpha 1-Blockers, when given concomitantly with other antihypertensive drugs, are well tolerated, conferring advantages with respect to patient compliance. The current data favour the use of alpha 1-blockers as an additional component of antihypertensive therapy, but further studies are needed to address the metabolic and end-organ effects of such treatment regimens.

Captopril does not improve insulin action in essential hypertension: a double-blind placebo-controlled study

OBJECTIVE

To compare the effect of captopril with that of placebo on peripheral and hepatic insulin action in essential hypertension, in light of evidence that insulin resistance is associated with cardiovascular risk.

DESIGN

Randomized, double-blind, placebo-controlled, crossover trial, with 8 week treatment periods of captopril and placebo preceded and separated by 6 weeks of placebo.

SETTING

Belfast teaching hospital.

PATIENTS

Eighteen Caucasian nondiabetic patients (10 males), aged under 65 years, with essential hypertension, recruited from general practices in the greater Belfast area.

INTERVENTIONS

Captopril at 50 mg twice a day or placebo twice a day for two 8 week treatment periods.

MAIN OUTCOME MEASURES

Peripheral and hepatic insulin sensitivity assessed by glucose clamps.

RESULTS

Fourteen patients completed the study. Mean (+/- SEM) levels of fasting glucose, fasting insulin and postabsorptive hepatic glucose production were similar after captopril and placebo (5.4+/-0.1 versus 5.4+/-0.1 mmol/l, 10.6+/-2.2 versus 9.5+/-1.1 mU/l, 11.2+/-0.6 versus 11.0+/-0.5 mmol/kg per min, respectively). During hyperinsulinaemia, hepatic glucose production was suppressed to comparable levels after both treatments (4.8+/-0.6 versus 4.3+/-0.6 mmol/kg per min) and exogenous glucose infusion rates required to maintain euglycaemia were also similar (30.0+/-2.6 versus 30.3+/-2.6 mmol/kg per min).

CONCLUSION

Captopril therapy in uncomplicated essential hypertension has no effect on peripheral or hepatic insulin sensitivity.

A randomized, placebo-controlled study of loop diuretics in patients with essential hypertension: the bumetanide and furosemide on lipid profile (BUFUL) clinical study report

This study was conducted to determine whether loop diuretics are more effective than placebo in reducing blood pressure without raising serum lipid levels, and whether bumetanide is more effective than furosemide in this respect. In a double-blind, 24-week placebo-controlled crossover study, 27 patients with essential hypertension were treated in four periods of 6 weeks each, including placebo twice, furosemide 40 mg daily, and bumetanide 1 mg daily. Several metabolic parameters, including serum lipid levels, and blood pressure were assessed. Overall levels of total cholesterol, triglycerides, and low-density lipoprotein (LDL) cholesterol were 5%, 12.4%, and 4.8% higher, respectively, during loop diuretic therapy than during placebo treatment. Overall systolic and diastolic blood pressure measurements were 12 mmHg and 4 mmHg lower, respectively, during loop diuretic therapy than during placebo treatment. Any added effect of bumetanide on serum lipid levels and blood pressure compared with furosemide, however, could not be confirmed. Our results indicate that the loop diuretics bumetanide and furosemide are effective in reducing blood pressure, and influence serum lipid levels markedly less than do thiazide diuretics or chlorthalidone. In addition, these results indicate that differences in blood pressure reduction and serum lipid levels between the two compounds were small and nonsignificant.

"Isolated" low high-density lipoprotein cholesterol

OBJECTIVE

To present information on the function, structure, and importance of high-density lipoprotein cholesterol (HDL-C) and to evaluate the current literature regarding the controversy of managing patients with an "isolated" low HDL-C concentration.

DATA SOURCE

A MEDLINE search was performed (1966-June 1996) to identify English-language clinical and review articles pertaining to HDL-C. Some articles were identified through the bibliography of selected articles. STUDY SECTION: All articles were considered for possible inclusion in the review. Pertinent information, as judged by the authors, was selected for discussion.

DATA EXTRACTION

Important historical lipid studies, recent review articles, and clinical trials involving therapy for HDL-C were evaluated.

DATA SYNTHESIS

The structure, function, and measurement of HDL-C and the state of an isolated low HDL-C are discussed for background. Lifestyle modification measures to increase HDL-C, medications to avoid, estrogen replacement, and lipid-altering agents used to raise an isolated low HDL-C are presented.

CONCLUSIONS

An isolated low HDL-C concentration poses a risk for coronary heart disease. The management of this state is controversial. The first step in management is in agreement with experts and includes lifestyle modification (e.g., weight reduction, diet, smoking cessation, aerobic exercise). Estrogen replacement therapy and discontinuance of drugs that secondarily lower HDL-C are additional treatment options. The use of lipid-altering agents has been used in some patients. Nicotinic acid appears to be an effective agent for an isolated low HDL-C. A large clinical trial evaluating the effect of treating an isolated low HDL-C for primary and secondary prevention of coronary events is needed.

Review: the effects of antihypertensive agents on serum lipids

Because various antihypertensive drugs adversely affect lipid metabolism, these drugs may increase associated risks for coronary artery disease and thus offset some of the beneficial effects of blood pressure reduction. In this paper the current literature regarding the effects of antihypertensive agents on serum lipids is reviewed. Differing effects of various classes of antihypertensives are assessed to further our understanding of this very important subject.

Ca(2+)-channel blockers modulate the expression of interleukin-6 and interleukin-8 genes in human vascular smooth muscle cells

Ca(2+)-channel blockers at therapeutic concentrations were shown to modulate several processes underlying inflammation, such as growth factor-mediated activation of genes coding for the low density lipoprotein receptor and 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase in human vascular smooth muscle cells (VSMC) (Block et al., 1991), and for interleukins in human mesangial cells (Roth et al., 1992). Two Ca(2+)-channel blockers, Manidipine (Roth et al., 1992) and Verapamil (Walz et al., 1990) have been shown to induce the expression of the gene coding for interleukin-6 (IL-6). Here we demonstrate that the four Ca(2+)-channel blockers, Amlodipine, Felodipine, Isradipine and Manidipine, at nanomolar concentrations, activate the transcription of the genes encoding IL-6 and IL-8 in primary human VSMC and fibroblasts. Ca(2+)-channel blocker-induced transcription is subsequently followed by secretion of the two ILs into the growth medium of the cells. In addition, we compared the action of the Ca(2+)-channel blockers with that of propranolol, a beta-adrenoceptor antagonist, or with furosemide, a diuretic, all of which are known to lower blood pressure. However, in contrast to the dihydropyridines, the two latter drugs failed to affect the expression of the two IL genes.

Comparison of the efficacy and safety of once-daily versus twice-daily formulations of diltiazem in the treatment of systemic hypertension. The Canadian Multicenter Diltiazem-CD Hypertension Trial Group

The efficacy and safety of optimally titrated once-daily (CD) and twice-daily (SR) diltiazem were compared in 111 patients with mild to moderate systemic hypertension [seated diastolic blood pressure (DBP) > or = 95 mmHg and < or = 114 mmHg] in a multicenter, randomized, double-blind, placebo run-in, parallel-group trial. Following a 4 week washout and placebo-controlled run-in period, patients were randomized to receive diltiazem CD 180 mg and matching placebo (n = 54), or diltiazem SR 90 mg bid (n = 57). Total daily doses were titrated from 180 mg to 360 mg to achieve a goal of seated DBP < 90 mmHg during a 6 week titration period. The patients continued to receive their optimal dose for a 6 week follow-up period. Ninety-six (96) patients (diltiazem CD: 47, diltiazem SR: 49) completed the study protocol, with 60% of the diltiazem CD and 55% of the diltiazem SR patients achieving the goal of seated DBP of < 90 mmHg (p = 0.685). Although significant decreases occurred in seated and standing measurements of diastolic and systolic BP and heart rate with treatment in both groups, there were no significant differences between treatment groups. Both medications were well tolerated, with a similar frequency of adverse effects [diltiazem CD: 24/54 (37%) patients; diltiazem SR: 24/57 (42.1%) patients] with the most frequently reported adverse effects being headache and edema.

Antihypertensive therapy targeted to the needs of the patient: focus on the renin-angiotensin system; older and newer agents

Antihypertensive drug therapy can lower blood pressure and prolong life, but many hypertensive patients continue to develop further risk factors and to die prematurely of heart disease. Antihypertensive drugs can also interfere with the patient's quality of life, and many are not compatible with the concomitant medical conditions of the patient and the medications taken to treat them. For these reasons, the antihypertensive therapy selected should meet the specific and complete needs of each patient, not just treat the high blood pressure. An analysis of the drugs that inhibit the renin-angiotensin system suggests that several of these drugs have a more favorable therapeutic profile than other classes of hypotensive agents. The newly developed receptor-site-specific blockers are expected to be tolerated better by hypertensive patients and, consequently, to enhance their quality of life. The first of the new class of nonpeptide blockers of the AT1 receptor, losartan--which has no partial agonist activity--is likely to have the advantages of the angiotensin-converting enzyme inhibitors without their adverse effects, notably cough. In selected patients, the AT1-receptor blockers could become the drugs of first choice for the management of hypertension.

Antihypertensive therapy with enalapril improves glucose storage and insulin sensitivity in hypertensive patients with non-insulin-dependent diabetes mellitus

A double-blind, placebo-controlled, 4-week trial was performed to determine the antihypertensive and metabolic effects of enalapril (20 to 40 mg/d) in 16 hypertensive patients with non-insulin-dependent diabetes mellitus (NIDDM) aged 55 +/- 2 years and with a body mass index of 29 +/- 1 kg/m2. Glucose utilization was determined after an overnight fast and during insulin stimulation at 0 and 4 weeks (methods: euglycemic clamp, [3-3H]glucose infusion, indirect calorimetry). Enalapril decreased systolic (166 +/- 4 v 152 +/- 5 mm Hg, P < .05) and diastolic (102 +/- 2 v 95 +/- 2 mm Hg, P < .05) blood pressure. Peripheral insulin sensitivity, ie, insulin stimulation of glucose utilization, increased approximately 30%, or by 4.3 +/- 1.7 mumol/kg.min (13.1 +/- 2.0 v 17.4 +/- 3.5 mumol/kg.min, P < .05, 0 v 4 weeks) during enalapril treatment, but remained unchanged during placebo treatment (15.4 +/- 2.8 v 15.3 +/- 2.7 mumol/kg.min, respectively). The increase in glucose utilization during enalapril treatment was fully explained by an increase of 4.1 +/- 1.7 mumol/kg.min in glucose storage (4.1 +/- 1.2 v 8.1 +/- 2.9 mumol/kg.min, P < .05) while glucose oxidation remained unchanged. High-density lipoprotein (HDL) cholesterol increased by 8% (P < .05) and hemoglobin A1c (HbA1c) improved slightly (7.7% +/- 0.7% v 7.3% +/- 0.7%, P < .05) in the enalapril group, but not in the placebo group. We conclude that enalapril improves insulin sensitivity by increasing glucose storage in hypertensive patients with NIDDM.(ABSTRACT TRUNCATED AT 250 WORDS)

Adverse interaction between clonidine and verapamil

OBJECTIVE

To report two cases of a possible adverse interaction between clonidine and verapamil resulting in atrioventricular (AV) block in both patients and severe hypotension in one patient.

CASE SUMMARIES

A 54-year-old woman with hyperaldosteronism was treated with verapamil 480 mg/d and spironolactone 100 mg/d. After the addition of a minimal dose of clonidine (0.15 mg bid), she developed complete AV block and severe hypotension, which resolved upon cessation of all medications. A 65-year-old woman was treated with extended-release verapamil 240 mg/d. After the addition of clonidine 0.15 mg bid she developed complete AV block, which resolved after all therapy was stopped.

DISCUSSION

An adverse interaction between clonidine and verapamil has not been reported previously. We describe two such cases and discuss the various mechanisms that might cause such an interaction. Clinicians should be acquainted with this possibly fatal interaction between two commonly used antihypertensive drugs.

CONCLUSIONS

Caution is recommended in combining clonidine and verapamil therapy, even in patients who do not have sinus or AV node dysfunction. The two drugs may act synergistically on both the AV node and the peripheral circulation.

Transcriptional activation of low density lipoprotein receptor gene by angiotensin-converting enzyme inhibitors and Ca(2+)-channel blockers involves protein kinase C isoforms

The pharmacological potency of angiotensin-converting enzyme (ACE) inhibitors (lisinopril and enalaprilat) on the transcription of low density lipoprotein receptor and 3-hydroxy-3-methylglutaryl-CoA reductase genes was examined in human vascular smooth muscle cells and compared with the action of Ca(2+)-channel blockers (manidipine, verapamil, and diltiazem). Analogous to Ca(2+)-channel blockers, nanomolar concentrations of enalaprilat or lisinopril stimulated the synthesis of low density lipoprotein receptor mRNA and amplified the transcription induced by recombinant platelet-derived growth factor BB. In contrast to Ca(2+)-channel blockers, ACE inhibitors did not alter the transcription of the 3-hydroxy-3-methylglutaryl-CoA reductase gene. Platelet-derived growth factor BB stimulated the translocation of delta and epsilon isoforms of protein kinase C. Similar to Ca(2+)-channel blockers, ACE inhibitors reduced the translocation of delta and epsilon isoforms of protein kinase C. Furthermore, ACE inhibitors and Ca(2+)-channel blockers inhibited platelet-derived growth factor BB-induced transcription of c-fos and c-jun genes. The findings suggest that increased de novo synthesis of mRNA low density lipoprotein receptor apparently involves the participation of delta and epsilon isoforms of protein kinase C and transcription factors c-Fos and c-Jun.

The effects of various antihypertensive agents on cardiovascular risk factors in patients with renal failure

Systemic cardiovascular diseases are the most important cause of morbidity and mortality among patients with chronic renal failure. Hypertension, lipid-profile abnormalities, glucose intolerance, and left ventricular hypertrophy are found in most patients with chronic renal failure and are responsible for the increased incidence of atherosclerosis. Hypertension is the risk factor most susceptible to treatment, but consideration must be given in selecting an antihypertensive agent not only to its effect on blood pressure but to its effects on the other risk factors. Improper selection could impair the long-term benefit of good blood pressure control by increasing the severity of the other cardiovascular risk factors and eventually worsening the prognosis of the chronic renal failure. The remaining renal function in patients not yet in end-stage renal failure deserves special consideration; an adequate antihypertensive regimen could potentially delay the need for dialysis.

Antihypertensive therapy in the geriatric patient: II. A review of the alpha1-adrenergic blocking agents

The prevalence of hypertension increases with age. Multiple physiologic factors are involved in the development of hypertension in the elderly. Alpha1-adrenergic blocking agents lower blood pressure through a reduction in total peripheral resistance. Prazosin, terazosin, and doxazosin have been shown to be equally effective in reducing blood pressure in older persons. The bioavailability, terminal elimination half-life, and volume of distribution of prazosin is increased in the elderly. Hybrid drugs, such as ketanserin, urapidil, and indoramin are also effective in lowering blood pressure. Ketanserin seems to have a greater effect on blood pressure reduction in persons older than 60 years of age. Alpha1-adrenergic blockers may be used safely in patients with diabetes, asthma, and hyperlipidemia.

Angiotensin-converting enzyme inhibitors as cardioprotective agents

This discussion of documented and possible cardioprotective effects of angiotensin-converting enzyme (ACE) inhibitors examines the variety of sites along the pathway to end-stage heart disease at which they might intervene. In addition to their antihypertensive activity, their effects on left ventricular hypertrophy, lipid profiles, and insulin sensitivity are discussed in comparison to the effects of other classes of antihypertensive agents on these risk factors. The ability of ACE inhibitors to prevent the progression of congestive heart failure and reduce mortality is documented and a summary of data demonstrating benefits of their use in postmyocardial infarction patients with low ejection fraction is presented.

Treatment of hypertension in the elderly

Treatment of hypertension in the elderly is beneficial, and benefit exceeds risk, but in some individuals it may be difficult to decrease blood pressure to goal or normotensive levels. Recent data suggest that the use of diuretics and, in some instances, beta-adrenergic inhibitors will reduce morbidity and mortality in elderly hypertensives and will probably not alter metabolic parameters to a clinically significant degree in most individuals.

A "lipo-protective" effect of a fixed combination of captopril and hydrochlorothiazide in antihypertensive therapy

Increases of triglycerides and total cholesterol have been reported during treatment with antihypertensive drugs, most notably with beta blockers and diuretics. ACE inhibitors, on the other hand, are not known for having a negative effect on lipid profile. To evaluate the effects of a fixed combination of captopril and hydrochlorothiazide on lipid metabolism, blood pressure, and quality of life, we performed an open prospective study. A total of 2,154 patients with or without hypercholesterolemia, but not receiving lipid lowering drugs, were enrolled. Of the 1891 evaluable patients at baseline, 34.1% had a moderate risk with total cholesterol between 5.2 and 6.5 mmol/l (mean 5.8 mmol/l) and 41.3% had a high coronary heart disease (CHD) risk with total cholesterol higher than 6.5 mmol/l (mean 7.3 mmol/l). After six months of treatment, the median cholesterol level in the moderate risk group decreased from 5.8 to 5.4 mmol/l (p less than 0.0003) and in the high risk group from 7.3 to 6.3 mmol/l (p less than 0.0001). Triglycerides also decreased, whereas high density lipoprotein (HDL) increased in both risk groups. Systolic and diastolic blood pressure fell as expected and quality of life improved. The fixed combination was well tolerated. We observed a significant improvement of lipid profile in patients with mild to moderate hypertension while undergoing treatment with the fixed combination of captopril and hydrochlorothiazide. We suggest that captopril may balance the negative effects of hydrochlorothiazide on lipid metabolism in patients with hypertension and concomitant hyperlipidemia.

Sustained antihypertensive activity of diltiazem SR: double-blind, placebo-controlled study with 24-hour ambulatory blood pressure monitoring

A new polymeric matrix technology provides a sustained-release formulation of diltiazem hydrochloride (diltiazem SR) suitable for once-daily therapy. The efficacy and safety of diltiazem SR were evaluated in a multicenter, randomized, double-blind, placebo-controlled, parallel-group study. After a single-blind, placebo lead-in period, 275 patients with mild to moderate essential hypertension were assigned to receive placebo or diltiazem SR 120, 240, 360, or 480 mg once daily for 4 weeks. The efficacy evaluation was based on office and 24-hour ambulatory blood pressure monitoring. Twenty-four hours after the last dose in the 4-week, double-blind treatment period, the mean reduction from baseline in supine diastolic blood pressure ranged from 5.1 to 10.6 mm Hg in the diltiazem SR 120- to 480-mg groups, resulting in a significant linear trend across all treatments (P less than .001). Reductions in systolic blood pressure were similar. Ambulatory blood pressure monitoring, performed in 138 patients, confirmed the dose-response relationship and showed consistent antihypertensive activity throughout the 24-hour dosing interval. The percentage of patients reporting adverse events was similar in the placebo- and active-treated groups. The results of this study indicate that diltiazem SR is well tolerated, lowers blood pressure in a dose-related manner, and provides sustained activity throughout the 24-hour dosing interval.

Hypertension, coronary artery disease and insulin resistance--linked disorders with an impact on treatment

Coronary artery disease is a very common disorder for which hypertension is a well-recognized risk factor. However many trials of antihypertensive therapy have failed to demonstrate a reduction in the incidence of coronary events. One explanation is that hypertension is a disorder associated with hyperinsulinaemia, obesity and non-insulin dependent diabetes. Furthermore certain antihypertensive drugs, notably thiazide diuretics, increase the hyperinsulinaemia and thereby increase one of the other coronary risk factors. In this review the links between hypertension and hyperinsulinaemia are explored and the mechanisms whereby an increased plasma insulin can lead to the more rapid development of coronary artery disease are explained. These observations may influence the choice of drugs used to treat hypertension.

Accurate measurement of serum total cholesterol: the need for standardization

Heightened awareness of the importance of cholesterol and heart disease has increased cholesterol testing in the United States. The demand for reliable cholesterol measurements has become a focal concern of the patient as well as the clinician. This paper covers the major analytical and preanalytical issues and factors that can affect the reliability of cholesterol results. We discuss factors that lead to impression and inaccuracy; solutions for some of the major problems; resources and techniques to help standardize cholesterol measurement; and preanalytical issues that can affect cholesterol results--i.e., patient preparation; collection, processing, storage and proper analysis of the specimen; biological and seasonal variations; age and gender; diet; alcohol consumption; weight changes; exercise; primary diseases; and infections and trauma. Many of these can be controlled by the physician, resulting in more reliable cholesterol readings under stable metabolic conditions. Accurate values will help to classify the patient's coronary heart disease risk, define appropriate treatment strategies, and simplify monitoring of dietary and/or drug intervention.

New insights and approaches to reduce end-organ damage in the treatment of hypertension: subsets of hypertension approach

Antihypertensive therapy should be directed toward reduction of all end-organ damage including congestive heart failure, left ventricular hypertrophy, coronary heart disease, myocardial infarction, cerebrovascular accident, and chronic renal failure. The Subsets of hypertension approach is based on pathophysiology, hemodynamics, risk factor reduction for end-organ damage, concomitant diseases and problems, demographics, adverse effects on quality of life, compliance, and total health care costs. This approach provides a more individualized and logical treatment of the hypertensive syndrome and addresses the metabolic and structural abnormalities that are present.

A dose-response trial of once-daily diltiazem

This trial was performed to determine the safe and effective dosage range of once daily diltiazem (diltiazem CD) capsules for treatment of essential hypertension. Patients with essential hypertension having supine diastolic blood pressure values greater than or equal to 95 mm Hg and less than or equal to 110 mm Hg were randomly assigned to receive placebo or one of four doses of diltiazem CD: 90, 180, 360, or 540 mg. Blood pressure was measured at trough, 24 hours after the dose, and at the time of peak effect, 10 hours after the dose. Diltiazem CD lowered both supine diastolic and systolic blood pressure. A linear dose response was seen with changes in diastolic and systolic blood pressure and heart rate for trough and peak measurements. Trough/peak ratios for the 180, 360, and 540 mg doses were all greater than 0.50. Adverse effects were dose related; those most commonly reported were headache (8.6%), bradycardia (8.1%), and edema (7%), with bradycardia and edema possibly dose related. It is therefore concluded that diltiazem CD is a safe and effective antihypertensive agent.

Pharmacy Services in a Hypertension Clinic

Roles for pharmacists are evolving rapidly in the ambulatory care setting. This is primarily due to increasing inpatient costs with a resultant shifting of costs to the outpatient section. This shift has subsequently presented larger numbers of patients and sicker patients to the outpatient setting. This article describes the involvement of a clinical pharmacist in a multidisciplinary hypertension clinic. Detailed are the procedures used to evaluate a patient from consult to discharge, and the responsibilities of the clinical pharmacist, the clinic physician, and the nurse practitioner are reviewed. Finally, methods of documentation and quality assurance are outlined.