An interesting case study has been written up and released that details the story of a patient who was sent to the hospital due to cardiac complications and vomiting blood—it apparently may have been caused by caffeine from energy drinks.
As far as the hierarchy of evidence goes, a case study is basically a well-written anecdote, but the story is intriguing enough to look over even if its weight is low in the grand scheme.
The patient in question was a 28-year-old obese man who was brought to the emergency department after the above-mentioned bloody vomit. He was given an examination and, other than his weight, the only abnormality was that his heart rate was at 130 beats per minute. In the average adult, the normal heart rate when at rest is somewhere in the 60-100 range. Further testing revealed that the man had atrial fibrillation, a type of abnormal heart rhythm.
Medication was able to resolve the fibrillation after two days and restore a normal heart rate. Other than some tears in the esophagus and stomach from the vomiting, no other damage was sustained. When questioned, the patient said that he routinely drank two Monster-brand energy drinks each day along with up to three beers. According to the doctors, no other potential cause for the atrial fibrillation was apparent.
Doctors believing that the energy drink consumption played a key role due to the high levels of caffeine involved. A single Monster contains around 160 mg of caffeine, four times that in a normal caffeinated soft drink. There is some evidence in past research that has linked energy drinks to cardiovascular events and in one notable event, even a death.
Most of these past events have either not been conclusively linked to the use of energy drinks, involved people who had pre-existing heart conditions, or who were mixing energy drinks with alcohol or drugs.
Based on past evidence, the doctors believe that it was the routine high caffeine intake from the man’s energy drinks that caused his cardiac complications. Since this was a case study and not an experiment, there is no way to say how valid the suspicions are. Whether any actions will be taken to investigate further remains to be seen.
“Energy Drink Consumption and Cardiac Complications: A Case for Caution,” Journal of Addiction Medicine, the official journal of the American Society of Addiction Medicine (ASAM); http://journals.lww.com/journaladdictionmedicine/Abstract/2016/08000/Energy_Drink_Consumption_and_Cardiac.11.aspx.