From efficacy in trials to effectiveness in clinical practice: The Swedish Stroke Prevention Study.

Blood pressure treatment has shown great efficacy in reducing cardiovascular events in randomized controlled trials. If this is effective in reducing cardiovascular disease in the general population, is less studied. Between 2001 and 2009 we performed an intervention to improve blood pressure control in the county of Västerbotten, using Södermanland County as a control. The intervention was directed towards primary care physicians and included lectures on blood pressure treatment, a computerized decision support system with treatment recommendations, and yearly feed back on hypertension control. Each county had approximately 255 000 inhabitants. Differences in age and incidence of cardiovascular disease were small. During follow-up, more than 400 000 patients had their blood pressure recorded. The mean number of measurements was eight per patient, yielding a total of 3.4 million blood pressure recordings. The effect of the intervention will be estimated combining the blood pressure data collected from the electronic medical records, with data on stroke, myocardial infarction and mortality from Swedish health registers. Additional variables, from health registers and Statistics Sweden, will be collected to address for confounders. The blood pressure data collected within this study will be an important asset for future epidemiological studies within the field of hypertension.

Should beta blockers remain first choice in the treatment of primary hypertension? A meta-analysis.

BACKGROUND: Beta blockers have been used widely in the treatment of hypertension and are recommended as first-line drugs in hypertension guidelines. However, a preliminary analysis has shown that atenolol is not very effective in hypertension. We aim to substantially enlarge the data on atenolol and analyse the effect of different beta blockers. METHODS: The Cochrane Library and PubMed were searched for beta blocker treatment in patients with primary hypertension. Data were then entered into the Cochrane Collaboration Review Manager package and were summarised in meta-analyses. 13 randomised controlled trials (n=105 951) were included in a meta-analysis comparing treatment with beta blockers with other antihypertensive drugs. Seven studies (n=27 433) were included in a comparison of beta blockers and placebo or no treatment. FINDINGS: The relative risk of stroke was 16% higher for beta blockers (95% CI 4-30%) than for other drugs. There was no difference for myocardial infarction. When the effect of beta blockers was compared with that of placebo or no treatment, the relative risk of stroke was reduced by 19% for all beta blockers (7-29%), about half that expected from previous hypertension trials. There was no difference for myocardial infarction or mortality. INTERPRETATION: In comparison with other antihypertensive drugs, the effect of beta blockers is less than optimum, with a raised risk of stroke. Hence, we believe that beta blockers should not remain first choice in the treatment of primary hypertension and should not be used as reference drugs in future randomised controlled trials of hypertension.

Atenolol in hypertension: is it a wise choice?

BACKGROUND: Atenolol is one of the most widely used beta blockers clinically, and has often been used as a reference drug in randomised controlled trials of hypertension. However, questions have been raised about atenolol as the best reference drug for comparisons with other antihypertensives. Thus, our aim was to systematically review the effect of atenolol on cardiovascular morbidity and mortality in hypertensive patients. METHODS: Reports were identified through searches of The Cochrane Library, MEDLINE, relevant textbooks, and by personal communication with established researchers in hypertension. Randomised controlled trials that assessed the effect of atenolol on cardiovascular morbidity or mortality in patients with primary hypertension were included. FINDINGS: We identified four studies that compared atenolol with placebo or no treatment, and five that compared atenolol with other antihypertensive drugs. Despite major differences in blood pressure lowering, there were no outcome differences between atenolol and placebo in the four studies, comprising 6825 patients, who were followed up for a mean of 4.6 years on all-cause mortality (relative risk 1.01 [95% CI 0.89-1.15]), cardiovascular mortality (0.99 [0.83-1.18]), or myocardial infarction (0.99 [0.83-1.19]). The risk of stroke, however, tended to be lower in the atenolol than in the placebo group (0.85 [0.72-1.01]). When atenolol was compared with other antihypertensives, there were no major differences in blood pressure lowering between the treatment arms. Our meta-analysis showed a significantly higher mortality (1.13 [1.02-1.25]) with atenolol treatment than with other active treatment, in the five studies comprising 17671 patients who were followed up for a mean of 4.6 years. Moreover, cardiovascular mortality also tended to be higher with atenolol treatment than with other antihypertensive treatment. Stroke was also more frequent with atenolol treatment. INTERPRETATION: Our results cast doubts on atenolol as a suitable drug for hypertensive patients. Moreover, they challenge the use of atenolol as a reference drug in outcome trials in hypertension.