Effects of mental illness on cancer death rate
Depression and anxiety often also affect the physical health of those affected. Researchers have now found that mental illness increases the risk of dying from some forms of cancer by a third.
A team of scientists from University College London, Edinburgh University and the University of Sydney found that depression and anxiety greatly increased the likelihood of cancer death. The doctors published the results of their study in the British Medical Journal (BMJ).
One in ten people in Britain with anxiety and depression
In the UK alone, about one in ten people experience anxiety or depression at some point in their lives, the authors say. The new research is now examining for the first time the effects of mental illness on mortality from colorectal, prostate and pancreatic cancer, the experts report.
Depressed people often do not move enough and smoke and drink more often
For example, one reason for the increased death rate could be that depression makes it more likely for those affected to start smoking or drinking, the doctors suspect. In addition, most of those affected by depression have too little exercise.
Emotional hardship can affect immune functions
Anxious and depressed people die more often from cancer. This effect suggests that bad luck and dissatisfaction weaken the body's defense system against the disease. Emotional hardship can affect immune functions and damage DNA repair, the authors say.
Depressed people are less likely to be properly treated
Depression can also cause people to miss screening for cancer. In addition, the occurrence of fears and depression often prevent the sick from starting the right treatment at all, the experts report.
Anxiety and depression increase the risk of cancer death by 32 percent
In the study, the doctors checked the data from 16 different studies. These contained the data of more than 163,000 people from Great Britain. The researchers found that anxiety and depression increased the risk of cancer death by 32 percent. This result was independent of the age, gender, education, weight and status of those affected. Smoking and alcohol consumption also had no effect.
Mortality rate increased significantly in some forms of cancer
After statistical control of these factors, the results showed that the death rate in the most stressed group for cancers of the intestine, prostate, pancreas, esophagus and leukemia was significantly increased compared to the control group.
Medically monitored for a period of almost ten years
The subjects were medically monitored for almost a decade. With the help of questionnaires, they should assess whether they were anxious or depressed. For some types of cancer, mental wellbeing was as important to the death rate as the influence of obesity or smoking, the experts say.
People with depression and anxiety often neglect their health
People with mental health problems often neglect their health. This could explain the increased death rate in colorectal, pancreatic and esophageal cancer, the scientists speculate. All of these diseases are related to the lifestyle of those affected. These types of cancer can worsen if people with mental health problems exercise or eat unhealthily and overeat, the scientists emphasize.
Hormone released during depression could affect cancer mortality
Prostate cancer is another form of cancer that leads to increased mortality rates in people with emotional problems. Prostate cancer is linked to a special hormone. The increased mortality rate could be influenced by the so-called stress hormone cortisol, which is released more often with depression, say the doctors. The hormone could reduce the body's DNA repair and immune response, making it harder for the body to fight off cancer. These physical effects could affect the risk of all types of cancer by targeting the body's natural defenses, the doctors warn.
Anxiety and depression increase the risk of heart disease and stroke
The negative effects of psychological problems on the human body have already been proven by previous studies. These showed, for example, that people with neurotic or conscientious personality types are more likely to get sick. Anxiety and depression have already been linked to an increased risk of coronary artery disease and stroke, the researchers add.
More research is needed
Our results help to recognize that poor mental health has some predictive power for certain physical illnesses. However, more research is needed to determine a real causal relationship, the study's authors say. (as)