Diabetes und Hypertonie

Background

Diabetes mellitus is a disease which leads to vascular damage resulting in subsequent severe cardiovascular complications, such as myocardial infarction and stroke. This process is aggravated by coexisting hypertension.

Objective

This analysis gives a review of the latest study results on prognosis, blood pressure targets, drug therapy and interventional therapy in patients with diabetes and hypertension. Selected studies published in recent years with practical relevance for patients with diabetes and hypertension are presented.

Summary

Patients with simultaneous diabetes and hypertension have a poorer prognosis and a higher cardiovascular risk compared to patients with diabetes but without hypertension. Patients with diabetes and hypertension benefit from interventional blood pressure therapy

     

Hypertonie beim Diabetes mellitus

Zusammenfassung Die arterielle Hypertonie tritt sowohl bei Typ-1- als auch bei Typ-2-Diabetikern gehäuft auf. Sie ist ein wichtiger Risikofaktor für Erkrankungen des Herzens und des zerebralen Gefäßsystems sowie für die Entstehung einer chronischen Niereninsuffizienz und peripherer Durchblutungsstörungen. Die Wahrscheinlichkeit für kardiovaskuläre Komplikationen steigt mit der Höhe des arteriellen Blutdrucks kontinuierlich und exponentiell an. Bei Diabetikern ist das Risiko für kardiovaskuläre Erkrankungen und mikrovaskuläre Komplikationen zusätzlich erhöht, wenn gleichzeitig eine arterielle Hypertonie vorliegt. Neben Allgemeinmaßnahmen wie Gewichtsreduktion bei Übergewicht ist meist eine medikamentöse antihypertensive Therapie erforderlich (Zielblutdruck <130/80 mmHg, bei Nephropathie <120 mmHg systolisch). Die Wahl des Antihypertensivums (ACE-Hemmer, AT1-Rezeptor-Blocker, kardioselektive -Blocker, Kalziumantagonisten, Diuretika) richtet sich nach Begleiterkrankungen und Kontraindikationen. Reicht eine Monotherapie nicht aus, ist eine Kombinationstherapie indiziert. Bei Diabetes mellitus ist neben der optimierten Einstellung des Blutzuckers eine gute Blutdruckbehandlung für die Vermeidung von diabetischen Komplikationen und damit die Verbesserung der Lebensqualität und die Verlängerung des Lebens von entscheidender Bedeutung.     

Hypertonie und Bewegung

Physical exercise is of paramount therapeutic importance in nonpharmacological interventions of arterial hypertension. The extent and the effects of exercise on blood pressure lowering are analyzed according to the actual literature. Suitable and nonsuitable activities are considered. Dynamic isotonic endurance training is more effective than static isometric exercise. A rather low or moderate extent of endurance training lowers the systolic and diastolic blood pressure by approximately 5-11 mmHg and 3-8 mmHg, respectively. This effect of exercise can be achieved besides the favorable effects on other cardiovascular risk factors. Intensity of exercise should be monitored by the heart rate. The mean intensity should not exceed 70% of the maximal heart rate. An initial ergometry might be suitable for the planning of training recommendations.     

Demenz und Hypertonie

Due to the demographic situation, dementia is becoming an important public health problem of increasing magnitude. Because of an aging population worldwide, the incidence of dementia is expected to rise exponentially over the coming decades. Attempts to find a causal therapy when manifest dementia is diagnosed have so far failed. At present, available therapies provide only minor and temporary relief. Diagnosis and sufficient control of risk factors for dementia must be the main goals. Epidemiological studies have identified hypertension as a main risk factor for dementia, particularly vascular dementia, as well as for Alzheimer’s disease. Hypertension in midlife is particularly associated with an increased risk of developing cognitive impairment and dementia. These findings provide a therapeutic opportunity to intervene and prevent dementia. Several clinical trials have shown the protective effect of antihypertensive therapy with additional benefits from substances that block the renin–angiotensin system.     

Niere und Hypertonie

The regulation of blood pressure is a complex process, involving several organs. The kidney plays a major role and is involved in the initiation and maintenance of hypertension. Mechanisms involved are: (1) the sympathetic nerveous system, (2) the renin-angiotensin system, (3) the regulation of sodium and water balance, (4) the production of vasoactive substances such as endothelin, adenosine or nitric oxide (NO), and (5) structural alterations such as a reduced number of glomeruli and nephrons.Several therapeutic intervention strategies affecting these mechanisms have already proven to be effective antihypertensive drugs.     

Schlaganfall und Hypertonie

Arterial hypertension is the most important risk factor for stroke. Many interventional trials have unambiguously proven the benefit of antihypertensive therapy in both primary and secondary prevention for all age categories. No recommendation for any single antihypertensive substance for the primary prevention of stroke exists. Achieving the therapeutic goal (normotension) is the crucial factor. In most patients, multiple combinations of antihypertensive drugs are required to do this. For high-risk patients and in secondary prevention, substances inhibiting the renin-angiotensin-system, especially combined with calcium antagonists and indapamid, may be advantageous, while beta-blockers appear to be less well suited. In patients suffering from left-ventricular hypertrophy or atrial fibrillation, sartanes are the best-documented drug class. As TIA or stroke will often disturb the normal circadian rhythm of blood pressure and eliminate the usual night-time drop, monitoring of the therapeutic results must include ambulatory 24h measurements. The interrelation between vascular dementia and hypertension is by now also considered proven. An early start of antihypertensive treatment can prevent the development of dementia and impaired cognitive function.     

Salz und Hypertonie

The reduction in salt intake is an important principle in non-pharmacological treatment of hypertension. However, it is difficult to maintain a low salt diet over a long time period due to the high salt content in general nutrition and compliance deficits. Recommendations to lower salt intake have been challenged repeatedly. The pathomechanistic basis of the blood pressure increasing effect of high salt intake has been well demonstrated and investigated in detail. The blood pressure lowering effect of a low salt diet has been proven as well. However, proof of a positive effect of a low salt diet on cardiovascular outcome is still under debate, especially as studies to investigate this aspect are generally hampered by the difficulties to perform studies with lowering salt intake in a controlled randomized form over a long time period. However, more studies of good quality are available demonstrating the favorable effect of low salt diets on cardiovascular outcome. Reduction in salt intake to below 6?g per day is recommended by guidelines on hypertension throughout the world.     

Salzregulation und Hypertonie

Background

Textbook theory holds that extracellular bodily fluids readily equilibrate, electrolyte concentrations in the compartments are constant, and the kidneys are solely responsible for controlling body sodium content. Recent findings have questioned these hypotheses.

Objectives

Are relevant amounts of Na⁺ stored in the body and regulated by extrarenal mechanisms, and what is the relationship to arterial hypertension?

Methods

Discussion of basic and clinical research findings.

Results

Recent findings from chemical analysis studies in laboratory animals as well as noninvasive quantitative Na⁺ magnetic resonance imaging (Na-MRI) studies in patients have shown that remarkable amounts of Na⁺ are stored in muscle and in skin without commensurate water retention. Furthermore, an ultra-long Na⁺ balance study in humans suggests the presence of endogenous clocks that generate weekly and monthly infradian rhythmicity of Na⁺ storage independent of salt intake. Animal experiments suggest that fluids in the skin interstitium are hypertonic compared with plasma, and that interstitial osmotic stress induces local extrarenal immune cell and lymph capillary-driven mechanisms for electrolyte clearance and maintenance of the internal environment that is of relevance for systemic blood pressure control.

Conclusion

Unexpected findings have transformed current thinking on sodium balance, drawn attention to the importance of immune cell-driven “kidney-like” lymphatic clearance of interstitial fluid in regulating the“milieu intérieur” and permit a new non-invasive technique for clinical investigation. This could have a profound relevance to the global burden of cardiovascular disease.     

Glukokortikoide und Hypertonie

Severe arterial hypertension is a hallmark of Cushing syndrome which occurs in 80% of the patients. Additionally, persistent cortisol excess induces obesity, hyperinsulinemia with disturbed glucose tolerance and dyslipidemia which all contribute to the development of hypertension and its deleterious sequelae. Cortisol effects are mediated through diversely distributed intracellular glucocorticoid and mineralocorticoid receptors which are protected by the 11-β-hydroxysteroiddehydrogenase type 2 in cells of some organs (i.e. kidney) but not in other. A highly complex clinical picture evolves in case of hypercortisolism due to the ubiquitous distribution of steroid receptors with different affinity and binding capacities for glucocorticoids. The present review focuses on the cortisol induced changes in blood pressure regulation which contribute to the development of hypertension.     

Adipositas und Hypertonie

Zum Thema Die Insulinresistenz mit konsekutiver Hyperinsulin?mie ist ein Schlüsselph?nomen für die überzuf?llig h?ufig assoziierte Manifestation koronarer Risikofaktoren, inklusive der Adipositas and arteriellen Hypertonie. Im Gegensatz z.B. zur Dyslipoprotein?mie und Glukoseintoleranz ist eine kausale Beziehung zwischen der Insulinresistenz und arteriellen Hypertonie noch nicht direkt gezeigt. Bei dieser Beziehung scheint für die klinische Auspr?gung der arteriellen Hypertonie eine begleitende Adipositas von gro?er Bedeutung zu sein. M?gliche pathophysiologische Mechanismen, wie z.B. erh?hte Sympathikus-Aktivierung, Freisetzung humoraler Faktoren aus dem Fettgewebe und die viszerale Fettverteilung werden diskutiert.     

Frauen und Hypertonie

Zusammenfassung Die arterielle Hypertonie ist einer der bedeutendsten Risikofaktoren für die hohe kardiovaskuläre Mortalität und Morbidität in westlichen industrialisierten Ländern. In Deutschland leiden mehr Frauen als Männer an einer arteriellen Hypertonie, und mehr Frauen als Männer sterben an kardiovaskulären Erkrankungen. Während prämenopausal das kardiovaskuläre Risiko von Frauen im Vergleich zu Männern geringer ist, kehrt sich dies nach Einsetzen der Menopause um. Es wird angenommen, dass endogene Östrogene jüngere Frauen vor kardiovaskulären Erkrankungen schützen. In die frühen Hypertoniestudien wurden keine Frauen eingeschlossen, und anfangs glaubte man, dass Frauen von einer antihypertensiven Therapie nicht profitieren. Inzwischen hat sich jedoch der Nutzen einer adäquaten Blutdrucksenkung sowohl für Männer als auch für Frauen gezeigt. Die Effekte der Therapie sind bei älteren Frauen größer als bei jüngeren. Insgesamt werden heute mehr Frauen als Männer antihypertensiv behandelt, und es gibt auch Hinweise auf eine höhere Therapietreue bei Frauen. Allgemeinmaßnahmen als Mittel zur Blutdrucksenkung führen bei Frauen seltener zum Erfolg. Bisher liegen nur wenige Daten zu möglichen geschlechtsspezifischen Unterschieden in der Effektivität der einzelnen Antihypertensiva–Klassen und deren Nebenwirkungen vor. Elektrolytstörungen als Folge einer Therapie mit Thiaziddiuretika oder Husten unter ACE–Hemmern werden bei Frauen häufiger beobachtet. Neue Daten aus dem Beobachtungsarm der Women’s Health Initiative Observational Study zeigen ein erhöhtes kardiovaskuläres Risiko für Frauen unter einer Monotherapie mit Calciumantagonisten sowie unter einer Kombination von Calciumantagonisten und Diuretika. Zurzeit sind unabhängig vom Geschlecht die meisten Hypertoniker in Deutschland nicht ausreichend behandelt. Diese Situation gilt es zu bessern. Dabei müssen weitere Studien zeigen, ob eine geschlechtsspezifische Differenzierung der Therapie erfolgen sollte.     

Niere und Hypertonie

In patients with chronic kidney disease elevated blood pressure is a common finding, but primary hypertension can also damage healthy kidneys. Renal outcome is strictly dependent on blood pressure, no matter whether the kidneys are cause or consequence of hypertension. Furthermore, hypertension and kidney disease are strong cardiovascular risk factors. In every patient diagnosed with hypertension glomerular filtration rate has to be checked. Proteinuria and structural abnormalities of the kidneys should be ruled out. Patients with a decreased glomerular filtration rate, proteinuria or pathologic ultrasound should be seen by a nephrologist. A strict antihypertensive therapy (blood pressure <130/80 mmHg) can substantially improve the prognosis of hypertensive renal patients. In patients with kidney damage, inhibitors of the renin-angiotensin-system are preferred. To avoid adverse events a close monitoring of antihypertensive therapy is warranted.     

Renale Denervierung und Hypertonie

Catheter-based renal nerve ablation can lower blood pressure (BP) in hypertensive patients. The concept is based on solid physiological studies suggesting that efferent and afferent renal nerves contribute to arterial hypertension. The preliminary results on the efficacy and safety of catheter-based renal nerve ablation on BP control in resistant hypertension have been encouraging; however, these studies were uncontrolled. In several small studies it was observed early that most patients can be controlled by pharmaceutical treatment and only a few patients respond to ablation therapy. A large prospective trial with a control group (sham treatment) was therefore necessary. The Simplicity-3 trial fulfilled these criteria. More than 600 patients were successfully studied and in March 2014 the results were published. No significant differences between the two groups were observed, one treated with renal nerve ablation and the other group controlled only by medication. These results are in contrast to the previous (uncontrolled) studies and observations from a worldwide registry. Several explanations have been put forward to explain these results. Important are (1) compliance, i.e. patients taking their medication during the study and also (2) inexperience with the method in small centers. Simplicity-3 has put a halt on using renal denervation in most countries. It is now important to find out why the method only works in some patients, what the criteria to use it are and to define a patient group where renal denervation is useful as a therapeutic method to treat patients with hypertension.     

Thrombembolien und pulmonale Hypertonie

Chronic thrombembolic pulmonary hypertension (CTEPH) represents a common type of pulmonary hypertension and is associated with significant morbidity and mortality. The prognosis of this condition reflects the degree of associated right ventricular dysfunction. Unresolved thrombemboli and possible in situ thrombosis lead to obstruction of pulmonary arteries resulting in elevated pressures in those areas of the vasculature that were spared from thromboembolic occlusion. This can resemble pathomechanisms in patients with pulmonary arterial hypertension. However the understanding of pulmonary vascular remodeling in patients with CTEPH is incomplete. Pulmonary endarterectomy of the obstructing thromboembolic material should be performed in patients who are accessible to surgery. In patients who are judged inoperable or with persistent pulmonary hypertension treatment with pulmonary arterial hypertension medications can be considered. This could contribute to improved clinical outcome and survival, whereas further controlled studies are required addressing this question.     

Arterielle Hypertonie und Herzinsuffizienz

Zum Thema Die Hypertonie, h?ufig mit Diabetes, Fettstoffwechselst?rung und Adipositas verbunden, ist die wesentliche Ursache der koronaren Herzkrankheit (KHK). Wenn man einerseits die hohe Pr?valenz der Hypertonie und andererseits die Tatsache bedenkt, da? die KHK ihrerseits zu ca. 50% die Ursache der Herzinsuffizienz ist, dann wird der risikotr?chtige Zusammenhang zwischen Hypertonie und Herzinsuffizienz überdeutlich. Die arterielle Druckbelastung führt in einem l?ngeren Prozess von einer anf?nglichen konzentrischen linksventrikul?ren Hypertrophie mit verdickten W?nden zu einer schlie?lich resultierenden exzentrischen hypertrophierten Herzform. Die linksventrikul?re Geometrie gilt als unabh?ngiger prognostischer Marker. Neben pathophysiologischen Voraussetzungen werden in dieser Arbeit die Diagnostik, die therapeutischen Ziele und die medikament?sen Optionen bei Hypertonie und Herzinsuffizienz eingehend beschrieben. Das Ziel der Therapie, die Senkung des arteriellen Blutdrucks, die Rückbildung der linksventrikul?ren Hypertrophie und somit der Verbesserung der klinischen Symptomatik und der Prognose, ist unter Medikation durchaus erreichbar. Nicht unerw?hnt sollte bleiben, wie wichtig die Mitarbeit der Patienten hinsichtlich Lebensführung und Vermeidung bzw. Reduktion von Risikofaktoren der Hypertonie ist.