Quitting smoking; why have a lung CT scan

Posted in , by Sophia Daly

We all know smoking is a bad habit; it can be a comfort particularly in high-stress careers but it can result in a lung cancer diagnosis. Recently the Covid-19 pandemic has put an extra emphasis on lung health, with this survey in the Chinese Medical Journal for instance finding smokers are 14 times more likely to develop severe cases if infected.

If you smoke, quitting is the most powerful choice you can make for your health, reducing your risk of The Big Four – namely cancers, lung disease, heart disease and stroke.

There are numerous health benefits which continue to accumulate as your last smoke becomes a distant memory. Nevertheless, it’s always a good idea for ex-smokers to undertake a full medical check, including a lung CT scan. Even if you’re asymptomatic, as an ex-smoker you are predisposed to various illnesses and early detection could save your life.

Pack years

A common metric to use to determine risk is Pack years where Pack years = the number of packs of cigarettes smoked per day multiplied by the number of years a person has smoked

Your risk of developing one or more of the big four is heavily influenced by your pack years. Several studies (such as this one in the peer reviewed site PLOS ONE) have found that pack years are more strongly associated with the risk of developing  lung and heart disease than whether or not a person currently smokes.

How does tobacco smoke cause disease?

  • Lungs – tobacco smoke contains many carcinogens – cancer causing agents – which cause DNA mutations leading to cancer. Tar damages tiny structures called cilia that protect the lungs, leading to increased risk of lung infections. It also damages the small air sacs called alveoli, causing irreversible emphysema or chronic obstructive pulmonary disease (COPD).
  • Inflammation – nicotine causes inflammation, which essentially means ‘general swelling’. This dampens the immune system preventing it from effectively staving off infection and cancer, and it changes our blood glucose and circulation to organs like the stomach. This is why smokers are at an increased risk of diabetes and stomach ulcers.
  • Heart and blood vessels – nicotine also causes heart rate and blood pressure to increase, putting strain on vessel walls, weakening them. It increases the risk of blood clots and encourages the build-up of plaque (‘furring up’), known as atherosclerosis. Therefore, smoking is a major cause of coronary heart disease, heart attacks and strokes.
  • Cancer – Those nasty carcinogens enter the bloodstream where they also affect the cells of organs far from the lungs, causing increased risk of other cancers, including colon, liver, pancreas, kidney, bladder, oesophageal. Indeed, smoking is thought to be the cause of almost half of the 12 most common cancers.
Lung cancer diagnosis - lung CT scan blog - Echelon Health
Cigarette smoke contains many carcinogens which damage DNA and result in lung cancer diagnosis

The sooner you quit smoking the better chance you have of recovering from these effects of cigarette smoke. Not only that, but there are some early benefits too. To give you that bit more extra motivation, here is the Echelon Health time line guide to the benefits of quitting smoking:

Time since your last cigarette

12 hours

  • Heart rate and blood pressure are now normal. Short-term inflammation decreases. Circulation will improve as constricted blood vessels relax.
  • Nicotine levels have reduced significantly, so have those of carbon monoxide. Carbon monoxide is a toxin in cigarette smoke which prevents oxygen from binding to haemoglobin in the red blood cells in our lungs, causing a lack of oxygen and a shortness of breath.

3 days

  • Your risk of a heart attack begins to decrease as your blood pressure decreases.
  • You may notice a heightened sense of smell and taste as your respiratory tract clears of tobacco smoke and the nerve endings here begin to heal.
  • However, as your body is now free of nicotine, withdrawal symptoms will peak. So be prepared for the onset of irritability, bad headaches and cravings. Remember this is temporary – don’t give in.
  • Male fertility will already be improved as new sperm are not exposed to the toxins in tobacco smoke. Meanwhile, if a woman quits before she is pregnant, the risk of her baby being born prematurely is reduced to that of a non-smoker.

1 month

  • The cycle of addiction is now largely broken and the nicotine receptors in your brain return to normal – so the cravings should be much reduced.
  • Coughing and shortness of breath subside whilst energy and ability for cardiovascular activities increases. The lungs are healing.
  • Tiny hair-like structures known as cilia begin to regrow. These line your lungs and are very important. In a healthy lung, cilia beat up and down sweeping mucus up and out of your lungs to prevent build-up and infection – and bacteria and toxins along with it. This means a reduction in lung infections.

1 year

  • Your risk of coronary heart disease is now half of what it was as a smoker – and this continues to decrease.
  • Your risk of stroke is reduced to half that of a smoker.

5 years

  • If you’ve been taking better care of your overall health, your arteries and blood vessels may recover from atherosclerosis. This cuts your risk of a stroke to half that of a smoker.

10 years

  • As your circulation is improved, blood flow to the gums and teeth is also more efficient. Your risk of developing gum disease has dropped to that of a non-smoker.
  • Your chance of developing cancer of the lung, mouth, throat or voice box is cut in half compared with smokers.
  • The risk of cancers of the pancreas, kidney, cervix and bladder have all significantly reduced.
  • In fact, if you haven’t succumb to smoking-related disease, you can expect to live ten years longer than a smoker.

15 years

  • Your risk of coronary heart disease and pancreatic cancer is equivalent to that of a non-smoker.

Should ex-smokers be worried about their health?

Echelon Health recommends:

  • Develop a health coping mechanism – something stimulating like a crossword, a morning run or a new hobby. The last thing you want is to satisfy your fidgets with an affinity for the cookie jar. Keeping your overall health in mind is key.
  • Reduce stress and get a good nights sleep – try relaxation exercises like meditation and yoga
  • Eat healthily and exercise – use your renewed palette to appreciate a colourful nourishing diet.
  • Start a regular exercise program – it will be tough to start with, so begin gently and gradually increase duration and intensity. Make these a fixed time in your weekly schedule, as it is always easy to make an excuse not to do it.
  • Don’t take up vaping – this is a slippery slope and you know it! E-cigarettes contain nicotine too which is bad for your lungs and heart.
  • Get a full medical – including a low-dose lung CT scan, to ensure you are in the clear and that anything worrisome is detected early

In summary, it is still advisable for an ex-smoker to do all they can to improve their health. Quitting smoking is impactful. But to truly recover from the damage of cigarette smoke you need to be on a long-term sustainable health journey.

Couple jogging
Exercise is one of a number of lifestyle habits that will help your body recover from the damage caused by smoking

Why have a lung CT scan?

Early detection of disease vastly improves the outcome. Even if you are asymptomatic, as an ex-smoker you are at an increased risk of The Big Four. Yes, your likelihood of developing one of these diseases – cancers, lung disease, heart disease or stroke – does decrease over time, but only if you don’t develop one in the meantime. Having a full medical check up will put these worries to bed – or if indeed something is detected, you will have a promising outcome and a team of experts ready to support you at Echelon Health.

Additionally, depending on your pack years you may have accumulated some permanent lung damage – two common causes of smoking-related deaths are chronic obstructive pulmonary disease (COPD) and pulmonary fibrosis. It is important to detect these early.

You may be reading this as someone who has never smoked thinking none of this applies to you. Sadly, this may not be the case as lung cancer isn’t just a smoking disease. According to LungHealthUK.com. whilst 86% of lung cancer cases in the UK are due to smoking, not smoking is no guarantee.  In recent years the proportion of lung cancer in non-smokers, particularly women, has significantly  increased for reasons which are not yet clear, so the benefits of lung screening can also be extended to non-smokers..

Early detection and prevention of disease are at the heart of Echelon’s philosophy. Our experts will assess you as an individual using a suite of top-of-the-range scanners to perform a personal health assessment – which we believe is the best health check up in the world. We are collaborative, focused and use the most comprehensive scanning techniques to detect those diseases which cause premature death.

lung CT scan - lung disease - Echelon Health
A CT scan is the superior screening modality for imaging the lungs

Why is a lung CT scan the best for a lung cancer diagnosis?

The American Cancer Society recommends an annual low-dose lung CT scan for people at a higher risk of developing lung cancer. This includes those who smoke or have quit in the past 15 years and there is good reason for this recommendation.

A CT machine has far better resolution than an x-ray, which can only detect tumours of 10mm in size. Here at Echelon Health using our low dose modern CT scanner, our experienced chest radiologist has detected lung cancers as small as 1-2mm.

Meanwhile an MRI scanner cannot be used for lung cancer screening or high resolution imaging of the lungs, as it works better on denser tissues with more water and fat. The lungs, being as they are an air cavity, are not imaged as well on an MRI.

Is a CT scan safe? In one word yes. The radiation dose of a chest CT scan or CT coronary angiogram is equivalent to spending just a few weeks in Cornwall – due to its higher natural background radiation Nevertheless, we appreciate that in rare circumstances, CT may not be ideal. Rest assured that our experts consider your individual needs before any tests or examinations take place.

To read more about why we use CT, click here 

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CDC (Centre for Disease Control) – Cancer and Smoking

How tobacco smoke causes disease – CDC 2010

Gov.uk – Smokers at greater risk of severe respiratory disease from COVID-19

Push Doctor – Stop Smoking Timeline