Highlights from the American Heart Association Scientific Sessions
Vitamin D and heart disease, the effectiveness of external defibrillators and more from the Orlando, Fla., meeting
By Nathan Seppa
Vitamin D for the heart
Giving vitamin D to patients after they’ve survived a heart attack or a close call lowers their levels of two compounds implicated in heart disease. Yoav Arnson of Meir Medical Center in Kfar Saba, Israel, and colleagues identified 50 patients who had a heart attack or an episode of unstable angina — a cardiac red alert. All the patients were immediately started on standard drugs and half were randomly selected to also get 4,000 international units of vitamin D daily. After five days, the vitamin D group showed a decrease in the inflammation-causing compounds called vascular cell adhesion molecule-1 and interleukin-6. VCAM-1 is central to atherosclerotic plaque formation and IL-6 is broadly associated with coronary risk. Patients not getting vitamin D showed clear increases in both compounds during the five days. This could explain some of the vitamin’s cardio-protective properties, Arnson reported November 15.
Clean teeth: More than good-looking
People who get the plaque scraped off their teeth may be less likely to have a heart attack, Emily Chen of Taipei Veterans General Hospital in Taiwan reported November 13. Chen and colleagues tracked the health of more than 100,000 people, roughly half of whom reported getting their teeth cleaned by a dentist or a dental hygienist at some point. The heart attack rate in these people over seven years of follow-up was one-fourth lower than in those who didn’t report any cleanings. Poor oral health leading to gum disease has been tied to chronic infection and heart disease, but few studies have explored the prospective benefits of preventing it. Teeth cleaning provided only minimal protection against stroke.
Wearable heart zappers do the trick
Small heart defibrillators worn by nearly 5,000 people in the United States deliver some needless shocks but correctly fix potentially lethal heart arrhythmias in about nine out of 10 times in which they are needed, Vincent Mosesso Jr. of the University of Pittsburgh reported November 13. These external defibrillators, which deliver a shock if they sense an irregular heartbeat, are given to people with very weak heart function who are awaiting a heart transplant or who have a condition that prevents them from getting an implanted defibrillator. The researchers combed through records of more than 14,000 devices in use over three years and found that 185 people received a shock in response to an irregular heartbeat, with the heart returning to normal rhythm 91 percent of the time. Another 213 people got zapped unnecessarily, but none died from it.
Vitamin C shows benefit
Low intake of vitamin C has been associated with high levels of C-reactive protein, an inflammatory protein implicated in heart disease. A new study of 212 heart failure patients found that those with low vitamin C and high CRP had an increased risk of dying or of their condition getting worse. Eun Kyeung Song of the University of Ulsan in South Korea and colleagues measured CRP levels in the patients’ blood, and the participants — nearly half of whom had moderate to severe disease — completed a four-day diet questionnaire. Those data indicated more than one-third of the patients had vitamin C deficiencies. Over one year, those with low vitamin C and high CRP levels were about twice as likely to die or be hospitalized due to heart problems than those with normal levels, Song reported November 13.
Anti-cholesterol shot lasts a month
A single injection of an experimental drug can lower LDL, the bad cholesterol, for up to 30 days, Clapton Dias of Amgen reported November 14. The drug works by inhibiting a natural compound in the body called PCSK9 that pushes up circulating LDL levels. Dias and colleagues treated 42 healthy adults with various doses of the drug by intravenous injection or a routine shot. Fourteen other volunteers received a placebo shot. LDL levels monitored for up to 113 days showed no change in the placebo recipients but decreased by up to 64 percent within two weeks in people getting the highest dose of the drug, called AMG145. The drug suppressed LDL for a month before the effect began to tail off. The researchers said the shots could boost drug compliance in some patients and help others with stubbornly high LDL that fails to respond fully to other anti-cholesterol drugs.