Caffeine Does Not Increase Risk for Arrhythmias, PVCs, or PACs
Moderate caffeine consumption does not increase the risk of arrhythmias, PVCs, or PACs in patients with or without pre-existing heart conditions, and may actually be protective against certain arrhythmias.
Evidence from Guidelines and Clinical Practice
General Population and Patients with Known Arrhythmias
Exercise-induced supraventricular arrhythmias are not related to coronary artery disease but are more often associated with older age, pulmonary disease, recent alcohol ingestion, or excessive caffeine intake 1. However, this refers to acute excessive intake, not habitual moderate consumption.
The American Heart Association guidelines note that caffeine increases blood pressure and heart rate, increases susceptibility to cardiac arrhythmias, and may interfere with diabetes control 1, but this statement appears in the context of perioperative supplement management and refers to high-dose caffeine supplements, not typical coffee consumption.
Stimulant use, particularly caffeine present in dietary and workout beverages and powders, should be queried and considered in competitive athletes with hypertension, symptomatic palpitations, or documented ectopy or arrhythmias 1. This recommendation targets energy drinks and concentrated caffeine products, not regular coffee or tea.
Specific Arrhythmia Types
Acute ingestion of caffeine (as coffee or tea) does not cause atrial fibrillation 2. Even patients suffering myocardial infarction do not have increased incidence of ventricular or other arrhythmias after ingesting several cups of coffee 2.
Large epidemiologic studies have failed to find a connection between the amount of coffee/caffeine used and the development of arrhythmias 2. Therefore, it does not make sense to suggest that patients with palpitations, paroxysmal atrial fibrillation, or supraventricular tachycardia abstain from caffeine use 2.
Moderate ingestion of caffeine does not increase the frequency or severity of cardiac arrhythmias in normal persons, patients with ischemic heart disease, or those with pre-existing serious ventricular ectopy 3.
High-Quality Research Evidence
The Most Recent and Highest Quality Study
The 2021 UK Biobank prospective cohort study of 386,258 individuals found that each additional cup of habitual coffee consumed was associated with a 3% lower risk of incident arrhythmia (HR 0.97; 95% CI 0.96-0.98; P<0.001) 4. This protective effect was observed for:
- Atrial fibrillation/flutter (HR 0.97; 95% CI 0.96-0.98; P<0.001) 4
- Supraventricular tachycardia (HR 0.96; 95% CI 0.94-0.99; P=0.002) 4
Mendelian randomization analysis in this same study revealed no significant association between genetic propensities to different caffeine metabolism rates and risk of incident arrhythmia 4, indicating that individual variations in caffeine metabolism do not modify arrhythmia risk.
Supporting Evidence
In five placebo-controlled trials, caffeine in doses up to 500 mg daily (equivalent to 5-6 cups of coffee) did not increase the frequency or severity of ventricular arrhythmias 3.
In most patients with known or suspected arrhythmia, caffeine in moderate doses is well tolerated and there is no reason to restrict ingestion of caffeine 5.
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-analyses 6.
Important Caveats and Clinical Pitfalls
Energy Drinks Are Different
Energy drinks loaded with caffeine, sugar, and other chemicals can stimulate the cardiac system, with increasing anecdotal case reports describing arrhythmias or even sudden death triggered by exercise plus energy drink use 2. It is wise to either limit or avoid their use in patients with arrhythmias 2.
Caffeine Withdrawal vs. Consumption
Patients who are caffeine-dependent may experience withdrawal symptoms including headache and fatigue, which should not be confused with arrhythmia symptoms 1. The concern about "caffeine dependence" mentioned in perioperative guidelines 1 relates to withdrawal management, not arrhythmia risk.
Dose Matters
- One large epidemiologic study reported an increase in ventricular extrasystoles only in persons consuming 9 or more cups of coffee daily 3
- Moderate consumption (up to 5-6 cups daily) has consistently shown safety 3
Clinical Recommendations
What to Tell Patients
Patients with arrhythmias, PVCs, or PACs do not need to limit regular coffee or tea consumption 2, 5. There is no real benefit to having patients with arrhythmias limit their caffeine intake 2.
What to Avoid
- Discourage energy drinks, particularly in combination with exercise 2
- Avoid high-dose caffeine supplements or concentrated caffeine products 1
- Consider caffeine intake only when patients report consuming >9 cups of coffee daily 3
When to Investigate Further
If a patient reports palpitations or arrhythmias temporally related to caffeine, investigate for other triggers including alcohol use, which is actually associated with arrhythmias (particularly the "holiday heart" phenomenon with binge drinking) 1, 2.