Long-term alcohol and caffeine intake and risk of sudden cardiac death in women

Alcohol and Arrhythmias

The association between alcohol consumption and abnormalities of heart rate and rhythm has long been recognized. Significant attention has focused on the risk of atrial fibrillation (AF) and sudden cardiac death (SCD) with excessive alcohol intake. Recent studies have advanced our understanding of these relationships and provided additional insights into potentially arrhythmogenic mechanisms. However, considerable uncertainty remains, such as the level of consumption at which harm begins and whether alcohol plays a role in other arrhythmias. This review characterizes the spectrum of conduction abnormalities and heart rhythm disorders in relation to alcohol consumption. In addition, it discusses the latest epidemiologic and experimental evidence, the potential importance of beverage type and constituent ingredients, and conflicting information on drink definitions, thresholds, and recommendations.

Alcohol Consumption and Cardiovascular Health

BACKGROUND

Studies evaluating alcohol consumption and cardiovascular diseases have shown inconsistent results.

METHODS

We performed a systematic review of peer-reviewed publications from an extensive query of Ovid MEDLINE, Ovid Embase, Ovid Cochrane Database of Systematic Reviews, Scopus, and Web of Science from database inception to March 2022 for all studies that reported the association between alcohol consumption in terms of quantity (daily or weekly amounts) and type of beverage (wine, beer or spirit) and cardiovascular disease events.

RESULTS

The study population included a total of 1,579,435 individuals based on 56 cohorts from several countries. We found that moderate wine consumption defined as 1-4 drinks per week was associated with a reduction in risk for cardiovascular mortality when compared with beer or spirits. However, higher risk for cardiovascular disease mortality was typically seen with heavier daily or weekly alcohol consumption across all types of beverages.

CONCLUSIONS

It is possible that the observational studies may overestimate the benefits of alcohol for cardiovascular disease outcomes. Although moderate wine consumption is probably associated with low cardiovascular disease events, there are many confounding factors, in particular, lifestyle, genetic, and socioeconomic associations with wine drinking, which likely explain much of the association with wine and reduced cardiovascular disease events. Further prospective study of alcohol and all-cause mortality, including cancer, is needed.

Coffee and cardiac arrhythmias: Up-date review of the literature and clinical studies

Coffee, next to water, is the most consumed drink in the world. Coffee contains over 1000 chemical compounds, the most popular of which are caffeine, chlorogenic acid, kahweol, cafestol and trigonelline. Numerous studies have shown the beneficial effects of coffee on the cardiovascular system, nervous system, digestive system and kidneys. Due to the high incidence of cardiac arrhythmias, especially atrial fibrillation, the influence of coffee consumption on arrhythmogenesis remains a controversial and clinically important issue. Many mechanisms by which coffee can increase and decrease the risk of arrhythmias have been described. Habitual consumption of moderate amounts of coffee seems to lead to less arrhythmias, which is reflected in the results of many clinical trials and meta-analyzes. This review summarizes the mechanisms of coffee action on the heart muscle and the results of the most recent important clinical trials assessing the impact of coffee consumption on the risk of various cardiac arrhythmias.

Effect of different alcohol consumption levels on the left atrial size: A cross-sectional study in rural China

OBJECTIVE

Previous studies have investigated the relationship between alcohol and ventricular structure; however, few studies have evaluated the relation between alcohol consumption and the atrium size. In this study, we aimed to test the association between alcohol consumption and left atrium (LA) size in the general population.

METHODS

A population-based sample of 10,211 subjects aged ≥35 years and free from hypertension at baseline were followed from January 2012 to August 2013. Left atrial enlargement (LAE) was defined as the ratio of LA diameter to body surface area exceeding 2.4 cm/m2 in both the sexes. Independent factors for LAE were estimated by multiple logistic regression analyses.

RESULTS

The study included 10,211 participants (4,751 men and 5,460 women). Left atrial diameter/body surface area (LAD/BSA) was higher in the moderate and heavy alcohol consumption groups than in the non-drinker group (non-drinker, 20.5±0.03 cm/m2; moderate, 20.8±0.09 cm/m2; and heavy, 20.6±0.06 cm/m2; p<0.001). Both the groups of moderate and heavy drinkers had a higher incidence of LAE than the non-drinker group (6.9% of non-drinkers, 9.9% of moderate drinkers, and 8.4% of heavy drinkers; p<0.001). After adjusting for related risk factors, multiple logistic regression analyses showed that moderate drinkers had an approximately 1.4-fold higher risk of LAE [odds ratio (OR): 1.387, 95% confidence interval (CI) 1.056-1.822, p=0.019] compared with the non-drinkers, and the heavy drinkers had an approximately 1.2-fold higher risk of LAE (OR: 1.229, 95% CI: 1.002-1.508, p=0.047) compared with that of the non-drinkers.

CONCLUSION

Both heavy and moderate drinkers had increased odds for LAE compared with participants with no alcohol consumption in the general population.

[Cardiovascular Risks Associated with the use of Performance-Enhancing Stimulants]

The number of people involved in regular exercise and sports is increasing. Not infrequently, this is associated with intake of sports biologically active food supplements (BAS) and stimulators of physical ability. Data has been reported on the frequency of use of physical ability stimulators among professional athletes and on the use of the most popular food supplements among young people. Special attention is paid to the effect of such use on the cardiovascular system of athletes. This review describes negative cardiac effects and clinical cases of death of athletes due to the use of such supplements and stimulators.

The proarrhythmic conundrum of alcohol intake

The arrhythmogenic potential of alcohol consumption that leads to cardiac arrhythmia development includes the induction of both atrial and ventricular arrhythmias, with atrial fibrillation (AF) being the commonest alcohol-related arrhythmia, even with low/moderate alcohol consumption. Arrhythmias occur both with acute and chronic alcohol use. The "Holiday Heart Syndrome" relates to the occurrence of AF, most commonly following weekend or public holiday binge drinking; however, other arrhythmias may also occur, including other supraventricular arrhythmias, and occasionally even frequent ventricular premature beats and a rare occurrence of ventricular tachycardia. Arrhythmias in individuals with alcohol use disorder, in addition to AF, may comprise ventricular arrhythmias (VAs) that may be potentially fatal leading to cardiac arrest. The effects of alcohol on triggering VAs appear to be dose-dependent, observed more commonly in heavy drinkers, both in healthy individuals and patients with underlying structural heart disease, including ischemic heart disease and alcoholic cardiomyopathy. Men appear to be affected at higher dosages of alcohol, while women can suffer from arrhythmias at lower dosages. On the other hand, low to moderate consumption of alcohol may confer some protection from serious VAs and cardiac arrest (J- or U-curve phenomenon); however, abstinence is the optimal strategy. These issues as they relate to alcohol-induced proarrhythmia are herein reviewed, with the large studies and meta-analyses tabulated and the arrhythmogenic mechanisms pictorially illustrated.

Public health impact of daily life triggers of sudden cardiac death: A systematic review and comparative risk assessment

BACKGROUND

Sudden cardiac death (SCD) may be triggered by daily circumstances and activities such as stressful psycho-emotional events, physical exertion or substance misuse. We calculated population attributable fractions (PAFs) to estimate the public health relevance of daily life triggers of SCD and to compare their population impacts.

METHODS

We searched PubMed, Scopus and the Web of Science citation databases to retrieve studies of triggers of SCD and cardiac arrest that would enable a computation of PAFs. When more studies investigated the same trigger, a meta-analytical pooled risk random-effect estimate was used.

RESULTS

Of the retrieved studies, eight provided data enabling computation of PAFs. The prevalence of exposure within population for SCD triggers in the control periods ranged from 1.06% for influenza infection to 8.73% for recent use of cannabis. Triggers ordered from the highest to the lowest risk increase were: physical exertion, recent cocaine use, episodic alcohol consumption, recent amphetamine use, episodic coffee consumption, psycho-emotional stress within the previous month, influenza infection, and recent cannabis use. The relative risk increase ranged from 1.10 to 4.98. By accounting for both the magnitude of the risk increase and the prevalence in the population, the present estimates of PAF assign 14.5% (95% confidence interval [CI] 4.9-28.5) of all SCDs to episodic alcohol consumption, 9.4% (95% CI 1.2-29.3) to physical exertion, 6.9% (95% CI 0.3-25.0) to cocaine, 6% (95% CI 1.2-14.6) to episodic coffee consumption, 3% (95% CI 0.4-6.8) to psycho-emotional stress in the previous month, 1.7% (95% CI -0.9 to 12.9) to amphetamines, 0.9% (95% CI -4.9 to 12.5) to cannabis, and 0.3% (95% CI 0.2-0.4) to influenza infections.

CONCLUSIONS

In addition to episodic alcohol consumption, a trigger with the greatest public health importance for SCD, episodic physical exertion, cocaine use and coffee consumption also show a considerable population impact.

Relationships between constituents of energy drinks and beating parameters in human induced pluripotent stem cell (iPSC)-Derived cardiomyocytes

Consumption of energy drinks has been associated with adverse cardiovascular effects; however, little is known about the ingredients that may contribute to these effects. We therefore characterized the chemical profiles and in vitro effects of energy drinks and their ingredients on human induced pluripotent stem cell (iPSC)-derived cardiomyocytes, and identified the putative active ingredients using a multivariate prediction model. Energy drinks from 17 widely-available over-the-counter brands were evaluated in this study. The concentrations of six common ingredients (caffeine, taurine, riboflavin, pantothenic acid, adenine, and L-methionine) were quantified by coupling liquid chromatography with a triple quadrupole mass spectrometer for the acquisition of LC-MS/MS spectra. In addition, untargeted analyses for each beverage were performed with a platform combining LC, ion mobility spectrometry and mass spectrometry (LC-IMS-MS) measurements. Approximately 300 features were observed across samples in the untargeted studies, and of these ~100 were identified. In vitro effects of energy drinks and some of their ingredients were then tested in iPSC-derived cardiomyocytes. Data on the beat rate (positive and negative chronotropy), ion channel function (QT prolongation), and cytotoxicity were collected in a dilution series. We found that some of the energy drinks elicited adverse effects on the cardiomyocytes with the most common being an increase in the beat rate, while QT prolongation was also observed at the lowest concentrations. Finally, concentration addition modeling using quantitative data from the 6 common ingredients and multivariate prediction modeling was used to determine potential ingredients responsible for the adverse effects on the cardiomyocytes. These analyses suggested theophylline, adenine, and azelate as possibly contributing to the in vitro effects of energy drinks on QT prolongation in cardiomyocytes.

Dose-Response Relation between Tea Consumption and Risk of Cardiovascular Disease and All-Cause Mortality: A Systematic Review and Meta-Analysis of Population-Based Studies

Tea flavonoids have been suggested to offer potential benefits to cardiovascular health. This review synthesized the evidence on the relation between tea consumption and risks of cardiovascular disease (CVD) and all-cause mortality among generally healthy adults. PubMed, EMBASE, Web of Science, Cochrane Central Register of Controlled Trials, Food Science and Technology Abstracts, and Ovid CAB Abstract databases were searched to identify English-language publications through 1 November 2019, including randomized trials, prospective cohort studies, and nested case-control (or case-cohort) studies with data on tea consumption and risk of incident cardiovascular events (cardiac or peripheral vascular events), stroke events (including mortality), CVD-specific mortality, or all-cause mortality. Data from 39 prospective cohort publications were synthesized. Linear meta-regression showed that each cup (236.6 mL)  increase in daily tea consumption (estimated 280 mg  and 338 mg  total flavonoids/d for black and green tea, respectively) was associated with an average 4% lower risk of CVD mortality, a 2% lower risk of CVD events, a 4% lower risk of stroke, and a 1.5% lower risk of all-cause mortality. Subgroup meta-analysis results showed that the magnitude of association was larger in elderly individuals for both CVD mortality (n = 4; pooled adjusted RR: 0.89; 95% CI: 0.83, 0.96; P = 0.001), with large heterogeneity (I2 = 72.4%), and all-cause mortality (n = 3; pooled adjusted RR: 0.92; 95% CI: 0.90, 0.94; P < 0.0001; I2 = 0.3%). Generally, studies with higher risk of bias appeared to show larger magnitudes of associations than studies with lower risk of bias. Strength of evidence was rated as low and moderate (depending on study population age group) for CVD-specific mortality outcome and was rated as low for CVD events, stroke, and all-cause mortality outcomes. Daily tea intake as part of a healthy habitual dietary pattern may be associated with lower risks of CVD and all-cause mortality among adults.

Coffee Consumption and Cardiovascular Disease: A Condensed Review of Epidemiological Evidence and Mechanisms

Coffee is one of the most widely consumed beverages, and some studies have suggested it may be related to cardiovascular disease (CVD), the leading cause of poor health in the world. This review evaluates the evidence on the effect of habitual coffee consumption on CVD incidence and mortality. The review is based mostly on observational studies and meta-analyses of the literature. In healthy people, in comparison to not consuming coffee, habitual consumption of 3-5 cups of coffee per day is associated with a 15% reduction in the risk of CVD, and higher consumption has not been linked to elevated CVD risk. Moreover, in comparison to no coffee intake, usual consumption of 1-5 cups/day is associated with a lower risk of death. In people who have already suffered a CVD event, habitual consumption does not increase the risk of a recurrent CVD or death. However, hypertensive patients with uncontrolled blood pressure should avoid consuming large doses of caffeine. In persons with well-controlled blood pressure, coffee consumption is probably safe, but this hypothesis should be confirmed by further investigations.

Higher Lipophilic Index Indicates Higher Risk of Coronary Heart Disease in Postmenopausal Women

Fatty acids (FAs) are essential components of cell membranes and play an integral role in membrane fluidity. The lipophilic index [LI, defined as the sum of the products between FA levels and melting points (°C), divided by the total amount of FA: [Formula: see text]] is thought to reflect membrane and lipoprotein fluidity and may be associated with the risk of coronary heart disease (CHD). Therefore, we examined the associations of dietary and plasma phospholipid (PL) LI with CHD risk among postmenopausal women. We determined dietary LI for the cohort with completed baseline food frequency questionnaires and free of prevalent cardiovascular diseases in the Women's Health Initiative (WHI) observational study (N = 85,563). We additionally determined plasma PL LI in a matched case-control study (N = 2428) nested within the WHI observational cohort study. Cox proportional hazard regression and multivariable conditional logistic regression were used to calculate HRs/ORs for CHD risk between quartiles of LI after adjusting for potential sources of confounding and selection bias. Higher dietary LI in the cohort study and plasma PL LI in the case-control study were significantly associated with increased risk of CHD: HR = 1.18 (95% CI 1.07-1.31, P for trend <0.01) and OR = 1.76 (95% CI 1.33-2.33, P for trend <0.01) comparing extreme quartiles and adjusting for potential confounders. These associations still persisted after adjusting for the polyunsaturated to saturated fat ratio. Our study indicated that higher LI based on either dietary or plasma measurements, representing higher FA lipophilicity, was associated with elevated risk of CHD among postmenopausal women.

Theoretical Effects of Substituting Butter with Margarine on Risk of Cardiovascular Disease

BACKGROUND

Several recent articles have called into question the deleterious effects of high animal fat diets due to mixed results from epidemiologic studies and the lack of clinical trial evidence in meta-analyses of dietary intervention trials. We were interested in examining the theoretical effects of substituting plant-based fats from different types of margarine for animal-based fat from butter on the risk of atherosclerosis-related cardiovascular disease (CVD).

METHODS

We prospectively studied 71,410 women, aged 50-79 years, and evaluated their risk for clinical myocardial infarction (MI), total coronary heart disease (CHD), ischemic stroke, and atherosclerosis-related CVD with an average of 13.2 years of follow-up. Butter and margarine intakes were obtained at baseline and year 3 by means of a validated food frequency questionnaire. Cox proportional hazards regression using a cumulative average diet method was used to estimate the theoretical effect of substituting 1 teaspoon/day of three types of margarine for the same amount of butter.

RESULTS

Substituting butter or stick margarine with tub margarine was associated with lower risk of MI (HRs = 0.95 and 0.91). Subgroup analyses, which evaluated these substitutions among participants with a single source of spreadable fat, showed stronger associations for MI (HRs = 0.92 and 0.87). Outcomes of total CHD, ischemic stroke, and atherosclerosis-related CVD showed wide confidence intervals but the same trends as the MI results.

CONCLUSIONS

This theoretical dietary substitution analysis suggests that substituting butter and stick margarine with tub margarine when spreadable fats are eaten may be associated with reduced risk of myocardial infarction.

Alcohol Consumption Levels and All-Cause Mortality Among Women Veterans and Non-Veterans Enrolled in the Women's Health Initiative

PURPOSE

To address research gaps regarding women Veterans' alcohol consumption and mortality risk as compared to non-Veterans, the current study evaluated whether alcohol consumption amounts differed between women Veterans and non-Veterans, whether Veterans and non-Veterans within alcohol consumption groups differed on all-cause mortality, and whether Veteran status modified the association between alcohol consumption and all-cause mortality.

DESIGN AND METHODS

Six alcohol consumption groups were created using baseline data from the Women's Health Initiative Program (N = 145,521): lifelong abstainers, former drinkers, less than 1 drink/week (infrequent drinkers), 1-7 drinks/week (moderate drinkers), 8-14 drinks/week (moderately heavy drinkers), and 15 or more drinks/week (heavy drinkers). The proportions of Veteran and non-Veteran women within each alcohol consumption category were compared. Mortality rates within each alcohol consumption category were compared by Veteran status. Cox proportional hazard models, including a multiplicative interaction term for Veteran status, were fit to estimate adjusted mortality hazard (rate) ratios for each alcohol consumption category relative to a reference group of either lifelong abstainers or moderate drinkers.

RESULTS

Women Veterans were less likely to be lifelong abstainers than non-Veterans. Women Veterans who were former or moderate drinkers had higher age-adjusted mortality rates than did non-Veterans within these alcohol consumption categories. In the fully adjusted multivariate models, Veteran status did not modify the association between alcohol consumption category and mortality with either lifelong abstainers or moderate drinkers as referents.

IMPLICATIONS

The results suggest that healthcare providers may counsel Veteran and non-Veteran women in similar ways regarding safe and less safe levels of alcohol consumption.

Rethinking cumulative exposure in epidemiology, again

The use of cumulative exposure, the product of intensity and duration, has enjoyed great popularity in epidemiology of chronic diseases despite numerous known caveats in its interpretation. We briefly review the history of use of cumulative exposure in epidemiology and propose an alternative method for relating time-integrated exposures to health risks. We argue, as others before us have, that cumulative exposure metrics obscures the interplay of exposure intensity and duration. We propose to use a computationally simple alternative in which duration and intensity of exposure are modelled as a main effect and their interaction, cumulative exposure, only be added if there is evidence of deviation from this additive model. We also consider the Lubin-Caporaso model of interplay of exposure intensity and duration. The impact of measurement error in intensity on model selection was also examined. The value of this conceptualization is demonstrated using a simulation study and further illustrated in the context of respiratory health and occupational exposure to latex dust. We demonstrate why cumulative exposure has been so popular because the cumulative exposure metric per se gives a robust answer to the existence of an association, regardless of the underlying true mechanism of disease. Treating cumulative exposure as the interaction of main effects of exposure duration and intensity enables epidemiologists to derive more information about mechanism of disease then fitting cumulative exposure metric by itself, and without the need to collect additional data. We propose that the practice of fitting duration, intensity and cumulative exposure separately to epidemiologic data should lead to conceptualization of cumulative exposure as interaction of main effects of duration and intensity of exposure.

The spectrum of epidemiology underlying sudden cardiac death

Sudden cardiac death (SCD) from cardiac arrest is a major international public health problem accounting for an estimated 15%-20% of all deaths. Although resuscitation rates are generally improving throughout the world, the majority of individuals who experience a sudden cardiac arrest will not survive. SCD most often develops in older adults with acquired structural heart disease, but it also rarely occurs in the young, where it is more commonly because of inherited disorders. Coronary heart disease is known to be the most common pathology underlying SCD, followed by cardiomyopathies, inherited arrhythmia syndromes, and valvular heart disease. During the past 3 decades, declines in SCD rates have not been as steep as for other causes of coronary heart disease deaths, and there is a growing fraction of SCDs not due to coronary heart disease and ventricular arrhythmias, particularly among certain subsets of the population. The growing heterogeneity of the pathologies and mechanisms underlying SCD present major challenges for SCD prevention, which are magnified further by a frequent lack of recognition of the underlying cardiac condition before death. Multifaceted preventative approaches, which address risk factors in seemingly low-risk and known high-risk populations, will be required to decrease the burden of SCD. In this Compendium, we review the wide-ranging spectrum of epidemiology underlying SCD within both the general population and in high-risk subsets with established cardiac disease placing an emphasis on recent global trends, remaining uncertainties, and potential targeted preventive strategies.

Mediterranean-style diet is associated with reduced blood pressure variability and subsequent stroke risk in patients with coronary artery disease

BACKGROUND AND PURPOSE

The Mediterranean-style diet is widely advocated for the prevention of cardiovascular diseases (CVD). Meanwhile, blood pressure variability (BPV) is a novel risk factor for CVD. It is unknown whether dietary pattern plays a role in modulating BPV.

METHODS

We prospectively followed-up 274 consecutive patients with stable coronary artery disease (CAD). The Mediterranean diet score (MDS) was derived for all individuals upon recruitment, blood pressure (BP) was measured during each subsequent clinic visit and the visit-to-visit BPV was calculated. The occurrence of major adverse cardiovascular events (MACEs) and all-cause mortality was monitored.

RESULTS

After a mean follow-up of 77±12 months, 16.1% of the study population developed MACEs. About 11.3% died from all causes. Patients who developed MACEs or all-cause mortality had a greater systolic BPV compared to those who did not develop an adverse event. Patients who developed a MACE had a lower MDS and further analysis revealed those who developed a stroke had a lower MDS compared with those who did not develop a stroke, but there were no significant differences in MDS between CAD patients with or without subsequent acute coronary syndrome, cardiovascular, or all-cause mortality. After adjusting for confounding variables, a high MDS was an independent predictor for low systolic BPV (B -0.74, 95% confidence interval -1.27 to -0.21, P < 0.01) and was noted to be protective against subsequent development of stroke (hazards ratio 0.48, 95% confidence interval 0.24 to 0.94, P = 0.03).

CONCLUSIONS

Among patients with CAD, a higher MDS is associated with a lower visit-to-visit BPV and with lower stroke risk.

Heart Rate Variability Differs between Right- and Left-Handed Individuals

Previous studies reported reduced longevity in left-handers with the suggestion that it may be associated with different heart diseases. Therefore, differences in heart rate variability (HRV), an index of autonomic cardiac activity, were examined for right- and left-handed individuals. 120 healthy young university students (75 women, 45 men; M age = 20.4 yr., SD = 1.5) volunteered. Handedness was assessed with the Edinburgh Handedness Inventory and HRV was measured via electrocardiography. The results suggest that the left-handers' HRV was significantly different from that of right-handers on several parameters. The atypical cerebral organization of left-handers may be related to an imbalanced autonomic system that results in higher frequencies of heart irregularities.