Study: The risk of ischemic stroke doubles after a cup of coffee
Study: The risk of ischemic stroke doubles after a cup of coffee
The following study is about examining the connection between the consumption of coffee and the occurrence of an acute ischemic stroke. The multicenter case crossover study was carried out in three medical centers and respondents 390 subjects who had suffered a stroke after their coffee consumption at an hour before the occurrence of stroke symptoms. It was found that the relative risk of stroke was doubled in the hour after coffee consumption. However, there was no obvious increase in the risk of consumption of tea or cola containing caffeine. It was also found that the connection between stroke and coffee was only observed in patients who consumed one cup or less a day, but not in patients who regularly drank more coffee. It is pointed out that the connection between coffee and stroke is more complex than often reported and that further research is required.
Details of the study:
reference
Mostofsky E, Schlaug G, Mukamal KJ, Rosamond WD, Mittleman Ma. Coffee and beginning of the acute ischemic stroke: the study at the beginning of the stroke. neurology. 2010; 75 (18): 1583-1588.
Design
Multicentric fall-crossover study
participant
The study was carried out between January 2001 and November 2006 in three medical centers (Boston, Chapel Hill and Victoria, BC). Trained interviewers surveyed 390 subjects (209 men, 181 women) on average 3 days after an acute ischemic stroke. The coffee consumption of each subject in the hour before the stroke symptoms occurred was compared with its usual frequency of consumption in the previous year.
Study "Medicines and Dosage"
The portion size for a portion of coffee was set on 8 ounces. Similar questions were asked about the consumption of caffeinated tea and cola.
primary result dimensions
In patients who have suffered an ischemic stroke, consumption and time of coffee consumption.
most important findings
78 percent of the subjects drank coffee in the previous year, 59 percent within 24 hours and 9 percent within one hour after the start of the stroke. Thus, the relative risk of stroke doubled in the hour after coffee consumption. For caffeinated tea or cola, no obvious increase in risk was found. The connection between stroke and coffee was only observed in patients who consumed ≤ 1 cup per day, but not in patients who regularly drank more coffee.
The connection between stroke and coffee was only observed in patients who consumed 1 cup of each day, but not in patients who regularly drank more coffee.
Effects on the practice
Although this study has been taken into account in public media, the connection is more complex than is usually reported. The study is only one of several relatives that have recently been published.
The time of death due to heart attack and stroke follows a circadian pattern and reaches its peak after waking up in the morning. Psychological stress, physical exertion and simply waking up affect physical parameters such as blood pressure, heart rate, blood flow, endothelial function and adrenaline level; Everyone regulates the production of sympathetic catecholamine, which increases the oxygen requirement of the heart and at the same time reduces oxygen supply. The combination leads to an increased risk of stroke in the morning. 1 The authors of the current work believe that they have designed the study in such a way that these circadian patterns do not influence their results. 10px; "> 2
Other studies provide inconsistent data on coffee consumption and to the risk of stroke. Ester Lopez-Garcia et al. reported in their work from 2009 that coffee consumption reduced the risk of stroke. They analyzed data from a cohort of 83,076 women in the Nurses' Health Study in all categories of coffee consumption. Those who drank 2 to 3 cups a day had a 19 % reduced risk of stroke (RR 0.81 (95 % KI: 0.70 to 0.95)). This connection was stronger for non -smokers. Those who drank four or more cups a day had a 43 % lower risk than those who do not drank coffee regularly.
Studies generally have also shown that drinking coffee lowers the risk of heart attack. According to a article published in August 2010, coffee was clearly associated with lower cardiovascular morbidity and mortality. In their work, 37,514 participants were observed for 13 years. Drinking 2–3 cups of coffee per day lowered the risk of heart disease by 21 %. Drinking less or more coffee had a lower protective effect.
Not all studies report on this protection. A study of Swedish coffee drinkers showed that coffee increases the risk of heart attack. Lena Nilsson et al. Compared to coffee consumption in 375 mi cases with 1,293 corresponding control persons and found a statistically significant positive connection between the consumption of filtered coffee and the Mi risk to men. If you drank coffee four times or more often, you have a 73 % increased risk of suffering a heart attack. A previous Swedish study from 2003 came to similar results in men. If you drank 10 DL (~ 4 cups), you have about twice as high risk of suffering a heart attack: a relative risk of 1.93 for filtered coffee and 2.20 for cooked coffee. If you look through these different studies, it seems as if the "toxicity dose-effect curve" of coffee could actually be u-shaped. Low and high consumers may increase the risk, while moderate consumption in the range of 2–3 cups per day can be advantageous.
There is another possible explanation for these inconsistent results. Already in the 2006 March edition of Jama , Cornelis et al. a legitimate question from the University of Toronto. Coffee does not affect everyone. Some people are very sensitive - a cup in the morning makes them sleepless all night. Others drink coffee for dinner and before going to bed, without this having negative effects. This variation is genetic. The CYP1A2 gene codes for the enzyme, which builds the caffeine. People with a version of this gene are "fast" caffeine metabolizers. Those who have a different variant are "slow metabolisers".
In the Cornelis study from 2006, drinking coffee had a different influence on the risk of heart attack, depending on whether people were quick or slow metabolisers. In slow metabolists, drinking coffee increased the risk of suffering a heart attack. For people who quickly metabolized, coffee lowered the risk:
For people who quickly metabolism due to their genes, the consumption of a cup of coffee a day reduces the risk of a heart attack by a little more than half. On the other hand, the same cup of coffee increases the risk of a slow metaboliser by about 25 %.
could it be that we are confused in the current coffee and stroke risk study and these other coffee risk studies because we do not take into account the different metabolism of the study participants? For example, in the stroke study under consideration, does it seem more likely to be that slow metabolisers belong to the group that drinks less often? People who quickly metabolism tend to drink more coffee more regularly and suffer less often from the side effects of this habit?
Although according to the study by Mostofsky et al. It is tempting to encourage patients to drink coffee regularly to reduce the risk of strokes and heart disease, it could be that more must be published for this story.