The introduction of non-invasive, portable, automatic blood pressure measurement devices enables characterization of the blood pressure profile throughout the day in an ambulatory setting. The article advises against uncritical use. 24-hour ambulatory blood pressure measurements have become a valuable tool in scientific research, however, especially in studies dealing with antihypertensive efficacy. In hypertensive patients with "white coat hypertension", important data cannot be obtained without the use of 24-hour ambulatory blood pressure monitoring or blood pressure measurement at home.
Calcium antagonists are widely used in the treatment of hypertension. However, few endpoint studies with calcium antagonists have been done to prove reduction in hypertensive complications. Results of the STONE, SYST-EUR and SYST-CHINA studies show that long-acting calcium antagonists are effective compared to placebo, especially in patients with isolated systolic hypertension and diabetes. Ongoing prospective and randomized trials like STOP II, INSIGHT, NORDIL, ALLHAT and ASCOT will clarify whether calcium antagonists are more effective than well-proven diuretics and betablockers. ASCOT will test the hypothesis that amlodipine is more efficacious than atenolol in preventing cardiac complications in 18,000 hypertensive patients with high coronary risk including diabetes (among them, 2,000 in Norway). The study is also randomizing the patients in a factorial design to either atorvastatin or placebo, testing the so-called lipid hypothesis.
Vascular hypertrophy and insulin resistance have been associated with abnormal left ventricular (LV) geometry in population studies. We wanted to investigate the influence of vascular hypertrophy and insulin resistance on LV hypertrophy and its function in patients with hypertension. In 89 patients with essential hypertension and electrocardiographic LV hypertrophy, we measured blood pressure; insulin sensitivity by hyperinsulinaemic euglucaemic clamp; minimal forearm vascular resistance (MFVR) by plethysmography; intima-media cross-sectional area of the common carotid arteries (IMA) by ultrasound; and LV mass, relative wall thickness (RWT), systolic function and diastolic filling by echocardiography after two weeks of placebo treatment. LV mass index correlated to IMA/height (r=0.36, P=0.001), serum insulin (r=-0.25, P
Several studies have been published recently on the effect of calcium-antagonists in the treatment of hypertension and heart failure. Except for an American case-control study, in which negative results may have been caused by selection bias, other studies show that calcium-antagonists have a positive effect. They appear to reduce cardiovascular complications, lower mortality and slow down the progression of atherosclerosis. However, large trials of adequate design and force are in progress (STOP II, NORDIL, HOT, INSIGHT, ALLHAT). It is hoped that the results of these trials will clarify whether calcium-antagonist are warranted in the treatment of hypertension and associated cardiovascular disease.
The only antihypertensive treatment regimen with documented effect on morbidity and mortality from stroke and coronary heart disease is based on diuretics and/or beta-blockers. However, new antihypertensive drugs are now widely used. These compounds may also prevent cardiovascular complications, but, as yet, this has not been proven. The clinical trials of the 1990s such as STOP II, CAPPP and NORDIL will test whether antihypertensive treatment with ACE-inhibitors and calcium-blockers are more effective than diuretics and beta-blockers in preventing cardiovascular complications. Also, a large-scale study (HOT) is being undertaken to examine how far diastolic blood pressure should be treated, and whether a small dose of aspirin has a protective effect when combined with good control of blood pressure. These studies will hopefully lead to better guidelines for the future treatment of hypertension.
BACKGROUND: The metabolic cardiovascular syndrome is the label given to the clustering of unfavourable levels of a number of coronary risk factors in subjects with high resting blood pressures. We found recently that exercise blood pressure had a strong independent prognostic value. OBJECTIVE: To search for possible similar associations between exercise blood pressure levels and coronary risk factors by studying conventional and recently acknowledged coronary risk factors. METHODS: The study population comprised 1999 healthy men aged 40-59 years. Age-adjusted coronary risk factor levels and their relation to resting and exercise blood pressures were studied. Resting blood pressure was measured after subjects had rested supine for 5 min. The exercise blood pressure used was the systolic blood pressure measured with the subject sitting on a bicycle ergometer at the end of a work load of 600 kpm/min (100 W) for 6 min. RESULTS: Besides corroborating the relation between the metabolic syndrome and resting blood pressure levels, we observed similar or even stronger associations between levels of various coronary risk factors and exercise blood pressure. We found rather strong, direct associations between exercise blood pressure and total cholesterol level, fasting triglyceride level and body mass index whereas inverse relations were found for glucose tolerance, physical fitness, pulmonary functioning and the ability to increase heart rate during exercise. Virtually all these associations had a level of statistical significance of P
Differences in clinical effectiveness between angiotensin-converting enzyme inhibitors (ACEis) and angiotensin receptor blockers (ARBs) in the primary treatment of hypertension are unknown. The aim of this retrospective cohort study was to assess the prevention of type 2 diabetes and cardiovascular disease (CVD) in patients treated with ARBs or ACEis. Patients initiated on enalapril or candesartan treatment in 71 Swedish primary care centers between 1999 and 2007 were included. Medical records data were extracted and linked with nationwide hospital discharge and cause of death registers. The 11,725 patients initiated on enalapril and 4265 on candesartan had similar baseline characteristics. During a mean follow-up of 1.84 years, 36,482 patient-years, the risk of new diabetes onset was lower in the candesartan group (hazard ratio (HR) 0.81, 95% confidence interval (CI) 0.69-0.96, P=0.01) compared with the enalapril group. No difference between the groups was observed in CVD risk (HR 0.99, 95% CI 0.87-1.13, P=0.86). More patients discontinued treatment in the enalapril group (38.1%) vs the candesartan group (27.2%). In a clinical setting, patients initiated on candesartan treatment had a lower risk of new-onset type 2 diabetes and lower rates of drug discontinuation compared with patients initiated on enalapril. No differences in CVD risk were observed.
Insulin resistance is related to physical inactivity, which is a risk factor for cardiovascular disease and death. Moreover, blood pressure responses during the first 6 minutes of an exercise test (600 kilo/pound/meter [kpm] per min) are more predictive for cardiovascular morbidity and mortality than blood pressure at rest, which could reflect that exercise blood pressure correlates more closely to peripheral structural vascular changes than casual blood pressure. We have recently shown a correlation between insulin resistance and minimal forearm vascular resistance (MFVR) in young men recruited from the highest blood pressure percentiles during a military draft session. In the present study, we tested the hypotheses that insulin sensitivity relates to physical fitness and that blood pressure responses during an exercise test relate to peripheral structural vascular changes in these men; we also tested whether these findings were interrelated. We assessed insulin sensitivity and physical fitness in 27 young men randomly selected from the cohort having a blood pressure of 140/90 mm Hg or higher during the compulsory military draft session in Oslo. Insulin sensitivity correlated with physical fitness (r=0.58, P=0.002). Systolic blood pressure after 6 minutes of exercise (600 kpm/min) correlated with MFVR (r=0.46, P=0.015). MFVR and physical fitness independently explained 60% of the variation in insulin sensitivity, and MFVR independently explained 19% of the variation of systolic blood pressure after 6 minutes of exercise. In conclusion, insulin sensitivity is related to physical fitness and exercise blood pressure to structural vascular properties in these young men.