Sunday, 19 July 2015

A case of mind over matter: pain in multiple sclerosis

Eur J Neurol. 2015 Jul 14. doi: 10.1111/ene.12763. [Epub ahead of print]

Beyond a physical symptom: the importance of psychosocial factors in multiple sclerosis pain.

Harrison AM, Silber E, McCracken LM, Moss-Morris R.

Abstract
BACKGROUND AND PURPOSE:Pain affects around two-thirds of people with Multiple Sclerosis (pwMS). Biomedical treatments show limited efficacy. A recently developed cognitive-behavioural model of Multiple Sclerosis (MS) pain suggests several psychosocial factors may worsen pain and related disability. The current study investigated whether psychosocial factors drawn from this model explain significant amounts of the variance in pain severity and interference over and above measures of disease severity and pain subtype.

METHODS:Six hundred and twelve pwMS experiencing pain completed a UK wide cross-sectional survey including valid and reliable psychometric questionnaires. Hierarchical regressions determined the relative contribution of disease severity and psychosocial factors to predicting pain severity and interference.

RESULTS:All psychosocial factors including distress, negative beliefs about pain and its consequences, and avoidance of activity, were related to pain outcomes, explaining a further 24% and 30% of the variance in pain severity and interference after controlling for demographic and disease variables. Findings were similar for neuropathic and non-neuropathic pain subgroups.

CONCLUSIONS:All pwMS reported significant pain and associated disability even though over 90% were taking pain medication. Psychosocial factors identified as important in predicting pain severity and, to a greater extent, pain interference are potentially modifiable and may be important treatment targets for both pain subtypes.

It is estimated that around two-thirds of MSers experience pain, of which 5-32% when questioned perceive as severe. Pain in this particular study is reported as the fourth most common interfering symptom in MS, after fatigue, sexual dysfunction and balance difficulties. I have discovered as opposed to musculoskeletal (muscular, joint pains etc), neuropathic pain (due to a primary lesion or disease of the central nervous system) is particularly debilitating and exceptionally difficult to treat. In this study 50% of those questioned achieved pain relief with the prescribed pain medication (acetaminophen - paracetamol in the UK, anticonvulants, NSAIDs, tricyclic antidepressants, opioids, cannabinoids, compound analgesics, serotonin-norepinephrine reuptake inhibitors).

It has been long appreciated that whilst the MS disease process triggers the pain, a range of personal factors also determine the severity, extent and resulting disability of the pain. These factors include perception, emotional and behavioural responses to the pain, as well as the level of social support. The authors point out that many focus on the pain control or trying to reduce it, often worsening rather than lessening the pain.

In this study, for neuropathic pain, disease variables (MS subtype, current relapse, EDSS etc.) accounted for 16% of the pain severity, whilst the personal factors accounted for a further 20% (even controlling for emotional factors such anxiety and depression in the analysis has overall little effect on the figures).

The authors also found that certain factors were more pronounced in their contribution to perceived pain severity and level of pain interference with life - individuals with "higher levels pain severity and pain interference may have a greater tendency to magnify or exaggerate the threat or seriousness of pain sensations (catastrophic thought processes) and are more affected or influenced by the of their own thoughts (cognitive fusion). Greater pain is also associated with a tendency to avoid physical and social activities when in pain, with greater anxiety and depression, and with viewing pain as persistent over time and having serious consequences. It is also worth noting that persisting with activity (endurance) either showed small negative correlations with pain f no relationship, suggesting that maintaining activity does not worsen pain whilst avoidance does".

Below is a cognitive (thinking) behavioural model of and treatment for chronic pain published in the article:

Figure: Interacting biopsychosocial factors felt to contribute to pain severity and pain interference in MS. Bold text are factors that may play an important role in MS, grey text have weaker evidence with findings consistent in only a few studies, and italicized text may play an important role in primary chronic pain but not investigated in MS. * Pain acceptance has a significant behavioural component and is therefore represented in both cognitive and behavioural sections of the model.

Overall, I feel a significant amount of the perceived severity and pain interference is modifiable through programmes such as mindfulness, which is a holistic mind-body based approach that allows a person to manage their thoughts an feelings. It is more than simply sitting on a psychologists couch and talking, but is run by trained occupational and physiotherapists, and psychologists with an in-depth knowledge of the neurological condition involved. Getting access to them is, however, is the hard bit.

9 comments:

  1. Hmm, perhaps or perhaps not! For over 6-months I worked with a clinical psychologist and OT on mindfulness and other pain management strategies. It hasn't worked for the TN one bit, possibly helped the other sensory pain but not to any large extent. As I was reluctant to take medication as I'm wary of side affects, I really wanted this to work. The OT and psychologist both, in the end, said try the drugs. Not that there 100 per cent affective either. I do find the whole NHS push of mindfulness a little suspect as there is a risk of setting up individuals to feel like failures if it doesn't work for them. Apart from that risk, I do feel it's worth ago for a lot of things so I'm not coming from an 'anti' stance.

    I do feel though, that mindfulness is in the "hip" phase of any 'new' thing and everything (cost also plays apart on this) will be thrown at it. Eventually, this will settle down and more discernment will be used in what it really works for, sort of works for or has no effect whatsoever.

    ReplyDelete
  2. I don't understand the point of this study. I find it condescending and sad. If the point to the study is to understand psychosocial factors that contribute perception of pain, then it does not need to be a study with the word "MS" in front of it to make it relevant. Pain management is a difficult and convoluted area of medicine. It seems more could be gained from trying to understand existing research on the subject (even if it comes from other areas of medicine) then using surveys and hierarchical regressions to pretend to try to understand what the MS patients are reporting. This just reminds me of reading stories from MS patients diagnosed 15 years ago who would describe hard wrenching stories of professionals not believing the pain they were reporting.
    Bojana

    ReplyDelete
    Replies
    1. Yes, I was told 20 years ago that you don't have pain with MS. Well, that sounded similar to the locum GP that told me I couldn't walk because I was neurotic. I get sick of this kind of research.

      Delete
    2. Sometimes I suspect some studies have a lot to do with keeping researchers employed and a little bit less to do with improving the outlook of people with MS, but then again I'm a cynic. There is no objective way to measure levels of pain in individuals nor to understand why some people have lower pain thresholds than others. I think the idea that a survey using hierarchical regressions can objectively quantify the level of pain in percentages is bordering on ridiculous (disease variables apparently accounted for 16% of pain severity while personal factors accounted for 20% of pain severity). Pain management is an important and relevant topic for people with MS. I don’t feel like this study adds anything that wasn’t known already outside the MS world. Doing a study to confirm what’s already known does indeed apply to people with MS seems a pointless waste designed more to give the researcher a job then truly help people with MS.

      This simple government health page on pain management discusses every single point this study has raised as a chronic pain management tool - http://www.betterhealth.vic.gov.au/bhcv2/bhcarticles.nsf/pages/Pain_management_adults?open

      So why do we need to waste time money and energy doing studies to find out what we already know?

      Bojana

      Delete
  3. As I said in my post at 11.03am (writing on my iPhone so limited in how much I could write), I tried this for 6 months and while I wouldn't say it had no affect on the less serious sensory pain, it did zero for TN. I'm concerned that researchers believe it can work for all types of pain in MS and the implication that 'catastrophising' and negative identity plays a part. Perhaps in some cases but not all. I'm quite a self-actualised person, rarely see anything in black and white and flexible in my approach to trying things (within limits), and I can state with certainty that no way did mindfulness help with TN pain (taking a hammer to smash my face might have more affect). Similarly optic neuritis.

    So I don't believe it is a good idea to claim that managing your 'thoughts and feelings,' through CBT is going to help with this. As for acceptance, to some degree, yes this can help in some types of pain, to some degree, but perhaps the researchers might like to experience the worst possible toothache magnified one hundred times and see how easy it is to understand neurological pain and accept it. More than anything it concerns me that 'mindfulness' is being seen as the potential 'cure all' for all MS pain, so if it doesn't work then you were not doing it right, you have negative ideas about self blah blah blah etc etc.

    I guess in my case it did work, in a perverse way, in that the OT and clinical psychologist realised its limits and urged me to try the medication, as they saw I really gave it a good shot and I have accepted that I need to try the medication and put up with the crappy side affects.

    ReplyDelete
  4. I have postive things to say about CBT and mindfulness for my MS. Good to hear there is research in this area. I don't think mindfulness is being seen as a cure all for MS pain.
    I know when I get stressed and anxious I feel more pain. I limit the medication pain killers I take as I don't know how these are affecting me long term. I walk around often in pain but when I lay down I feel well again, no pain, like before MS first reared it's ugly head.

    ReplyDelete
  5. I have been reading through all your comments and would like to add a few points:
    1) TN - I assume trigeminal neuralgia does fall under the neuropathic pain umbrella. However, it has well recognised and effective therapies from carbamazepine, acute phenytoin, ending at radio frequency ablation. Mindfulness and other forms of CBT are unlikely to achieve anything further and above what these can achieve.
    2) Generalised neuropathic pain, however, is trickier to manage and this is where additional therapies such as mindfulness may have a role to play. I suspect that these centralised pain management programmes are probabling altering pain threshold levels or releasing endogenous opioids/cannabinoids.
    3) All pain medications alter your bodies pain gating mechanism at a physiological level. There is acclimatisation to dose over time and sometimes withdrawing them out may be the solution for resetting the status quo. Amitriptylline and gabapentin have good long term safety profiles, I'm uncertain of the synthetic opioids.
    On balance until better therapeutic options come along I say don't close your mind off to alternative therapies that may provide an additional crutch - I thought I'll never live to see the day when I'll say this! But the longer I practice medicine the more I realise that my colleagues in other therapy arms may have a point.

    ReplyDelete
    Replies
    1. I very much agree. I didn't want to take medication for the TN (I'm particularly wary of potential cognitive affects), hence trying various mindfulness and other strategies (including acupuncture and reflexology) but they really did not help. I don't tend to conjure up catastrophising narratives anyway but even if I did, TN pain doesn't give you that 'luxury';). But I can see mindfulness could work with some types of pain and I don't consider it 'mumbo jumbo'. But it is more a concern (probably unwarranted as there are so few clinical psychologists anyway who are trained in this viz.MS) that it may set up some individuals to feel they have failed if the therapy doesn't help. Expectations can be very corrosive, sometimes.

      Delete
    2. Agree - it's difficult to get programmes with expertise in neurological disorders as pain management is mostly focused on musculoskeletal pain. Hopefully this will improve as the referrals increase.

      Delete

Please note that all comments are moderated and any personal or marketing-related submissions will not be shown.