Tea for All?
Tea, the serendipitous find of a legendary Chinese emperor >5000 years ago, elevated to an art form in historic Japan and a spark in the American Revolution, perhaps now assumes a new role—protector of hearts.
In this week’s issue of Circulation (Circulation. 2002;105:2476–2481), a team of researchers from Beth Israel Deaconess Medical Center in Boston, Massachusetts General Hospital, and the Harvard School of Public Health, found that patients who reported moderate or heavy tea drinking in the year before suffering an acute myocardial infarction were less likely to die than their non–tea-drinking compatriots.
“In summary, we found that tea consumption is associated with greater survival following acute myocardial infarction,” concluded the researchers, led by Kenneth J. Mukamal, MD, MPH, MA, of Beth Israel. “This finding was consistent for total and cardiovascular mortality and did not change with further adjustment after we controlled for age and sex.” They noted that more controlled studies are needed to confirm these observational findings.
Dr Mukamal and his colleagues performed a prospective cohort study on 1900 patients hospitalized with a confirmed acute myocardial infarction between 1989 and 1994. The patients were part of the Determinants of Myocardial Infarction Onset Study. They analyzed long-term mortality rates of tea consumers. Of the 1900 patients, 1019 consumed no tea, 655 drank <14 cups per week, and 216 drank ≥14 cups of tea each week.
Age- and sex-adjusted mortality was lower among the moderate and heavy tea drinkers than among those who drank no tea. The association was similar for total and cardiovascular mortality.
One reason for the health effect is that tea contains flavonoids and other antioxidants that are hypothesized to have a beneficial health effect. For example, flavonoids might inhibit the oxidation of low-density lipoprotein cholesterol, hindering its ability to clog the coronary arteries.
The authors note, however, that studies of the effects of tea on heart health have been conflicting, leading to the statement that more scientifically controlled trials into the effects of the drink might be helpful in determining its true worth as a heart defender.
A Gene for C-Reactive Protein?
Variations in a single gene are associated with increased blood levels of C-reactive protein, an important risk factor for cardiovascular disease, according to a group of Mayo Clinic researchers who published a study in the May 17 issue of the journal Cytokine (Cytokine. 2002;17:171–174).
The study of the inflammatory processes involved in the development of atherosclerosis is one of the hottest areas of science, and researchers have been delving deeper into finding out how inflammation can lead to devastating strokes and heart attacks. C-reactive protein is a product or marker that indicates inflammation has occurred. It has been linked to interleukin-1 (IL-1), a protein that regulates inflammation, among other processes. It is believed that IL-1 starts the cascade of events that lead to the production of C-reactive protein.
The researchers, led by Peter Berger, MD, of the Mayo Clinic in Rochester, Minnesota, studied the frequency of 4 known polymorphisms of IL-1 genes in 454 patients who were undergoing coronary angiography. They then attempted to determine the influence of these genetic differences on the levels of C-reactive protein and fibrinogen in the plasma.
They found that women and smokers had higher C-reactive protein levels than men. Patients with a genotype called 2.2 for the IL-1B(+3954) polymorphism had levels of C-reactive protein that were twice as high as those of individuals with genotype 1.1 for the same polymorphism. Levels of C-reactive protein were also higher in patients with genotype 1.2 or 2.2 at the IL-1A(+4845) polymorphism. Fibrinogen levels had similar associations with the IL-1 genotypes. These data indicate that IL-1 gene polymorphisms known to affect the inflammatory response are highly related to plasma levels of C-reactive protein and fibrinogen in patients referred for coronary angiography.
“Factors that influence genetic predisposition to disease may enable doctors to identify patients who are most at risk at an earlier age. Furthermore, the growing body of knowledge about markers, such as C-reactive protein, may help physicians in monitoring the onset and progression of disease, as well as the effectiveness of therapeutic interventions,” said Dr Berger.
The study was done in cooperation with researchers from Interleukin Genetics and University of Sheffield (England) and was funded by Interleukin Genetics.
Emergency Physicians Can Deliver Clot-Busters to Stroke Patients Safely, but Will the Patients Get to the Hospital in Time?
Emergency physicians, following the national guidelines, can treat some stroke patients with clot-busting drugs, such as tissue plasminogen activator (tPA,) as quickly and safely as stroke teams, but patients need to get to the hospital within the appropriate window of time.
The study looked at data from 140 patients treated with tPA between 1996 and 2001 by emergency physicians at community, university, and urban teaching hospitals, as well as one community non-teaching hospital. Each of the 4 hospitals adhered to acute stroke treatment guidelines, and all patients were treated by board-certified or board-eligible emergency physicians. The rate of intracranial hemorrhage in treated patients was 7%—the same as in previous studies of tPA use by dedicated stroke teams.
Phillip Scott, MD, Director of the University of Michigan Health System, Emergency Stroke Team, and Assistant Professor in the UM Department of Emergency Medicine, led the retrospective study that was presented May 20, 2002, at the Society for Academic Emergency Medicine St Louis.
However, the numbers of patients eligible for the stroke treatment at the 4 hospitals was too low, indicating that many patients delay going to the hospital after experiencing symptoms. Dr Scott advocated more education of both the public and emergency department teams to reduce the delay.
“Pre-hospital delays are still our biggest problem. This shows us how far we still have to go in educating the public that any sudden change in speech, sensation, or strength might mean they’re having a stroke, and that they must call 9-1-1 and get to the emergency room as quickly as possible,” he said. “And, once they’re there, they should ask the doctor to give them clot-busters, if clot-busters are right for them.”