Trial: Cholesterol Treatment Trialists Collaboration
Patients (n): 18,686 diabetics 71,370 nondiabetics
Center: University of Oxford (UK) and Sydney University (Australia)
Drugs trialed: Statins
Statins, the most cost-effective cholesterol- lowering drugs, should be part of standard therapy for all diabetic individuals, aside from children and pregnant women, according to the recent study.
Researchers from University of Oxford, UK, and Sydney University, Australia, making up the Cholesterol Treatment Trialists Collaboration, conducted a large meta-analysis of 14 clinical trials and the health records of people with (18,686) and without (71,370) diabetes. The analysis, which is the most comprehensive to date, demonstrates that diabetes sufferers, in the same way as those not affected by the disease, can reduce their cardiovascular (CV) event risk through statin therapy, regardless of existing CV problems.
The data demonstrated a third reduction in CV events, such as heart attack or stroke, over a 5-year period for diabetics who were taking statins compared to those who were not, irrespective of gender or previous CV problems. Accordingly the researchers state that “Most people with diabetes should now be considered for statin therapy unless their risk is low (as in children) or statin therapy has been shown to be unsuitable for them (as in pregnancy).”
There were two recent studies not included in the meta-analysis as they found statins did not reduce CV disease risk. However, Colin Baigent, one of the reports’ authors said their inclusion would have affected the studies conclusions, since there were few patients enrolled and they were already extremely unwell. Furthermore he stated that statin treatment for all diabetes suffers from at least middle age is financially sounds since statins are cheap and effective.
“Generic statins are highly cost-effective, right down to an annual risk of about 1% per annum of a major vascular event, so it makes sense for statins to be used widely in most people with diabetes,” Baigent said.
Bernard Cheung of the University of Birmingham said in an accompanying editorial in the Lancet that “statins are among the most notable triumphs of modern medicine”. While he added that, in addition to drug treatment, lifestyle changes, such as the cessation of smoking, a healthy diet and regular exercise, are vital.
Diabetes, which is closely linked to obesity, is on the rise worldwide. At least 170 million people are estimated to have the disease and the number is predicted to at least double by 2030.
Details of these findings are published in The Lancet.
Source: Cholesterol Treatment Trialists' (CTT) Collaborators, Kearney PM, Blackwell L, Collins R et al. Efficacy of cholesterol-lowering therapy in 18,686 people with diabetes in 14 randomised trials of statins: a meta-analysis. Lancet 371, 117–125 (2008)
Heart attack survival may be greater in a public place than in hospital
A recent study suggested that should you suffer from a heart attack in a public place, such as an airport or even a casino, there is a 50% chance that you will survive, compared with just 33% if your heart attack occurs in a US hospital.
The study, which was published in the New England Journal of Medicine (NEJM), reveals that all too often patients do not get life-saving defibrillation within the crucial 2-min window when in hospital. Outside that time frame, the chances of survival are 22% compared with 40%.
The main problem is that in a hospital it is likely that you will be on your own when you suffer a heart attack, whereas if you are in a public place, such as an airport or casino, there will be lots of people around you. In a public place people will act immediately, while a patient on his/her own in a hospital ward may not get the same response.
A further explanation and confounding factor is that a patient in hospital is likely to be suffering from existing illness.
Source: Chan PS, Krumholz HM, Nichol G, Nallamothu BK; American Heart Association National Registry of Cardiopulmonary Resuscitation Investigators. Delayed time to defibrillation after in-hospital cardiac arrest. N. Engl. J. Med. 358, 9–17, (2008)
Healthy heart and mouth may be linked
Most people are aware that their lifestyle choices, such as food choice, exercise and smoking, can affect their cardiovascular health. But a new study has revealed that brushing and flossing your teeth may also assist in avoiding the potentially lethal disease.
Researchers from Howard University, (DC, USA) have found that periodontal patients whose bodies show evidence of a reaction to the bacteria associated with periodontitis may have an increased risk of developing cardiovascular disease.
“Although there have been many studies associating gum disease with heart disease, what we have not known is exactly why this happens and under what circumstances,” said Journal of Periodontology editor Kenneth Kornman. “The findings of this new analysis of previously published studies suggest that the long-term effect of chronic periodontitis, such as extended bacterial exposure, may be what ultimately leads to cardiovascular disease.”
The team conducted a meta-analysis of 11 studies that had previously examined clinically diagnosed periodontal disease and cardiovascular disease. The team then analyzed the participants’ levels of systemic bacterial exposure, specifically looking for the presence of the bacteria associated with periodontal disease, as well as measuring various biological indicators of bacterial exposure. They found that individuals with periodontal disease whose biomarkers showed increased bacterial exposure were more likely to develop coronary heart disease or atherogenesis (plaque formation in the arteries).
“While more research is needed to better understand the connection between periodontal disease and cardiovascular disease, this study suggests the importance of taking care of your teeth and gums and how that can help you take care of your heart,” said Susan Karabin, President of the American Academy of Periodontology (AAP). “With the number of people with heart disease continuing to increase, it is important to understand that simple activities like brushing and flossing twice a day, and regular visits to your dental professional can help lower your risk of other health conditions.”
The results of the study have been published in the Journal of Periodontology, the official publication of the AAP.
Source: Beck JD, Couper DJ, Falkner KL et al. The Periodontitis and Vascular Events (PAVE) Pilot Study: Adverse Events. J. Periodontol. 79(1), 90–96 (2008).
Study reveals insight into the origins of sudden cardiac death
Approximately 300,000 Americans die every year without apparent warning as a result of an electrical “storm” of activity that arises within their heart muscle, leading the heart to cease beating. The rhythm disturbance thought to result in these sudden cardiac deaths is known as ventricular fibrillation (VF), but why this electrical disturbance should occur in one person and not another is not fully understood.
A collaboration of researchers from the USA, Canada and Spain – the majority based at a research laboratory at the University of Michigan Medical School – have revealed some important clues to the mystery as well as the ability to translate animal research to humans. José Jalife, Senior Author, describes the electrical storm of VF as a hurricane or tornado that disrupts the regular rhythm of the heart’s electrical activity.
The research demonstrated that the turbulence that arises in the electrical storm is organized into spiral vortices, and this is consistent regardless of the species of mammal involved. These vortices, also called rotors, prevent the heart’s chambers from pumping in sync – essential for normal heart function.
The discovery that the rate of fibrillation changes according to body size is exciting, not only because it brings new and interesting knowledge from the point of view of evolutionary biology, but most important because it erases previous concerns in science about the relevance of studies in small animals like mice to understanding the most lethal cardiac arrhythmia in people,” says Jalife.
Jalife and colleagues will continue their research, as there are many questions that remain unanswered and new screening and treatment options may be years away. The team are also investigating the membrane ion channels of heart cells – gene mutations in the proteins of which may predispose to VF, particually in individuals who have experienced previous heart problems, such as heart attack, leaving damaged tissue.
Other investigations include the development of mathematical modelling software that could map electrical activity in human hearts, based on electrode input. The aim is to eventually be able to provide therapy targeted to specific areas of the heart where an abnormal rhythm may occur.
The study was published in Proceedings of the National Academy of Sciences.
Sources: www.med.umich.edu Noujaim SF, Berenfeld O, Kalifa J et al. Universal scaling law of electrical turbulence in the mammalian heart. Proc. Natl Acad. Sci. USA 104(52), 20985–20989 (2007).
Anxiety may up heart attack risk by up to 40%
It is well known that people with the so-called Type A personality – people who possess traits including being highly competitive, aggressive and incapable of relaxation – are more likely to suffer a heart attack. However, new research indicates that individuals who are nervous and more socially withdrawn may also have reason for concern.
“What we’re seeing is over and beyond what can be explained by blood pressure, obesity, cholesterol, age, cigarette smoking, blood sugar levels and other cardiovascular risk factors,” said Biing-Jiun Shen, an Assistant Professor of Psychology at the University of Southern California in Los Angeles.
The effect of anxiety in increasing heart attack risk is more than the effects of depression, anger, hostility, Type A behavior and other negative emotions. “These psychological factors are important in predicting the risk of heart disease, but anxiety is unique,” Shen said. “Older men with sustained and pervasive anxiety appear to be at increased risk for a heart attack even after their levels of depression, anger, hostility and Type A behavior are considered.”
Shen and colleagues analyzed data from the Normative Aging Study, which was designed to assess medical and psychological changes associated with aging among a group of initially healthy men. Each of the 735 men participating in the new analysis completed psychological testing in 1986 and was in good cardiovascular health at the time.
Four different measures of anxiety were used in the study. The first anxiety scale measured psychasthenia, or excessive doubts, obsessive thoughts and irrational compulsions. The second, measured social introversion, or anxiety, insecurity and discomfort in interpersonal and social situations. The third, measured phobias, or excessive anxieties or fears about animals, situations or objects. Finally the fourth scale measured manifest anxiety – the tendency to experience tension and physical arousal in stressful situations.
Study participants also completed questionnaires regarding their health habits such as smoking, alcohol consumption and daily diet, and had a medical examination every 3 years over a follow-up period that averaged more than 12 years.
Men who tested at the highest 15th percentile on any of the four scales, as well as on a scale combining all four, faced an increase in the risk of heart attack of approximately 30–40%. Those who were found to have even higher levels of anxiety on psychological testing faced an even higher risk of heart attack. This finding held true even after the findings were adjusted for standard cardiovascular risk factors, health habits and negative psychological and personality traits.
“The good thing about anxiety is that it’s very treatable,” said Shen. He continued, “If someone is highly anxious – if they’re suffering from panic attacks or social phobia or constant worry – we recommend therapy. Although more research is needed, we hope that by reducing anxiety, we can lower the future risk of heart attack. This is one more reason to seek help.”
The research has been published in the January 15, 2008, issue of the Journal of the American College of Cardiology (JACC).
Source: Shen BJ, Avivi YE, Todaro JF et al. Anxiety characteristics independently and prospectively predict myocardial infarction in men the unique contribution of anxiety among psychologic factors. J. Am. Coll. Cardiol. 51, 113–119 (2008)