@article {6992, title = {Consumption of Caffeinated Products and Cardiac Ectopy.}, journal = {J Am Heart Assoc}, volume = {5}, year = {2016}, month = {2016 Jan}, abstract = {

BACKGROUND: Premature cardiac contractions are associated with increased morbidity and mortality. Though experts associate premature atrial contractions (PACs) and premature ventricular contractions (PVCs) with caffeine, there are no data to support this relationship in the general population. As certain caffeinated products may have cardiovascular benefits, recommendations against them may be detrimental.

METHODS AND RESULTS: We studied Cardiovascular Health Study participants with a baseline food frequency assessment, 24-hour ambulatory electrocardiography (Holter) monitoring, and without persistent atrial fibrillation. Frequencies of habitual coffee, tea, and chocolate consumption were assessed using a picture-sort food frequency survey. The main outcomes were PACs/h and PVCs/hour. Among 1388 participants (46\% male, mean age 72 years), 840 (61\%) consumed >=1 caffeinated product per day. The median numbers of PACs and PVCs/h and interquartile ranges were 3 (1-12) and 1 (0-7), respectively. There were no differences in the number of PACs or PVCs/h across levels of coffee, tea, and chocolate consumption. After adjustment for potential confounders, more frequent consumption of these products was not associated with ectopy. In examining combined dietary intake of coffee, tea, and chocolate as a continuous measure, no relationships were observed after multivariable adjustment: 0.48\% fewer PACs/h (95\% CI -4.60 to 3.64) and 2.87\% fewer PVCs/h (95\% CI -8.18 to 2.43) per 1-serving/week increase in consumption.

CONCLUSIONS: In the largest study to evaluate dietary patterns and quantify cardiac ectopy using 24-hour Holter monitoring, we found no relationship between chronic consumption of caffeinated products and ectopy.

}, issn = {2047-9980}, doi = {10.1161/JAHA.115.002503}, author = {Dixit, Shalini and Stein, Phyllis K and Dewland, Thomas A and Dukes, Jonathan W and Vittinghoff, Eric and Heckbert, Susan R and Marcus, Gregory M} } @article {7787, title = {Sleep characteristics that predict atrial fibrillation.}, journal = {Heart Rhythm}, volume = {15}, year = {2018}, month = {2018 Sep}, pages = {1289-1295}, abstract = {

BACKGROUND: The relationship between sleep disruption, independent of obstructive sleep apnea (OSA), and atrial fibrillation (AF) is unknown.

OBJECTIVE: The purpose of this study was to determine whether poor sleep itself is a risk factor for AF.

METHODS: We first performed an analysis of participants in the Health eHeart Study and validated those findings in the longitudinal Cardiovascular Health Study, including a subset of patients undergoing polysomnography. To determine whether the observed relationships readily translated to medical practice, we examined 2005-2009 data from the California Healthcare Cost and Utilization Project.

RESULTS: Among 4553 Health eHeart participants, the 526 with AF exhibited more frequent nighttime awakening (odd ratio [OR] 1.47; 95\% confidence interval [CI] 1.14-1.89; P = .003). In 5703 Cardiovascular Health Study participants followed for a median 11.6 years, frequent nighttime awakening predicted a 33\% greater risk of AF (hazard ratio [HR] 1.33; 95\% CI 1.17-1.51; P <.001). In patients with polysomnography (N = 1127), every standard deviation percentage decrease in rapid eye movement (REM) sleep was associated with a 18\% higher risk of developing AF (HR 1.18; 95\% CI 1.00-1.38; P = .047). Among 14,330,651 California residents followed for a median 3.9 years, an insomnia diagnosis predicted a 36\% increased risk of new AF (HR 1.36; 95\% CI 1.30-1.42; P <.001).

CONCLUSION: Sleep disruption consistently predicted AF before and after adjustment for OSA and other potential confounders across several different populations. Sleep quality itself may be important in the pathogenesis of AF, potentially representing a novel target for prevention.

}, issn = {1556-3871}, doi = {10.1016/j.hrthm.2018.05.008}, author = {Christensen, Matthew A and Dixit, Shalini and Dewland, Thomas A and Whitman, Isaac R and Nah, Gregory and Vittinghoff, Eric and Mukamal, Kenneth J and Redline, Susan and Robbins, John A and Newman, Anne B and Patel, Sanjay R and Magnani, Jared W and Psaty, Bruce M and Olgin, Jeffrey E and Pletcher, Mark J and Heckbert, Susan R and Marcus, Gregory M} } @article {7971, title = {Alcohol consumption and leukocyte telomere length.}, journal = {Sci Rep}, volume = {9}, year = {2019}, month = {2019 Feb 05}, pages = {1404}, abstract = {

The relationship between alcohol consumption and mortality generally exhibits a U-shaped curve. The longevity observed with moderate alcohol consumption may be explained by other confounding factors, and, if such a relationship is present, the mechanism is not well understood. Indeed, the optimal amount of alcohol consumption for health has yet to be determined. Leukocyte telomere length is an emerging quantifiable marker of biological age and health, and a shorter telomere length is a predictor of increased mortality. Because leukocyte telomere length is a quantifiable and objectively measurable biomarker of aging, we sought to identify the amount of alcohol consumption associated with the longest telomere length and least telomere length attrition. Among over 2,000 participants from two distinct cohort studies, we found no pattern of alcohol consumption that was associated with longer telomere length or less telomere length attrition over time. Binge drinking may reduce telomere length. Using telomere length as a marker of age and health, these data fail to demonstrate any benefits of alcohol consumption, even when consumed in moderation.

}, issn = {2045-2322}, doi = {10.1038/s41598-019-38904-0}, author = {Dixit, Shalini and Whooley, Mary A and Vittinghoff, Eric and Roberts, Jason D and Heckbert, Susan R and Fitzpatrick, Annette L and Lin, Jue and Leung, Cindy and Mukamal, Kenneth J and Marcus, Gregory M} }