Researchers from the University of Pennsylvania School of Medicine analyzed the health outcomes and costs of implantable cardioverter-defibrillators (ICDs) in 14,250 nationally representative patients aged 66 years or older. Data were taken from the Medicare database of patients who had received an ICD as primary-prevention treatment for congestive heart failure (CHF) at over 200 hospitals in the USA between October 2003 and September 2005. In total, 7125 ICD recipients and 7125 controls were analyzed.
As one of the first studies to use data from the ‘real world’ as opposed to an experimental setting, the results demonstrated impressive reductions in the morbidity rate for patients fitted with an ICD as the primary treatment for CHF. On average, patients with an ICD had a 38% lower mortality rate compared with those without. First-year mortality was 13% in those who received ICDs compared with 23% in those who did not. In the second year, the mortality rate increased to 17% in the ICD group and 29% in those receiving alternative therapies.
The healthcare costs of the treatment were also evaluated. Similar to cost estimates from previous clinical studies, the initial cost (within the first 30 days) of fitting a patient with an ICD is approximately US$42,000 more than alternative therapies for CHF (median difference: US$41,542; p < 0.001). At 6 months, the physician and outpatient costs of ICD use were approximately US$1800 more for ICD-treated patients than alternatives (median difference: US$1828; p < 0.001). These results are comparable with those from cost–effectiveness models, which found ICD use to be cost effective.
“This study confirms, through real-world experience among thousands of patients, what clinical trials among hundreds of patients found, which is that ICDs enable patients to live longer, at a reasonable cost to society,” said Peter Groeneveld (University of Pennsylvania School of Medicine). “The findings show that the overall economic value delivered by the ICD is acceptable by US standards for healthcare expenditures, further substantiating Medicare’s decision to expand coverage of ICDs for primary-prevention patients.”
Source: Groeneveld PW, Farmer SA, Suh JJ, Yang F, Matta MA. Outcomes and costs of implantable cardioverter-defibrillators for primary prevention of sudden cardiac death among the elderly. Heart Rhythm doi:10.1016/j.hrthm.2008.01.038 (2008).
Heart attack symptoms should prompt immediate action
A recent study from the Mayo Clinic (MN, USA) supports recommendations from the American Heart Association, and the British Heart Foundation, that people experiencing heart attack symptoms for 5 min should seek emergency medical care.
In an analysis of more than 440,000 heart attack incidents, researchers found that patients who arrived at hospital soon after the onset of heart attack symptoms were more likely to receive appropriate medical treatment. Of the patients who arrived at hospital 1–2 h after the onset of symptoms, 77% received reperfusion therapy compared with 73 and 46% of those who arrived 2–3 and 10–12 h after symptom onset, respectively.
The most common indicators of a heart attack are not always recognized by patients. The British Heart Foundation has relaunched a previous initiative, the Doubt Kills campaign, to encourage people to respond to heart attack symptoms by calling emergency services. Fear of embarrassment if the condition turns out not to be serious can also cause people to delay seeking medical assistance. The campaign features posters on buses and billboards, and press and radio advertising. A separate but related campaign targeting South Asian audiences in particular will run concurrently.
As Henry Ting (Mayo Clinic), one of the study researchers, commented: “Does coming to the hospital earlier improve your chances of surviving a heart attack? The answer is an emphatic yes,”
It is hoped that the current British Heart Foundation campaign and other similar efforts will disseminate this information to those who are most at risk.
Sources: No authors listed. Delay in reaching hospital after a heart attack starts affects survival. Mayo Clin. Womens Healthsource 12(5), 3 (2008). British Heart Foundation www.bhf.org.uk.
Cilostazol: a potential alternative to aspirin for preventing recurrent stroke
Drug: Cilostazol
Tradename: Pletal®
Manufacturer: Otsuka America Pharmaceutical, Inc.
Trial: Pilot study
Indication: Prevention of recurrent stroke
Results from a randomized pilot trial in China show that cilostazol, a phosphodiesterase 3 inhibitor, may be as effective as aspirin in preventing recurrent stroke.
Following a stroke, most patients are treated with aspirin to reduce their risk of a further stroke. However, aspirin use is associated with cerebral bleeding. Following a previous study in Japan that found cilostazol to be effective in reducing the risk of ischemic stroke, a recent study, published in Lancet Neurology, has investigated the safety and efficacy of cilostazol as an alternative to aspirin as post-stroke medication.
“Aspirin-related cerebral hemorrhage is a complication that is of concern, particularly in China, where there is a high incidence of cerebral hemorrhage in secondary-prevention programs and within the community,” the study authors write.
The drug has a different mechanism of action to aspirin; it prevents inactivation of cAMP and irreversibly inhibits platelet aggregation and vasodilation. Cilostazol is currently approved by the US FDA for the treatment of claudication associated with peripheral vascular disease.
The multicenter, double-blind study enrolled 720 patients who had experienced an ischemic stroke in the last 1–6 months (mean age: 60.2 years). Participants were randomly assigned to receive either cilostazol (n = 360) or aspirin (n = 360) for 12–18 months. The primary end point was any recurrent stroke (ischemic, hemorrhagic or subarachnoid). Over the study period, 12 of the cilostazol-treated patients and 20 of the aspirin-treated group experienced a stroke. Bleeding events in the brain were also significantly more common in the aspirin-treated group than the cilostazol group (7 vs 1; p = 0.034).
The study authors and Graeme Hankey (Royal Perth Hospital, Australia), in an accompanying article, urge caution when interpreting the results of the trial. Owing to the small number of patients and short follow-up duration, a Phase III randomized, controlled trial into the comparable safety and efficacy of aspirin and cilostazol is required to draw more definitive conclusions.
“The implications of these results for clinicians are that they offer hope for a safer antiplatelet drug that is at least as effective as aspirin for use in patients with ischemic stroke,” Hankey commented. “The implications of these results for researchers are the need to explore the external validity of these pilot study results in a Phase 3 randomized trial that compares cilostazol with aspirin … in a large number of high-risk patients with recent ischemic stroke from a wide range of nations and ethnic groups.”
Sources: Huang Y, Cheng Y, Wu J et al.; on behalf of the Cilostazol versus Aspirin for Secondary Ischaemic Stroke Prevention (CASISP) cooperation investigators. Cilostazol as an alternative to aspirin after ischaemic stroke: a randomised, double-blind, pilot study. Lancet Neurol. (Epub ahead of print) (2008); Hankey GJ. Cilostazol shows promise as an alternative to aspirin for patients with ischaemic stroke. Lancet Neurol. (2008) (Epub ahead of print).
Carotid bruits found to be good marker of cardiovascular risk
Carotid bruits are known as an indicator for increased risk of stroke and cerebrovascular events. Christopher A Pickett (Walter Reed Army Medical Center, Washington DC, USA) and colleagues conducted a meta-analysis of literature using the search terms ‘carotid’ and ‘bruit’ on Medline and Embase. Articles that included data on myocardial infarction and cardiovascular death in adults were included in the analysis. In total, 22 articles were included, covering 17,295 patients and 62,431.5 patient-years (median sample size: 273 [range: 38–4736]; median follow-up: 4 years [range: 2–7 years]).
The rate of myocardial infarction was found to be higher in those with carotid bruits than those without (3.69 vs 1.86 per 100 patient-years), as were yearly rates of cardiovascular death (2.85 vs 1.11 per 100 patient-years). Four trials allowed direct comparison of patients with and without bruits; patients with carotid bruit were twice as likely to have a myocardial infarction (odds ratio [OR]: 2.15) and even more likely to die from a cardiovascular-related event (OR: 2.27).
“…the presence of a carotid bruit significantly increased the likelihood of a cardiovascular death or myocardial infarction,” commented Pickett. “Auscultation for carotid bruits in patients at risk for heart disease couple help select those who might benefit the most from an aggressive modification strategy for cardiovascular risk,” the authors conclude.
Source: Pickett CA, Jackson JL, Hemann BA, Atwood JE. Carotid bruit as a prognostic indicator of cardiovascular death and myocardial infarction: a meta-analysis. Lancet 371, 1587–1594 (2008).
Obesity rates and associated cardiovascular risks differ among racial groups in the USA
Published in the Archives of Internal Medicine, further analysis of the multiethnic study on atherosclerosis has found stark differences in the rates of obesity among Chinese–Americans and African–American, Hispanic and white populations. Rates of obesity in the developed world are high and on the increase; across the USA, the percentage of obese men and women, respectively, has increased from 11 and 16% in 1960 to 28 and 34% in 2000.
The multi-ethnic study on atherosclerosis, an observational cohort study, involved 6814 participants aged 45–84 years who did not have cardiovascular disease at baseline (2000–2002). Study participants answered a questionnaire containing questions regarding demographics, health risk factors and current medication, and were tested for a variety of cardiovascular disease markers. Analysis of the data showed that rates of overweight and obesity are much higher in African–Americans, Hispanic and white groups (overweight: 60–85%; obese: 30–50%) than in Chinese–Americans (overweight: 33%; obese: 5%).
“The key finding is that the alarming rates of obesity that we are getting used to seeing are present here… Our metric has changed, society has shifted up to an acceptance level of obesity, but when you bring in the Chinese–Americans, it reminds us that those set points are wrong – obesity is not inevitable,” commented Gregory L Burke (Wake Forest University School of Medicine, NC, USA).
The study also provides additional data that underline the health risks of being overweight or obese. Those who were obese were more likely to have hypertension or diabetes, despite higher use of antihypertensive and antidiabetic medications. Obesity was also associated with the following risk factors for heart disease and stroke: a 17% greater risk of coronary artery calcium; 45% increased risk of common carotid artery intmal medial thickness being greater than the 80th percentile; and 2.7-times greater risk of left ventricular mass greater than the 80th percentile compared with normal body size. Obesity was found to be an independent risk factor for these and associations remained following adjustment for traditional cardiovascular disease risk factors.
Burke commented: “15–20 years ago, people said obesity was not an independent risk factor for heart disease, and when they did that, they basically said that obesity doesn’t matter because all you need to do is treat their hypertension, and if their LDL is high, treat that, and have them not smoke and they’re going to be okay.”
Looking ahead to the wider implications of the study, there is a need to address the obesity epidemic in adults, as well as children. Over recent decades there has been a decrease in cardiovascular disease in many developed countries; however, rising levels of obesity threatens to reverse this trend, placing increasing pressure on healthcare providers.
Source: Burke GL, Bertoni AG, Shea S et al. The impact of obesity on cardiovascular disease risk factors and subclinical vascular disease. The multi-ethnic study of atherosclerosis. Arch. Intern. Med. 168, 928–935 (2008).