Pain and Somatisation
A Lecture given at the Royal College of Physicians, February 1st 2007
Dr Ben Green, Consultant Psychiatrist, Cheadle Royal Hospital and Honorary Senior Lecturer, University of Liverpool.
In classical textbooks of psychopathology pain is usually classified as a mood state, not as a perception, (i.e. this is because pain is not considered one of the traditional five senses). As we will see pain has much to do with anxiety and depression, but it is difficult to see very localised pain, say to the foot alone, as a mood state and some revision of the conventional concept of ‘five senses’ is probably overdue.
Pain involves a sensation that causes suffering and much depends on the ‘meaning’ of the pain to the patient for instance is a pain in the throat interpreted by the patient as a sore throat or as incipient throat cancer? The interpretation of the sensation is affected by the patient’s mood state, expectation, temperament, experience and education. And again some inherently painful acts, even such as laceration of the skin, can be altered by the cognitive set of the person. Self-laceration in people who deliberately repeat cutting behaviour is usually described as it being painless, or even a ‘relief’ from tension. The sensation of pain can therefore be seen to be cognitively modulated by higher brain centres.
Pain is frequently not associated with a firm organic diagnosis (e.g.atypical facial pain) and is sometimes associated with psychiatric diagnoses such as anxiety disorder and depression. Hypochondriasis is a of course a morbid preoccupation with the body or state of health associated with concern about minor pains and other bodily symptoms. Hypochondriacal disorder is an example of a ‘somatoform disorder’.
Psychiatrists are often asked to comment in medicolegal cases whether pain is physical or mental in origin. This may follow, say, an orthopaedic report which talks about the patient’s pain in terms which may involve ‘exaggeration’, ‘inappropriate signs’, ‘supratentorial’ or ‘functional’ pain. The courts may even ask psychiatrists and psychologists to determine a percentage of how much of the pain is psychogenic or even whether the patient is malingering. This area of medicolegal practice is very difficult as the psychiatrist is currently reliant on the subjective experience reported by the patient.
Some psychiatrists e.g. Trethowan (1988) and Tyrer (1986) have attempted to list certain differences between psychiatric and organic pain:
- Psychiatric pain is more diffuse and less localised and does not follow an anatomical distribution.
- Pain persists unremittingly in psychogenic cases, whereas physical pain may ebb and flow and be worsened or relieved by specific measures.
- Psychogenic pain may follow on from a previous mood disorder.
- Psychogenic pain is difficult to for the patient to describe qualitatively. Organic pain sufferers will use terms like ‘burning’ for skin, ‘shooting’ for nerve pain and so on.
- Psychogenic pain may develop and worsen without evidence of increased tissue damage.
In two thirds of Tyrer’s 1985 series of patients with pain with no organic cause he found there was major depressive disorder. The remaining third had personality disorders, anxiety states, hysteria and drug dependence.
Setting aside for a moment how true organic pain is reflected in presentations to psychiatry how is abnormal pain behaviour classified in ICD-10?
According to ICD-10 there are several somatoform disorders, for instance:
- F45.0 Somatization disorder
- F45.2 Hypochondriacal disorder
- F45.3 Somatoform autonomic dysfunction
- F45.4 Persistent Somatoform pain disorder
F45.0 Somatization disorder is not simply a disorder where there is somatisation of emotional distress. The definition requires quiet a severe range of symptoms present over two years. The must be multiple and variable physical symptoms for which there is no physical explanation, a refusal to accept reassurance and impairment of social and family functioning associated with the symptoms. DSM IV is even more pedantic requiring four pain symptoms, two gastrointestinal symptoms, one sexual symptom and one pseudoneurological symptom at least. It’s very rare – accounting for only 0.2% of a liaison psychiatry consultation service’s referrals Smith et al, 2000). The diagnosis originates from Briquet's syndrome.
F45.2 Hypochondriacal disorder requires a persistent belief in the presence of serious physical illness despite repeated investigations to the contrary and a refusal to accept reassurance. Hypochondriacal ideas should not be delusionally held however.
F45.3 Somatoform autonomic dysfunction involves troubling symptoms such as palpitations, sweating, tremor, flushing that the patient is preoccupied with and cannot be reassured about despite the exclusion of more serious disease. There is a sense of some overlap with hypochondriacal disorder.
F45.4 Persistent Somatoform pain disorder is where there is persistent and predominant complaint of severe and distressing pain which is not explained by a physical cause. It often occurs in association with emotional conflict or psychosocial problems. It results in extra support and attention. The diagnosis presumes that no other psychiatric disorder is present.
Criticisms of the somatoform classification include the lack of acceptability to patients who find the labels stigmatising and infer that doctors believe that the distress they have is purely in their mind. this can lead to disengagement from services and anger. The co-operative model of cognitive behavioural therapy seeks to assure the patient that their distress is seen as genuine although other explanations need to be considered.
The somatoform group is also somewhat artificial and separate from aetiology .there may also be the dangers associated with old-fashioned hysterical and conversion disorder diagnosis, namely that unusual physical diagnoses e.g. SLE or neurosyphilis are missed.The cautionary and landmark study by Eliot Slater springs to mind. In 1965 Eliot Slater published a paper in the BMJ which reported a ten year follow up of patients at the National Hospital for Nervous Disease (Slater & Glithero). These erstwhile neurological patients had been diagnosed with 'hysteria'. At follow-up a half had developed conditions that could explain their earlier presentations - either serious psychiatric conditions or complicated neurological conditions.
The probability that somatoform diagnoses are incorrect rises with the age of the patient and the sophistication of their health beliefs and knowledge.
Over the thirty or so years since Slater's paper the risk of an incorrect or missed diagnosis for 'unexplained motor symptoms' appears to have diminished. This could be due to a more sophisticated health knowledge in patients or a more sophisticated diagnostic approach by doctors. A 1998 study where there was a six year follow up of 64 patients at the same hospital found that only 10% had 'new' conditions that could explain their previous symptoms - half of these were serious psychiatric conditions and half organic conditions.
Of course there are some who feign illness and portray themselves as in pain for primary gains such as analgesia e.g. pethidine or monetary gain - benefits, court claims etc. Factitious disorder is an example of this kind of condition. Sometimes this is termed Munchausen's syndrome, or hospital hopper syndrome. An associated condition pseudologica fantastica is sometimes described. Personality disorders are often co-morbid. Treatment is difficult as any confrontation usually leads to flight and a lack of engagement with any psychological therapy that is offered.
True organic pain can present to psychiatry as well. Chronic pain, even low-level pain is associated with the phenomenon of secondary depression. Although this depression could resolve on the pain being relieved and although the depression is therefore seen as an ‘understandable’ consequence of pain it is not logical to withhold any treatment for the depression as treatment (despite the continuation of chronic pain) will usually alleviate some of the depression and may also improve the ‘perception’ of the pain. A bi-directional relationship thus often exists between the pain and the depression.
A recent study of 100 consecutive pain clinic attenders found 59% had depression and generalised anxiety in 55% (Rivera et al 2005). There is obviously a high degree of co morbidity of pain and psychiatric disorders.
Recent epidemiological research (Demyttenaere et al, 2006) in a sample of over 21,000 Europeans found that painful physical symptoms were reported by 29% of those in the sample without depression, but in 50% of those with major depression. The patients with pain and depression were less likely to seek help and delay seeking help.
Chronic pain has been estimated to affect about a fifth of Europeans extrapolating from the results of a study of 46,000 subjects (Breivik et al , 2006). Most had visited their GP, but only 2% had been treated by a pain specialist. (rates are similar for depression – prevalence up to 20% and only about 2% of them have seen a consultant psychiatrist)
Psychiatric Strategies Contributing to Pain Management
- All health professionals should be trained to screen/interview pain clinic patients for suicidal ideation and intentions. This will reduce completed suicides.
- Vigorous treatment of co morbid anxiety and depression
- Cognitive Behavioural Therapy e.g. challenging automatic thoughts, reduction in pain catastrophizing (Smeets et al 2006)
- Treating depression with antidepressants - (Feinmann (1984) found an impressive resolution of atypical facial pain within 9 weeks in 71% of patients treated with dosulepin (dothiepin). Mirtazapine may be helpful in allaying sleep difficulties and treating depression. Tricyclics may have their own separate analgesic effect. However prescribers should be wary of potential problems with contraindications in pain patients. The use of low doses in pain management may offset some of the main difficulties however. Gore et al analysed the records of 13,456 pain patients in UK general practice and found that nearly 50 % had been prescribed to people where there was cautions or contraindications. The average dose was only about 30 mg however.
- Mood stabilisers- lamotrigine, carbamazapine, valproate(Ettinger & Argoff, 2007)
- Anxiolytics: pregabalin (150-600mg daily) has been found to be superior to gabapentin in managing diabetic neuropathic pain and postherpetic pain in 126 canadian patients (Tarride et al, 2006)
- Hypnosis - 19th Century exponents from Manchester's James Braid to the twentieth century US psychiatrist Milton Erickson have all described the ameliorating effects of hypnosis. Jones' 2006 Manchester study found that hypnotherapy helped in non-cardiac chest pain in 80% of patients receiving it compared to 23% of control patients who received placebo medication and supportive therapy.
- Alteration of coping strategies. (Depression and passive coping style leads to particularly slow recovery after whiplash – Caroll et al 2006)
- [ECT – some studies have found improvements in non-depressed pain sufferers Usui, 2006 and also rTMS Sampson, 2006]
Malcolm is a 45 year old insurance salesman with great anxiety about his sales targets. He also has diabetes mellitus. He has developed some neuropathic pain in his legs and has formed the idea that his legs will need to be amputated in the next six months. he is also frightened because his brother died of a heart attack when he was aged 45. he has been having panic attacks at work and has been signed off by his GP with depression.
A conventional aetiological matrix can be drawn up that helps us consider aspects of the case that can be tackled, bit-by-bit to improve his mental health and sense of well being.
|Biological||Neuropathic pain||Childhood Illness||Somatic Symptoms of Anxiety|
|Psychological||Fear of Death and associated anxiety||Brother's early death||Need for reassurance|
Waiting List for Pain Clinic
He has probably after all had the common experience meted out to diabetics that 'if you don't do x you will lose y (or go blind, have a stroke, have a heart attack)'. Patients hear such injunctions frequently from nurses and doctors. The explanation from such professionals is that they intend to motivate the patients. Such injunctions may compel compliance, but they have hidden costs to the patient. Of course these professionals would agree that not all patients with diabetes go blind, lose their legs to gangrene or have stroke. However the patient hears such injunctions in just such a way and the assumption that their health is certain to be horribly complicated by blindness is born. It's like reverse cognitive behavioural therapy!
The diagram below shows how there is a self re-inforcing cyce fuelling anxiety, automatic thoughts and reassurance seeking behaviours. CBT would seek to challenge his automatic thoughts about losing his job and the inevitability he accords the thoughts about imminent death. Problem solving skills would be recruited to help him generate new outcomes and strategies to divert his attention from his internal somatic sensations to the external world. Some elements of bereavement therapy could be incorporated.
There is absolutely no reason why CBT cannot be accompanied by pharmacological strategies to tackle anxiety, depression and pain. A holistic and pragmatic management strategy is after all most likely to be successful.
In challenging pain attention MUST be given to the aspects of anxiety and depression that usually accompany it. A better outcome is certain. Given the widespread nature of chronic pain these aims should be given a higher public health priority and the relative lack of pain management consultants and psychiatrists with an interest in pain is a national disgrace.
Breivik H. Collett B. Ventafridda V. Cohen R. Gallacher D. Survey of chronic pain in Europe: prevalence, impact on daily life, and treatment. European Journal of Pain: Ejp. 10(4):287-333, 2006
Carroll, L J. Cassidy, J D. Cote, P./ The role of pain coping strategies in prognosis after whiplash injury: passive coping predicts slowed recovery. Pain. 124(1-2):18-26, 2006
Crimlisk, H L et al. Slater revisited: 6 year follow up study of patients with medically unexplained motor symptoms.BMJ, 318: 582-586.
Demyttenaere, K. Bonnewyn, A. Bruffaerts, Ry. Brugha, T. De Graaf, R. Alonso, J. Comorbid painful physical symptoms and depression: prevalence, work loss, and help seeking .Journal of Affective Disorders. 92(2-3):185-93, 2006 Jun
Ettinger A & Argoff C. Use of antiepileptic drugs for nonepileptic conditions: psychiatric disorders and chronic pain. Neurotherapeutics, 4(1):75-83, 2007.
Gore et al. Prevalence of contraindicated medical conditions and use of precluded medications in patients with painful neuropathic disorders prescribed amitriptyline. Pain Practice 6(4) 265-72, 2006.
Jones, H, Cooper, P, Miller, V, Brooks, N. Whorwell, PJ. Treatment of non-cardiac chest pain: a controlled trial of hypnotherapy. Gut, 55: 1403-1408, 2006.
Rivera et al. Reliability of psychological evaluation in chronic pain in an interventional pain management setting. Pain physician, 8(4): 375-83, 2005.
Sampson SM. Rome JD. Rummans TA. Slow-frequency rTMS reduces fibromyalgia pain. [Clinical Trial. Journal Article] Pain Medicine. 7(2):115-8, 2006
Slater, E. Diagnosis of Hysteria. 1(5447):1395-9.BMJ, 1965.
Slater, E & Glithero E. Follow up of patients diagnosed as suffering from 'hysteria'. J Psychosom Res,; 9:9-13, 1965.
Smeets, R J E M. Vlaeyen, J W S. Kester, A D M. Knottnerus, J A. Reduction of pain catastrophizing mediates the outcome of both physical and cognitive-behavioral treatment in chronic low back pain. Journal of Pain. 7(4):261-71, 2006 Apr.
Smith GC, Clarke DM Handrinos D et al. Consultation-liaison psychiatrists’ management of somatoform disorders. Psychosomatics, 41, 481-489, 2000.
Tarride et al. Cost effectiveness or pregabalin for the management or neuropathic pain associated with diabetic peripheral neuropathy and postherpetic neuralgia: a Canadian perspective. Clinical therapeutics. 28(11): 1922-453, 2006.
Tyrer S. Learned Pain Behaviour. BMJ, 292, 1-2 ,1986.
Tyrer S. Psychosomatic pain. British Journal of Psychiatry. 188:91-3, 2006
Usui C. Doi N. Nishioka M. Komatsu H. Yamamoto R. Ohkubo T. Ishizuka T. Shibata N. Hatta K. Miyazaki H. Nishioka K. Arai H. Electroconvulsive therapy improves severe pain associated with fibromyalgia. Pain. 121(3):276-80,