Booze, Birth Control, and Blood Clots

We’ve been writing a lot about hormonal birth control and the risk for blood clots lately. We think the connection between hormonal birth control and blood clots is significantly under-recognized, especially in young women who, for all intents and purposes, are healthy. Perhaps it’s the marketing of these medications as lifestyle drugs, something we need as modern women to control our unruly bodies, or perhaps, it is the drug labels themselves that assure us only overweight, over 35 year old smokers are at risk for blood clots, whatever the reason, most of us have decided that we are not at risk. In doing so, not only do we not recognize the early signs of impending trouble but we fail to appreciate how other lifestyle choices, even healthy ones, can exacerbate those risks and make it all but inevitable that clots will emerge at some point with long term hormonal birth control use.

With athletic women in particular, the number of blood clot risk factors stacks up pretty quickly just in the course of everyday training, I wrote about the risks Blood Clots, Birth Control and Female Athletes: Are We Missing Important Risk Factors? A colleague of mine, wrote about how clots form and the risks in non-athletic women. And we have begun to publish personal stories from survivors of hormonal contraceptive induced blood clots and from the families who were not so fortunate and lost their loved ones. As we dig deeper into the stories, more connections bubble to the surface, like the one between female athletes and blood clots. Who would have considered that healthy, young female athletes would be at a higher risk than non-athletic women? Not many, but indeed, they may be.

Booze and Blood Clots

Another connection, not formerly recognized might be alcoholic intake. We all recognize the myriad of health risks associated with heavy alcohol intake both chronic and in binge form. What is not recognized as fully are the complex hematological changes associated with alcohol intake. With long term heavy drinking, thrombocytopenia or excessive bleeding is prominent, but with lesser amounts alcohol intake the opposite may occur. It appears that alcohol’s effects on bleeding and clotting vary by dose (how much you drink at a time) and chronicity (how frequently and consistently you drink), and perhaps even by type of alcohol ingested (hard alcohol versus beer versus wine).

Currently, the predominant dogma suggests that regular light drinking may be protective and good for our long term health. This may or may not be the case. A recent study found that regular, light drinking (defined as 2-4 drinks per week) reduced the risk for heart attack or stroke in men.

In contrast, however, any long term protection conferred by light drinking does not include the first 24 hours or so after one drinks. In the hours immediately following light alcohol intake, a cascade of biochemical changes occur that make one more disposed to heart attack or stroke, presumably via increased clotting mechanisms (alcohol intake increases platelet aggregation initially before decreasing and altering platelet structure and function to bleeding over clotting). It seems that compensatory mechanisms may come into play to counteract the short term increase in clotting. In contrast, heavy drinking (6-9 drinks), the risk for stroke and heart attack continues for the entire week (maybe longer).

‘Just after drinking, blood pressure rises and blood platelets become stickier, which may increase the risk of having a heart attack or stroke, but regular moderate alcohol consumption is associated with higher HDL cholesterol and reduced blood clotting, which may decrease risk,’ Mostofsky said.
However, heavy alcohol drinking was associated with higher cardiovascular risk in the following day (six to nine drinks) and week (19-30 drinks).

Of course, the many of the studies cited were conducted using males, as are most studies of this sort, but let us consider what the impact of drinking might be on a woman, who uses hormonal contraceptives and who may be an athlete and/or have other conditions that predispose her to clotting.

With Birth Control As the Backdrop, Blood Clots Are Imminent

Remember, from our previous posts that the balance between clotting and bleeding is altered significantly in favor of clotting when a woman uses hormonal birth control. In fact, pro-clotting factors increase by some 170% while anti-clotting factors diminish by 20% with hormonal contraceptives. Those changes by themselves are concerning. If in the hours after one drinks alcohol, additional pro-clotting factors are increased, we can imagine that the risks for blood clots might be especially high for women who use hormonal birth control.

Now consider a female athlete, using birth control, has few drinks post competition to celebrate before boarding a bus, train, or plane for a long trip home. That combination of variables which are entirely commonplace in the life of the female athlete, combine to form an incredibly high risk for blood clots. Similarly, binge drinking on college campuses, even amongst athletes has become increasingly common. The combination of alcohol related clotting changes (in addition to all of the other unhealthy aspects of drinking) and birth control related changes in coagulation, could be deadly.

What the actual numbers are for these possibilities, no one knows. Research protocols are, more often than not, designed to address only a few variables. I am not aware of any that have addressed the cascade of variables associated with blood clots in female athletes, let alone blood clots in female athletes who drink moderately, or conversely, the effects of alcohol on blood clotting in women who use birth control. What we do know is that hormonal birth control changes blood chemistry in such a way that pro-clotting factors are increased by almost 3X their normal values. That’s troubling. When we add any number of other real world risks that also increase ones propensity to clot, the results can be devastating. If you must use hormonal birth control, perhaps avoiding alcohol is in order. Although, I would argue that before you decide to use hormonal birth control, especially if you are an athlete, consider your health risks carefully. Do your homework and then make a decision.

For the Men

Clotting is a problem not just for women who use hormonal birth control. Men also develop blood clots, especially male athletes, particularly those who have to travel long distances between competitions and now, as we can see, especially those who have a few celebratory beers post competition. Even though that beer tastes fantastic after a race, perhaps if one has a long trek home, it might be wise to postpone the celebration until one’s body recovers and the prospect of sitting immobile for hours has passed. That first 24 hours post alcohol consumption seems to be the most risky. This coincides directly with the increased risk for clotting post training or competition, add immobility to the mix and all sorts of problems are likely to arise. Keep your man safe, celebrate when you get home.

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Photo by Kelsey Chance on Unsplash.

This article was published originally on March 17, 2016.