Abstract Body (Do not enter title and authors here): Introduction: Caffeine has been associated with both positive and negative impacts on adult athletes. However, the effects of caffeine on youth athletes have not been clearly established.

Hypothesis: Cardiac screening findings will vary by caffeine intake.

Aims: To assess the impact of different types of caffeinated drinks on youth athletes.

Methods: The HeartBytes National Youth Database produced by Simon’s Heart was used for this study. The database contains demographics, exercise-related symptoms, ECG data obtained during Simon’s Heart PPEs, and self-reported data on caffeine intake for soda, energy drinks, tea, and coffee. To investigate the effects of specific caffeinated drinks, we excluded those consuming multiple caffeine drink types from the data set and used propensity score matching to control for confounding variables of race, sex, and exercise intensity. An odds ratio statistic and p-value of 5% criterion were used to evaluate the correlation between caffeine and cardiovascular risk factors.

Results: Of the 7425 athletes in the database, the majority were male (60.6%) and White (83.1%). The mean BMI was 21.4 (SD 4.6). The median age was 15.0 years old (IQR 13.5-16.5). Of 1864 athletes taking caffeine drinks, 685, 43, 617, 246 drank only soda, energy drinks, tea, and coffee respectively. Athletes drinking soda had higher odds of diabetes (p=0.041), ADHD (p<0.0001), anxiety or depression (p=0.004) and obesity (p=0.018), but lower odds of asthma (p=0.011) if exercising more than 10 hours/week. Athletes drinking energy drinks had higher odds of hypercholesterolemia (p=0.021) if exercising less than 5 hours/week, and higher odds of murmur if exercising more than 10 hours/week. Athletes drinking tea had higher odds of hypertension (p=0.043), exertional dyspnea (p=0.019), ECG right ventricle hypertrophy (p=0.021), and higher odds of ECG nonspecific ST wave abnormality (p=0.04) if exercising more than 10 hours/week. Athletes drinking coffee had higher odds of exertional syncope (p=0.001), and higher odds of ECG T wave inversion (p=0.038) if exercising more than 10 hours/week.

Conclusion: Overall, both tea and coffee drinkers were at higher risk of ECG abnormalities, with higher risk of hypertension and exertional dyspnea in tea drinkers. Coffee drinkers also had higher risk of exertional syncope. Soda drinkers were at higher risk of diabetes and obesity. Further studies are needed to delineate long-term effects of caffeine consumption on youth athletes.