Cannabis use can cause palpitations

Does marijuana increase the risk of cardiac death?

ATLANTA. The number of cardiovascular deaths has steadily declined over the past decades in almost all industrialized countries, adjusted for age. This trend seems to have been reversing in the USA since 2011: Since then, a slight increase in cardiovascular mortality has been observed again.

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Foggy researcher brains?

This was also expected by experts, as more and more people in the USA are suffering from the consequences of obesity and diabetes.

More marijuana users

But other lifestyle changes could also favor heart and brain attacks. Although fewer and fewer people are smoking, the proportion of marijuana users is increasing at the same time, as the legal regulations have been relaxed in many countries.

Epidemiologists working with Barbara Yankey from Georgia State University in Atlanta suspect that this trend could also have an adverse effect on cardiovascular mortality.

In addition to the harmful effects of smoking itself, the active ingredient THC in hashish may also damage the heart and brain directly. For THC consumption, for example, an increased pulse rate, increased blood pressure, increased cardiac output, reduced left ventricular ejection time and an increase in venous CO2Values ​​confirmed, write the scientists working with Yankey (European Journal of Preventive Cardiology 2017, online August 9).

Data from 5000 Americans

Using data from the annual representative lifestyle and nutrition survey NHANES, the epidemiologist's team looked to see whether there was an increased cardiovascular mortality among hashish consumers.

To this end, the researchers evaluated the results of the 2005 survey of around 5000 Americans. At that time, the participants were also asked for the first time whether they had consumed cannabis before. Anyone who admitted to having smoked hashish or marijuana at least once in their life was considered a cannabis user.

Participants were also asked to indicate when they first started taking the drug. The years from the first consumption to the survey were quantified as consumption years.

So if you smoked a joint at the age of 18 and never again after that, then, according to this reading, you had 20 years of use under your belt if you took part in the survey at the age of 38. Another problem is of course that the information was voluntary. The number of unreported cases should have been quite high.

Death rate increased by 29 percent

Now the US epidemiologists looked at how many of the avowed cannabis users and those who had denied cannabis use had died six years later from what. To do this, they evaluated death certificates that were kept in various registers. They were particularly interested in cardiac, cerebrovascular and hypertension-related causes of death (ICD codes for "essential hypertension" or "hypertensive kidney disease").

A total of 1213 participants from the 2005 survey answered the question about cannabis use - that is, only a quarter of the respondents at all.

At the time of the survey, the participants were on average 38 years old and stated a BMI of 29. Almost 57 percent answered "yes" to the cannabis question - they were therefore considered consumers.

A quarter currently smoked tobacco, a fifth had smoked before, and just under 18 percent used risky alcohol consumption. 34 percent had smoked neither tobacco nor cannabis, 21 percent had tried marijuana before but were not smokers. The average marijuana use was around twelve years ago.

In 2011, 332 participants died (27.4 percent). The death rate among cannabis users was 29 percent higher than among those who did not admit drug use, but the difference was only marginally significant. For tobacco smokers, however, there was no significantly increased death rate.

According to the death certificate, 13.7 percent of avowed marijuana users died of hypertension-related causes, but only 9.4 percent of participants without cannabis use. However, cardiac and cerebrovascular deaths were similarly common.

Unreliable database

From the raw data, the hypertension-related death rate was not significantly increased, but if the researchers took into account pre-existing cardiovascular diseases, BMI, insurance status, alcohol and cigarette consumption, they came to a 3.4-fold higher mortality risk for hypertension-related causes of death among marijuana users.

However, it can be seriously doubted that such arithmetic games have any relevance. The study seems to combine pretty much every imaginable bias.

On the one hand, the voluntary information on marijuana use can be trusted just as little as the information on death certificates - both are known to be very unreliable, which means that the database of the study is quite useless.

Furthermore, the extent of cannabis use is not taken into account. Anyone who had tried hashish even once was assumed to have continued to use it. However, this is not realistic: only a small proportion of the population regularly uses illegal drugs.

So it can hardly be assumed that 55 percent of Americans are permanently stoned, as suggested by Yankey's team.

Details of only 28 death certificates

After all, the numbers are too low for reliable statements. Ultimately, only 28 participants who had ever tried cannabis had a hypertension code on their death certificate.

Last but not least, the results for tobacco smoking should make you suspicious: There were no negative effects here, on the contrary, hypertension and heart disease tended to be noted less frequently on the death certificates of current smokers than among non-smokers.

"This is an exploratory study and a first step towards understanding the link between marijuana use and cardiovascular deaths."

And further: "Now progress studies would be necessary to see whether such a connection with security exists", explained Yankey - when asked about the shortcomings - to the "Ärzte Zeitung".