Does “Success” of Psychological Treatments of Chronic Pain Need to be Taken With a Grain of Salt?

One of the problems defining chronic pain as a psychological condition, is the fact that psychological treatments have somewhat mediocre results. So when I find an article claiming results, I am suspicious. Here is an example:

Int J Behav Med. 2009 Dec 2. [Epub ahead of print]
Two Psychological Interventions Are Effective in Severely Disabled, Chronic Back
Pain Patients: A Randomised Controlled Trial.
Glombiewski JA, Hartwich-Tersek J, Rief W. abstract here

OK – how can one fudge results?

1) Take a severely disabled groups – “recruited from a highly disabled group” – depression is going to be a significant factor by then and any procedure that gives hope will have an impact, and exercise is a known anti-depressant. – so results might be more related to depression treatment rather than any direct anti-pain effects
2) Pick a control group with no placebo effect – The control group was a wait list – jesse – you not going to see any hope effects there….

3) Ignore drop outs – 11 cases dropped out so only were using the highly motivated subjects

However:

• The pain intensity went down from 5.9 to 4.5 = 1.4 drop; wait list went down from 6.3 to 5.7.- a drop of 0.6
• From multiple fibromyalgia studies, I have seen the placebo “hope” effect drop pain by 1/7 = 0.9/6.3. If you add any natural attrition of pain (was 0.6 in the wait group) to that you would have a drop of pain by 1- 1.5 no longer any difference between groups.
• Another issue is the fact some authors consider a drop of 2 is needed to be Clinically Significant so a drop of 1.4 – does not cut it….??

Comment:

Proponents of the psychological basic of chronic pain are dogged by they fact working the psychological aspects of chronic pain does not necessarily result in any “cures”. This study is no cure either..

To people who pretend chronic pain is psychological I have one question/statement:

“Show me the money!!!” – if it’s psychological, lets see mass cures with psychological treatments- this is not happening…

as Apkarian (2009)articulated:

Prog Neurobiol. 2009 Feb;87(2):81-97
Towards a theory of chronic pain.
Apkarian AV, Baliki MN, Geha PY.

abstract here

“Accepted In general, a long series of studies now describe psychosocial and psychological factors in predicting functional and social disability, where the interrelationship between ratings of catastrophizing, pain-related fear of (re-) injury, depression, disability, and pain severity are studied and modeled in combination with demographics in various chronic pain conditions. Yet while these factors may be associated with pain in certain individuals, attempts to create models of chronic back pain based upon them have been unproductive.

For example, one model – the fear-avoidance model (Vlaeyen and Linton,
2000) – suggests that fear of pain and related pain behaviors can be relieved by exposing
individuals to movements and tasks they have avoided due to fear of (re-) injury,
predicting that such exposure should then result in reducing the intensity of chronic pain.
To test this, a recent randomized controlled trial investigation (Woods and Asmundson,
2007) assessed effectiveness of exposure relative to other conditions in 45 chronic low
back pain patients. Although the exposed patients improved on a long list of measures
related to fear, the primary outcome measure regarding their disability showed no
improvement. Further, if psychological and social factors had strong power in predicting
chronic back pain, then quality of life and health care utilization, which have been shown
to be dependent upon such factors (Keeley et al., 2007) should also show a relationship
with a developing a chronic pain condition. Yet even when back pain is caused by a
major physical trauma (Harris et al., 2007a), they remain only weakly related to chronic
pain. It is now being recognized that psychosocial factors constitute “non-negligible
risks” for the development of low back pain (Clays et al., 2007), and cannot account for
how or why a patient transitions into the chronic pain state. A recent article titled “Why is
a treatment aimed at psychosocial factors not effective in patients with (sub) acute low
back pain?” (Jellema et al., 2005) concisely articulates the need to direct studies of
chronic pain elsewhere.”

Dr. Harold Mersky, father of the pain definition, and expert of the psychiatric aspects of chronic pain, has articulated, there is a big difference from finding statistical significance of psychological factors in chronic pain, and that difference being clinically relevant and useful.

There is also the fact that Apkarian (mentioned above) has found people with chronic pain can develop atrophy of the dorsolateral prefrontal cortex (DLPFC), which will induce depression – so that chronic pain patients can come by the depression quite “honestly”.

Addendum – having said that, antidepressants have been shown to stimulate brain cell growth and ameliorate that effect.
Any comments here?