Mind over matter

Amanda Sheppeard looks at how science is exploring the link between stress and disease.

JOHN was 37 when he was diagnosed with acute rheumatoid arthritis (RA). It was a major blow for the active father-of-three who had built a successful career as a master jeweller with one of Sydney’s most exclusive jewellery houses.

It was a high-stress job – tight deadlines, demanding customers and long hours. As John’s disease progressed, he started to see a pattern emerging with his symptoms and the level of stress he was under.

“When I became stressed or was under a lot of pressure, I could literally see my joints swelling and I felt terrible,” he recalls.

“There was no doubt in my mind that there was a link.”

While he says there was “a lot of other treatment involved” in managing his RA, effectively dealing with his stress levels played an important role. 

“Understanding how to manage my stress was a signpost out of the darkness, it really was.”

John’s story might only provide anecdotal evidence of a direct link between a person’s stress levels and the health of their immune system, but there is a growing amount of research to support the view that there is a definite link. 

It even has a name – psycho­neuroimmunology (PNI) – and a groundswell of support from professionals across a range of craft groups.

Among them is clinical psychologist with MS Australia Dr Gary Fulcher (PhD), who is also the organisation’s PNI consultant.

“There is good evidence that stress and other psychological factors affect the immune system,” he says. 

“In fact, wellness and illness need to be considered as psychoneuroimmunological states rather than physical states.

“The central nervous system, endocrine system, immune system, enteric nervous system, autonomic nervous system and consciousness work in unison to produce those states of wellness and illness.

“Stress stimulates the hypothalamic-pituitary-adrenal axis and the [autonomic nervous system], which causes the release of hormones, neurotransmitters, and the neuropeptides that drive activity in the immune system and the endocrine system.”

STRESS LINK

Dr Fulcher says there are many animal and human studies that show the disease is more prevalent among those people experiencing stress.

Now researchers at the University of California, Los Angeles, think they may have demonstrated the pathway linking chronic stress and an increased inflammatory response and how it differs in individuals. 

A recent study in the Proceedings of the National Academy of Sciences shows results from two different types of stress tests: public speaking and social rejection.1 The psychologists found that individuals who exhibited greater neural activity in the dorsal anterior cingulate cortex and anterior insula during social rejection in the brain scanner also exhibited greater increases in inflammatory activity when exposed to acute social stress in the lab.

OLD NEWS

Victorian GP and deputy head of Monash University’s department of general practice, Dr Craig Hassed, is another proponent of PNI, but is quick to point out it is not a new concept. 

He says the term was first coined in the 1970s by the University of Rochester’s Dr Robert Ader, who conducted an experiment on rats that documented the first hard clinical evidence of a physiological link between the mind and the body.

“This is not necessarily new, but it’s the kind of thing not being widely taught in medical education and at the practice level,” Dr Hassed says.

“There is a huge amount of evidence on PNI. In fact, there are whole medical journals dedicated to it. This is beyond a theory – there just isn’t any doubt.”

Dr Hassed says there are many parameters to this concept, especially as stress is highly personal. 

Sometimes it can be subtle. Physical responses to stress can be as simple as a sore throat or as serious as auto-immune conditions, cardiac problems and even cancer. 

The severity of the response can also depend on genetic factors, like predisposition to certain conditions, such as diabetes or other auto-immune diseases.

Dr Fulcher says there is a very clear process a person experiences when they are placed under stress that contributes to poorer MS outcomes.

“There are 17 studies in MS that have shown a very clear association between stressful events and MS activity, attacks and relapses,” he explains.

He accepts the argument that everyone is exposed to stress, so it is not the stress that causes the illness; he presents an interesting analogy to this argument.

“Everyone is exposed to viruses every day; some people get sick, some don’t – it is the same with stress,” he says.

What is important, he adds, is the way people deal with that stress.

“There are strong individual differences in how people manage stress,” he explains.

“People who use active coping skills have less illness response under stress than those with passive or avoidant coping skills. This is good news, because people can learn better ways to deal with stress that are health protective.”

Dr Katharine Hodgkinson (PhD), a Sydney-based clinical psychologist and director of Headway Health, who works primarily with cancer patients, says that while stress can sometimes be used as a motivator for patients battling the disease, there is little doubt it can have a degenerative effect on their ability to manage.

“There is a large overlap between symptoms of stress, anxiety, depression, fatigue, nausea and pain – there is little doubt that it can exacerbate the symptoms they already have,” says Dr Hodgkinson, who co-edited Psychosocial Care of Cancer Patients, a book to assist health professionals.

Some signs to look out for are disturbed sleep patterns, a decreased appetite, or an increase in ‘self-medication’, such as an increased use of caffeine, alcohol or smoking. 

According to US researchers looking at cancer and stress, these types of “poor health behaviours may potentiate the effects of stress, and their co-occurrence for the cancer patient may add psychological and biological burdens”.2 

On the other hand, directing patients to exercise or stress-relief activities such as yoga may have a positive effect on the immune system and, in turn, “important health consequences” in disease progression from Epstein-Barr to cardiovascular conditions to cancer. 

For Dr Hodgkinson, communication with patients about their stress levels is crucial to attaining better outcomes. 

Further reading and websites

MS Australia – ACT/NSW/VIC: aims to promote networking and understanding of PNI and MS, www.pnims.org The journal, Brain, Behaviour, and Immunity, 

http://www.elsevier.com/wps/find/journaldescription.cws_home/622800/description#descriptionThe Essence of Health, by Dr Craig Hassed

The American Psychological Association has a number of articles on the issue, including www.apa.org/monitor/dec01/anewtake.aspx

Trends in Immunology 2005; 26:644-52 The role of stress response systems for the pathogenesis and progression of MS. This article can be accessed at www.sciencedirect.com.

References: 

1. Published online before print August 2, 2010, doi: 10.1073/pnas.1009164107

2. Am Psychol 1994; 49(5):389-404