ACC.11 60th Annual Scientific Session & Expo

New Orleans, LA; April 2-5, 2011

Two Studies Indicate Greater Cardiovascular Benefits From Regular Exercise In Elderly Women

New Orleans, LA—Although regular physical activity has been associated with a decreased risk of cardiovascular disease, reduced in-hospital mortality rates, and improved short-term prognosis in male and female patients with acute coronary syndrome (ACS), two Greek studies presented at the ACC.11 meeting found that women reap the greatest benefits from it. The first study, led by Panagiotis G. Aggelopoulos, First Cardiology Clinic, University of Athens School of Medicine, Greece, sought to determine whether differed between in the relationship between physical activity status, the development of left ventricular systolic dysfunction (LVSD), and inflammatory response in male and female patients 65 years of age and older who had been hospitalized for ACS between 2006 and 2009. The study, which included 492 consecutive elderly patients, used logistic regression models to assess the impact of regular physical activity status on the development of LVSD, as evaluated by echocardiography on day 5 of hospitalization, and inflammatory response at entry. The investigators found that 46% of women who developed LVSD were physically inactive as compared with 20% of the other female participants (P = .02). They also found a significant positive association between physical activity levels and ejection fraction in female subjects (P = .03, one-tailed), but not in male subjects (P = .15, one-tailed), and a 76% lower odds of developing systolic dysfunction among women who were physically active as compared with their sedentary counterparts. Based on these findings, Aggelopoulos and colleagues conclude “Long-term enrollment to a physical active lifestyle seems to confer further cardioprotection by reducing inflammatory response and preserving left ventricular systolic function in elderly female but not in male patients with an ACS.” The second study, led by Evangelos Oikonomou, First Cardiology Clinic, Hippokration Hospital, University of Athens School of Medicine, Greece, assessed the impact of regular physical activity on QTc duration in a sample of middle-aged and elderly residents (age, 52-78 years) of Ikaria Island in Greece. Inhabitants of Ikaria Island are known to have high rates of longevity and low cardiovascular mortality rates. The study included a total of 1071 residents, of whom 47% were men. Oikonomou and colleagues found that the QTc was significantly shorter in women who had vigorous or moderate physical activity levels, with a QTc of 408±2 msec and 411±1 msec, respectively, as compared with a QTc of 419±2 msec in women who had low physical activity levels. Men who had vigorous or moderate physical activity levels had a similar QTc similar to men who had low physical activity levels, with a QTc of 395±2 msec, 402±2 msec, and 402±3 msec found in each of these groups, respectively. Using linear regression analysis, the investigators found that physical activity level was significantly associated with shorter QTc in women even after adjusting for age, body mass index, diet, and a variety of medical and social history factors; no such association was observed in men. In addition, women with a moderate level of physical activity and those with a vigorous level of physical activity were 70% and 80% less likely, respectively, than women with a low level of physical activity to have a QTc interval >450 msec. Oikonomou and colleagues conclude that their findings indicate “gender differences in the cardioprotective effect of habitual exercise,” at least as far as the population of Ikaria Island are concerned.

Life Prolongation From ICD Therapy Minimal in the Elderly

New Orleans, LA—Implantable cardioverter defibrillators (ICDs) have demonstrated clear life-saving benefits for persons who are at high risk of sudden cardiac death. However, a poster presented at the ACC.11 meeting by researchers from Leiden University Medical Center in the Netherlands revealed that elderly patients have significantly less life prolongation from this intervention as compared with younger patients, despite ICDs and shocks generally being administered appropriately in this population. “The current guidelines for ICD treatment are based on the findings of large, randomized clinical trials. However, these trials often included an upper age limit and comprised relatively healthy patients. Therefore, validation of these guidelines in routine clinical practice is essential,” said Johannes B. van Rees, MD, lead researcher of the study, in an interview with Annals of Long-Term Care: Clinical Care and Aging. The retrospective study included a total of 1395 patients who received an ICD between 1996 and 2009 at Leiden University Medical Center to protect against sudden cardiac death; these patients had no congenital structural or monogenetic heart disease. Patients were divided into 3 groups based on their age: <65 years (n = 705; mean age, 54±9 years); 65 to 74 years (n = 493; mean age, 69±3 years); and ³75 years (n = 197; mean age, 78±3 years). All-cause mortality, appropriate ICD therapy, and appropriate ICD shocks were the study end points. Researchers found no statistically significant difference in the cumulative incidence of appropriate therapy between the 3 age groups or in the cumulative incidence of appropriate shocks; however, 1 year following appropriate therapy or shock, older patients had a significantly higher mortality rate than their younger counterparts. The cumulative incidences of mortality 1 year after appropriate therapy was 5% for patients younger than 65 years (95% confidence interval [CI], 2%-9%), 12% for patients 65 to 74 years (95% CI, 6%-18%), and 22% for patients 75 years and older (95% CI, 6%-38%). The cumulative incidences of mortality 1 year after appropriate shock was 7% for patients younger than 65 years (95% CI, 2%-13%), 21% for patients 65 to 74 years (95% CI, 9%-32%), and 35% for patients 75 years and older (95% CI, 10%-60%). “Since this is the first retrospective study reporting on a decreased life prolongation of prophylactic ICD treatment in the elderly, additional studies are warranted for validation,” van Rees said. “Consequently, it is too early to conclude that elderly patients do not benefit from ICD treatment at all, but we feel that, based on our results, elderly cardiac patients deserve more attention in the future guidelines for prophylactic ICD treatment.”

Several study investigators received research grants from St Jude, Medtronic, Boston Scientific, and Biotronik.

Interview: Is Orthostatic Hypotension Associated With Incident Heart Failure?

During the ACC.11 meeting, Ravi V. Desai, MD, Lehigh Valley Hospital, Allentown, PA, and colleagues presented the results of a retrospective study that assessed whether orthostatic hypotension could serve as a predictor of incident heart failure in elderly community-dwelling individuals; the study was titled “Orthostatic Hypotension: A New Risk Factor for Incident Heart Failure in Community-Dwelling Older Adults.” Annals of Long-Term Care had the opportunity to discuss this topic and the study findings with Dr. Desai.

How common is orthostatic hypotension among elderly individuals, including in long-term care residents?

It is quite common. In this study of close to 6000 community-dwelling older adults, it was present in about 20% of the enrolled subjects. In other studies, it has been reported to occur in 5% to 30% of healthy elderly individuals. However, in long-term care residents, a population where polypharmacy and comorbidities are common, it may be even more prevalent.

What are some of the problems associated with orthostatic hypotension?

It may be completely asymptomatic, as only about 1 in 5 individuals may have symptoms such as dizziness and frequent falls, but it is important to assess for it routinely, as it has been associated with myocardial infarction, all-cause mortality, and, in our study, incident heart failure.

Can you tell us about how your study was conducted?

The study used data from the NHLBI [National Heart, Lung and Blood Institute]-sponsored Cardiovascular Health Study (CHS), which enrolled nearly 6000 community-dwelling older adults who were well characterized at baseline with all common and emerging cardiovascular risk factors. These subjects were followed up for over 13 years for common cardiovascular end points, such as myocardial infarction, heart failure, peripheral vascular disease, stroke, and transient ischemic attack. Moreover, these end points were centrally adjudicated by consensus opinion by an expert committee. We used a propensity-matched observational study design to assemble a balanced cohort of those with and without orthostatic hypotension and studied the effect of baseline orthostatic hypotension in that balanced cohort.

What were the study findings?

We found that orthostatic hypotension was independently associated with incident heart failure in the aforementioned propensity-matched cohort.

Are further studies warranted?

I think it is an important finding that should be replicated in other populations, including long-term care residents.

Is there a take-home message that you would share with healthcare providers?

Orthostatic hypotension should not be overlooked as it is an easy-to-measure and noninvasive marker for cardiovascular morbidity and mortality in older adults.

Ali Ahmed, MD, one of the study’s lead investigators, is supported by the National Institutes of Health through grants (R01-HL085561 and R01-HL097047) from the National Heart, Lung, and Blood Institute and by a generous gift from Ms. Jean B. Morris of Birmingham, AL.

Low HDL Cholesterol Levels Predict Long-Term Mortality In Older Adults With Acute MI

New Orleans, LA—Low high-density lipoprotein (HDL) cholesterol, which is a potent risk factor for developing atherosclerosis, is often encountered in patients with acute coronary syndrome; however, the prognostic significance of this finding following non-ST segment elevation acute myocardial infarction (NSTE AMI) has been unclear. At the ACC.11 meeting, Danielle Duffy, MD, Jefferson Heart Institute, Philadelphia, PA, and colleagues shed light on the issue through their examination of clinical data from the CRUSADE (Can Rapid Risk Stratification of Unstable Angina Patients Suppress Adverse Outcomes with Early Implementation of the ACC/AHA Guidelines) National Quality Improvement database that were linked to Medicare files. The study reviewed clinical data for 24,805 patients who were enrolled at 434 CRUSADE-participating hospitals between February 15, 2003, and December 30, 2006. Of these patients, 50% had low HDL cholesterol levels (² 40 mg/dL) and 18% had very low HDL cholesterol levels (² 30 mg/dL). After a median follow-up of 2.9 years, the overall mortality rate was 39.5%. Adjusting for traditional cardiovascular risk factors, known history of cardiovascular disease, and severity of NSTE AMI presentation revealed an 11% increased risk of death in patients with very low HDL cholesterol levels, as compared with patients with normal HDL cholesterol levels, a finding that reached statistical significance (P = .0003). When modeled as a continuous variable, the investigators found that long-term mortality was increased by 5% for every 5 mg/dL decrease in HDL cholesterol below 40 mg/dL. Because low HDL cholesterol levels at the time of NSTE AMI predicted increased long-term mortality, even after numerous confounding risk factors were accounted for, the investigators conclude that “targeting HDL to lower residual risk is a strategy that holds promise for cardiovascular event reduction” following NSTE AMI in older adults with low HDL cholesterol levels.

CRUSADE is a national quality improvement initiative of the Duke Clinical Research Institute and was funded by Schering-Plough Corporation. Additional funding support was provided by Bristol-Myers Squibb/Sanofi-Aventis Pharmaceuticals Partnership.