Heart disease from smoking and drinking starts in teens
Smoking and drinking damage our hearts and blood vessels. But when does the damage begin to set in? New research following teenagers suggests that, as early as age 17, there may already be signs of disease developing. Adam Murphy spoke to the study’s author, John Deanfield from University College London.
John - My interest is in understanding how arterial disease develops in all of us that eventually in many of us unfortunately, leads to heart attacks and strokes in later life. Despite the fact that these clinical problems occur usually in our 50s and 60s. What we've learned is that the underlying arterial disease starts decades earlier and it often starts in teenagers and young adults.
Adam - And what happens in these young people? how do we know that the disease is starting?
John - So we use an ultrasound based technique where we image the artery and we look at the response to blood flow in the artery and how the artery moves when the blood is going down in response to the heart beat. And there is this formula you can apply to see how adaptable the arteries are to changes in blood flow and pressure and that represents a stiffness index and when you damage your arteries the first thing you do is to damage the lining of the arteries. The second thing that happens is the artery as a consequence becomes much more stiff and rigid and that's a beginning of a process that eventually leads to clinical problems in later life.
Adam - How did you find this in these young people?
John - So what we did was to study a group of young people who are part of a very big longitudinal study started in Bristol when they were born and that's called the ALSPAC study. And what we did was to take the children who had been following up and look at their arteries and look at the function of their arteries in relationship to two very important potential factors that might relate to heart disease and that is smoking and alcohol consumption. Now we looked at smoking by looking how many cigarettes they had been exposed to in their life and alcohol we looked at in a little bit more detail looking at the pattern of drinking in terms of not only how often they were drinking but also to see what happened when they drank in a sort of intensive way in a binge drinking way on one day for example which is the common pattern often in young people and we were able to show that the smoking even at very low levels was associated with signs of arterial damage. Alcohol consumption was associated with signs of arterial damage but it was particularly the binge drinking that was bad for the arteries but when the young people both smoked and drank alcohol in that way the arterial damage was added on, it was cumulative. So it was much worse to drink and smoke than it was to smoke early and drink heavily. But all of those factors were already showing signs of damage to the arteries in teenage years which is very early on.
Adam - What is the impact for their later life? And is there any chance of recovery from this?
John - So that's a really good question. We now know from lots of studies that the disease that eventually causes so many problems in later life starts early and that it is progressive with time and it is the exposure to risk factors over time that drives the development of arterial disease. Now if you were to take an elderly person who's already got established arterial disease and try to reverse the problem you'd be disappointed because those accumulated diseases are largely irreversible and we have to deal with them with complex and expensive interventions like stents or operations to bypass them. But at the young age potentially the disease is reversible and that's what we've got a clue for in this study as well because we looked at the arteries of the young people who'd stopped smoking, their actual function was the same as the young people who had never smoked. Potentially these early damages are reversible by stopping smoking early and I think that's a very positive message from this study.
Adam - Do we know when it stops being reversible, when the arteries can't bounce back anymore.
John - There probably isn't a magic time a young person who smokes continuously from their thirties loses on average about a decade of life expectancy. That's a huge amount of life lost but if you stop at 30. The good news is you regain about 90 percent of that if you stop when your 50s and 60s you regain around 40 per cent only. So there’s everything to gain by stopping early.
Adam - If you could have people take one thing away from this study what would you want them to take from it?
John - Never smoke cigarettes. The effect of cigarette smoking is much greater on arterial health in the future than alcohol consumption. Smoking is always bad. It really is a crazy thing to do for a young person who wants to have a healthy future.