Cited by 135Cardiovascular Health and Disease PreventionCoffee research and impactsCardiovascular Function and Risk Factors

Smoking and caffeine have a synergistic detrimental effect on aortic stiffness and wave reflections

Open access
Vlachopoulos, Charalambos, Kosmopoulou, Foteini, Panagiotakos, Demosthenes, Ioakeimidis, Nikolaos, Alexopoulos, Nikolaos, Pitsavos, Christos, Stefanadis, Christodoulos·2004·Journal of the American College of Cardiology

Abstract

Objectives We investigated the acute and chronic combined effect of cigarette smoking and caffeine intake on aortic stiffness and wave reflections.Background We have shown that smoking and caffeine separately increase arterial stiffness. Aortic stiffness and wave reflections are important determinants of the efficient performance of the cardiovascular system and prognosticators of cardiovascular risk.Methods The acute effects of smoking (one cigarette), caffeine (200 mg, equivalent to 2 cups of coffee), and smoking plus caffeine were studied in 24 healthy subjects according to a randomized, placebo- and sham procedure-controlled crossover design. The chronic effect of smoking and caffeine was studied in a population study that enrolled 160 healthy subjects.Results Acute study: there was a significant interaction between caffeine and smoking with regard to pulse-wave velocity (p < 0.01) and augmentation index (p < 0.05). When smoking followed caffeine intake, pulse-wave velocity and augmentation index increased further by 0.52 m/s and 13.4%, respectively, reaching a total of 0.85 m/s and 17.4%, 0.17 m/s and 9.2% in excess of the mere sum of caffeine effect (0.33 m/s and 4%) alone and smoking effect alone (0.35 m/s and 4.2%). Population study: there was a significant interaction of chronic coffee consumption and smoking regarding pulse-wave velocity (p < 0.05) and augmentation index (p = 0.001).Conclusions The present study shows, for the first time, that when smoking and caffeine intake are combined, they interact and exert a synergistic, unfavorable effect on aortic stiffness and wave reflections on both an acute and chronic basis.

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Written from the paper’s full text.

TL;DR

In healthy adults, combined caffeine and smoking produced acute synergistic worsening of aortic stiffness and wave reflections beyond the sum of their individual effects. A chronic population study also found significant interactions between coffee drinking and smoking on pulse-wave velocity, augmentation index, augmented pressure, and subendocardial viability index.

Key findings

  • Acute study: significant caffeine–smoking interaction for pulse-wave velocity (p < 0.01) and heart-rate-corrected augmentation index (p < 0.05). When smoking followed caffeine, pulse-wave velocity increased further by 0.52 m/s to a total of 0.85 m/s, 0.17 m/s above the sum of caffeine alone (0.33 m/s) and smoking alone (0.35 m/s); augmentation index increased further by 13.4% to 17.4%, 9.2% above the sum of caffeine alone (4%) and smoking alone (4.2%).
  • Acute central pressures also showed significant interaction: smoking after caffeine increased central systolic, diastolic, and pulse pressures further by 7.5, 4.4, and 3.1 mm Hg, reaching peak increases of 16.4, 11.7, and 4.7 mm Hg, respectively. Ejection duration decreased further by 16.2 ms to −16.6 ms, 11.7 ms less than the sum of individual effects; subendocardial viability index interaction was p < 0.001.
  • Population study: among 160 subjects, chronic coffee consumption and smoking interacted significantly for pulse-wave velocity (p < 0.05), augmentation index (p = 0.001), augmented pressure (p < 0.005), and subendocardial viability index (p = 0.001). Table values showed pulse-wave velocity 6.36 m/s in coffee drinkers/smokers, 6.31 m/s in coffee drinkers/nonsmokers, and 5.80 m/s in neither (p = 0.05); augmentation index 22.7%, 21.7%, and 11.0% (p = 0.001); subendocardial viability index 145.0%, 140.8%, and 156.1% (p = 0.005).
  • No effect of gender was found on any of the significant interactions.

Methods

  • Acute study: randomized, placebo- and sham procedure-controlled crossover design in 24 healthy current smokers and regular caffeine consumers (>100 mg/day). Four sessions were smoking one standard cigarette (1.1 mg nicotine) over 5 min, sham smoking, caffeine 200 mg plus smoking 60 min later, and placebo plus sham smoking. Aortic stiffness was studied in 14 subjects (7 women, 7 men; age 30 ± 2 years) and wave reflections in 10 subjects (5 women, 5 men; age 33 ± 3 years).
  • Population study: 160 clinically healthy employees (79% participation rate) were grouped as 97 chronic smokers and coffee drinkers, 41 chronic coffee drinkers and nonsmokers, 2 chronic smokers but not coffee drinkers (data not shown), and 20 neither coffee consumers nor smokers. Measurements were taken in the morning after an overnight fast.
  • Main measures/analysis: carotid–femoral pulse-wave velocity (Complior) and augmentation index, augmented pressure, and subendocardial viability index (SphygmoCor). Multi-way analysis of covariance for repeated measurements was used, with adjustments for mean pressure, heart rate, age, and gender; Bonferroni correction was applied. Power calculation indicated 160 participants provided >0.80 power at p < 0.05.

Limitations

  • Stated: the study refers to young, apparently healthy adults, and results might not be directly extendable to other population groups. The basic mechanism responsible for the interactive effect is unclear.
  • Stated/evident: the population groups differed significantly in age (p = 0.001), although analyses were age-adjusted; the chronic population study is cross-sectional and cannot establish causality.
  • Evident: the acute study sample was small (24 total; 14 and 10 in the two measurement groups), and all acute participants were current smokers and regular caffeine consumers, limiting generalizability.

Model-written summary. Check it against the paper before relying on it.

Integrity signals

Registry

Crossref · 10.1016/j.jacc.2004.07.049

Cites

40 of 40 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Claims the paper makes

0 of 39 cited sources checked · 0 supported · 0 flagged

  • Findingown data

    In the population study, there was a significant interaction of chronic coffee consumption and smoking regarding pulse-wave velocity (p < 0.05).

    “Population study: there was a significant interaction of chronic coffee consumption and smoking regarding pulse-wave velocity (p Ͻ 0.05)”
    • Also stated in: § Population study. · hedged
      “Furthermore, a significant interaction was observed between chronic smoking and coffee consumption on pulse-wave velocity (p Ͻ 0.05), indicating a synergistic effect of the two habits.”
    Quote in the paperSubstantial claim
    • Rests on an assumption: The observed associations between chronic smoking/coffee consumption and arterial stiffness are not due to unmeasured confounding.
  • Findingown data

    In the population study, there was a significant interaction of chronic coffee consumption and smoking regarding augmentation index (p = 0.001).

    “and augmentation index (p ϭ 0.001)”
    • Also stated in: § Population study. · plain
      “In addition, a significant interaction was observed between chronic smoking and coffee consumption on the augmentation index and augmented pressure (p ϭ 0.001 and p Ͻ 0.005, respectively) after correction for height and HR.”
    Quote in the paperSubstantial claim
    • Rests on an assumption: The observed associations between chronic smoking/coffee consumption and arterial stiffness are not due to unmeasured confounding.
  • Findingown data

    In the acute study, there was a significant interaction between caffeine and smoking with regard to pulse-wave velocity (p < 0.01).

    “there was a significant interaction between caffeine and smoking with regard to pulse-wave velocity (p Ͻ 0.01)”
    • Also stated in: § Acute study. · plain
      “There was a significant interaction (p Ͻ 0.01) between caffeine and smoking regarding pulse-wave velocity, indicating a synergistic effect of the two interventions leading to a significant deterioration in aortic stiffness.”
    Quote in the paperSubstantial claim
    • Rests on an assumption: The acute effects of smoking and caffeine on arterial stiffness are not affected by carryover effects between the four study sessions.
  • Findingown data

    In the acute study, there was a significant interaction between caffeine and smoking with regard to augmentation index (p < 0.05).

    “and augmentation index (p Ͻ 0.05)”
    • Also stated in: § 2, diamonds). · plain
      “There was a significant interaction (p Ͻ 0.05) between caffeine and smoking with regard to augmentation index corrected for changes in HR, indicating a synergistic effect of the two interventions leading to a significant increase in wave reflections.”
    Quote in the paperSubstantial claim
    • Rests on an assumption: The acute effects of smoking and caffeine on arterial stiffness are not affected by carryover effects between the four study sessions.
  • Findingreasoning

    The increase in aortic stiffness when smoking was added to caffeine was proportionally larger than the respective increase in blood pressure.

    “This is also corroborated by the fact that the increase in the aortic stiffness when smoking was added to caffeine was proportionally larger than the respective increase in blood pressure.”
    Quote in the paperSubstantial claim
  • May combine two claims. 9
  • Classified as probably not a substantial claim. 11
  • May combine two claims.

    Findingown data

    When smoking followed caffeine intake, augmentation index increased further by 13.4%, reaching a total increase of 17.4%, which is 9.2% in excess of the sum of the caffeine effect alone (4%) and the smoking effect alone (4.2%).

    “When smoking followed caffeine intake, pulse-wave velocity and augmentation index increased further by 0.52 m/s and 13.4%, respectively, reaching a total of 0.85 m/s and 17.4%, 0.17 m/s and 9.2% in excess of the mere sum of caffeine effect (0.33 m/s and 4%) alone and smoking effect alone (0.35 m/s and 4.2%).”
    • Also stated in: § 2, diamonds). · plain
      “When smoking followed caffeine intake, the augmentation index increased to 17.4%, 9.2% in excess of the mere sum of caffeine effect (4%) alone and smoking effect alone (4.2%) (Fig. 3, diamonds).”
    Quote in the paperSubstantial claim
    • Rests on an assumption: The acute effects of smoking and caffeine on arterial stiffness are not affected by carryover effects between the four study sessions.
  • May combine two claims.

    Findingown data

    When smoking followed caffeine intake, pulse-wave velocity increased further by 0.52 m/s, reaching a total increase of 0.85 m/s, which is 0.17 m/s in excess of the sum of the caffeine effect alone (0.33 m/s) and the smoking effect alone (0.35 m/s).

    “When smoking followed caffeine intake, pulse-wave velocity and augmentation index increased further by 0.52 m/s and 13.4%, respectively, reaching a total of 0.85 m/s and 17.4%, 0.17 m/s and 9.2% in excess of the mere sum of caffeine effect (0.33 m/s and 4%) alone and smoking effect alone (0.35 m/s and 4.2%).”
    • Also stated in: § DISCUSSION · plain
      “When smoking followed caffeine intake, pulse wave velocity reached a total increase of 0.85 m/s, 0.17 m/s in excess of the mere sum of caffeine effect (0.33 m/s) alone and smoking effect alone (0.35 m/s) (Fig.”
    Quote in the paperSubstantial claim
    • Rests on an assumption: The acute effects of smoking and caffeine on arterial stiffness are not affected by carryover effects between the four study sessions.
  • May combine two claims.

    Findingown data

    In the population study, coffee consumers/nonsmokers and coffee consumers/smokers had lower subendocardial viability index levels compared with non-coffee consumers/nonsmokers (p < 0.005 and p < 0.05, respectively) after correction for heart rate.

    “Coffee consumers/nonsmokers, as well as coffee consumers/smokers, had lower subendocardial viability index levels compared with non-coffee consumers/nonsmokers (p Ͻ 0.005 and p Ͻ 0.05, respectively) after correction for HR.”
    Quote in the paperSubstantial claim
    • Rests on an assumption: The observed associations between chronic smoking/coffee consumption and arterial stiffness are not due to unmeasured confounding.
  • May combine two claims.

    Findingown data

    In the population study, there were significant interactions between chronic smoking and coffee consumption regarding peripheral diastolic pressure, peripheral and central mean pressure, central systolic pressure, and central diastolic pressure (p < 0.05), whereas central pulse pressure showed a marginal trend (p = 0.07).

    “Significant interactions between chronic smoking and coffee consumption were also observed regarding peripheral diastolic pressure (p Ͻ 0.05), peripheral and central mean pressure (p Ͻ 0.05), central systolic pressure (p Ͻ 0.05), and central diastolic pressure (p Ͻ 0.05), whereas central pulse pressure showed a marginal trend (p ϭ 0.07).”
    Quote in the paperSubstantial claim
    • Rests on an assumption: The observed associations between chronic smoking/coffee consumption and arterial stiffness are not due to unmeasured confounding.
  • Classified as probably not a substantial claim. May combine two claims.

    Premisecitation

    Large-artery stiffness and wave reflections have been identified as markers of cardiovascular disease and independent prognosticators of cardiovascular risk.

    “Large-artery stiffness and wave reflections are important determinants of left ventricular (LV) function, coronary blood flow, and mechanical integrity of arteries and have been identified as markers of cardiovascular disease and independent prognosticators of cardiovascular risk (4 -12).”
    Quote in the paperSubstantial claim0 of 9 sources checked
    • cites [4] Nichols, 1998

      Not checked in the free run.

    • cites [5] Vlachopoulos, 2000, Genesis of the normal and abnormal arterial pulse, Curr Probl Cardiol source

      Not checked in the free run.

    • cites [6] Kelly, 1992, Effect of reduced aortic compliance in cardiac efficiency and contractile function of in situ canine left ventricle, Circ Res source

      Not checked in the free run.

    • cites [7] Watanabe, 1993, Coronary circulation in dogs with an experimental decrease in aortic compliance, J Am Coll Cardiol source

      Not checked in the free run.

    • cites [8] Blacher, 1999, Aortic pulse wave velocity as a marker of cardiovascular risk in hypertensive patients, Hypertension source

      Not checked in the free run.

    • cites [9] Stefanadis, 2000, Aortic stiffness as a risk factor for recurrent acute coronary events in patients with ischaemic heart disease, Eur Heart J source

      Not checked in the free run.

    • cites [10] Laurent, 2001, Aortic stiffness is an independent predictor of all-cause and cardiovascular mortality in hypertensive patients, Hypertension source

      Not checked in the free run.

    • cites [11] London, 2001, Arterial wave reflections and survival in end-stage renal failure, Hypertension source

      Not checked in the free run.

    • cites [12] Weber, 2004, Arterial stiffness, wave reflections, and the risk of coronary artery disease, Circulation source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    Active and passive smoking and caffeine separately increase arterial stiffness and wave reflections.

    “We and others have previously shown that active and passive smoking (13)(14)(15) and caffeine (16 -19) increase arterial stiffness and wave reflections.”
    Quote in the paperSubstantial claim0 of 5 sources checked
    • cites (13)(14)(15)

      Not checked in the free run.

    • cites [16] Vlachopoulos, 2001, Pressure-altering agents affect central aortic pressures more than is apparent from upper limb measurements in hypertensive patients: the role of arterial wave reflections, Hypertension source

      Not checked in the free run.

    • cites [17] Vlachopoulos, 2003, Caffeine increases aortic stiffness in hypertensive patients, Am J Hypertens source

      Not checked in the free run.

    • cites [18] Vlachopoulos, 2003, Effect of caffeine on aortic elastic properties and wave reflection, J Hypertens source

      Not checked in the free run.

    • cites [19] Mahmud, 2001, Acute effect of caffeine on arterial stiffness and aortic pressure waveform, Hypertension source

      Not checked in the free run.

  • Classified as probably not a substantial claim.

    Premisecitation

    Large-artery stiffness and wave reflections are important determinants of left ventricular function, coronary blood flow, and mechanical integrity of arteries.

    “Large-artery stiffness and wave reflections are important determinants of left ventricular (LV) function, coronary blood flow, and mechanical integrity of arteries and have been identified as markers of cardiovascular disease and independent prognosticators of cardiovascular risk (4 -12).”
    Quote in the paperSubstantial claim0 of 9 sources checked
    • cites [4] Nichols, 1998

      Not checked in the free run.

    • cites [5] Vlachopoulos, 2000, Genesis of the normal and abnormal arterial pulse, Curr Probl Cardiol source

      Not checked in the free run.

    • cites [6] Kelly, 1992, Effect of reduced aortic compliance in cardiac efficiency and contractile function of in situ canine left ventricle, Circ Res source

      Not checked in the free run.

    • cites [7] Watanabe, 1993, Coronary circulation in dogs with an experimental decrease in aortic compliance, J Am Coll Cardiol source

      Not checked in the free run.

    • cites [8] Blacher, 1999, Aortic pulse wave velocity as a marker of cardiovascular risk in hypertensive patients, Hypertension source

      Not checked in the free run.

    • cites [9] Stefanadis, 2000, Aortic stiffness as a risk factor for recurrent acute coronary events in patients with ischaemic heart disease, Eur Heart J source

      Not checked in the free run.

    • cites [10] Laurent, 2001, Aortic stiffness is an independent predictor of all-cause and cardiovascular mortality in hypertensive patients, Hypertension source

      Not checked in the free run.

    • cites [11] London, 2001, Arterial wave reflections and survival in end-stage renal failure, Hypertension source

      Not checked in the free run.

    • cites [12] Weber, 2004, Arterial stiffness, wave reflections, and the risk of coronary artery disease, Circulation source

      Not checked in the free run.

  • Classified as probably not a substantial claim.

    Study design and conductcitation

    Augmentation index was measured using a validated, commercially available system (SphygmoCor).

    “The augmentation index was measured by using a validated, commercially available system (SphygmoCor; AtCor Medical, Sydney, Australia) that employs the principle of applanation tonometry and appropriate acquisition and analysis software for noninvasive recording and analysis of the arterial pulse.”
    Quote in the paperSubstantial claim0 of 3 sources checked
    • cites [4] Nichols, 1998

      Not checked in the free run.

    • cites [27] Karamanoglu, 1993, An analysis of the relationship between central aortic and peripheral upper limb pressure waves in man, Eur Heart J source

      Not checked in the free run.

    • cites [28] Chen, 1997, Estimation of central aortic pressure waveform by mathematical transformation of radial tonometry pressure, Circulation source

      Not checked in the free run.

  • Classified as probably not a substantial claim.

    Study design and conductcitation

    Augmentation index was corrected for changes in heart rate.

    “Because the augmentation index is influenced by changes in heart rate (HR), it was also accordingly corrected (26).”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [26] Cameron, 1998, Use of radial artery applanation tonometry and a generalized transfer function to determine aortic pressure augmentation in subjects with treated hypertension, J Am Coll Cardiol source

      Not checked in the free run.

  • May combine two claims.

    Interpretationown data

    Neither smoking nor caffeine exhausts the capacity of the vessel's elastic properties to deteriorate; there is room for further deterioration when a harmful intervention is added.

    “Another interesting interpretation of the results of our study is that neither stimulus”
    Quote in the paperSubstantial claim
  • Probably not a substantial claim: may not pass S2 (checkable).

    Interpretationreasoning

    Given the frequent combination of smoking and caffeine intake, the effects on arterial function may have important implications for human health.

    “Consequently, given the frequent combination of smoking and caffeine intake, these effects on arterial function may have important implications for human health.”
    Quote in the paperNot a substantial claim
  • Classified as probably not a substantial claim.

    Study design and conductcitation

    Pulse-wave velocity was measured using a validated noninvasive device (Complior).

    “using a validated noninvasive device (Complior; Artech Medical, Pantin, France) that allows online pulse-wave recording and automatic calculation of pulse-wave velocity (25).”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [25] Asmar, 1995, Assessment of arterial distensibility by automatic pulse wave velocity measurement: validation and clinical application studies, Hypertension source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductreasoning

    Bonferroni correction was used to account for multiple comparisons.

    “However, because of multiple comparisons, we used the Bonferroni correction in order to account for the increase in type I error.”
    Quote in the paperNot a substantial claim
  • Classified as probably not a substantial claim.

    Study design and conductown data

    Statistical analysis adjusted for mean pressure and heart rate in multivariate regression models.

    “To take into account the potential effect of pressure changes on pulse-wave velocity and of HR changes on subendocardial viability index, we adjusted in multivariate regression models for mean pressure and HR, respectively.”
    Quote in the paperSubstantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Interpretationnone given

    The study's results refer to young, apparently healthy adults and might not be directly extendable to other population groups.

    “Our study refers to young, apparently healthy adults, and results might not be directly extendable to other population groups.”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Premisecitation

    Wave reflection indices may be influenced by changes in heart rate and by height, and subendocardial viability index by changes in heart rate.

    “Wave reflection indices may be influenced by changes in HR and by height and subendocardial viability index by changes in HR.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [26] Cameron, 1998, Use of radial artery applanation tonometry and a generalized transfer function to determine aortic pressure augmentation in subjects with treated hypertension, J Am Coll Cardiol source

      Not checked in the free run.

  • Classified as probably not a substantial claim.

    Study design and conductown data

    The acute study used a randomized, placebo-and sham procedure-controlled crossover design.

    “The study was carried out using a randomized placebo-and sham procedurecontrolled crossover design.”
    Quote in the paperSubstantial claim
  • Classified as probably not a substantial claim.

    Study design and conductown data

    The population study analyses were adjusted for age and gender.

    “The involvement of the interaction between chronic coffee intake and smoking on the investigated parameters was evaluated using multi-way analysis of covariance after adjusting for age and gender.”
    • Also stated in: § Population study. · plain
      “Because the age of the participants differed significantly in the groups of the study, all the analyses carried out were age-adjusted.”
    Quote in the paperSubstantial claim
18 of 18
  • The paper relies on this without support.

    The observed associations between chronic smoking/coffee consumption and arterial stiffness are not due to unmeasured confounding.

    “The involvement of the interaction between chronic coffee intake and smoking on the investigated parameters was evaluated using multi-way analysis of covariance after adjusting for age and gender.”
  • The paper relies on this without support.

    The acute effects of smoking and caffeine on arterial stiffness are not affected by carryover effects between the four study sessions.

    “Each subject was studied fasting on four separate days before and after 1) smoking one standard cigarette (1.1 mg nicotine) over 5 min, 2) sham smoking, 3) caffeine intake (200 mg, a dose equivalent to 2 cups of coffee) plus smoking one standard cigarette (1.1 mg nicotine) 60 min after caffeine intake, and 4) placebo (to caffeine) and sham smoking 60 min after placebo intake.”
2 of 2

Claims other papers make about this one

Each is checked against this paper’s own text: does it say what the citing paper says it does?

  • Evidence from experimental studies indicates that coffee acutely increases circulating concentrations of (nor)epinephrine, raises systolic and diastolic blood pressure, increases arterial stiffness, and impairs endothelium-dependent vasodilation.

    “Evidence from experimental studies indicates that coffee acutely increases circulating concentrations of (nor)epinephrine, 2 raises systolic and diastolic blood pressure, 3 increases arterial stiffness, 5,6 and impairs endothelium-dependent vasodilation.7”

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

  • Pulse pressure does not match systolic minus diastolic pressure in the smoking session

    Minor

    In Table 2's smoking session, peripheral systolic pressure minus diastolic pressure is 50.4 mm Hg, not the reported pulse pressure of 51.2 mm Hg.

    Reported 51.2 · recomputed 50.4

1 of 1

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Authors
Vlachopoulos, C., Kosmopoulou, F., Panagiotakos, D., Ioakeimidis, N., Alexopoulos, N., Pitsavos, C., & Stefanadis, C.
Affiliations
Hippocration General Hospital (GR)
Corresponding author
Vlachopoulos, Charalambos
Venue
Journal of the American College of Cardiology
Publisher
Elsevier BV
Published
2004-11
Volume
44
Issue
9
Pages
1911-1917
ISSN
0735-1097 (ISSN-L)
OpenAlex
W2071910605
Cited by
135
References
41
Citations by year
2026: 3 · 2025: 1 · 2024: 6 · 2023: 2 · 2022: 6 · 2021: 4 · 2020: 4 · 2019: 6 · 2018: 5 · 2017: 4 · 2016: 6 · 2015: 9 · 2014: 7 · 2013: 6 · 2012: 3
FWCI
7.19
Type
journal article
Language
en
Open access
Locations
  • Journal of the American College of Cardiology (publishedVersion)
  • PubMed (publishedVersion)
Topics
  • Health Sciences › Medicine › Cardiology and Cardiovascular Medicine › Cardiovascular Health and Disease Prevention
  • Health Sciences › Medicine › Pharmacology › Coffee research and impacts
  • Health Sciences › Medicine › Cardiology and Cardiovascular Medicine › Cardiovascular Function and Risk Factors
Keywords
cigarette smoking, caffeine, coffee consumption, aortic stiffness, arterial stiffness, wave reflection, pulse wave velocity, augmentation index, synergistic interaction, cardiovascular risk
MeSH terms
Adult, Central Nervous System Stimulants, Aortic Diseases, Blood Flow Velocity, Blood Pressure, Caffeine, Drug Synergism, Female, Heart Rate, Humans, Male, Myocardial Contraction, Pulsatile Flow, Smoking, Statistics as Topic, Stroke Volume, Cross-Over Studies

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