The present study included 15,486 patients from 39 countries within the STABILITY trial of darapladib. Their mean age was 65 years, 18 percent were women, mean BMI was 28, and 35 percent participated in cardiac rehab. Based on the self-reported International Physical Activity Questionnaire, the patients were allocated to tertiles of activity: mild (<3 metabolic equivalents [METS]), moderate (3-6 METS) and vigorous (>6 METS). Patients were also queried about their level of activity at work and during leisure time.

Over the 3.7 years of follow-up, the unadjusted and adjusted analyses showed a greater reduction in the primary outcome of all-cause mortality with moderate and vigorous levels of physical activity vs. mild (adjusted hazard ratio [HR], 0.75 and 0.70, respectively). Likewise, the reductions were greater with moderate and vigorous activity vs. mild activity for cardiovascular death (adjusted HR, 0.89 and 0.71, respectively) and non-cardiovascular death (adjusted HR, 0.54 and 0.73, respectively).

Major adverse coronary events were lower with vigorous activity vs. mild activity (adjusted HR, 0.81), but similar with moderate activity (adjusted HR, 0.96).

No difference was seen for myocardial infarction and stroke between the groups.

The investigators found that a doubling of the exercise volume and of the exercise duration also produced reductions in all-cause and cardiovascular mortality. And a one-level increase in average exercise intensity was associated with a reduction in total mortality (adjusted HR, 0.84) and cardiovascular mortality (adjusted HR, 0.81).

“At a population level, the greatest benefits to health are likely to be achieved by modest increases in exercise in sedentary persons, especially in persons who have a higher risk of adverse events, and those with exertional angina and dyspnea,” the authors write.

In an accompanying editorial comment, Thijs M.H. Eijsvogels, PhD, and Martijn F.H. Maessen, PhD, note the data from this study suggest that a 33 percent reduction in all-cause mortality can be achieved with as little as 10 minutes of walking a day at a brisk pace (3.5 mph) or with 15-20 minutes of walking at a slower pace of 2-2.5 mph. “The low volume of this minimal effective dose may stimulate patients to incorporate feasible physical activity goals in their daily lives and may also eliminate barriers, such as insufficient time or self-confidence, to become physically active,” they write. They also state, as do the study authors, that the findings in this study require confirmation in randomized, clinical trials.

Eijsvogels and Maessen conclude that in the meantime, for secondary prevention, patients and clinicians should remember that when it comes to exercise, “a little is good, more is better, and vigorous is best.”

Stewart RAH, Held C, Hadziosmanovic N, et al. J Am Coll Cardiol 2017;70:1689-1700.

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The incidence of ischemic stroke was 4.1 percent in the overall study cohort and was 12.2 percent among patients with a previous cerebral or intracranial hemorrhage. Hemorrhagic stroke was almost as common as ischemic stroke in this population. The incidence of ischemic stroke increased with increasing CHADS₂ or CHADS₂-VASc scores in the overall study population (p < 0.001) and was consistent with current reference rates for a general population of AFib patients. The risk of major bleeding also increased with increasing CHADS₂-VASc scores and was considerably higher than in an OAC-treated general population of AFib patients.

“Our data show that this subset of patients would benefit greatly from alternative methods of stroke prevention that do not impose an increased bleeding risk,” the authors write.

Redfors B, Gray WA, Lee RJ, et al. JACC: Clin Electrophysiol 2017;Sept 27:[Epub ahead of print].

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In exploring the relation of left atrial (LA) remodeling and altered LA function to AFib in obesity, the authors note LA enlargement to be present in nearly all obese patients in postmortem studies. Previous studies also found LA size to be an independent predictor of AFib, and obesity to be more a potent predictor of LA enlargement than hypertension.

Regarding the relation between fat and AFib, multiple controlled studies demonstrated an association between pericardial fat and AFib; however, fat deposits in direct contact with LA myocardium (EAT) have shown a higher likeliness in the development of AFib. Meanwhile, studies have associated obesity with increased pericardial fat volumes. “In summary, the paracrine effects of excessive fat (particularly EAT) in obese patients, in association with modulation of the autonomic nervous system may serve as triggers for the development of AF[ib] and contribute to its severity,” the authors write.

In recent epidemiological studies, obesity has emerged as an independent risk factor for AFib.

The authors also highlight the complexity of pathophysiological mechanisms linking obesity and AFib, emphasizing they are not yet completely understood. These mechanisms include dysregulation in domains such as hemodynamics, neurohumoral, inflammatory, metabolic, adipokines and autonomics, and a combination of these mechanisms ultimately contribute to the initiation and maintenance of AFib in obese atria.

“Although future studies are needed to determine the clinical relevance of this phenomenon, the current evidence from weight-loss intervention studies … argue that the obesity paradox should not be used as a rationale against aggressive lifestyle risk factor modification, including weight loss for management of AF[ib] patients,” they write.

Specifically, while weight gain is associated with increased risk of AFib, intentional weight loss results in a favorable impact on the epidemiology of AFib, reducing symptom burden and severity, EAT, and LA volumes and left ventricular wall thickness. The authors suggest conducting future studies to determine if these strategies can decrease the long-term risk of mortality, stroke and heart failure hospitalization.

Higher CRF levels have also been associated with greater arrhythmia-free survival in patients with existing AFib, as well as a lower risk of AFib recurrence and symptom burden. Aerobic interval training also was found to significantly lower AFib burden over a short-term follow-up period.

“Future large randomized controlled trials are needed to determine if the beneficial effects of exercise in AF[ib] patients in the short-term may translate into favorable CVD outcomes in the long-term follow-up,” the authors conclude.

Lavie CJ, Pandey A, Lau DH, et al. J Am Coll Cardiol 2017;70:2022-35.

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Atherosclerosis was observed more frequently among participants who skipped breakfast and was also higher in participants who consumed low-energy breakfasts compared with breakfast consumers. Additionally, cardiometabolic risk markers were more prevalent in those who skipped breakfast and low-energy breakfast consumers compared with breakfast consumers. Participants who skipped breakfast had the greatest waist circumference, body mass index, blood pressure, blood lipids and fasting glucose levels.

Participants who skipped breakfast were more likely to have an overall unhealthy lifestyle, including poor overall diet, frequent alcohol consumption and smoking. They were also more likely to be hypertensive and overweight or obese. In the case of obesity, the study authors said reverse causation cannot be ruled out, and the observed results may be explained by obese patients skipping breakfast to lose weight.

In an accompanying editorial, Prakash Deedwania, MD, FACC, writes this study provides clinically important information by demonstrating the evidence of subclinical atherosclerosis in people who skip breakfast.

“Between 20 and 30 percent of adults skip breakfast and these trends mirror the increasing prevalence of obesity and associated cardiometabolic abnormalities,” Deedwania says. “Poor dietary choices are generally made relatively early in life and, if remained unchanged, can lead to clinical cardiovascular disease later on. Adverse effects of skipping breakfast can be seen early in childhood in the form of childhood obesity and although breakfast skippers are generally attempting to lose weight, they often end up eating more and unhealthy foods later in the day. Skipping breakfast can cause hormonal imbalances and alter circadian rhythms. That breakfast is the most important meal of the day has been proven right in light of this evidence.”

Uzhova I, Fuster V, Fernández-Ortiz A, et al. J Am Coll Cardiol 2017;70:1833-42.

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Results showed that reducing sodium (from high to low) was associated with mean SBP differences of –3.20, –8.56, –8.99 and –7.04 mm Hg, respectively, across the baseline SBP strata for participants in the control diet group, while the DASH diet was associated with mean SBP differences of –4.5, –4.3, –4.7 and –10.6 mm Hg, respectively. The combined effects of the low sodium-DASH diet vs. the high sodium-control diet on SBP were –5.3, –7.5, –9.7 and –20.8 mm Hg, respectively.

“These findings demonstrate that the individual and combined effects from both sodium reduction and the DASH diet are profound particularly in hypertensive persons with higher BP,” researchers said. They also noted that SBP reductions in adults with the highest levels of SBP (≥150 mm Hg) “were striking and reinforce the importance of both sodium reduction and the DASH diet in this high-risk group.”

The study did have limitations, including that adults with chronic kidney disease, medication-treated hypertension, medication-treated diabetes, and heart failure were excluded from participation. “Future studies should determine the magnitude of BP reduction that can be achieved in patients with more severe hypertension and in those with heart failure and kidney disease,” they write.

Their findings have clinical and public health implications, the authors write, showing that most adults with uncontrolled BP can experience substantial reductions in SBP from dietary changes alone, reinforcing the importance of lifestyle interventions in the management of hypertension.

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Results showed an increase in prevalence of U.S. adults with hypertension under the new guidelines, compared with the JNC 7 guideline published in 2003 (45.6 percent vs. 31.9 percent, respectively). Overall, 103.3 million U.S. adults would have hypertension under the 2017 ACC/AHA guideline, of whom 81.9 million would be recommended antihypertensive medication.

“Implementation of the 2017 ACC/AHA Hypertension Guidelines has the potential to increase the prevalence of hypertension and use of antihypertensive medication among U.S. adults,” the authors write. “This should translate into a reduction in cardiovascular disease events.” Additionally, the authors note the new guideline has the potential to “increase hypertension awareness, encourage lifestyle modification and focus antihypertensive medication initiation and intensification on U.S. adults with high CVD risk.”

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