PARIS, August 30 (Benin News) –
The risk of death or poor prognosis after a heart attack is more than 20 times greater in smokers with exhaled carbon monoxide levels above 13 ppm, indicating heavy smoking and smoke inhalation, according to a study. study presented at the ESC 2022 congress of the European Society of Cardiology.
“The amount of carbon monoxide in the breath is directly related to the number of cigarettes smoked, but also to the way you smoke,” says lead researcher Professor Patrick Henry, from Lariboisière Hospital in Paris, France. .
“Individuals may inhale the smoke deeply or not at all, and they may smoke cigarettes from start to finish or leave them burning in the ashtray,” he explains. Finally, where you smoke can play a crucial role, as smoking in a small, unventilated room is likely to increase carbon monoxide levels compared to smoking outdoors.
Burning cigarettes produces carbon monoxide, a highly toxic gas that is also found in motor vehicle exhaust, pollution and faulty heaters. Carbon monoxide replaces oxygen in the blood and can be fatal.
Professor Henry notes that “patients suffering from acute cardiac events, such as heart attacks, do not have enough oxygen in their coronary arteries. Our hypothesis is that if some of the oxygen is replaced by carbon monoxide, the event may be more serious.
During a two-week period in April 2021, expiratory carbon monoxide was measured within two hours of admission in all consecutive adults hospitalized for acute cardiac events in 39 cardiac intensive care units (CICUs) in France. A total of 1379 patients were studied. The average age was 63 years old and 70% were men. Regarding the reason for admission, 720 (52%) patients had acute coronary syndrome, 186 (13%) acute heart failure and 473 (34%) other acute heart disease. The median stay in the intensive care unit was five days.
Patients were asked about their smoking status. A third of the participants (33%) were non-smokers, 39% were ex-smokers and 27% were current smokers. Carbon monoxide levels were similar in non-smokers and ex-smokers (mean 3.6 and 3.3 ppm, respectively) and significantly higher in active smokers (mean 9.9 ppm).
The researchers analyzed the association between carbon monoxide level and the primary outcome of major adverse events in hospital, which was a composite of death, resuscitated cardiac arrest or cardiogenic shock. A total of 58 patients (4.2%) experienced a major adverse event during their hospital stay.
Carbon monoxide level was significantly associated with serious adverse events in active smokers, with an odds ratio of 1.14 per ppm unit, meaning that for every one ppm increase in carbon monoxide, the risk event was increased by 14%.
They identified 13 ppm as the best threshold for predicting a worse prognosis. Smokers with carbon monoxide levels greater than 13 ppm were 23 times more likely to experience a serious adverse event than those with carbon monoxide levels less than or equal to 13 ppm, after adjusting for factors likely to influence the relationship, such as age, gender, diabetes, smoking, history of cardiovascular disease, chronic kidney disease, history of cancer, and reason for admission.
Among smokers with carbon monoxide levels of 13 ppm or less, the rate of major adverse events was similar to that of non-smokers or former smokers. Nearly one in five active smokers (19%) had carbon monoxide levels above 13 ppm, compared to less than 2% of non-smokers or ex-smokers.
“Our study shows that when a smoker is hospitalized for an acute cardiac event, a carbon monoxide level above 13 ppm is associated with a worse prognosis,” says Dr. Henry. We also found that carbon monoxide levels were a much stronger predictor of adverse events than smoking status.
“The results suggest that exhaled carbon monoxide could be measured in cardiac patients on admission to better assess their prognosis,” he says. Carbon monoxide poisoning is treated with high flow oxygen which quickly reduces dangerous levels in the blood. Further research is needed to determine whether this therapy might improve the post-heart attack prognosis of smokers with carbon monoxide levels above 13 ppm.