Hypertension paradox

What is the paradox?

Dr Aram Chobanian, a world-renowned cardiologist and the Dean of the Boston University Medical School, wrote in the NEJM special article that despite the remarkable successes in lowering blood pressure in patients with hypertension, the prevalence of hypertension continues to increase worldwide. The number of people with uncontrolled blood pressure is also increasing.

He reviewed the development of the anti-hypertensive drug therapy and other evolving approaches such as lifestyle modifications. He recommended a new treatment algorithm for the management of stage 1 and 2 hypertension.

He noted that recent data indicated that about 28% of Americans with hypertension are unaware of their condition, 39% are not receiving treatment and 65% do not have their BP controlled. The controlled rates are even worse in patients with chronic kidney disease, diabetes, and other cardiovascular dysfunction in whom target BP levels of 130/80 mm Hg are recommended.

With the prevalence of hypertension continues to increase worldwide, he asked “what can be done to reverse this trend”. He pointed out that “salt intake and body weight are particularly important in the age-related increase in BP” but some countries such as Finland and GB have achieved significant reductions in dietary sodium through aggressive efforts including education and working with the food industry.

He said that “the failure to adopt healthy lifestyles has been a critical factor in this increase” and must be addressed urgently. He urged a national strategy to promote physical activities combined with changes in dietary intake.

This article was presented as the Shattuck lecture of the Massachusetts Medical Society and available as open access at the NEJM website.

Source: “The Hypertension Paradox — More Uncontrolled Disease despite Improved Therapy” NEJM 2009, 361(9):878-887

Conventional blood pressure test has no prognostic value

Researchers enrolled 556 people aged 65 on average who had high blood pressure despite having been treated with anti-hypertensive drugs and followed up for 4.8 years to determine which form of blood pressure monitoring was a better predictor of risk of cardiovascular disease in people with medication-resistant high blood pressure.

They found that conventional surgery-measured BP did not predict strokes or heart attacks, but readings taken over 24-hour period could. Critics say conventional blood pressure testing by a GP remains essential and is invaluable in detecting and monitoring high blood pressure that often has no symptoms and is difficult to detect.

Source: Salles GF, Cardoso CRL, Muxfeldt ES. Prognostic Influence of Office and Ambulatory Blood Pressures in Resistant Hypertension. Archive of Internal Medicine 2008; 168: 2340-2346
(f/t via Athens)

Statins may also reduce blood pressure

The Telegraph reported a randomized, double-blind, placebo-controlled trial involving 973 men and women who did not have high blood pressure and cardiovascular disease. Researchers found that two types of statins - simvastatin and pravastatin, modestly but significantly reduced blood pressure of the group compared with the placebo. The reductions ranged from 2.4 to 2.8 mm Hg for both SBP and DBP.

The researchers said that these reductions "may contribute to the reduced risk of stroke and cardiovascular events reported on statins", but critics said it is not possible to say whether statins have similar effects in people with high blood pressure.

Source: "Reduction in Blood Pressure With Statins - Results From the UCSD Statin Study, a Randomized Trial" Archive of Internal Medicine. 2008;168(7):721-727.

Vaccine can cut high blood pressue

The Guardian and other news source reported that a team of Swiss scientists has developed a vaccine that targets angiotensin II to reduce blood pressure significantly.

The findings, published in The Lancet, were based on a 14 week multicentre, double-blind, randomised, placebo-controlled trial involving 72 patients with mild-to-moderate hypertension. The patients received randomly injections of either 100 μg or 300 μg of the vaccine or placebo.

The researchers found that systolic and diastolic blood pressure fell by 9mm and 4mm respectively in patients given 300 μg of the vaccine, especially in the morning, but no change in blood pressure in the placebo group. They said the findings were promising but large-scale trials were needed.

Source: "Effect of immunisation against angiotensin II with CYT006-AngQb on ambulatory blood pressure: a double-blind, randomised, placebo-controlled phase IIa study" The Lancet 2008; 371:821-827 Number 9615 ( full text via Athens)

Pedometer - a perfect gift for motivating physical activity.

A review of 8 randomized controlled trials and 18 observational studies with a total of 2767 participants was carried out to evaluate the association of pedometer use with physical activity and health outcomes, according to an article in JAMA.

The study found that pedometer users in RCTs significantly increased their physical activity by 2491 steps per day more than control participants while those in observational studies 2183 steps per day over baseline. The pedometer users significantly decreased their body mass index by 0.38, the intervention participants significantly decreased their systolic blood pressure by 3.8 mm Hg. However, whether these changes are durable over the long term is undetermined.

A pedometer counts steps a person takes and the distance he/she has walked and has become popular as an everyday exercise motivator - a perfect Christmas gift for someone who wants to increase physical activitity and improve health.

Source : "Using Pedometers to Increase Physical Activity and Improve Health - Systematic Review" JAMA. 2007;298(19):2296-2304. (abstract only)

A little dark chocolate daily lowers blood pressure

A German study of 44 adults showed that eating a small amount of dark chocolate every day could lower blood pressure without increasing weight or other health risks.

Researchers stressed that although the reduction in blood pressure was small, the effects are clinically noteworthy. They also suggested asking people to consume just 6 g of dark chocolate daily would be much easier than encouraging them to stick to complex diet programs to help them reduce their blood pressure.

The British Heart Foundation warned chocolate is high in fat and calories and is not good for the heart.

The study is published in the July 4 issue of JAMA - "Effects of Low Habitual Cocoa Intake on Blood Pressure and Bioactive Nitric Oxide - A Randomized Controlled Trial" JAMA. 2007;298:49-60.