The American Heart Association held its 2010 Scientific Sessions from November 13 to 17 in Chicago. The features below highlight some of the news emerging from the meeting.
» Benefits Observed With Experimental Cholesterol Drug
» A New Approach for Difficult Hypertension Cases
» PTSD Linked to Death, Atherosclerosis
» Smoking Rates Decline, But Cessation Efforts Still Warranted
» Scanning Matters When Managing Diabetics With Heart Disease
» Combination Therapy Effective in Heart Failure
The Particulars: Elevated LDL and low HDL cholesterol levels are risk factors for cardiovascular disease (CVD). Statins have been shown to reduce LDL and lessen CVD risk. Despite statin therapy, many patients still have a high risk of CVD. Anacetrapib is an experimental cholesteryl ester transfer protein (CETP) inhibitor. It is intended to block the ability of the CETP enzyme to transfer cholesterol particles from HDL to LDL cholesterol.
Data Breakdown: The DEFINE study (Determining the Efficacy and Tolerability of CETP Inhibition with Anacetrapib) was a randomized, double-blind trial of 1,623 patients who took either 100 mg anacetrapib or a placebo for 18 months. Patients were already being treated with a statin and/or other lipid-lowering medicine. Anacetrapib reduced LDL by 40%—from 81 mg/dL to 49 mg/dL. It also more than doubled the level of HDL cholesterol—from 40 mg/dL to 101 mg/dL—without raising blood pressure.
Take Home Pearls: Anacetrapib appears to more than double the level of HDL cholesterol and reduce LDL cholesterol without the blood pressure increase that has been linked to other CETP inhibitors. The full efficacy and safety of anacetrapib must be evaluated in a larger, phase III trial.
A New Approach for Difficult Hypertension Cases [back to top]
The Particulars: Resistant hypertension—hypertension that is uncontrolled despite use of antihypertensive medications—is relatively common, occurring in 15% to 20% of patients. Target blood pressure is usually unattainable with drug therapy in patients with severely-resistant hypertension. Therapeutic renal denervation (RDN) is a minimally invasive procedure in which a catheter-based probe is inserted into the renal artery to emit high-frequency energy to deactivate nerves near kidneys that are linked to high blood pressure.
Data Breakdown: A trial compared 52 participants who were randomly assigned to catheter treatment plus medication with 54 controls who received medication alone. Data at 6 months showed the treatment group’s systolic pressure fell an average of 33.4 mm Hg, while diastolic pressure dropped an average of 12.5 mmHg. In contrast, the control group’s average systolic pressure rose slightly (0.9 mmHg) and average diastolic pressure fell slightly (0.3 mm Hg). Blood pressure was reduced to less than 140/90 mm Hg in 39% of those who received RDN, compared with 6% of the control group.
Take Home Pearls: RDN appears to provide an effective non-drug method for controlling hypertension in patients who are unresponsive to multiple antihypertensive drugs. Future studies will evaluate the effects of RDN on heart attack, stroke, chronic kidney disease, and heart failure as well as hypertension.
PTSD Linked to Death, Atherosclerosis [back to top]
The Particulars: Post-traumatic stress disorder (PTSD) is a cluster of symptoms that can include emotional numbing, avoidance of certain situations, hyperarousal, sleep disruptions, and impaired concentration. War veterans are frequently affected by PTSD. Current PTSD treatment protocols involve providing relief of symptoms alone, but research has shown that these individuals may be at risk for cardiovascular disease (CVD).
Data Breakdown: Researchers studied electronic medical records of 286,194 veterans treated at VA medical centers. During an average follow-up of 10 years, researchers found that veterans diagnosed with PTSD had 2.41 times the rate of death from all causes compared with non-PTSD veterans. In a 637-veteran sub-study using a non-invasive technique to measure the amount of coronary artery calcium (CAC), 76.1% of veterans with PTSD showed at least some CAC, compared with 59% of non-PTSD veterans. Among veterans with calcium buildup, those with PTSD had a 48% greater risk of death from any cause and a 41% greater risk of death due to CVD when compared with non-PTSD veterans.
Take Home Pearls: PTSD appears to predict death independently of known CVD risk factors. Atherosclerosis appears to be a mechanism by which PTSD could increase the risk of CVD events. Early detection and management of cardiovascular risk factors in veterans with PTSD might delay the onset of cardiovascular disease.
Smoking Rates Decline, But Cessation Efforts Still Warranted [back to top]
The Particulars: Smoking is known to have significant effects on cardiovascular outcomes and has been shown to increase the risk of heart disease. Recent trends suggest that smoking cessation rates are improving.
Data Breakdown: The Minnesota Heart Survey, a population-based, serial cross-sectional study of trends in cardiovascular risk factors, examined the smoking trends in adults from 1980 to 2009. The number of current smokers was cut in half, decreasing from 32.8% to 15.5% in men and from 32.7% to 12.2% in women. Greater decreases were observed among adults with higher incomes and more education. Current smokers were smoking less, decreasing their average number of cigarettes smoked per day from 23.5 to 13.5 in men and 21.1 to 10.0 in women. Fewer people started smoking; ever-smokers dropped from 71.6% to 44.2% in men and from 54.7% to 39.6% in women.
Take Home Pearls: The proportion of adult smokers appears to have decreased dramatically during the past 30 years and more people are quitting while fewer are starting to smoke. Although smoking cessation efforts have made an impact, more emphasis needs to be placed on individuals in lower-income brackets and those with less education.
Scanning Matters When Managing Diabetics With Heart Disease[back to top]
The Particulars: More than 23 million adults in the United States have diabetes, one of the strongest risk factors for heart disease. Previous research has shown that there were no fewer deaths and heart attacks in people who had medical treatment along with prompt revascularization than in those who received only intensive treatment to manage blood glucose, blood pressure, and cholesterol levels over 5 years.
Data Breakdown: The BARI 2D (Bypass Angioplasty Revascularization Investigation 2 Diabetes) trial compared various treatment strategies for patients with both type 2 diabetes and heart disease. A sub-study of BARI 2D was conducted in 1,505 participants who underwent an imaging procedure that located and measured areas of heart muscle receiving sufficient blood flow. At 1 year, 59% of revascularization patients and 49% of medical patients had normal results with no drug-induced ischemia. Reductions in blood flow involved 3% of the heart tissue in revascularization patients and 9% of heart muscle in medical patients. More ischemia was associated with a greater risk of death or heart attack.
Take Home Pearl: There appears to be significant value in scanning patients with diabetes and heart disease who are being managed with medication and lifestyle interventions.
Combination Therapy Effective in Heart Failure [back to top]
The Particulars: Almost 6 million adults in the United States have heart failure. Mild cases can cause breathlessness and fatigue, and untreated symptoms tend to worsen. Previous studies have shown that cardiac resynchronization therapy (CRT) combined with implantable cardioverter defibrillator (ICD) treatment can reduce symptoms and hospitalizations among patients with severe heart failure, but the effect of this approach on patients with milder symptoms and on death rates are unclear.
Data Breakdown: Investigators randomized patients with mild to moderate heart failure to receive either an ICD or an ICD equipped to provide CRT. Both groups also received standard heart failure medications. Patients on the combined ICD/CRT regimen were 25% less likely to die or be hospitalized for heart failure when compared with patients who did not receive CRT. Patients on the combined ICD/CRT treatment were also 25% less likely to die of any cause when compared with patients who did not receive CRT.
Take Home Pearls: Adding ICD therapy to CRT appears to significantly reduce mortality and heart failure hospitalizations among patients with mild-to-moderate symptoms being treated with medication. Researchers will next analyze the cost-effectiveness of ICD/CRT compared with ICD-only and quality-of-life data.
Readings & Resources (click to view)
For more information on these items and other research that was presented at the American Heart Association’s 2010 Scientific Sessions, go to: http://scientificsessions.americanheart.org.