American Society of Hypertension 2014 Annual Scientific Meeting

June 2, 2014
Cardiology Review® Online, June 2014, Volume 30, Issue 3

The American Society of Hypertension (ASH) is the largest US professional organization dedicated to eradicating hypertension and its consequences. The following study presentations were highlights of the organization's 29th annual meeting in New York City.

American Society of Hypertension 2014 Annual Scientific Meeting

New York, NY, May 15-20, 2014

The American Society of Hypertension (ASH) is the largest US professional organization dedicated to eradicating hypertension and its consequences. The following study presentations were highlights of the organization’s 29th annual meeting in New York City.

Hyperkalemia Not Infrequent With Spironolactone in Resistant HTN

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small retrospective study assessing the safety of spironolactone in patients with resistant hypertension found that hyperkalemia is not an infrequent occurrence, and thus further study is needed to understand the safety of the drug in this population. Joel Marrs, MD, of the University of Colorado, Aurora, presented the findings of a study of 73 people with resistant hypertension treated with spironolactone, in whom 8.2% had hyperkalemia. Four patients stopped taking the drug because of elevated potassium levels, and 1 patient developed hyperkalemia that resulted in a visit to the emergency department. Two patients developed an increase in potassium >2.0 mmol/L from baseline but the average increase in potassium levels among the study participants was 0.2 mmol/L.

Patients with compromised renal function were more likely to develop hyperkalemia than those with healthier kidneys.

Dr. Marrs said much of the benefit of spironolactone, where it’s been studied, is as the fourth agent after use of the more common blood-pressure—lowering agents. “There are data showing a pronounced lowering of blood pressure when it’s added,” he said. “We’re seeing it used more and more in resistant hypertension.” Spironolactone is effective, but it raises potassium levels. The main concern with elevated potassium levels is the onset of arrhythmias, said Dr. Marrs, who noted that RALES (Randomized Aldactone Evaluation Study) showed a statistically significant 3-fold increased risk of hospitalization related to hyperkalemia in patients with heart failure who received spironolactone and an angiotensin-converting enzyme inhibitor.

Dr. Marrs stressed the important of ensuring adequate monitoring of patients when spironolactone is added, and he recommends that potassium levels are checked within 1 to 2 weeks after therapy is initiated.

The study’s abstract, by Chomicki et al, was published in volume 8, issue 4 supplement of the Journal of the American Society of Hypertension (2014;e30-e31).

BP Control Gaps Between Insured, Uninsured Widen

Americans without health insurance are falling behind their in

sured counterparts and not benefiting from advances in hypertension care, according to findings from the National Health and Nutrition Examination Surveys (NHANES) by Brent Egan, MD, and colleagues, presented at the ASH 2014 Annual Scientific meeting.

Dr. Egan said that among Americans with health insurance, the percentage of those with adequate control of blood pressure increased in recent years, while there is no change in the percentage of individuals without insurance who had blood pressure levels at targets recommended by guidelines.

The researchers found that in 1988 to 1994, there was no statistical difference in the number of patients with insurance and without insurance who were at the recommended blood pressure goal of <140/90 mm Hg. In the latest NHANES analysis from 2005 to 2010, however, the percentage of insured patients who achieved the blood pressure target increased to 52.5%; hypertension control in those without insurance was achieved in only 29.8% of patients.

Uninsured patients were also less likely to be aware they had hypertension, less likely to be treated when they were aware, and less likely to be controlled when they were treated. Dr. Egan said each factor contributed roughly equally to the difference between the insured and uninsured patients with blood pressure control. He also said that the percentage of insured patients who visited a physician 0 to 1 time in the past year decreased from the earlier time span to 2005 to 2010. Approximately 80% of insured patients in the latest survey were seeing a physician at least twice per year. In the uninsured population, 50% saw a physician 2 or more times per year (a figure that didn’t change since the 1988 to 1994 survey).

Despite the introduction of the Affordable Care Act, said Dr. Egan, there will remain a large number of US adults without insurance, estimated to be about 31 million people.

The study’s abstract, by Egan et al, was published in volume 8, issue 4 supplement of the Journal of the American Society of Hypertension (2014;e7-e8).

One-Third of YouTube Videos on BP, HTN Misleading

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new study by Nilay Kumar, MD, and colleagues finds that one-third of videos on YouTube that pertain to hypertension and blood pressure contain inaccurate information, promoting unproven therapies and supplements for the treatment of hypertension.

Dr. Kumar said that many patients who visited him at the hypertension clinic arrived with information obtained on the Internet. “What they saw on the Internet was oftentimes misleading, was not recommended by the clinical guidelines, and was not considered standard of care,” he said.

He and his colleagues surveyed YouTube because of its tremendous database and “almost zero moderation.” A search of YouTube for hypertension and high blood pressure returned over 300,000 videos. The researchers studied the 400 most relevant or highly ranked videos, and classified them as useful, misleading, or based on patient experiences, and graded them on an objective 5-point scale for quality and reliability. Two physicians considered the content related to epidemiology, pathogenesis, symptoms, lifestyle modification, treatment, and alternative treatments.

One-third of the videos were classified as misleading; 64% were classified as “useful,” and 3% were based on a patient’s personal experience. Most of the misleading videos promoted the use of alternative treatments or seemed to misunderstand accepted standards of care, the researchers found. Among the alternative treatments advocated were acupuncture, acupressure, massage, and certain supplements, the most commonly promoted of which is L-arginine. Patients are trying all of these in the hopes they might work, even though there’s no strong evidence for any of them, Dr. Kumar noted.

The sources of videos were examined, with the most useful coming from academic medical centers or professional organizations, along with government organizations. Independent users uploaded 81% of the misleading videos.

Dr. Kumar recommended that physicians tell patients about trustworthy websites and sources of medical information, much as they would prescribe diuretics or calcium channel blockers for hypertension because, whether we like it or not, “Dr. Google” is on call.

The study’s abstract, by Kumar et al, was published in volume 8, issue 4 supplement of the Journal of the American Society of Hypertension (2014;e14-e15).

Nighttime Hypertension—Not Daytime or Clinic&mdash;Predicts MI, Stroke

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n analysis of over 13,000 patients shows that clinic-measured blood pressure had no association with the risk of cardiovascular outcomes including stroke, whereas nighttime blood pressure measurements were associated with a risk of adverse clinical outcomes. Lead investigator George Roush, MD, of St. Vincent’s Medical Center in Bridgeport, CT, said that for every 10-mm Hg increase in nighttime systolic blood pressure, the risk of cardiovascular outcome was increased 25%.

The analysis included European, South American, and Japanese patients who received 24-hour ambulatory blood-pressure monitoring (ABPM) and is one of the largest group of patients receiving ambulatory blood pressure monitoring with cardiovascular events as the outcome, according to Dr. Roush.

Individually, each 10-mm Hg increase in blood pressure assessed during nighttime, daytime, and during clinic visits was associated with a 25%, 20%, and 11% increased risk of myocardial infarction (MI) and stroke, respectively. After adjustment for multiple confounding variables such as age, gender, diabetes, and smoking status, only nighttime measurement of blood pressure was predictive of MI and stroke, the study found.

Dr. Roush said it is not yet known why nighttime blood pressure is more predictive of clinical outcomes compared with the other measurements, but he hypothesized that it might be because nighttime blood pressure is a marker for something else, such as elevated sympathetic tone.

The study’s abstract, by Roush et al, was published in volume 8, issue 4 supplement of the Journal of the American Society of Hypertension (2014;e59).

Dedicated Clinic for Resistant HTN Gets Results

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n Ohio clinic that specifically treats patients with resistant hypertension achieved significant reductions in systolic blood pressure compared with baseline values, and was also found to help reduce patients’ body weight and body mass index (BMI), according to data gathered by John Szawaluk, MD, director of the Resistant Hypertension Clinic, and his colleagues (Ohio Heart and Vascular Center, Cincinnati).

The results of their study, which followed 109 patients treated between January 2012 and September 2013, showed that patients referred to the clinic had a baseline systolic and diastolic blood pressure of 153.1/83.7 mm Hg. Approximately one-third were obese, nearly half had elevated cholesterol levels, and 20% had chronic kidney disease. Slightly more than 25% had underlying coronary artery disease.

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After 3.5 months (3 visits on average), systolic blood pressure was reduced to 130 mm Hg and diastolic blood pressure was reduced to 75.1 mm Hg; body weight was reduced from 94.5 kg to 91.4 kg, and BMI declined from 32.2 kg/mto 31.3 kg/m(neither change was significant).

The clinic includes a dietitian, nurse practitioners (NPs), and physicians. Dr. Szawaluk said the patients typically have a 60- to 90-minute first visit that includes 20 to 25 minutes with the NP, who determines what medications they are taking. This is in contrast to the usually brief 10- to 15-minute visit with family physicians that most patients get. There is time to offer comprehensive lifestyle advice and diet and exercise help that is more detailed than what patients normally get from family physicians. “What we’ve observed is that the lifestyle changes we recommend can be just as important as the medication changes we make,” says Dr. Szawaluk, and he notes that patients who are “resistant” to therapy often haven’t been adhering to therapy for a reason, including cost and side effects.

Most of the patients are taking at least 4 antihypertensive medications. Dr. Szawaluk prescribes angiotensin-converting enzyme (ACE) inhibitors or angiotensin-receptor blockers (ARBs), calcium channel blockers, and a diuretic; for a fourth medication, he frequently adds spirinoloactone and usually takes patients off atenolol.

The study’s abstract, by Gilardi et al, was published in volume 8, issue 4 supplement of the Journal of the American Society of Hypertension (2014;e57-e58).