Recently Los Angeles Times reported on a UK study covering 16,000 middle-aged man and women which found a correlation between anxiety and cancer. This study lasted for 15 years and tried to give an answer to the question: Can anxiety cause cancer?
Well, it’s much more complicated than that. Getting yourself under stress can certainly cause many adverse effects on your well-being. Stress has been responsible for all kinds of diseases. But, can it ultimately lead to cancer?
Anxiety is a direct result of stress, and sometimes can have paralyzing mental effects on people.
The study found that men suffering from severe anxiety were more than twice as likely to die from cancer as those who didn’t. Interestingly, no similar connection was found in women, even though more of them fulfilled the criteria for GAD. There has been much debate over the years whether stress actually causes cancer. Researchers have suggested that people who have an inherited tendency to cancer may be more stressed because they see others in their family suffering from it (so the cancer link is causing the stress and not vice versa). It has been widely assumed that anxiety sufferers were at higher risk because they were more likely to smoke or drink to excess, and less likely to eat healthily or exercise regularly. However, this study found that even after excluding possible ‘confounding factors’ like alcohol and smoking from the equation, the connection between severe anxiety and cancer remained.
The trouble with studies like this is that they find a connection, but can’t prove that “A”actually causes “B”. Even though this study makes a stronger case for cause and effect by removing factors that might otherwise explain the connection, it doesn’t tell us howthe psychological – stress and anxiety – are directly influencing the physical. But laboratory evidence over the years can give us some clues.
– In animal studies, mice with cancer were more likely to have metastases (spread of cancer to other parts of the body) if they were subjected to prolonged stress
– Women using beta blockers, which slow the heart and can trick the body into believing it’s not stressed, have been connected with a lower chance of breast cancer spread in some studies
– Noradrenaline (norepinephrine, closely linked to adrenaline or epinephrine) has been found to increase the rate of inflammation and new blood vessel production, which in turn can promote cancer spreading
– Blood cancers are influenced by the sympathetic nervous system, which is intimately connected with adrenaline levels
– Stress can downgrade the ability of cells in the immune system to fight off invaders, including infection. Our immune system has sophisticated pathways for neutralising and destroying harmful, potentially cancerous cells, which may also be affected.
Of course, simply discovering that severe anxiety can increase the risk of cancer is enough to make anyone feel anxious. The next step is to work out what to do with that knowledge, and how to fight the connection. Unsurprisingly, laboratories across the world are hard at work translating knowledge on hormones and stress into potential new targets for cancer – but that is for the future. As yet, we don’t know whether talking therapies such as cognitive behavioural therapy (CBT) can reverse that trend. But there is very good evidence that they are powerful tools in the fight against mental illness, and can hugely improve quality of life. This latest study provides hope that the same tools might combat cancer too. And that is a pretty good start.