"Doctors have long debated the effectiveness of a relatively new class of blood pressure medicines known as angiotensin receptor blockers or ARBs. Since they came on the market in  they have been widely used by patients  but usually only as a secondline therapy when older drugs had failed to work or when their side effects had become intolerable. Now a large new analysis involving  patients shows that these medications may be as effective and safe as their older cousins the angiotensin converting enzyme or ACE inhibitors. Sripal Bangalore an associate professor of cardiology at NYU Langone Medical Center who is lead author of the new study said in an interview that the previous studies comparing the two may have been misinterpreted due to what he called a generation gap in participants and changes in their health care and lifestyle choices. The idea that ACE inhibitors are more effective than ARBs was based on comparing studies on ACE inhibitors going as far back as the s and into the s with newer studies on ARBs in the s. These studies appeared to show a larger difference between ACE inhibitors and placebos versus ARBs and placebos. Most significantly research showed a significant effect in reducing the risk of death with ACE inhibitors but not with ARBS. That led many doctors and standards groups to conclude that ACE inhibitors were more effective than ARBs. But some doctors and researchers were puzzled by the fact that in headtohead comparisons between the two classes of drugs they appeared to equally safe and effective. If there really was such a big difference between the medications why didnt it show up in these types of studies That inconsistency created a confusing split in the medical community. Most guidelines set forth by the major medical groups suggest starting a patient with an ACE inhibitor first but the Joint National Committee on Prevention Detection Evaluation and Treatment of High Blood Pressure JNC considers ACE inhibitors and ARBs to be equal. Bangalore noticed that one assumption made in comparing the placebo trials  that the patients in the group were about the same  was incorrect. During that time period there was a remarkable shift in cardiovascular health care in America  with a greater emphasis on not smoking more statin use for cholesterol better management of diabetes lower targets for blood pressure. The patients in the s and s were a higherrisk group than those in the s Bangalore explained. If your risk is higher its easier to show a benefit. If your risk is lower its harder to show a benefit. The new analysis published in Mayo Clinic Proceedings on Monday involves a second look at  randomized trials with  patients that took place after  and shows that during this time period patient outcomes on the two medications were remarkably similar. The one difference they found was that ARBs tend to be better tolerated by patients meaning that they have fewer side effects or result in fewer adverse events. ACE inhibitors are poorly tolerated by many patients because they can produce a bothersome dry cough and some end up stopping medication as a result. Bangalore said this is critically important because compliance is big issue with our patients. With hypertension they are on these medications for decades and its important to choose one that will be the most tolerable he said. The other piece of good news regarding the medications is that ACE inhibitors as well as many ARBs are now generic  meaning that the cost difference is minimal. The study was limited to patients who did not have heart failure and because it involved a retrospective analysis of trials it was unable to control for differences in the design or data gathering of the previous work."