“Remarkable” long-term effects of blood pressure medicines
Important new study results show that medicines to lower blood pressure and cholesterol help prevent stroke deaths in people with high blood pressure – even ten years after the study ended
The ASCOT study was a major study which started in the late 90s in almost 20,000 people with high blood pressure. The aim was to find out whether new treatments for preventing heart attacks was better than older ones. The trial was stopped after about five years because of the obvious benefits of the new treatments. And 10-15 years later, those who took part are still benefiting.
The study looked at people between the ages of 40-79 with high blood pressure and other risk factors for heart disease. They were given either calcium channel blockers (Amlodipine) plus an ACE inhibitor (Perindopril) if needed, or the older medicines, beta blockers (Atenolol), plus a diuretic (Bendroflumethiazide) and potassium if needed.
In each group, some were also given a statin (Atorvastatin), which lowers blood cholesterol, and the others were given a placebo (a dummy pill).
Those who took calcium channel blockers and statins together were less likely to have a heart attack or stroke during the trial. 10 years later, in their mid to late 70s, they still seemed to have some protection.
The ASCOT Legacy trial
15 years after the trial began, the researchers based at Imperial College London and Queen Mary University of London, and many other UK sites, followed up a group of 8,580 people from the original trial. This is known as the ASCOT legacy trial, and the researchers announced their findings at the ESC Congress 2018.
Long term effects of blood pressure medicines
People who took calcium channel blockers for 5.5 years were 29% less likely to have died from a stroke ten years later than those taking beta-blockers. They also appear to be slightly less likely to have had a heart attack. Those at higher risk of stroke and heart attack had some benefit too, even if they didn’t take a statin.
Interestingly, the long-term benefits of blood pressure medicines did not seem to be due to differences in blood pressure in the original trial. The reason why isn’t known, but it could be that the calcium channel blockers reduced variability in blood pressure, or that the beta blockers had negative effects.
Long term effects of cholesterol medicines
Statins had a long-lasting effect too. People with average blood cholesterol (a level of 6.5mmol/l) or below who took a statin for 3.3-5.5 years were 15% less likely to have died from a disease of the heart and blood vessels such as heart attacks or stroke 16 years later.
The reason why isn’t properly understood, but could be because they stabilize the parts of the arteries where fat has built up, protecting against blood clots forming.
The study offers new evidence for these medicines
Professor Peter Sever from Imperial College London, who jointly led the study, called the results “remarkable”, explaining: "We have previously shown that statins confer long-term survival benefits after trials have stopped, but this is the first time it has been found with a blood pressure treatment."
Dr Ajay K. Gupta, of the William Harvey Research Institute, Queen Mary, said: "The findings provide further support for the use of an effective blood pressure lowering therapy plus a statin in most patients with high blood pressure."
Professor Mark Caulfield, Director of the William Harvey Research Institute, said: "This study confirms the importance of lowering blood pressure and cholesterol to prevent disabling and life-shortening cardiovascular disease."
The study does have some limitations. For example, it doesn’t include any information on treatments given after the trial. It also doesn’t include information on illness, only death rates.
Professor Graham MacGregor, Chairman of Blood Pressure UK, says: “Before now, the long-term effects of lowering blood pressure and cholesterol with medications hasn’t been well documented in clinical trials. These long-term findings should give added reassurance to the doctors who prescribe them and those who take them."
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