Effect of Varied Doses of Coffee-Caffeine on Resting Cardiovascular system of Healthy Black African Adults (original) (raw)
Cardiovascular effects of coffee and caffeine
The American Journal of Cardiology
This study evaluated the cardiovascular effects and elimination kinetics of coffee and caffeine in 54 volunteers selected according to 3 gradations of daily caffeine consumption, cigarette smoking status and the presence of caffeine intolerance. After 24 hours of caffeine abstinence, subjects received coffee and 2.2 mg/kg of caffeine (equivalent to 2 cups of coffee). Blood pressure, heart rate, systolic time intervals and plasma concentrations of caffeine were measured before and at timed intervals after coffee and caffeine. There were no differences in response to coffee and caffeine. The average systolic/diastolic blood pressure increased 9110 mm Hg. The maximal decrease in heart rate averaged 10 beats/min, and there were small increases in the systolic time intervals. There were no cardiovascular differences among the various groups. Caffeine in the smokers and heavy caffeiire users had a shorter half-life (3.2 and 4.1 hours) than that in nonsmokers and nonusers . in the caffeineintolerant group it had a longer half-life, while the cardiovascular effects were similar to those of the other groups. Thus, irrespective of the amount of daily caffeine consumption, smoking status or caffeine intolerance, the cardiovascular responses were similar and tolerance, if present, was gone by 24 hours.
Caffeine and cardiovascular health
This report evaluates the scientific literature on caffeine with respect to potential cardiovascular outcomes , specifically relative risks of total cardiovascular disease (CVD), coronary heart disease (CHD) and acute myocardial infarction (AMI), effects on arrhythmia, heart failure, sudden cardiac arrest, stroke, blood pressure, hypertension, and other biomarkers of effect, including heart rate, cerebral blood flow, cardiac output, plasma homocysteine levels, serum cholesterol levels, electrocardiogram (EKG) parameters , heart rate variability, endothelial/platelet function and plasma/urine catecholamine levels. Caffeine intake has been associated with a range of reversible and transient physiological effects broadly and cardiovascular effects specifically. This report attempts to understand where the de-lineations exist in caffeine intake and corresponding cardiovascular effects among various sub-populations. The available literature suggests that cardiovascular effects experienced by caffeine consumers at levels up to 600 mg/day are in most cases mild, transient, and reversible, with no lasting adverse effect. The point at which caffeine intake may cause harm to the cardiovascular system is not readily identifiable in part because data on the effects of daily intakes greater than 600 mg is limited. However, the evidence considered within this review suggests that typical moderate caffeine intake is not associated with increased risks of total cardiovascular disease; arrhythmia; heart failure; blood pressure changes among regular coffee drinkers; or hypertension in baseline populations.
Acute effects of coffee on QT interval in healthy subjects
Nutrition Journal, 2011
The coronary endothelial function is recognized to have an important role in the physiology of the diastolic ventricular relaxation, a phase of the heart cycle that influences the electrocardiographic QT interval. Endothelial function is investigated in vivo by flow mediated dilation (FMD) in the brachial artery and has proven to be a strong predictor of both coronary endothelial function and cardiovascular events. It has been reported that coffee acutely induces FMD changes. In particular, the brachial artery FMD seems to decrease after caffeinated coffee (CC) and to increase after decaffeinated coffee (DC) ingestion. Since the cardiovascular effects of coffee are still a debated matter, this study aimed at investigating with a randomized, double-blind crossover design, if the QT interval of adult healthy subjects (19 males and 21 females) changes in the hour following CC or DC ingestion. Both systolic and diastolic blood pressure were higher in the hour following the ingestion of CC; the heart rate significantly increased 30 minutes after CC ingestion. A significant increase of the QT duration was observed one hour after DC ingestion (398.9 ± 3.8 vs 405.3 ± 3.7 msec; P < 0.05), not after CC. The QT interval corrected for heart rate did not significantly change following CC or DC ingestion. In conclusion, despite CC and DC previously demonstrated to influence the FMD they do not seem to induce a significant unfavourable acute change of the left ventricular repolarization. Further investigations are required to elucidate the effects of coffee in subjects with cardiovascular diseases.
Effects of caffeine on vascular resistance, cardiac output and myocardial contractility in young men
American Journal of Cardiology, 1985
The mechanisms by which caffeine typically elevates blood pressure (BP) in humans have not been previously examined using a placebo-controlled design. Accordingly, oral caffeine (3.3 mg/kg body weight, equivalent to 2 to 3 cups of coffee) was given on 2 days and a placebo was given on 1 day to 15 healthy young men using a double-blind, crossover procedure. All 3 test sessions were held during a week of caffeine abstinence. Multiple measurements were made on subjects at rest (baseline values) and over a 45minute interval after ingestion of caffeine for BP, heart rate, systolic time intervals and thoracic impedance measures of ventricular function. Baseline measurements were highly reliable for each subject across all sessions and yielded means for placebo vs caffeine days that were not different. Caffeine increased systolic and diastolic BP (p <O.Ol) and decreased heart rate (p <0.05). The pressor effect was due to progressively increased systemic vascular resistance and resulted in greater stroke work (p <O-01). There was no indication that caffeine increased cardiac output or contractility. These actions of caffeine were replicable when each caffeine day was tested separately against the placebo day. These results suggest that caffeine use by persons with cardiovascular diseases should be examined to determine whether caffeine's enhancement of vascular resistance may contribute to systematic hypertension and/or create excessive demands for cardiac work.
Caffeine Consumption and Cardiovascular Risks: Little Cause for Concern
Journal of the American Heart Association, 2016
It is naturally found in coffee, tea, chocolate, and cola drinks. Furthermore, caffeine is often added to beverages, foods, pain relievers, and other products. In the United States, coffee accounts for 70% of the caffeine consumed. 1 A report in this issue of JAHA by Dixit and colleagues describes the relations between the reported intake of caffeinated products and the occurrence of arrhythmias assessed by 24-hour Holter monitoring in the Cardiovascular Health Study. The investigation included >1300 adults and all participants were >65 years of age at baseline. The authors report no association for atrial or ventricular arrhythmia prevalence and reported intake of caffeinated products. The Dixit article provides an opportunity to briefly review the pharmacology of caffeine related to the cardiovascular system and to share recent information and insights from clinical studies and population reports concerning caffeine intake and cardiovascular risk factors, cardiovascular disease (CVD) outcomes, and arrhythmias. In a mechanistic study published in the late 1970s, it was reported that 250 mg of caffeine, administered orally in a clinical research unit to adults not regularly ingesting caffeine products, raised plasma renin 57%, plasma norepinephrine 75%, plasma normetanephrine 207%, and blood pressure 14/ The opinions expressed in this article are not necessarily those of the editors or of the American Heart Association.
National Journal of Medical Research, 2013
Introduction: Coffee is one of the most widely consumed beverages in the world. It is the primary source of caffeine in many populations, but also contains several other biologically active components that may have either harmful or beneficial cardiovascular effects. Caffeine is widely consumed by people of all ages in India as well as many other countries. Methods: The study was conducted on 80 volunteers aged 21-40 years and with body mass index (BMI) between 17.3-28.0 kg /m2 .The subjects were divided into two groups: Control (n=40) (Age less than 25years )and Study group (n=40)(Age > 40 years). Results: Observation suggests that increment in systolic blood pressure (SBP) recorded in both the groups after coffee ingestion, but SBP increment was lesser in elderly person than that of control group. We also observe that there was decrease in heart rate in both study and control group, QTc was lower in control group. Conclusion: Coffee increases systolic and diastolic blood pressure but not the heart rate and the QTc interval. we also conclude that QTc interval is greater in elderly persons.
Cardiovascular effects of caffeine in men and women
The American Journal of Cardiology, 2004
Caffeine increases blood pressure (BP). In men, acute BP elevations after caffeine intake are due to an increase in vascular resistance, with no change in cardiac output. The hemodynamic effects of caffeine have not been studied in women. Accordingly, BP and hemodynamic responses to caffeine were measured in a double-blind trial comparing age-matched men and women at rest and during mental stress. Caffeine (3.3 mg/kg, equivalent to 2 to 3 cups of brewed coffee) or placebo was given to separate groups of women (n ؍ 21 and 21) and men (n ؍ 16 and 19) (mean ages 29 and 27 years, respectively). BP, cardiac output, and vascular resistance were observed at rest, during a stressful public-speaking simulation, reading aloud, and recovery. Caffeine caused nearly identical systolic and diastolic BP elevations in women (4.5 and 3.3 mm Hg, respectively) and men (4.1 and 3.8 mm Hg, respectively). Men given caffeine versus placebo showed the expected elevation in vascular resistance throughout the remainder of the protocol (p <0.001), with no difference in cardiac output. In contrast, women responded to caffeine with increases in stroke volume (p <0.001) and cardiac output (p <0.001), with no difference in vascular resistance from women taking placebo. Men and women have similar BP responses to caffeine, but the BP responses may arise from different hemodynamic mechanisms. Women who consume a dietary dose of caffeine showed an increase in cardiac output, whereas men showed increased vascular resistance. ᮊ2004 by Excerpta Medica, Inc.
Impact of coffee consumption on heart health: An Overview
International Journal of Cardiology Sciences, 2024
Communicating with evidence indicates that coffee consumption improves heart health, but a cautionary approach is recommended for individual differences. Bioactive compounds present in coffee such as polyphenols and diterpenes have antioxidant and anti-inflammatory properties that may positively affect vascular health. Nonetheless, there is a synthesis of epidemiological, clinical, and mechanistic studies undertaken on this subject. According to epidemiologic studies, moderate coffee consumption (3-5 cups) is inversely related to the risk of developing and dying from a number of cardiovascular conditions including coronary artery disease, stroke, and heart failure. However, it is important to note that too much of a good thing can have negative effects; those who are sensitive to caffeine or partake in excess consumption may experience arrhythmias, high blood pressure, or rapid heartbeats. It is also important to understand that the effects of coffee on heart health are influenced by lifestyle factors, genetic factors, and brewing techniques, and vice versa: coffee’s impact on heart health is a two-way street. Lastly, given the various benefits and risks that accompany coffee consumption, the review calls for tailored recommendations. To aid in gathering complete information and better serve the general public, further research must address the multifaceted relationships between coffee components, genetic predispositions, and cardiac events.
Coffee, caffeine and blood pressure: a critical review
European Journal of Clinical Nutrition, 1999
Objective: We review the published data relating to intake of coffee and caffeine on blood pressure in man. We also refer to studies on the possible mechanisms of actions of these effects of caffeine. Design: The MEDLINE and Current Contents databases were searched from 1966 to April 1999 using the text words`coffee or caffeine' and`blood pressure or hypertension'. Controlled clinical and epidemiologic studies on the blood pressure effects of coffee or caffeine are reviewed. We also refer to studies on the possible mechanisms of action of these effects of caffeine. Results: Acute intake of coffee and caffeine increases blood pressure. Caffeine is probably the main active component in coffee. The pressor response is strongest in hypertensive subjects. Some studies with repeated administration of caffeine showed a persistent pressor effect, whereas in others chronic caffeine ingestion did not increase blood pressure. Epidemiologic studies have produced contradictory ®ndings regarding the association between blood pressure and coffee consumption. During regular use tolerance to the cardiovascular responses develops in some people, and therefore no systematic elevation of blood pressure in long-term and in population studies can be shown. Conclusions: We conclude that regular coffee may be harmful to some hypertension-prone subjects. The hemodynamic effects of chronic coffee and caffeine consumption have not been suf®ciently studied. The possible mechanisms of the cardiovascular effects of caffeine include the blocking of adenosine receptors and the inhibition of phosphodiesterases.
Coffee Consumption and Cardiovascular Risk: An Updated Overview
Journal of Cardiology and Therapy, 2014
Coffee is one of the most widely consumed beverages worldwide. Since coffee contains caffeine, a stimulant, coffee drinking is not generally considered to be part of a healthy lifestyle. However, coffee is a rich source of antioxidants and other bioactive compounds, and many misconceptions persist regarding the health-related effects of coffee. Because of coffee is a complex beverage containing many bioactive compounds, its biological effects may be substantial and are not limited to the actions of caffeine; consequently, the health effects of chronic coffee intake are wide ranging. Coffee consumption may reduce the risk of type 2 diabetes mellitus, hypertension, obesity and depression, but it may adversely affect lipid profiles depending on how the beverage is prepared. A growing body of evidences suggests that habitual coffee consumption is neutral to beneficial regarding the risks of a variety of adverse cardiovascular outcomes including coronary heart disease, congestive heart failure, arrhythmias, and REVIEW
Journal of the American College of Cardiology, 2013
Coffee is the most widely consumed beverage in the United States (US) after water, and is the principal source of caffeine intake among adults. The biological effects of coffee may be substantial and are not limited to the actions of caffeine. Coffee is a complex beverage containing hundreds of biologically-active compounds, and the health effects of chronic coffee intake are wide ranging. From a cardiovascular (CV) standpoint, coffee consumption may reduce the risks of type 2 diabetes mellitus (T2DM) and hypertension (HTN), as well as other conditions associated with CV risk such as obesity and depression; but it may adversely affect lipid profiles depending on how the beverage is prepared. Regardless, a growing body of data suggests that habitual coffee consumption is neutral to beneficial regarding the risks for a variety of adverse CV outcomes including coronary heart disease (CHD), congestive heart failure (CHF), arrhythmias, and stroke. Moreover, large epidemiological studies suggest that regular coffee drinkers have reduced risks for mortality-both CV and all-cause. The potential benefits also include protection against neurodegenerative diseases, improved asthma control, and lower risk of select gastrointestinal diseases. A daily intake of about 2 to 3 cups of coffee appears to be safe and is associated with neutral to beneficial effects for most of the studied health outcomes. However, most of the data on coffee's health effects are based upon observational data, with very few randomized controlled studies, and association does not prove causation. Additionally, the possible advantages of regular coffee consumption have to be weighed against potential risks (which are mostly related to its high caffeine content) including anxiety, insomnia, tremulousness and palpitations, as well as bone loss and possibly increased risk of fractures.
The Effect of Caffeine on Heart Rate
The pace at which the heart beats is one of the best measures of the general health of a person. Many medical disorders can be identified from the patient's heart rate data in a clinical context (Shaffer & Ginsberg, 2017). Premiere Hospital of Newport Beach (PHNB) recognizes the significance of the heart rate in diagnosing and is interested in learning whether offering patients caffeinated coffee in the waiting area affects their heart rate. Researchers at PHNB investigated the effects of caffeine on the heart rate by conducting an investigation in which the heart rates of people waiting rooms were measured both before and after receiving a cup of coffee. Those in need of care at the institution made up the sample for this research. A random sample of 31 patients was selected from this group depending on how easily they could be reached. While this sampling strategy required little effort on the part of the researchers, it did introduce a restriction on the study's ability to generalize to the community at large. Yet, we were able to utilize the sample to delve further into the study's central mystery. Quantitative data were the focus of this investigation. Each patient's heart rate was monitored before and after they drank caffeinated coffee to see whether there were any noticeable changes. Interval (3rd level of assessment) was used since it revealed both the relative position of the variables and the gap among them. This research used blood caffeine levels as the independent variable. The number of times the heart beats in a minute served as the dependent variable in this study. The patients' underlying health conditions were an uncontrolled variable in the trial. The effects of caffeine on various medical disorders may vary.
Coffee and cardiovascular disease: In vitro, cellular, animal, and human studies
Pharmacological Research, 2007
Coffee is a commonly consumed beverage with potential health benefits. This review will focus on cardiovascular disease. There are three preparations of coffee that are commonly consumed and thus worthy of examination; boiled unfiltered coffee, filtered coffee, and decaffeinated coffee. Coffee has over a thousand chemicals, many formed during the roasting process. From a physiological point of view, the potential bioactives are caffeine, the diterpenes cafestol and kahweol found in the oil, and the polyphenols, most notably chlorogenic acid. We will examine coffee and its bioactives and their connection with and effect on the risk factors which are associated with heart disease such as lipids, blood pressure, inflammation, endothelial function, metabolic syndrome and potentially protective in vivo antioxidant activity. These will be critically examined by means of in vitro studies, cell experiments, animal supplementation, epidemiology, and the most definitive evidence, human trials.
American Journal of Clinical Nutrition, 2011
Background: The effect of coffee and caffeine on blood pressure (BP) and cardiovascular disease (CVD) in hypertensive persons is uncertain. Objective: The objective was to summarize the evidence on the acute and longer-term effects of caffeine and coffee intake on BP and on the association between habitual coffee consumption and risk of CVD in hypertensive individuals. Design: A systematic review and meta-analysis of publications identified in a PubMed and EMBASE search up to 30 April 2011 was undertaken. Data were extracted from controlled trials on the effect of caffeine or coffee intake on BP change and from cohort studies on the association between habitual coffee consumption and CVD. Results: In 5 trials, the administration of 200-300 mg caffeine produced a mean increase of 8.1 mm Hg (95% CI: 5.7, 10.6 mm Hg) in systolic BP and of 5.7 mm Hg (95% CI: 4.1, 7.4 mm Hg) in diastolic BP. The increase in BP was observed in the first hour after caffeine intake and lasted !3 h. In 3 studies of the longer-term effect (2 wk) of coffee, no increase in BP was observed after coffee was compared with a caffeine-free diet or was compared with decaffeinated coffee. Last, 7 cohort studies found no evidence of an association between habitual coffee consumption and a higher risk of CVD. Conclusions: In hypertensive individuals, caffeine intake produces an acute increase in BP for !3 h. However, current evidence does not support an association between longer-term coffee consumption and increased BP or between habitual coffee consumption and an increased risk of CVD in hypertensive subjects.
Coffee components and cardiovascular risk: beneficial and detrimental effects
2014
Coffee consists of several biological active compounds, such as caffeine, diterpenes, chlorogenic acids, and melanoidins, which may affect human health. The intake of each compound depends on the variety of coffee species, roasting degree, type of brewing method and serving size. The bioavailability and the distribution of each compound and its metabolites also contribute to coffee mechanisms of action. The health benefits of coffee consumption regarding cardiovascular system and metabolism mostly depend on its antioxidant compounds. In contrast, diterpenes and caffeine may produce harmful effects by raising lipid fraction and affecting endothelial function, respectively. Studying the mechanism of action of coffee components may help understanding weather coffee's impact on health is beneficial or hazardous. In this article, we reviewed the available information about coffee compounds and their mechanism of action. Furthermore, benefits and risks for cardiovascular system associated with coffee consumption will be discussed.
2019
Introduction: Coffee is one of the most consumed beverages worldwide and its effect on health has not been clearly established. There is a special controversy about its effects on the cardiovascular system. The objective of this work is to synthesize the evidence on the effects of habitual coffee consumption on cardiovascular health. Methods: Review of systematic reviews of the literature published in English, Spanish, French and Portuguese in biomedical databases (Medline, Embase, Cochrane, and Lilacs). The search will be supplemented with manual searching of references of the included reviews. The information will be selected and extracted separately by two researchers, and disagreements will be resolved by consensus. The included reviews will be grouped by year of publication, outcomes, design of original studies and quality. The study will apply the Assessing Methodological Quality for Systematic Reviews checklists to assess the methodological quality of the systematic reviews. ...
Caffeine effects on several indices of cardiovascular activity at rest and during stress
J Behav Med, 1988
The effects of caffeine on cardiovascular responses to a mental arithmetic task were assessed using a between-subjects, double-blind design. Thirty-six male undergraduates were randomly assigned to either a placebo group or a group which received 250mg of caffeine. Repeated measurements of systolic and diastolic blood pressure (SBP, DBP), heart rate (HR), digital blood volume pulse (DB VP), and finger pulse transit time (FPTT) were obtained during a predrug baseline, a postdrug resting period, and a mental arithmetic task. Significant Period O.e., stress) effects were observed on all measures, except DBVP which revealed a marginally significant Period effect. Significant main effects of Drug were observed on DBP and DB VP. There were no significant Drug x Period interactions. These results indicate that the increases in DBP and the decreases in DB VP produced by caffeine were additive with effects produced by stress.
Coffee for Cardioprotection and Longevity
Progress in cardiovascular diseases
Coffee, a complex brew containing hundreds of biologically active compounds, exerts potent effects on long-term human health. Recently, a plethora of studies have been published focusing on health outcomes associated with coffee intake. An inverse association between coffee consumption and all-cause mortality has been seen consistently in large prospective studies. Habitual coffee consumption is also associated with lower risks for cardiovascular (CV) death and a variety of adverse CV outcomes, including coronary heart disease (CHD), congestive heart failure (HF), and stroke; coffee's effects on arrhythmias and hypertension are neutral. Coffee consumption is associated with improvements in some CV risk factors, including type 2 diabetes (T2D), depression, and obesity. Chronic coffee consumption also appears to protect against some neurodegenerative diseases, and is associated with improved asthma control, and lower risks for liver disease and cancer. Habitual intake of 3 to 4 cu...
Effect of coffee on blood pressure and electrocardiographic changes in nicotine users
Asian Journal of Medical Sciences, 2014
Objectives: The objectives of this study were to see the effect of coffee on Heart rate Blood pressure and ECG changes in nicotine users.Methods: The study was conducted on 120 volunteers aged 21-40 years and with body mass index (BMI) between 17.3-28.0 kg /m2 .The subjects were divided into two groups: Control (n=40) and Study group (n=80).Results: Observation suggests that increment in blood pressure, recorded in study group after coffee ingestion, was lesser than that of control group. We also observed that there were no significant changes in diastolic blood pressure in any group while the mean arterial pressure was higher in both the groups following coffee ingestion.Conclusion: Coffee ingestion decreases the heart rate with no changes in QTc, hence we concluded that less amount of coffee ingestion may not be harmful.DOI: http://dx.doi.org/10.3126/ajms.v6i3.10090Asian Journal of Medical Sciences Vol.6(3) 2015 46-48