The Anglo-Scandinavian Cardiac Outcomes Trial (ASCOT), the world's largest study of hypertensive patients has proved that Amlodipine-based regimen reduces risk of new-onset diabetes by 34 per cent in hypertensive patients. The study, which began in 1998, enrolled 19,257 patients in the United Kingdom, Ireland, Sweden, Norway, Denmark, Finland, and Iceland.
The outcomes of the study showed that patients on the Amlodipine-based regime as compared to currently practiced beta-blocker treatment benefited from 11 percent reduction in total mortality, 23 percent reduction in fatal and non-fatal strokes and 24 per cent reduction in cardiovascular death.
The results of the five-year long trial, which were announced early this month at the World Congress of Cardiology in Barcelona, compared the widely used regimen of the beta-blocker, Atenolol with the calcium channel blocker, Amlodipine in nearly 20,000 patients. It proved that Amlodipine reduces the risk of onset of diabetes in hypertensive patients by 34 per cent when compared to the currently preferred treatment.
According to Professor Neil Poulter, a member of the Executive Committee of the ASCOT study, "These findings have critically important implications for patients . Hypertension already increases the risk of diabetes by two to three times. Now we know that the commonly used combination of a beta-blocker plus or minus diuretic significantly increases the risk compared with a new combination, Amlodipine plus or minus Perindopril. Therefore physicians should be cautious before prescribing the beta-blocker-based strategy to treat hypertension."
In India, there has been a steady increase in hypertension prevalence in the last few decades. In urban areas, the number of coronary heart disease cases has increased from two per cent in 1960 to 10.5 per cent in 2000. Hypertension along with diabetes is known to increase the risk of developing strokes and heart attacks. With one out of every three deaths in India being attributed to cardiovascular diseases, the results of the ASCOT study will have a significant impact, stated Dr Jamshed Dalal, Consultant Cardiologist - Lilavati Hospital.
Acting on the study results, a number of leading organizations like UK National Institute for Health and Clinical Excellence (NICE) working with the British Hypertension Society, have recommended that beta-blockers(angina, hypertension and cardiac arrhythmias management) should no longer be the preferred first line treatment for hypertension, and that a calcium-channel-blocker should be the first choice for initial therapy in hypertensive patients in ages above 55 because it would relaxes the smooth muscle in the arterial wall, decreases peripheral resistance and improves blood pressure.
If the therapy is initiated with Angiotensin Converting Enzyme Inhibitors (ACEI) / Angiotensin Receptor Blockers (ARB) a second drug which is a calcium-channel-blocker should be added to reduce the patient's risk of developing diabetes.
ASCOT was an investigator-led trial coordinated by an independent steering committee. In this trial, all patients had hypertension and at least three pre-specified cardiovascular risk factors such as being greater than or equal to 55 years old, a smoker and having a family history of coronary events. The average length of treatment was about 5.5 years.
Amlodipine besylate is a long-acting calcium-channel-blocker used as an anti-hypertensive. The drug is marketed by Pfizer as Amlogard in India, Norvasc in North America and as Istin in the United Kingdom as well as under various other names. Pfizer Inc funded the ASCOT trial.