Prevention of type 2 diabetes mellitus through inhibition of the Renin-Angiotensin system

Optimizing the treatment of hypertension and stable coronary artery disease: clinical evidence for fixed-combination perindopril/amlodipine

BACKGROUND

Optimized management of hypertension and coronary artery disease (CAD) improves cardiovascular risk and outcomes, and prevents complications. This article reviews evidence for the fixed combination of the angiotensin-converting enzyme (ACE) inhibitor perindopril and the calcium channel blocker amlodipine.

METHODS

A literature search was performed in PubMed/MEDLINE to identify articles published in English between 1988 and March 2008 describing clinical trials, particularly outcome trials, or mechanisms of therapeutic action relevant to the use of combination therapy in patients with hypertension or stable coronary artery disease with an ACE inhibitor (perindopril) and a calcium channel blocker (amlodipine).

FINDINGS

Clinical trials indicate that this combination may have a positive impact on cardiovascular mortality and morbidity in hypertensive individuals. The two complementary mechanisms of action appear to work in synergy, leading to more efficient blood pressure lowering, improved fibrinolytic function, and reduction of secondary effects. This also represents a simplified management strategy for stable CAD. Perindopril has proven efficacy in the prevention of cardiovascular events and mortality in CAD patients, while amlodipine is widely used in the symptomatic management of CAD. Both aspects of guideline-recommended management of CAD are therefore addressed in a single tablet.

CONCLUSIONS

The clinical evidence for fixed-combination perindopril/amlodipine indicates it as a credible option for the optimization of the management of hypertension and CAD.

Angiotensin inhibition stimulates PPARgamma and the release of visfatin

BACKGROUND

Angiotensin converting enzyme inhibitors (ACE-I) and angiotensin receptor blockers (ARB) exhibit beneficial antidiabetic effects in patients with type 2 diabetes independent of their blood pressure-lowering effects. Some antidiabetic properties of ARB and ACE-I might by exerted by activation of peroxisome proliferator-activated receptor gamma (PPARgamma). However, it is not clear whether this action is drug specific.

MATERIALS AND METHODS

The binding affinity of telmisartan, valsartan, lisinopril, rosiglitazone and angiotensin II to PPARgamma was assessed in a cell-free assay system. PPARgamma signalling was studied in isolated skeletal muscle cells using Western blot analysis of phosphorylated protein kinase B (pAKT) and phosphorylated insulin like growth factor-1 receptor (pILGF-1R). Further, the ability of the drugs under study to stimulate the release of the adipocytokine visfatin was investigated in isolated human adipocytes, skeletal muscle cells, and umbilical vein endothelial cells (HUVEC).

RESULTS

The binding affinity to PPARgamma was highest for telmisartan with a half-maximal effective concentration of 463 nM, followed by lisinopril (2.9 microM) and valsartan (6.2 microM). In skeletal muscle cells phosphorylation of ILGF-1R was 2-fold increased after incubation with telmisartan or valsartan and 1.7-fold with lisinopril. pAKT expression was enhanced after incubation with telmisartan, valsartan and with lisinopril. The release of visfatin from adipocytes was 1.6-fold increased after treatment with lisinopril and about 2.0-fold increased with telmisartan and valsartan. Similar results were obtained in skeletal muscle cells and HUVEC.

CONCLUSIONS

Our data confirm agonism of telmisartan, valsartan and lisinopril on PPARgamma. Pharmacokinetic differences may explain different potencies of PPARgamma stimulation by drugs acting on the renin-angiotensin system in clinical settings.

The angiotensin II receptor blocker telmisartan improves insulin resistance and has beneficial effects in hypertensive patients with type 2 diabetes and poor glycemic control

The angiotensin II receptor blocker (ARB) telmisartan has a molecular structure that confers it partial agonist properties similar to those of peroxisome proliferators-activated receptor-gamma molecule, which is thought to modulate tissue response to insulin. In order to investigate the effects of telmisartan on insulin sensitivity and glucose metabolism, we enrolled 14 hypertensive patients under treatment with ARB other than telmisartan who had insulin resistance [homeostasis model for insulin resistance (HOMA-IR)>2.0] but no severe glucose tolerance (HbA1c<6.5%), and HOMA-IR was compared before and after the displacement by telmisartan. We also enrolled 27 obese (body mass index>25kg/m(2)) and hypertensive patients with type 2 diabetes under treatment with ARB other than telmisartan, and HbA1c was assessed before and after the displacement by telmisartan. The telmisartan significantly improved HOMA-IR in hypertensive patients and also significantly decreased HbA1c in type 2 diabetic patients especially in the patients with poor glycemic control (HbA1c>==8.0%). These results indicate that telmisartan improves insulin resistance and gives beneficial effects in hypertensive patients with type 2 diabetes and a poor glycemic control.

Efficacy and safety of fixed combinations of irbesartan/hydrochlorothiazide in hypertensive women: the inclusive trial

OBJECTIVE

This post hoc analysis of the Irbesartan/Hydrochlorothiazide Blood Pressure Reductions in Diverse Patient Populations (INCLUSIVE) trial evaluated the efficacy and safety of irbesartan/hydrochlorothiazide (HCTZ) in a diverse population of hypertensive women.

METHODS

INCLUSIVE was a multicenter, prospective, open-label, single-arm trial. Adult subjects had uncontrolled systolic blood pressure (SBP 140-159 mm Hg; 130-159 mm Hg for those with type 2 diabetes mellitus [T2DM]) after > or =4 weeks of antihypertensive monotherapy. Treatment was sequential: placebo (4-5 weeks), HCTZ 12.5 mg (2 weeks), irbesartan/HCTZ 150/12.5 mg (8 weeks), and irbesartan/HCTZ 300/25 mg (8 weeks). Mean changes from baseline to treatment end in SBP and diastolic blood pressure (DBP), BP goal attainment, and safety were assessed.

RESULTS

Treatment with irbesartan/HCTZ was associated with significant mean reductions in BP (intent-to-treat population, n = 370; SBP/DBP: -22.9/-10.3 +/- 14.7/8.8 mm Hg). Improvements in SBP were observed in all subgroups (p < 0.001): Caucasian (n = 207) -23.5 +/- 13.5 mm Hg; African American (n = 93) -21.0 +/- 17.2 mm Hg; Hispanics/Latino (n = 66) -23.6 +/- 14.3 mm Hg; age <65 years (n = 281) -22.5 +/- 14.7 mm Hg; age > or =65 years (n = 89) -24.3 +/- 14.5 mm Hg; T2DM (n = 97) -19.0 +/- 15.1 mm Hg; and metabolic syndrome (n = 187) -22.1 +/- 14.6 mm Hg. Overall, 82% (95% confidence interval [CI] 78%-86%) of women achieved their SBP goal, 86% (95% CI 83%-90%) achieved their DBP goal, and 76% (95% CI 71%-80%) achieved their dual SBP/DBP goal. Treatments were well tolerated in all groups.

CONCLUSIONS

Irbesartan/HCTZ treatment was effective and well tolerated in a diverse population of women whose BP was previously uncontrolled on monotherapy.

Loss of angiotensin-converting enzyme 2 leads to impaired glucose homeostasis in mice

This study aimed to investigate the role of angiotensin-converting enzyme 2 (ACE2) in regulating glucose homeostasis. Immunohistochemistry was used to investigate ACE2 expression in the pancreas. Glucose tolerance test, insulin secretion test, and insulin tolerance test were performed in age-matched male ACE2 knockout (KO) and wild-type (WT) mice. We found that ACE2 was positively expressed in the pancreas. Male ACE2 KO mice displayed a selective decrease in first-phase insulin secretion in response to glucose and a progressive impairment of glucose tolerance compared with age- and sex-matched WT mice. On the other hand, insulin sensitivity of the peripheral tissue in age-matched ACE2 KO and WT mice showed no difference. These findings suggest that ACE2 might play an important role in glucose homeostasis as well as type 2 diabetes.

Review: The therapeutic role of RAS blockade in chronic heart failure

Cardiovascular disease represents a continuum that starts with risk factors such as hypertension and progresses to atherosclerosis, end-organ damage, and ultimately to chronic heart failure (CHF) and premature death. Renin-angiotensin system (RAS) blockade with angiotensin converting enzyme (ACE) inhibitors and/or angiotensin II type 1 receptor blockers (ARBs) has turned out to be beneficial at all stages of this continuum. Several mechanisms govern the progression of structural myocardial damage to end-stage CHF. Chronic neuroendocrine activation fosters left ventricular remodeling and dilatation and leads to clinical symptoms of CHF via forward/backward failure. RAS inhibition is a cornerstone of neuroendocrine blockade in CHF patients, and combined RAS blockade is especially effective in patients presenting with repetitive cardiac decompensations. This review focuses on the therapeutic role of inhibitors of different RAS components in chronic heart failure caused by systolic left ventricular dysfunction.

Prediabetes: a must to recognise disease state

Prediabetes mellitus (PDM) is defined as a state of abnormal glucose homeostasis in which deficiency or resistance to insulin is the hallmark. PDM precedes the development of overt type 2 DM. It is associated with increased mortality and morbidity and thus fits well with the criteria of a disease condition. Framing PDM as a disease and not a risk or a 'pre' stage for diabetes is needed to facilitate early management.

AIM

This review aims therefore to increase awareness of PDM as a disease state.

METHODS

To do so, we shall preview guidelines for its diagnosis. Its prevalence and hazards will be then discussed. Finally, we shall elaborate on the current treatment guidelines.

RESULT

Enough evidence support the notion that PDM is a curable disease state.

CONCLUSIONS

The current recommendations for the treatment of PDM should be adhered. In addition, there is a room for the use of other pharmacological agents.

Preserving insulin secretion in Type 2 diabetes mellitus

Type 2 diabetes mellitus (T2DM) is a complex disease characterized by insulin resistance and a progressive decline in β-cell function and mass. Current evidence suggests that β-cell dysfunction is present early in the course of the disease and that this dysfunction, rather than insulin resistance, is primarily responsible for the progression of T2DM. β-cell dysfunction can be accelerated by glucose toxicity, lipotoxicity, oxidative stress, chronic increases in inflammatory mediators and, potentially, the use of sulfonylureas. This review suggests that future efforts to limit the impact of T2DM must focus on strategies to preserve β-cell function. Several interventions have shown promise in this regard, including lifestyle modifications, thiazolidinediones, potassium channel openers, incretin mimetics, cytokine antagonists, bariatric surgery and dipeptidyl peptidase IV inhibitors, although therapeutic insulin remains the most robust and physiological approach.

Blocking the renin-angiotensin-aldosterone system to prevent diabetes mellitus

Type 2 diabetes mellitus (DM) is increasing around the world, and the public health impact of DM, driven largely by cardiovascular disease complications, underpins the importance of continued efforts toward primary prevention of DM. Only a few interventions have been shown to prevent DM, with none of them yet proven to improve cardiovascular risk commensurately. Accumulating evidence suggest that drugs that block the renin-angiotensin-aldosterone system (RAAS), many of which have proven cardiovascular disease (CVD) benefit, also have favourable effects on parameters of glucose metabolism and incident diabetes. Here we review the evidence accumulated to date from animal studies, clinical mechanistic studies and clinical trials regarding the effect of RAAS inhibition and incident DM.

Telmisartan improves endothelial function in patients with essential hypertension

BACKGROUND

: Hypertension is a cardiovascular risk factor commonly associated with endothelial dysfunction and increased renal vascular resistance. Angiotensin receptor blockers (ARBs) may beneficially affect these parameters via antagonism of angiotensin type 1 (AT1) receptor-mediated vasoconstriction and vascular superoxide production. We therefore investigated whether the new ARB telmisartan improves endothelial function and renal vascular resistance in patients with essential hypertension.

METHODS

: Thirty-seven patients with essential hypertension were randomized to receive telmisartan, the calcium channel blocker nisoldipine, or their combination for 6 weeks in a prospective, parallel group study. Brachial artery flow-mediated (endothelium-dependent) dilation (FMD) and renal vascular resistance index (RVRI) were evaluated using high-resolution ultrasound before, at 3 weeks (low dose), and at 6 weeks (high dose) after initiation of treatment.

RESULTS

: At baseline, FMD and RVRI did not significantly differ between treatment groups. After 3 weeks of treatment neither treatment significantly changed FMD or RVRI. After 6 weeks of treatment, patients randomized to receive telmisartan alone or the combination, but not those treated with nisoldipine alone, displayed a significantly improved FMD, whereas RVRI values again were not significantly different as compared to those at baseline.

CONCLUSION

: In our study cohort of patients with essential hypertension, treatment with telmisartan improved FMD but did not change RVRI. Future studies will demonstrate whether this telmisartan-induced effect may contribute to a blood pressure-independent reduction in cardiovascular morbidity.

Metabolic side effects and cardiovascular events of diuretics: should a diuretic remain the first choice therapy in hypertension treatment? The case of yes

Essential hypertension is a major cause of cardiovascular morbidity and mortality in the Western world. Numerous clinical trials have demonstrated that the treatment of hypertension results in a substantial reduction of hypertension-related morbidity and mortality. The efficacy and safety of diuretics has been shown in many clinical trials. Like most other antihypertensive agents, the side effects of diuretics are mostly benign and mild. The metabolic side effects of diuretics, however, have been a bone of contention for a long time. In this paper, we describe the most important and frequent metabolic side effects of diuretics, and emphasize particularly the non-life-threatening effect of diuretics on ventricular arrhythmias due to their hypokalemic effect, the detection of the new onset diabetes (perhaps caused by the administration of diuretics itself), and their significant beneficial effect on cardiovascular and cerebrovascular morbidity and mortality. At the end of the article, we highlighted the differences regarding the prescription of diuretics between the recently published American and European Guidelines of hypertension.

Metabolic and clinical outcomes in nondiabetic individuals with the metabolic syndrome assigned to chlorthalidone, amlodipine, or lisinopril as initial treatment for hypertension: a report from the Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT)

OBJECTIVE

Optimal initial antihypertensive drug therapy in people with the metabolic syndrome is unknown.

RESEARCH DESIGN AND METHODS

We conducted a subgroup analysis of the Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT) to compare metabolic, cardiovascular, and renal outcomes in individuals assigned to initial hypertension treatment with a thiazide-like diuretic (chlorthalidone), a calcium channel blocker (CCB; amlodipine), or an ACE inhibitor (lisinopril) in nondiabetic individuals with or without metabolic syndrome.

RESULTS

In participants with metabolic syndrome, at 4 years of follow-up, the incidence of newly diagnosed diabetes (fasting glucose >or=126 mg/dl) was 17.1% for chlorthalidone, 16.0% for amlodipine (P = 0.49, chlorthalidone vs. amlodipine) and 12.6% for lisinopril (P < 0.05, lisinopril vs. chlorthalidone). For those without metabolic syndrome, the rate of newly diagnosed diabetes was 7.7% for chlorthalidone, 4.2% for amlodipine, and 4.7% for lisinopril (P < 0.05 for both comparisons). There were no differences in relative risks (RRs) for outcomes with amlodipine compared with chlorthalidone in those with metabolic syndrome; in those without metabolic syndrome, there was a higher risk for heart failure (RR 1.55 [95% CI 1.25-1.35]). In comparison with lisinopril, chlorthalidone was superior in those with metabolic syndrome with respect to heart failure (1.31 [1.04-1.64]) and combined cardiovascular disease (CVD) (1.19 [1.07-1.32]). No significant treatment group-metabolic syndrome interaction was noted.

CONCLUSIONS

Despite a less favorable metabolic profile, thiazide-like diuretic initial therapy for hypertension offers similar, and in some instances possibly superior, CVD outcomes in older hypertensive adults with metabolic syndrome, as compared with treatment with CCBs and ACE inhibitors.

Pathogenesis, risk assessment and prevention of type 2 diabetes mellitus

Type 2 diabetes mellitus is a complex, polygenic disease with a heterogeneous pathophysiology, mainly characterised by obesity-associated insulin resistance and a progressive failure of pancreatic beta-cells. Predominant risk factors for its development are abdominal obesity and age; other factors that augment the individual disease risk independent of obesity are the nutritional pattern (low consumption of fibres, high consumption of red meat, saturated and trans fat), lifestyle (smoking, low physical activity), and biomarkers such as blood pressure, HbA1c, serum adiponectin and inflammatory cytokines. These variables can provide the basis for a precise risk assessment and a personalised prevention. Genotyping for the presently known gene variants conferring an increased disease risk adds relatively little to the information provided by the phenotypic risk factors and biomarkers. However, genetic information is necessary for a personalised risk assessment and intervention that begins before phenotypic risk factors are detectable. The incidence of type 2 diabetes can significantly be lowered by reduction of the intraabdominal fat mass (by nutritional intervention and exercise), and by pharmacological control of post-prandial blood glucose excursions. Because of the high portion of non-responders to a preventive intervention, current efforts aim at the identification of phenotypic and genetic variables predicting the success of the intervention.

Insulin resistance, inflammatory biomarkers, and adipokines in patients with chronic kidney disease: effects of angiotensin II blockade

Patients with chronic kidney disease (CKD) present a high prevalence of insulin resistance (IR). Some studies suggest that angiotensin II may influence some cellular pathways that contribute to the pathogenesis of IR and stimulate the release of proinflammatory cytokines. Fifty-two patients who had stages 3 and 4 CKD and no diabetes were administered an angiotensin receptor blocker (ARB), olmesartan (40 mg), for 16 wk. Before and after ARB treatment, metabolic and inflammatory parameters and adipokines were measured. IR was calculated by Homeostasis Model Assessment (HOMA) index. Baseline data were compared with data that were obtained from 25 healthy control individuals of similar age and normal renal function. Compared with control subjects, patients with CKD presented significantly higher BP and waist circumference, higher triglycerides and lower HDL levels, higher insulin levels, and higher mean HOMA index (6.0 +/- 2.7 versus 2.9 +/- 2.2 muU/ml x mmol/L; P < 0.001). In addition, patients with CKD had increased levels of high-sensitivity C-reactive protein, TNF-alpha, and IL-6. In patients with CKD, leptin was positively correlated to abdominal obesity, insulin levels, and IL-6, and adiponectin was inversely correlated to abdominal obesity and insulin levels. Olmesartan treatment resulted in a significant decrease of BP, urinary protein excretion, plasma glucose (99 +/- 16 versus 92 +/- 14 mg/dl; P < 0.05), insulin (23.1 +/- 8.8 versus 19.9 +/- 9; P < 0.05), HOMA index (6.0 +/- 2.7 versus 4.7 +/- 2.8; P < 0.05), and glycated hemoglobin (5.33 +/- 0.58 versus 4.85 +/- 0.81%; P < 0.01). At the same time, there was a significant reduction of high-sensitivity C-reactive protein levels, from 4.45 mg/L (2.45 to 9.00) to 3.55 mg/L (1.80 to 5.40; P < 0.05) and fibrinogen (412 +/- 100 versus 370 +/- 105 mg/dl; P < 0.05). There were no significant differences in adipokine levels after olmesartan treatment. These data demonstrate that patients with CKD have a high prevalence of IR, metabolic syndrome, and chronic inflammation and that the administration of the ARB olmesartan improves IR and inflammation markers in these patients. Plasma adipokine levels that are related to several metabolic risk factors in patients with CKD were not modified by ARB therapy.

Impact of renin-angiotensin-aldosterone system genes on the treatment response of patients with hypertension and metabolic syndrome

OBJECTIVE

To evaluate the influence of clinical, biochemical and genetic markers on the response to antihypertensive treatment in patients with essential hypertension and the metabolic syndrome (MetS).

METHODS

Measurements of anthropometric indices, blood pressure (BP), and metabolic parameters were obtained from the medical records of 132 (77 women) newly diagnosed, untreated hypertensive patients. Renin-angiotensin-aldosterone system (RAAS) genes polymorphisms (including ACE I/D, angiotensinogen M235T, angiotensin II type 1 receptor [AT1-receptor] A1166C) were determined. Response to treatment was defined as BP less than 140/90 mmHg.

RESULTS

Patients with MetS (n=60) had higher systolic BP and pulse pressure and a more atherogenic lipid profile than patients without MetS. The frequencies of the ACE and the AT1-receptor gene polymorphisms were similar between patients with and without MetS. Response to treatment was positively associated with pulse pressure, and the presence of the C allele as well as the AC genotype of the AT1-receptor gene and inversely with age after adjustment for confounding factors.

CONCLUSIONS

RAAS genes distribution does not differ between hypertensive patients with and without the MetS. Higher baseline pulse pressure levels, the presence of the C allele and/or the AC genotype may be in favour of a better response to structured antihypertensive treatment in patients with MetS. However, these findings need to be evaluated in future studies.

Renal mitochondrial impairment is attenuated by AT1 blockade in experimental Type I diabetes

To investigate whether ANG II type 1 (AT(1)) receptor blockade could protect kidney mitochondria in streptozotocin-induced Type 1 diabetes, we treated 8-wk-old male Sprague-Dawley rats with a single streptozotocin injection (65 mg/kg ip; STZ group), streptozotocin and drinking water containing either losartan (30 mg.kg(-1).day(-1); STZ+Los group) or amlodipine (3 mg.kg(-1).day(-1); STZ+Amlo group), or saline (intraperitoneally) and pure water (control group). Four-month-long losartan or amlodipine treatments started 30 days before streptozotocin injection to improve the antioxidant defenses. The number of renal lesions, plasma glucose and lipid levels, and proteinuria were higher and creatinine clearance was lower in STZ and STZ+Amlo compared with STZ+Los and control groups. Glycemia was higher in STZ+Los compared with control. Blood pressure, basal mitochondrial membrane potential and mitochondrial pyruvate content, and renal oxidized glutathione levels were higher and NADH/cytochrome c oxidoreductase activity was lower in STZ compared with the other groups. In STZ and STZ+Amlo groups, mitochondrial H(2)O(2) production rate was higher and uncoupling protein-2 content, cytochrome c oxidase activity, and renal glutathione level were lower than in STZ+Los and control groups. Mitochondrial nitric oxide synthase activity was higher in STZ+Amlo compared with the other groups. Mitochondrial pyruvate content and H(2)O(2) production rate negatively contributed to electron transfer capacity and positively contributed to renal lesions. Uncoupling protein-2 content negatively contributed to mitochondrial H(2)O(2) production rate and renal lesions. Renal glutathione reduction potential positively contributed to mitochondria electron transfer capacity. In conclusion, AT(1) blockade protects kidney mitochondria and kidney structure in streptozotocin-induced diabetes independently of blood pressure and glycemia.

Interactions between microvascular and macrovascular disease in diabetes: pathophysiology and therapeutic implications

Convention partitions the complications of diabetes into two main subtypes. First are the diabetes-specific microvascular complications of retinopathy, nephropathy and neuropathy; second are the atherothrombotic macrovascular complications that account for the majority of premature deaths. Pathological interactions between microvascular and macrovascular complications, for example, nephropathy and macrovascular disease, are common. Similar mechanisms and shared risk factors drive the development and progression of both small and large vessel disease. This concept has therapeutic implications. Mounting evidence points to the need for multifactorial strategies to prevent vascular complications in subjects with diabetes and/or the metabolic syndrome. We advocate a combined therapeutic approach that addresses small and large vessel disease. Preferential use should be made of drug regimens that (i) maximize vascular protection, (ii) reduce the risk of iatrogenic vascular damage and (iii) minimize the increasing problem of polypharmacy.

The role of renin-angiotensin system blockade in the management of hypertension associated with the cardiometabolic syndrome

The mounting epidemic of overweight and obesity has made understanding the relationship between excess weight and associated comorbidities more urgent. Obesity is one of the strongest predictors of the development of hypertension and is an independent risk factor for cardiovascular disease, renal disease, and diabetes mellitus. The concomitant presence of obesity and hypertension, as commonly occurs in the cardiometabolic syndrome, magnifies the risk for cardiovascular and renal disease. The term "obesity-hypertension" thus serves to underscore the link between these two deleterious conditions and to emphasize the imperative for clinical intervention. Adipose tissue is now known to produce hormones and cytokines that promote inflammation, lipid accumulation, and insulin resistance. In addition, adipose tissue contains all the components of the renin-angiotensin system (RAS), which is upregulated in the presence of obesity. Evidence implicates activation of the systemic and adipose tissue RAS, as well as the sympathetic nervous system, as key obesity-related mechanisms of hypertension and other components of the cardiometabolic syndrome. RAS blockade therefore becomes a potential therapeutic strategy in patients with obesity-related hypertension and in persons with the cardiometabolic syndrome. Clinical trials of angiotensin-converting enzyme inhibitors and angiotensin II receptor blockers conducted in predominantly overweight/obese populations have demonstrated significant reductions in cardiovascular and renal disease risk among a range of at-risk patients. RAS blockade also is associated with a reduced risk of new-onset diabetes compared with other classes of antihypertensive therapy. Randomized, controlled trials conducted specifically in patients with obesity and hypertension are needed to determine the optimal therapeutic approach for these patients.

Angiotensin II receptor blockers decreased blood glucose levels: a longitudinal survey using data from electronic medical records

Background

A beneficial effect on glucose metabolism is reported with angiotensin receptor blocker (ARB) treatment of hypertension. The effect on blood glucose level during the course of treatment with ARBs in clinical cases is uncertain. Our objectives were to survey the changes in glucose and HbA1c levels in patients with hypertension over a one-year period, and to study the correlations between these values and the time after the start of ARB therapy.

Methods

We conducted a retrospective longitudinal survey of blood glucose and HbA1c measurements in Japanese patients aged ≥20 years with newly diagnosed hypertension but without diabetes, who had received ARB monotherapy with candesartan cilexetil, losartan potassium, olmesartan medoxomil, telmisartan, or valsartan during the period from December 2004 to November 2005. Data including 2465 measurements of non-fasting blood glucose in 485 patients and 457 measurements of HbA1c in 155 patients were obtained from electronic medical records of Nihon University School of Medicine. Linear mixed effects models were used to analyze the relationship between these longitudinal data of blood examinations and covariates of patient age, sex, medication, and duration of ARB therapy.

Results

Casual blood glucose level was associated with the duration of treatment (P < 0.0001), but not with age, sex, or medication. Blood glucose level was significantly decreased during the periods of 0~3 months (P < 0.0001) and 3~6 months (P = 0.0081) compared with baseline, but was not significantly different between 6~12 months and baseline. There was no association between HbA1c level and covariates of sex, age, medication and duration of treatment.

Conclusion

Our findings provide new clinical evidence that the effects of ARBs on glucose metabolism may change during the course of treatment, suggesting a blood glucose-lowering effect in the short-term after the start of treatment.

Aldosterone and end-organ damage

Aldosterone concentrations are inappropriately high in many patients with hypertension, as well as in an increasing number of individuals with metabolic syndrome and sleep apnoea. A growing body of evidence suggests that aldosterone and/or activation of the MR (mineralocorticoid receptor) contributes to cardiovascular remodelling and renal injury in these conditions. In addition to causing sodium retention and increased blood pressure, MR activation induces oxidative stress, endothelial dysfunction, inflammation and subsequent fibrosis. The MR may be activated by aldosterone and cortisol or via transactivation by the AT(1) (angiotenin II type 1) receptor through a mechanism involving the EGFR (epidermal growth factor receptor) and MAPK (mitogen-activated protein kinase) pathway. In addition, aldosterone can generate rapid non-genomic effects in the heart and vasculature. MR antagonism reduces mortality in patients with CHF (congestive heart failure) and following myocardial infarction. MR antagonism improves endothelial function in patients with CHF, reduces circulating biomarkers of cardiac fibrosis in CHF or following myocardial infarction, reduces blood pressure in resistant hypertension and decreases albuminuria in hypertensive and diabetic patients. In contrast, whereas adrenalectomy improves glucose homoeostasis in hyperaldosteronism, MR antagonism may worsen glucose homoeostasis and impairs endothelial function in diabetes, suggesting a possible detrimental effect of aldosterone via non-genomic pathways.

Pharmacological intervention in prediabetes: considering the risks and benefits

The impact of the diabetes epidemic will be staggering in terms of costs to individuals and society. Social educational initiatives are imperative to altering the lifestyle trends that drive the growth of the epidemic. Targeted lifestyle or drug interventions aimed at preventing progression from prediabetes to type 2 diabetes mellitus carry costs and risks that need to be considered in the context of expected benefits, which also need to be carefully defined. In terms of pharmacological intervention as part of a primary prevention programme, the risk/benefit assessment must include the potential for adverse effects in a large population of asymptomatic individuals, a significant proportion of whom would not progress to diabetes in the absence of treatment and in whom impaired glucose regulation may reflect different underlying pathogenetic mechanisms. Improving the balance of risks and benefits in drug interventions will require a greater ability to determine which treatments are likely to safely improve glucose regulation and prevent diabetes and its adverse cardiovascular outcomes in individual patients.

The role of angiotensin II type 1 receptor blockers in the prevention and management of diabetes mellitus

Angiotensin II Receptor blockers (ARBs) are an important addition to the current range of medications available for treating a wide spectrum of diseases including cardiovascular diseases. Coronary heart disease (CHD) is the most common cause of death in the United Kingdom and worldwide. More importantly, the presence of the metabolic syndrome and the likelihood of diabetes mellitus taking on epidemic proportions in the years to come all threaten to maintain the mortality rate due to CHD. This review article focuses on the clinical studies that have helped define the trends in the usage of these agents in the prevention and treatment of diabetes mellitus and its complications and also explores possible mechanisms of action and future developments.

Approaches to prevention of cardiovascular complications and events in diabetes mellitus

Diabetes mellitus affects about 8% of the adult population. The estimated number of patients with diabetes, presently about 170 million people, is expected to increase by 50-70% within the next 25 years. Diabetes is an important component of the complex of 'common' cardiovascular risk factors, and is responsible for acceleration and worsening of atherothrombosis. Major cardiovascular events cause about 80% of the total mortality in diabetic patients. Diabetes also induces peculiar microangiopathic changes leading to diabetic nephropathy conducive to end-stage renal failure, and to diabetic retinopathy that may progress to vision loss and blindness. In terms of major cardiovascular events, coronary heart disease and ischaemic stroke are the main causes of morbidity and mortality in diabetic patients. Peripheral arterial disease frequently occurs, and is more likely to be conducive to critical limb ischaemia and amputation than in the absence of diabetes. Although there are a number of differences in the pathogenesis and clinical features of diabetic macroangiopathy and microangiopathy, these two entities often coexist and induce mutually worsening effects. Endothelial injury, dysfunction and damage are common starting points for both conditions. Causes of endothelial injury can be distinguished into those 'common' to nondiabetic atherothrombosis, such as hypertension, dyslipidaemia, smoking, hypercoagulability and platelet activation; and those more specific and in some cases 'unique' to diabetes and directly related to the metabolic derangement of the disease, such as (i) desulfation of glycosaminoglycans (GAGs) of the vascular matrix; (ii) formation of advanced glycation end-products (AGE) and their endothelial receptors (RAGE); (iii) oxidative and reductive stress; (iv) decline in nitric oxide production; (v) activation of the renin-angiotensin aldosterone system (RAAS); and (vi) endothelial inflammation caused by glucose, insulin, insulin precursors and AGE/RAGE. Prevention of major cardiovascular events with the antithrombotic agent aspirin (acetylsalicylic acid) is widely recommended, but reportedly underutilised in patients with diabetes. However, some data suggest that aspirin may be less effective than expected in preventing cardiovascular events and especially mortality in patients with diabetes, as well as in slowing progression of retinopathy. In contrast, a recent study found picotamide, a direct thromboxane inhibitor, to be superior to aspirin in diabetic patients. Clopidogrel was either equivalent or less active in diabetic versus nondiabetic patients, depending upon different clinical settings.Recent studies have shown that some GAG compounds are able to reduce micro- and macroalbuminuria in diabetic nephropathy, and hard exudates in diabetic retinopathy, but it is as yet unknown whether these agents also influence the natural history of microvascular complications of diabetes. Lifestyle changes and physical exercise are also essential in preventing cardiovascular events in diabetic patients. Available data on the control of the metabolic state and the main risk factors show that careful adjustment of blood sugar and glycated haemoglobin is more effective in counteracting microvascular damage than in preventing major cardiovascular events. The latter objective requires a more comprehensive approach to the whole constellation of risk factors both specific for diabetes and common to atherothrombosis. This approach includes lifestyle modifications, such as dietary changes and smoking cessation and the use of HMG-CoA reductase inhibitors (statins), which are able to correct the lipid status and to prevent major cardiovascular events independently of the baseline lipidaemic or cardiovascular status. Tight control of hypertension is essential to reduce not only major cardiovascular events but also microvascular complications. Among antihypertensive measures, blockade of the RAAS by means of ACE inhibitors or angiotensin II receptor antagonists recently emerged as a potentially polyvalent approach, not only for treating hypertension and reducing cardiovascular events, but also to prevent or reduce albuminuria, counteract diabetic nephropathy and lower the occurrence of new type 2 diabetes in individuals at risk.

Prevention of type 2 diabetes: an update

With the rising tide of the diabetes epidemic leading to increased morbidity and mortality (primarily from cardiovascular disease), together with failure to control the disease and its associated complications, prevention of diabetes appears to be the logical option for curbing this epidemic. Several trials have been completed, and others ongoing, using various strategies for diabetes prevention. In this review, we provide an update on diabetes prevention strategies, highlighting the rationale behind such interventions, together with an outlook of the ongoing efforts that are likely to provide additional options for patients at risk for diabetes.

Hypertension and kidney protection in the elderly: what is the evidence in 2007?

Hypertension and diabetes mellitus are the two most widely recognized risk factors for cardiovascular disease (CVD), chronic kidney disease (CKD), and end-stage renal disease (ESRD) requiring dialysis/transplantation; both become increasingly important as one ages. Common pathways and mechanisms are involved in the development of renal vascular lesions in both conditions, and effective treatments for each are now available to reduce morbidity, mortality and progression of organ damage. Although this review will focus primarily on the ability to protect the kidney and vasculature elsewhere by lowering blood pressure in the elderly, other approaches, specifically dietary restriction of protein, strict control of diabetes mellitus, and the management of the different dyslipidemias, must be used in conjunction with the antihypertensive agents to obtain optimum protection.

Renin-angiotensin-system blockade in the prevention of diabetes

Type 2 diabetes often occurs in association with hypertension and cardiovascular disease, and markedly increases cardiovascular risk. Strategies to reduce the incidence of diabetes in patients with cardiovascular disease or at high risk for such disease are therefore important. Certain classes of antihypertensive agents, namely the thiazide diuretics and beta-blockers, have an adverse impact on the metabolic profile and increase the risk for new-onset diabetes in hypertensive subjects. In contrast, angiotensin-converting enzyme (ACE) inhibitors and angiotensin receptor blockers (ARBs), which are blockers of the renin-angiotensin system (RAS), have been shown to increase insulin sensitivity. They may also reduce the risk of diabetes in patients with hypertension or cardiovascular disorders. Some of the evidence in favour of ACE inhibitors and ARBs has come from studies with active comparators that have potential adverse metabolic effects. However, the Candesartan in Heart failure-Assessment of Reduction in Mortality and morbidity (CHARM) programme demonstrated that the ARB candesartan reduced the incidence of diabetes in heart failure patients in comparison to placebo. The mechanisms responsible for the beneficial effects of RAS blockade remain to be established. Nevertheless, a treatment that can control hypertension and reduce the risk of onset of type 2 diabetes at the same time is certainly desirable.

Antihypertensive medications and risk of diabetes mellitus

PURPOSE OF REVIEW

Over the past decade post-hoc analyses of clinical trials and observational studies have tended to show that participants treated with thiazide diuretics are at greater risk for newly diagnosed diabetes mellitus than those treated with other medication classes. We review the results of several recent studies on the impact of thiazide-related hyperglycemia and diabetes mellitus on cardiovascular disease outcomes. We also examine the impact of the glucose-sparing effects of angiotensin-converting enzyme inhibitors and angiotensin receptor blockers on preventing cardiovascular disease.

RECENT FINDINGS

No consistent or conclusive evidence has been found that hyperglycemia or diabetes mellitus in association with thiazide diuretic use is associated with increased cardiovascular disease outcomes. This benign outcome may be a consequence of the fact that only a segment of such diuretic-associated cases is induced by the usual etiologic mechanisms that are associated with classic 'diabetes mellitus'. Likewise, no evidence has been found that the glucose-lowering effect of angiotensin-converting enzyme inhibitors is associated with decreased cardiovascular disease risk.

SUMMARY

We conclude that thiazide diuretics are safe to use, even in hypertensive individuals at risk for incident glucose disorders. The use of angiotensin-converting enzyme inhibitors for protection against glucose disorders and subsequent cardiovascular disease remains to be determined.

Treating insulin resistance: future prospects

Insulin resistance typically reflects multiple defects of insulin receptor and post-receptor signalling that impair a diverse range of metabolic and vascular actions. Many potential intervention targets and compounds with therapeutic activity have been described. Proof of principle for a non-peptide insulin mimetic has been demonstrated by specific activation of the intracellular B-subunit of the insulin receptor. Potentiation of insulin action has been achieved with agents that enhance phosphorylation and prolong the tyrosine kinase activity of the insulin receptor and its protein substrates after activation by insulin. These include inhibitors of phosphatases and serine kinases that normally prevent or terminate tyrosine kinase signalling. Additional approaches involve increasing the activity of phosphatidylinositol 3-kinase and other downstream components of the insulin signalling pathways. Experimental interventions to remove signalling defects caused by cytokines, certain adipocyte hormones, excess fatty acids, glucotoxicity and negative feedback by distal signalling steps have also indicated therapeutic possibilities. Several hormones, metabolic enzymes, minerals, co-factors and transcription co-activators have shown insulin-sensitising potential. Since insulin resistance affects many metabolic and cardiovascular diseases, it provides an opportunity for simultaneous therapeutic attack on a broad front.

[Insulin and angiotensin II signaling pathways cross-talk: implications with the association between diabetes mellitus, arterial hypertension and cardiovascular disease]

Insulin (Ins) and angiotensin II (AII) play pivotal roles in the control of two vital and closely related systems: the metabolic and the circulatory, respectively. A failure in the proper action of each of these hormones results, to a variable degree, in the development of two highly prevalent and commonly overlapping diseases--diabetes mellitus (DM) and hypertension (AH). In recent years, a series of studies has revealed a tight connection between the signal transduction pathways that mediate Ins and AII actions in target tissues. This molecular cross-talk occurs at multiple levels and plays an important role in phenomena that range from the action of anti-hypertensive drugs to cardiac hypertrophy and energy acquisition by the heart. At the extracellular level, the angiotensin-converting enzyme controls AII synthesis but also interferes with Ins signaling through the proper regulation of AII and the accumulation of bradykinin. At an early intracellular level, AII, acting through JAK-2/IRS-1/PI3-kinase, JNK and ERK, may induce the serine phosphorylation and inhibition of key elements of the Ins-signaling pathway. Finally, by inducing the expression of the regulatory protein SOCS-3, AII may impose a late control on the Ins signal. This review will focus on the main advances obtained in this field and will discuss the implications of this molecular cross-talk in the common clinical association between DM and AH.

Potential mechanisms of stroke benefit favoring losartan in the Losartan Intervention For Endpoint reduction in hypertension (LIFE) study

INTRODUCTION

The Losartan Intervention For Endpoint reduction in hypertension (LIFE) study is the first, and, so far, the only endpoint trial in patients with hypertension and left ventricular hypertrophy (LVH) to show a divergent therapeutic outcome of one treatment modality over another with equivalent blood pressure control. The purpose of this article is to review post hoc sub-analyses of LIFE study data and other clinical studies that offer some insight into possible treatment-related differences contributing to the superior stroke outcome of losartan versus atenolol beyond blood pressure reduction.

METHODS

Relevant randomized clinical trials and review articles were identified through a MEDLINE search of English-language articles published between 1990 and 2006 using the search terms losartan, atenolol, LIFE, hypertension, and LVH. Articles describing major clinical studies, new data, or mechanisms pertinent to the LIFE study were selected for review.

RESULTS

Differences in blood pressure or in the distribution of add-on medications were not evident between study groups in the LIFE study. Thus, the observed outcomes benefits favoring losartan may involve other possible mechanisms, including differential effects of losartan and atenolol on LVH regression, left atrial diameter, atrial fibrillation, brain natriuretic peptide, vascular structure, thrombus formation/platelet aggregation, serum uric acid, albuminuria, new-onset diabetes, and lipid metabolism. Alternative explanations for the LIFE study findings have also been put forward, including the choice of atenolol as an appropriate active comparator and differential effects between treatment groups on central pulse pressure. Additional clinical trials are needed to determine if the beneficial effects of losartan seen in LIFE are shared by other inhibitors of the renin-angiotensin system.

CONCLUSION

Sub-analyses of the LIFE study data suggest that losartan's stroke benefit may arise from a mosaic of mechanisms rather than a single action. Further studies are expected to continue to delineate the mechanisms of differential responses to treatments in LIFE.

Is prevention of Type-2 diabetes feasible and efficient in primary care? A systematic PubMed review

AIM

To answer: (1) Do we have effective treatments to improve prognosis for those identified at risk of Type-2 diabetes? (2) Will prevention be cost-effective?

METHODS

A systematic search was done in PubMed using the following search strategy: "diabetes AND prevention AND (IFG OR IGT)". Restrictions were: "English, Meta-Analysis, Randomized Controlled Trial, Review, Humans".

RESULTS

Few randomised controlled preventive trials were found. Almost all were done in research settings in people with high risk of developing Type-2 diabetes. It seems possible to either delay or prevent Type-2 diabetes through lifestyle interventions and medication. Cost-utility analyses are few in number and come to very different conclusions as to whether health policy should promote prevention of Type-2 diabetes.

CONCLUSION

Intervention studies using lifestyle counselling and drug therapy in research settings illustrate promising results with lowering of the incidence of Type-2 diabetes, meaning that Type-2 diabetes can be delayed or prevented. It is, however, questionable whether these interventions are cost-effective. We need studies in routine clinical settings evaluating morbidity, mortality and cost-effectiveness as primary outcomes. While waiting for these studies to prove cost-effective, patients with pre-diabetes should be treated according to their 10-year risk of cardiovascular disease following present guidelines.

The renin-angiotensin system and insulin resistance

Insulin resistance upregulates the renin-angiotensin system (RAS), which contributes to the pathogenesis of hypertension, heart failure, and atherosclerosis. RAS inhibition decreases cardiovascular and renal morbidity and mortality and the incidence of new-onset type 2 diabetes. To the same degree, angiotensin II impairs insulin signaling, induces inflammation via the nuclear factor-kappaB pathway, and reduces nitric oxide availability and facilitates vasoconstriction, leading to insulin resistance and endothelial dysfunction. Thus, the RAS, insulin resistance, and inflammation perpetuate each other and coordinately contribute to endothelial dysfunction, vascular injury, and atherosclerosis.

The role of renin-angiotensin system inhibition in the treatment of hypertension in metabolic syndrome: are all the angiotensin receptor blockers equal?

The metabolic syndrome (MetS) is a strong predictor of cardiovascular morbidity and mortality, as well as new Type 2 diabetes. MetS consists of visceral obesity, elevated blood pressure, impaired glucose metabolism, atherogenic dyslipidaemia (elevated triglycerides and low levels of high-density lipoprotein cholesterol), as well as other metabolic abnormalities. The underlying pathophysiology seems to be largely, but not uniquely, attributable to insulin resistance. Existing antihypertensive drugs were designed to lower blood pressure rather than to modify the metabolic abnormalities associated with hypertension. This review considers the role of renin-angiotensin system inhibition and especially the use of angiotensin receptor blockers (ARBs) in the treatment of hypertension in MetS. There are differences among ARBs. Among them is the uricosuric effect of losartan. Furthermore, telmisartan may function as a partial agonist of the peroxisome proliferator-activated receptor-gamma (PPAR-gamma).

Incident diabetes in clinical trials of antihypertensive drugs: a network meta-analysis

BACKGROUND

The effect of different classes of antihypertensive drugs on incident diabetes mellitus is controversial because traditional meta-analyses are hindered by heterogeneity across trials and the absence of trials comparing angiotensin-converting-enzyme (ACE) inhibitors with angiotensin-receptor blockers (ARB). We therefore undertook a network meta-analysis, which accounts for both direct and indirect comparisons to assess the effects of antihypertensive agents on incident diabetes.

METHODS

We undertook a systematic review up to Sept 15, 2006, and identified 48 randomised groups of 22 clinical trials with 143,153 participants who did not have diabetes at randomisation and so were eligible for inclusion in our analysis. 17 trials enrolled patients with hypertension, three enrolled high-risk patients, and one enrolled those with heart failure. The main outcome was the proportion of patients who developed diabetes.

FINDINGS

Initial drug therapy used in the trials (and the number of patients with diabetes of the total number at risk) included: an ARB (1189 of 14,185, or 8.38%), ACE inhibitor (1618 of 22,941, or 7.05%), calcium-channel blocker (CCB, 2791 of 38,607, or 7.23%), placebo (1686 of 24,767, or 6.81%), beta blocker (2705 of 35,745, or 7.57%), or diuretic (998 of 18,699, or 5.34%). With an initial diuretic as the standard of comparison (eight groups), the degree of incoherence (a measure of how closely the entire network fits together) was small (omega=0.000017, eight degrees of freedom). The odds ratios were: ARB (five groups) 0.57 (95% CI 0.46-0.72, p<0.0001); ACE inhibitor (eight groups) 0.67 (0.56-0.80, p<0.0001); CCB (nine groups): 0.75 (0.62-0.90, p=0.002); placebo (nine groups) 0.77 (0.63-0.94, p = 0.009); beta blocker (nine groups) 0.90 (0.75-1.09, p=0.30). These estimates changed little in many sensitivity analyses.

INTERPRETATION

The association of antihypertensive drugs with incident diabetes is therefore lowest for ARB and ACE inhibitors followed by CCB and placebo, beta blockers and diuretics in rank order.

Effect of angiotensin-converting enzyme inhibitors and angiotensin II type 1 receptor blockers on the rate of new-onset diabetes mellitus: a review and pooled analysis

The rising prevalence and health burden of diabetes mellitus require that new approaches for prevention among high-risk populations be evaluated. Emerging evidence from the prospective evaluations of secondary and tertiary outcomes and from retrospective evaluations in randomized controlled trials suggests that angiotensin-converting enzyme (ACE) inhibitors and angiotensin II type 1 receptor blockers (ARBs) may reduce the occurrence of new-onset diabetes. Therefore, we each independently searched MEDLINE for randomized controlled trials from January 1966-October 2005 that used an ACE inhibitor or ARB as a primary intervention versus a control group not receiving an ACE inhibitor or ARB and that reported the occurrence of diabetes. Thirteen trials were identified. In each of the 13 studies, the frequency of diabetes in the ACE inhibitor or ARB groups was lower than that in the control groups. In addition, it was consistent in that no study significantly excluded any benefit from ACE inhibitors or ARBs on the rate of new-onset diabetes. The combined occurrence of new-onset diabetes in all 13 studies was 2249 cases among 31,283 patients (7.2%) in the ACE inhibitor or ARB group versus 3230 cases among 35,988 patients (9.0%) in the control group. The combined relative risk of diabetes was 0.80, with a 95% confidence interval of 0.76-0.84, based on a two-sided alpha of 0.05, in favor of ACE inhibitors and ARBs. This observation needs to be confirmed by randomized controlled trials with the frequency of diabetes as the primary prospective end point.

Drug-Induced Endocrine and Metabolic Disorders

Complex interactions exist amongst the various components of the neuroendocrine system in order to maintain homeostasis, energy balance and reproductive function. These components include the hypothalamus-pituitary- adrenal and -gonadal axes, the renin-angiotensin-aldosterone system, the sympathetic nervous system and the pancreatic islets. These hormones, peptides and neurotransmitters act in concert to regulate the functions of many organs, notably the liver, muscles, kidneys, thyroid, bone, adrenal glands, adipocytes, vasculature, intestinal tract and gonads, through many intermediary pathways. Endocrine and metabolic disorders can arise from imbalance amongst numerous hormonal factors. These disturbances may be due to endogenous processes, such as increased secretion of hormones from a tumour, as well as exogenous drug administration. Drugs can cause endocrine abnormalities via different mechanisms, including direct alteration of hormone production, changes in the regulation of the hormonal axis, effects on hormonal transport, binding, and signalling, as well as similar changes to counter-regulatory hormone systems. Furthermore, drugs can affect the evaluation of endocrine parameters by causing interference with diagnostic tests. Common drug-induced endocrine and metabolic disorders include disorders of carbohydrate metabolism, electrolyte and calcium abnormalities, as well as drug-induced thyroid and gonadal disorders. An understanding of the proposed mechanisms of these drug effects and their evaluation and differential diagnosis may allow for more critical interpretation of the clinical observations associated with such disorders, better prediction of drug-induced adverse effects and better choices of and rationales for treatment.

The altered homeostatic theory: A hypothesis proposed to be useful in understanding and preventing ischemic heart disease, hypertension, and diabetes – including reducing the risk of age and atherosclerosis

Evidence will be presented to support the usefulness of the altered homeostatic theory in understanding basic pathogenetic mechanisms of ischemic heart disease (IHD), hypertension, and diabetes, and in improving prevention of these disorders. The theory argues that: IHD, hypertension, and diabetes share the same basic pathogenesis; risk factors favor a sympathetic homeostatic shift; preventative factors favor a parasympathetic homeostatic shift; risk and preventative factors oppose each other through a dynamic risk/prevention balance; and prevention should be based on improving the risk/prevention balance. Prevention based on improving the risk/prevention balance should be more effective, as this method is regarded as reflecting more accurately basic pathogenetic mechanisms. As example, the theory argues that the risk of supposedly nonmodifiable risk factors as age and the risk of relatively nonmodifiable atherosclerosis can be reduced significantly. The possible validity of the altered homeostatic theory was tested by a study based on multiple associations. Findings support a common pathogenesis for IHD, hypertension, and diabetes based on a sympathetic homeostatic shift, and the usefulness of prevention based on improving the risk/prevention balance by using standard pharmaceutical and lifestyle preventative measures. The same set of multiple and diverse risk factors favored IHD, hypertension, and diabetes, and the same set of multiple and diverse pharmaceutical and lifestyle preventative measures prevented these disorders. Also, the same set of preventative agents generally improved cognitive function and bone density, and reduced the incidence of Alzheimer's disease, atrial fibrillation, and cancer. Unexpectedly, evidence was developed that four major attributes of sympathetic activation represent four major risk factors; attributes of sympathetic activation are a tendency toward thrombosis and vasoconstriction, lipidemia, inflammation, and hyperglycemia, and corresponding risk factors are endothelial dysfunction (which expresses thrombosis/vasoconstriction and epitomizes this tendency), dyslipidemia, inflammation, and insulin resistance. These findings, plus other information, provide evidence that dyslipidemia acts mainly as a marker of risk of IHD, rather than being the basic mechanism of this disorder. However, prevention generally is based solely on improvement of dyslipidemia; basing prevention on dyslipidemia relatively underemphasizes the importance of other significant risk factors and, by certifying its validity, discourages alternate pathogenetic approaches. Also, development of myocardial infarction is approached differently. It seems generally accepted that dyslipidemia results rather automatically in infarction through the sequence of atherosclerosis, atherosclerotic complications, and thrombosis. In contrast, distinction is made between development of atherosclerosis and acute induction of infarction--where atherosclerosis is only one of multiple risk factors.