Findings of a long-term study of more than 8,500 people in the U.K. has found evidence that blood pressure and cholesterol-lowering drugs work to improve survival rates of their users after a decade of treatment.
The study revealed that the benefits of statins lasted more than a decade after the clinical trial closed. This new information gives credence to physicians’ use of blood pressure and cholesterol lowering drugs to improve survival in patients with hypertension. According to late breaking results from the Anglo-Scandinavian Cardiac Outcomes Trial (ASCOT) Legacy study presented Sunday at the European Society of Cardiology (ESC) Congress 2018 in Munich, Germany and published in The Lancet.
“Patients in their mid-60s with high blood pressure were less likely to die from heart disease or stroke by age 75–80 if they had taken both calcium channel blocker-based blood pressure lowering treatment and a statin,” said study co-author, Ajay K. Gupta, of the William Harvey Research Institute and Queen Mary University London, U.K. in a statement. “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. 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.”
According to Mayo Clinic, calcium channel blockers, or calcium antagonists, such as Amlodipine (Norvasc), Diltiazem (Cardizem, Tiazac, etc.), Felodipine and others treat a variety of conditions, such as high blood pressure, chest pain and Raynaud's disease. The medicine prevents calcium from entering cells of the heart and blood vessel walls, resulting in lower blood pressure. Also called calcium antagonists, the medication relaxes and widens blood vessels by affecting the muscle cells in the arterial walls. According to Mayo, some calcium channel blockers have the added benefit of slowing your heart rate, which can further reduce blood pressure, relieve chest pain (angina) and control an irregular heartbeat.
On the other hand, statins, such as atorvastatin (Lipitor), lovastatin (Altoprev), rosuvastatin (Crestor) and others, are drugs that lower cholesterol by blocking a substance your body needs to make cholesterol. Mayo clinic says statins may also help your body reabsorb cholesterol that has built up in plaques on your artery walls, preventing further blockage in your blood vessels and heart attacks.
The ASCOT Legacy study was investigator-led and funded in part by research grants from Pfizer to Imperial College London and the Foundation for Circulatory Health. It is the long-term follow-up of 8,580 patients from the U.K. who took part in the ASCOT study, which between 1998 and 2000 recruited patients with high blood pressure and three or more additional risk factors for cardiovascular disease.
Researchers reported that patients who took a newer blood pressure lowering treatment (based on a calcium channel blocker) for 5.5 years were 29% less likely to have died from a stroke ten years later than those taking an older regimen (based on a beta-blocker). Patients with average or below average blood cholesterol levels at the start of the trial who took a statin for 3-5 years were 15% less likely to have died from cardiovascular causes such as heart disease and stroke 16 years later than those taking a placebo, the study says.
Further, according to the researchers, a subgroup of patients with above average cholesterol who received standard lipid-lowering therapy for 5-1/2 years had 21% fewer cardiovascular deaths over ten years of follow-up with the newer blood pressure therapy compared to the older one.
“These results are remarkable,” said Professor Peter Sever, of the National Heart and Lung Institute at Imperial College London, U.K., and National Institute for Health Research senior investigator, who jointly led the study with Gupta. “We have previously shown that statins can confer long term benefits on mortality after trials have stopped, but to our knowledge it has never before been shown that for patients with high blood pressure there may be long term benefits on preventing cardiovascular deaths – particularly strokes in patients treated with a calcium chanel blocker-based regimen.”
The ASCOT trial initially set out to determine whether a new treatment strategy for high blood pressure was more effective in preventing heart attacks than the old strategy. Researchers wrote: “Patients with high blood pressure were randomly allocated to the new treatment of amlodipine (a calcium channel blocker) plus perindopril (an angiotensin-converting enzyme inhibitor) if needed to achieve the target blood pressure, or the old therapy of atenolol (a beta-blocker) plus bendroflumethiazide (a diuretic) and potassium if needed. The medicines were taken for a median of 5-1/2 years, when the trial was stopped because the newer treatment prevented more strokes and deaths,” After the trial, patients went on to receive their usual care.
Secondly, the trial was to discover if a statin would provide added protection against coronary heart disease in patients with high blood pressure and cholesterol levels below 6.5 mmol/L. Lastly, the trial evaluated the effectiveness of the newer versus older blood pressure lowering treatment in patients with high blood pressure and high cholesterol (above 6.5 mmol/l).
“This study confirms the importance of lowering blood pressure and cholesterol to prevent disabling and life-shortening cardiovascular disease,” said Professor Mark Caulfield, director of the William Harvey Research Institute.
Experts continued to debate the topic of statins for 40-to 75-year-olds in the U.S. earlier this year. “When it comes to using statins to prevent a first heart attack or stroke, one leading US guideline recommends the drugs to 9 million more people than the other, according to a study published in the Journal of the American Medical Association,” a CNN Health article stated in January.
"There's generally confusion on who should be getting statins," Michael Pencina, one of the study's authors and a professor of biostatistics and bioinformatics at the Duke Clinical Research Institute was quoted as saying. "I don't think we have the perfect guideline yet."
According to the article, “The first recommendation -- put out in 2013 by the American College of Cardiology and the American Heart Association -- covers 26.4 million Americans, the study estimated. This recommendation is based partly on a 10-year risk of stroke or heart disease, which can be plugged into a risk calculator. People over 40 with at least a 7.5% risk of these conditions are included in the guidelines.” The US Preventive Services Task Force (USPSTF), released its own recommendation in 2017—guidelines that cover an estimated 17 million Americans.