Article (not new) is bad news for stress models of disease

[Woolie]

I just read this article (from 2004). Its pretty good. Edit: Both authors have spent their lives studying the link between stress and disease, so may be biased in favour of positive findings. Keep this in mind as you read.

Psychological stress and the human immune system: a meta-analytic study of 30 years of inquiry.

Its a metanalysis. Tries to gather all studies that have looked at the same thing and calculate average effects across all like studies. Over the short term (e.g. things like exam stress, public speaking), stress enhances several aspects of immune function, especially the natural immune response (NK cells and stuff). But for stress over the long term, results were pretty patchy.

First, the positive outcomes:

* Death of a spouse was the only single event that elicited any significant consistent change in immune response, it was associated with a decline in natural immune response (e.g., reduced NK cell function).

* Chronic stressors, which included dementia caregiving, living with a handicap, and unemployment, also resulted in changes to a number of markers of immunity, including cytokine production, NK cells, and antibodies to herpes viruses.

Now the negative:

* Stressful event sequences, taken together (e.g. death of a spouse, experiencing a natural disaster, possible cancer diagnosis), didn't elicit any consistent pattern of immune change across studies.

* Distant stressors (things like childhood trauma and war experiences many years back) had no consistent reliable effect on immune parameters.

* There is no relationship between people's self-rated stress levels and any immune parameters

The authors suggest that some of the effects of chronic stressors may actually be indirect, and due to things like loss of sleep, changes in smoking habits, etc.

 

[A.B.]

There is no relationship between people's self-rated stress levels and any immune parameters

Bad news for models involving thoughts causing immune changes.

 

[TrixieStix]

I would think this would play right into the issue of epigenetic changes that are brought on by stress/stressors that end up resulting in issues in subsequent generations. Perhaps the biggest risks are not to the person experiencing the stress/or but to their offspring and grandchildren? Will be fascinating to see what science uncovers in the future.

http://theconversation.com/epigenetics-can-stress-really-change-your-genes-55898

 

[Snow Leopard]

Are there any similar systematic reviews published in the last few years?

 

[Effi]

Are there any similar systematic reviews published in the last few years?

This was published last month: What Is the Molecular Signature of Mind–Body Interventions? A Systematic Review of Gene Expression Changes Induced by Meditation and Related Practices

I haven't read it all, but the list of 'methodological problems' is longer than the review itself...

-A major shortcoming of the literature is the lack of active control groups that carefully mirror the MBIs (e.g., length of time, meaningfulness of the practice).

-One other problem to consider are the various environmental and lifestyle factors that may change gene expression in similar ways to MBIs.

-Another limitation is inherent to gene expression data. By themselves these do not provide much useful information unless the relationship between gene expression and psychological variables is directly explored.

-The studies presented considerable variation, both in their type of interventions and gene expression assessment.

-Another source of heterogeneity in the reviewed studies is the cell type from which gene expression data are collected.

-Another aspect to bear in mind is that the biological consequences of the observed gene expression changes were not found directly, because the studies that employed circulating proteins (e.g., CRP, interleukins, or cortisol) generally did not find significant results.

-One final methodological concern has to do with the assessment of inflammation. (...) if a single inflammatory measure has decreased after an intervention, we cannot confidently conclude that the immune system is enhanced.

Although the studies reviewed here provide preliminary evidence that MBIs are associated with a reduced risk of inflammation-related diseases, it is unclear whether they are more effective than a range of lifestyle changes commonly recommended as a part of healthy lifestyle, such as regular exercise and a Mediterranean diet.

Yet the newspaper headlines for all these reviewed studies probably read something along the lines of: "Mindfulness helps you heal your [insert any inflammation related illness]!"

 

[anciendaze]

You might compare this with results reported in this TED talk by an imaging researcher and psychiatrist who has done many thousands of SPECT scans. Notice how he describes psychiatric practice without a scan as "throwing darts in the dark." There is definite evidence that psychiatric diagnoses are not particularly useful in discovering etiology or useful interventions. Completely different organic conditions can yield the same diagnosis.

Likewise, from a number of studies of inherited major psychiatric disorders we know that even patients who inherit a gene which guarantees they will have some such disabling disorder can have one of four different diagnoses: depression, bipolar disorder, schizophrenia, schizoaffective disorder. This covers the majority of the landscape of clinical psychiatry. In case you were wondering, there have also been studies of hundreds of carefully-diagnosed schizophrenics, none of whom had this genetic marker. What does this tell you about the research utility of psychiatric diagnoses, beyond determining that "something is wrong"?

How long will some psychiatrists continue to "throw darts in the dark" without learning anything? It depends on how long the patient survives.

BTW: did I mention that DISC1 directly affects mitochondrial function? It could cause some forms of exercise intolerance not normally considered psychiatric. Considering the utter failure of current practice in the field to either reduce prevalence or even identify the problem, I consider the idea of throwing more patients into this medical oubliette perverse.

Added: I must apologize to Woolie for hijacking this topic. This was simply on my mind when I caught up on my reading of this forum, and this failure of the concept of psychological stress to yield useful interventions pushed me over the edge. There is a personal aspect: my father went through a great deal of advice about dealing with "stress" when he had peptic ulcers. This was at a time when doctors were pooh-poohing the idea that antibiotics might cure ulcers quickly despite the fact that appropriate antibiotics were already available.

I'm afraid what we have here is a subject that tells you far more about effects caused by false beliefs of doctors than those of patients. Why do educated people believe such things when there is little or no objective basis?

And the beat goes on...recent news includes the important advice that mental activity, control of blood pressure and exercise can stave off dementia. I note that control of blood pressure is entirely aimed at hypertension, which is definitely bad, but ignores the possibility that episodes of hypotension and cerebral ischemia could be a factor. Patients with dysautonomia are once again left out.

Nowhere in the articles about this do I see adequate controls to distinguish the possibility that those who did better simply had less severe or less progressive organic illness. You might as well tell people research shows it is best to be lucky.

 

[Woolie]

Are there any similar systematic reviews published in the last few years?

Not that I could find, @Snow Leopard. One problem in this area is that researchers who do these reviews have generally dedicated their careers to finding linkages between psychological stress and health. So there's no such thing as an objective review.

Even the review above, which is one of the better ones, did seem to be a little confused about correlation and causation in parts. For example, they examined whether the "stress" of an HIV diagnosis might "cause" immune changes. I'm not kidding, they really did this! (they mentioned as an afterthought that other factors might be driving the immune changes here, but that didn't seem to be reason enough to exclude the analysis!).

I also think its very concerning that even situations we'd all agree are chronically challenging, like death of a spouse or caring for a dementing loved one, are associated with very different types of immune profiles. To me, it suggests other major factors are at play. So caring for a dementing spouse imposes a lot of practical demands on the person, and I dare say sleep interruption would be huge amongst those.

You really need to see if stress adds in anything that's can't be explained by more direct factors like changes to sleep patterns.

 

[Woolie]

Added: I must apologize to Woolie for hijacking this topic. This was simply on my mind when I caught up on my reading of this forum, and this failure of the concept of psychological stress to yield useful interventions pushed me over the edge. There is a personal aspect: my father went through a great deal of advice about dealing with "stress" when he had peptic ulcers. This was at a time when doctors were pooh-poohing the idea that antibiotics might cure ulcers quickly despite the fact that appropriate antibiotics were already available.

Yea, I totally sympathise. I don't think researchers in these areas realise that if they get it wrong, real people will suffer. They think they are being helpful but they're not.

And the benefits of this research seem low to me too. There's no real avenue for prevention. Its not like we willingly walk into the kinds of stressful situations that were in that review. We know these things are unpleasant already. People are thrust into these situations by circumstances and through their sense to duty to each another. So what use is it to see the health evidence except just to make us feel worse about our situation? People won't think, "Oh, now I know the science, I'm getting out - I'm dumping grannie at the hospital!".

Some say, well, it might help to know the health consequences so we can offer more support? Really? Isn't it plain people in these situations need support? What idiot needs to see health data to work out that a man who has just lost his wife of 50 years is going to be having a tough time and will need help?

And there's something circular about it all. There's no objective definition of stress or even stressful situations, so its a judgement call from the very start. Researchers often define "stressful events/situations" as things most of us imagine would be really hard to handle. Then they aim to show that these things are indeed really hard for people to handle, as indexed by various health measures. But we knew that already - isn't that how we decided what would count as "stressful" in the first place? It just goes round in a big circle.

 

[Woolie]

This was published last month: What Is the Molecular Signature of Mind–Body Interventions? A Systematic Review of Gene Expression Changes Induced by Meditation and Related Practices

Man, one the one hand you've got these folks looking at "bad" stuff and trying to show that its indeed bad. Then here, you've got a thing we currently think is "good", and people trying to throw a lot of science at it to show its good. A few decades ago, it might have been hatha yoga or EST, now its meditation and mindfulness. The question is just so overlaid with human values and current popular beliefs, it kind of goes nowhere.

If meditation makes you feel good, then its worth doing, right? Isn't that all we need to know?

 

[Effi]

If you meditation makes you feel good, then its worth doing, right? Isn't that all we need to know?

If I want to sell more classes and make a ton of money, then no.

 

[anciendaze]

Anyone feel like following up on the idea that research shows it is best to be "lucky"? I could imagine a research publication created by taking an existing paper and simply substituting words.

In the travesty that passes for Congressional debate over healthcare reform here in the U.S. we just had a politician suggest that people with pre-existing conditions were like those who must pay higher rates for automobile insurance because they have had more accidents.