For those who enjoy a drink to relax during long flights, here's some troubling news: researchers have discovered that in-flight alcohol consumption raises heart health risks, even for young and healthy individuals.
The reduced cabin pressure experienced at cruising altitude creates a hypobaric environment, which is known to increase heart rate. A hypobaric environment can sometimes aggravate cardiac symptoms in individuals with pre-existing cardiopulmonary diseases, particularly in sleep.
A recent study published in the BMJ journal Thorax examined the combined impact of hypobaric hypoxia (a condition of low oxygen concentration at high altitudes) and alcohol consumption before sleep in healthy individuals.
"Even in young and healthy individuals, the combination of alcohol intake with sleeping under hypobaric conditions poses a considerable strain on the cardiac system and might lead to exacerbation of symptoms in patients with cardiac or pulmonary diseases," the researchers wrote.
The researchers made the findings after evaluating 48 healthy adults who were randomly assigned into two groups: one group slept under sea-level air pressure conditions, while the other group slept in an altitude chamber simulating the air pressure experienced during cruising on flights. Within each group, half of the participants slept after consuming alcohol, while the remaining half did so without consuming alcohol.
The trial was repeated two days later when the participants who had earlier consumed alcohol before sleeping were put to sleep without alcohol and vice versa.
The researchers noted that individuals who consumed alcohol at sea level before sleeping saw a blood oxygen saturation drop to 95%, with their heart rates rising to 77 beats per minute. However, those who consumed alcohol before sleeping in the altitude chamber experienced a decrease in blood oxygen saturation to an average of 85%, accompanied by an increase in heart rate to nearly 88 beats per minute.
"We conclude that the combined influence of alcohol and reduced atmospheric pressure has a supra-additive effect and even young and healthy participants suffered from clinically relevant desaturations (SpO2 <90%) and heart rate accelerations during sleep," the researchers wrote.
The normal oxygen saturation saturation should be between 95% to 100% for healthy adults.
"Our findings support the recommendations of the BTS Clinical Statement on Air Travel to avoid alcohol in the 12 hours preceding and during air travel when suffering from obstructive sleep apnea syndrome or obesity hypoventilation syndrome. Moreover, public awareness of this topic should be raised through patient charities, public campaigns, and written health advice of airlines. Technical and economic constraints make it unlikely that an increase in cabin pressure will be implemented by airlines," the researchers wrote.
