Three recent studies looking at blood pressure treatment and responses in various population groups, suggest that there is a lot more to hypertension treatment than simple trial and error prescribing.
Hypertension is an unhealthy increase of blood pressure on the arteries. As the Wall Street Journal explained, “the pressure is governed by the body’s intricate plumbing mechanism: The heart is the pump, the arteries are the pipes, and the kidneys are sewers that eliminate unwanted fluids. Blood pressure can go up either because there’s too much fluid (salt and water) in the system, or because the arteries have narrowed. Blood pressure can rise with a diet that is high in salt.”
What is significant about hypertension is that of the 50 million Americans who suffer from the disease, nearly half don’t succeed in keeping their blood pressure under control, often because they haven’t been prescribed the drug that would work best for them. One of the factors causing this problem is that there are “five types of drugs commonly used for treating hypertension, or high blood pressure, a major risk factor for heart attacks and stroke.”
Some of the most common therapies available to treat hypertension include “diuretics, which are cheap, well-tested, and have been around for decades. These drugs boost the release of fluid through the kidneys. Another drug class, beta blockers, slow the heart and thus lower the amount of blood that’s pumped. Ace inhibitors, alpha blockers and calcium channel blockers reduce pressure by dilating the blood vessels.”
The difficulty that arises from choosing these drugs is that “doctors often choose among the drugs by trial and error, prescribing several of them in turn to see which works best for a particular patient.” What makes the situation even more problematic for patients and doctors is that “most people need more than one drug to control high blood pressure, making it all the more difficult to ensure a patient is receiving the most effective treatment. In other words, “patients with different physical characteristics respond differently to various hypertension drugs.”
As a result, there is a strong need for more continuing medical education (CME) and custom medicine to address how patients can be given the correct treatment that is best for them. Fortunately, three new studies are now suggesting ways to help make sure patients get the right medications.
As Michael Alderman, a blood-pressure expert at the Albert Einstein College of Medicine in New York City, and a co-author of one of the new studies in hypertension pointed out, the “current prescribing methods are very primitive.” And a consequence of these primitive practices is that “we haven’t increased the success rate [in treating hypertension] in 35 years.” These comments demand the attention of the medical community to rethink methods and approaches for the diagnosis, prevention and treatment of hypertension.
Making it harder for doctors to find the right treatments for patients is that “little research has focused on matching specific pills to specific patients,” but the new studies, which appear in the latest issue of the American Journal of Hypertension, “represent efforts to provide scientific guidance for doctors treating high blood pressure.” For example:
– One of the studies shows that some drugs work better in certain ethnic groups than in others.
– Another study points to the importance of testing patients’ levels of renin, a hormone produced by the kidneys, as a guide in prescribing blood-pressure medicine.
Despite the fact that “researchers in each of the studies emphasized that larger-scale trials would be necessary before the findings could become part of official treatment guidelines,” their accomplishments demonstrate a significant breakthrough.
In addition, one of the studies, co-authored by Ajay Gupta of Imperial College London, looked at drug responses among 5,425 patients in various countries and across different ethnic groups. His research confirmed that south Asians, who are often given ace inhibitors as a first-line treatment, respond especially well to this line of treatment.
Dr. Gupta and his colleague’s research also showed that “medical-treatment guidelines, which say that first-line drug therapies should be guided by a patient’s age and race,” should also be applied for second-line treatments. For example, “if a calcium channel blocker is first prescribed, a diuretic should be the add-on drug. If a diuretic is first prescribed, a calcium channel blocker should be the second-line treatment.”
The two other studies, which focused on the hormone rennin, discussed how “few doctors today measure a patient’s renin level, despite a study in the 1970s that suggested it might be used as a biomarker for prescribing the drugs.” Despite “contradictory evidence that emerged later, which helped keep renin-testing from catching on, one of the new studies, involving 363 patients, confirmed the 1970s finding, showing that measuring the renin level can be an effective method for selecting a blood-pressure medication.”
Specifically, “the research, by a team led by Stephen Turner of the Mayo Clinic in Rochester, Minn., found that a patient with a higher renin level probably should not be treated with a diuretic.” Instead, the authors found that “the patient would probably respond better to a drug, such as a beta blocker, that functions differently in the body.”
This research also concluded that “the predictive effects of renin activity were statistically independent of race, age and other characteristics.” The research also “found that renin levels could also serve as a guide for prescribing add-on therapies for some patients.”
The third study, which involved 945 patients and was led by Dr. Alderman, “found that when an anti-renin drug was used in certain patients with low renin levels, it had the undesirable effect of increasing blood pressure.”
These studies demonstrate that more research and education is needed regarding the treatment of hypertension. In addition, the findings from these studies also “constitute a wake-up call that we should be using renin measurements as a systematic form of help” for prescribing hypertension drugs.
Ultimately, with a condition that affects over 50 million people this should be a main priority for physicians, researchers, and healthcare providers. One way to begin integrating the findings from this study into practice is by working with doctors and CME providers to establish programs that begin to measure and collect data regarding the methods doctors use in choosing hypertension drugs. Through more education about choosing the best methods for prescribing hypertension drugs, CME and custom medicine can begin to address these issues and help make hypertension patients healthier.