1. Preventing Pain From Becoming
Chronic With Early Intervention
Dr Yeo Sow Nam
Director, The Pain Specialist,
Mount Elizabeth Hospital &
Founder and Past Director,
Pain Management and Acupuncture Services,
Singapore General Hospital
MBBS (Singapore)
MMED (Anesthesiology, S’pore)
FANZCA (Anesthesiology, Aust/NZ)
FFPMANZCA (Pain Medicine, Aust/NZ)
FAMS, Registered Acupuncturist
2. What Is Chronic Pain?
• Defined as pain persisting over 3 months
• Subdivided into chronic malignant pain
and chronic non-malignant pain
• Probably not directly related to initial
injury or disease but is secondary to
physiological changes in pain signalling
and detection
• Often associated with the emergence of a
complex set of physical and psychological
changes that are an integral part of the
chronic pain problem
• Poses particular therapeutic challenges
1. Merskey H, Bogduk N., Classification of Chronic Pain, 1994, IASP Press. ISBN-13: 978-0-931092-05-3
2. Woolf CJ, Mannion RJ. Neuropathic pain: aetiology, symptoms, mechanisms, and management. Lancet. 1999;353:1959-64.
(Page 1959)
3. Ashburn MA, Staats PS. Management of chronic pain. Lancet. 1999;353:1865-9. (Page 1865 / 1866)
4. Portenoy RK, Kanner RM. Pain Management: Theory and Practice. Philadelphia PA: FA Davis & Co; 1996. (Page 7, Table 1-2)
3. Chronic Pain: A Disease In Its Own Right
The World Health Organization
(WHO) notes that “chronic pain
should be accepted as condition in
its own right and highlights the
great burden of chronic pain on
individuals”.
World Health Organization. WHO Normative Guidelines on Pain Management. June 2007. Available at
http://www.who.int/medicines/areas/quality_safety/delphi_study_pain_guidelines.pdf (Page 17) Accessed June 25th 2012.
5. Burden Of Chronic Pain
Carries great economic costs – Direct and Indirect
Financial cost of chronic pain is roughly the same as Cancer or CV diseases.
The costs include –
• Healthcare and medication expenses
• Absenteeism from work, impaired
performance and work disruptions
• Income loss
• Loss of productivity in sufferer’s home
• Financial burden on family, friends and
employers
• Social and compensation costs
Unrelieved pain: Major Global Healthcare Problem. IASP & EFIC document. Available at http://www.iasp
pain.org/AM/Template.cfm?Section=Home&Template=/CM/ContentDisplay.cfm&ContentID=2908 accessed June 28th 2012
6. Burden of Chronic Pain
Impact on daily life
Breivik H et al. Survey of chronic pain in Europe: prevalence, impact on daily life, and treatment. al. EurJ JPain.2006;10:287-333
Breivik H et
Eur Pain 2006;10:287-
333. (Page 295/309)
7. Chronic Postsurgical Pain Is A Common But Under-
recognized Problem
Estimated incidence Estimated incidence of Estimated US surgical
of chronic severe (disabling) pain volumes (1000s)
postsurgical pain
Inguinal hernia repair 10% 2–4% 600
Lower limb amputation 30–50% 5–10% 160
Breast surgery 20–30% 5–10% 480
(lumpectomy or
mastectomy)
Thoracotomy 30–40% 10% 200
Total knee arthroplasty 12% 2–4% 550
Coronary artery bypass 30–50% 5–10% 598
surgery
Caesarean section 10% 4% 220
7
1. Kehlet H, et al. Lancet 2006;367:1618-1625;
2. Durkin B, et al. Expert Opin Pharmacother 2010;11:2751-2758.
8. 8
Sub-optimal Pain Management
Can Have Economic Consequences
Re-admissions following day-care surgery
Other
17%
Surgical • Mean charges for patients
21% re-admitted
due to pain were
ADE
3%
$1,869±4,553 per visit*
Medical • Of patients re-admitted for
14% pain, 38% had undergone
orthopaedic procedures
Bleeding
Pain 4%
38% N/V
3%
*Mean inpatient re-admissions for pain $13,902±11,732 per visit
ADE, adverse drug event
N/V, nausea/vomiting
Coley KC, et al. J Clin Anesth 2002;14:349-353.
9. Risk Factors For Development Of Persistent
Postsurgical Pain
1. Genetic susceptibility
2. Moderate to severe preoperative
pain
3. Psychosocial factors
4. Age and sex
5. Surgical approach with risk of
nerve damage
6. Poorly controlled postoperative
pain
1. Kehlet H, et al. Lancet 2006;367:1618-1625;
2. Durkin B, et al. Expert Opin Pharmacother 2010;11:2751-2758;
3. Schug SA, Pogatzki-Kahn EM. Pain: Clinical Updates 2011;19:1-5. 9
10. Transition Of Acute To Chronic Pain
– Psychological Variables
• Acute pain intensity and depressive
symptoms each positively and directly
influence the persistence of neck and back
pain and disability and are also positively
intercorrelated
• Research suggests exposure to severe
stressors can permanently change
neurobiological processes or structures,
negatively affecting arousal thresholds
and ability to cope with subsequent stress
Casey Y et al. Transition from acute to chronic pain and disability: A model including cognitive, affective, and trauma
factors. Pain 2008;134:69–79
11. Hypothesized Model Of Transition From Acute To
Chronic Pain And Disability
Casey Y et al. Transition from acute to chronic pain and disability: A model including cognitive, affective, and trauma
factors. Pain 2008;134:69–79
12. Predictive Factors Of Pain Transition
• Greater exposure to past traumatic life events
and depressed mood is most predictive of
chronic pain
• Depressed mood and negative pain beliefs is
most predictive of chronic disability
• More cumulative traumatic life events, higher
levels of depression in the early stages of a new
pain episode, and early beliefs that pain may be
permanent significantly contribute to increased
severity of subsequent pain and disability
Casey Y et al. Transition from acute to chronic pain and disability: A model including cognitive, affective, and trauma factors.
Pain 2008;134:69–79
13. Reducing Pain Related Fears Could Reduce Chronicity
• Highest correlations were found
among the pain-related fear
measures and measures of self-
reported disability and behavioural
performance
• Questionnaires to quantify pain-
related fears, include –
– Fear-Avoidance Beliefs
Questionnaire (FABQ)
– Tampa Scale for Kinesiophobia
(TSK)
– Pain Anxiety Symptoms Scale
(PASS)
Crombez G et al. Pain-related fear is more disabling than pain itself: evidence on the role of pain-related fear in chronic back
pain disability. Pain. Mar 1999; 80(1-2):329-39.
14. Reducing Pain Related Fears Could Reduce Chronicity
• Controlling for socio-demographics,
multiple regression analyses revealed
that the subscales of the FABQ and the
TSK were superior in predicting self-
reported disability and poor behavioral
performance
• PASS appeared more strongly associated
with pain catastrophizing and negative
affect, and was less predictive of pain
disability and behavioral performance
Crombez G et al. Pain-related fear is more disabling than pain itself: evidence on the role of pain-related fear in chronic back
pain disability. Pain. Mar 1999; 80(1-2):329-39.
15. Early Intervention For Pain
• Inefficient or ineffective
treatment of acute pain can lead
to chronic pain states
• Chronic pain is associated with
morphological changes in the CNS
Early intervention can benefit patients at high risk of
developing chronic pain
Gatchel RJ et al. Treatment- and cost-effectiveness of early intervention for acute low-back pain patients: a one-year
prospective study. J Occup Rehabil. Mar 2003;13(1):1-9.
16. Results Of Early Intervention
• Gatchel et al., reported the effect of early intervention
on 124 patients with acute low-back pain
• High-risk patients randomly assigned to –
– Early intervention group (n = 22),
– Non intervention group (n = 48)
• Low-risk subjects (n = 54) who did not receive any early
intervention was also evaluated
• All these subjects were prospectively tracked at 3-month
intervals starting from the date of their initial evaluation,
culminating in a 12-month follow-up
Gatchel RJ et al. Treatment- and cost-effectiveness of early intervention for acute low-back pain patients: a one-year
prospective study. J Occup Rehabil. Mar 2003;13(1):1-9.
17. Results Of Early Intervention
• The early intervention program involved an
interdisciplinary team approach consisting of
four major components—
• Psychology
• Physical therapy
• Occupational therapy
• Case management
Gatchel RJ et al. Treatment- and cost-effectiveness of early intervention for acute low-back pain patients: a one-year
prospective study. J Occup Rehabil. Mar 2003;13(1):1-9.
18. Results Of Early Intervention
Gatchel RJ et al. Treatment- and cost-effectiveness of early intervention for acute low-back pain patients: a one-year
prospective study. J Occup Rehabil. Mar 2003;13(1):1-9.
19. Results Of Early Intervention
Gatchel RJ et al. Treatment- and cost-effectiveness of early intervention for acute low-back pain patients: a one-year
prospective study. J Occup Rehabil. Mar 2003;13(1):1-9.
20. Results Of Early Intervention
• High-risk subjects who received early intervention displayed
statistically significant fewer indices of chronic pain
disability on a wide range of work, healthcare utilization,
medication use, and self-report pain variables, relative to
the high risk subjects who do not receive such early
intervention
• In addition, the high-risk non intervention group displayed
significantly more symptoms of chronic pain disability on
these variables relative to the initially low risk subjects
• There were greater cost savings associated with the early
intervention group versus the no early intervention group
Gatchel RJ et al. Treatment- and cost-effectiveness of early intervention for acute low-back pain patients: a one-year
prospective study. J Occup Rehabil. Mar 2003;13(1):1-9.
21. Summary
• Pain can broadly be classified as acute & chronic
• Chronic pain is often associated with the emergence of a complex set of physical and
psychological changes that are an integral part of the chronic pain problem
• Chronic pain poses special therapeutic challenges
• Chronic pain carries direct and indirect economic costs and has great impact on daily life
• Although most episodes of acute pain resolve within 6 weeks, nearly half of the pain sufferers
have symptoms which persist and debilitate them for years
• Inefficient or ineffective treatment of acute pain can lead to chronic pain states
• Subjects at risk of acute pain turning chronic who receive early intervention show fewer indices
of chronic pain disability and include more work efficiency, less healthcare utilization, medication
use and self-reported pain
• There are greater cost savings associated with early intervention
Hinweis der Redaktion
Nociceptive pain*Pain that arises from actual or threatened damage to non-neural tissue and is due to the activation of nociceptors.Note: This term is designed to contrast with neuropathic pain. The term is used to describe pain occurring with a normally functioning somatosensory nervous system to contrast with the abnormal function seen in neuropathic pain.Neuropathic pain*Pain caused by a lesion or disease of the somatosensory nervous system.Visceral pain is caused by inflammation of serous surfaces, distention of viscera and inflammation or compression of peripheral nerves. It is diffuse and often referred to somatic sitesRef: Merskey H, Bogduk N., Classification of Chronic Pain, 1994, IASP Press ISBN-13: 978-0-931092-05-3 Cervero F, Laird JMA. Visceral pain. Lancet 1999; 353:2145–2148.
The World Health Organization (WHO) notes that chronic pain should be accepted as condition in its own right and highlights the great burden of chronic pain on individuals
Key points: Genetic susceptibility – A number of single nucleotide polymorphisms (SNPs) have been identified to closely correlate with persistent postsurgical pain. For example, specific haplotypes of catechol-O-methyltransferase (COMT) are correlated with an increased risk of developing chronic temporomandibular joint pain. Moderate to severe preoperative pain – Preoperative pain is consistently found to be a predictor for persistent postsurgical pain, which might reflect an independent risk factor, but which may also be a manifestation of predisposing factors. Psychosocial factors – Expectation of pain, fear, past memories, social environment, work, and levels of physical activity, all affect the response to noxious stimuli. Age and sex – In post-herniorrhaphy pain, older patients have a reduced risk of developing chronic pain; in contrast, it has been shown that there is a reduced incidence of post-thoracotomy pain syndrome in children and adolescents. Findings of several studies show that women have higher postoperative pain than men. Surgical approach with risk of nerve damage – Operations with a high risk of nerve injury carry a high risk of persistent postsurgical pain. This will be discussed in the following slides. Poorly controlled postoperative pain – Severity of acute postoperative pain is closely correlated with development of persistent postsurgical pain. This will be discussed in a later slide.References:Kehlet H, et al. Lancet 2006;367:1618-1625.Durkin B, et al. Expert Opin Pharmacother 2010;11:2751-2758.Schug SA, Pogatzki-Kahn EM. Pain: Clinical Updates 2011;19:1-5.
Acute pain intensity and depressive symptoms each positively and directly influence the persistence of neck and back pain and disability and are also positively intercorrelatedResearch suggests exposure to severe stressors can permanently change neurobiological processes or structures, negatively affecting arousal thresholds and ability to cope with subsequent stress
Greater exposure to past traumatic life events and depressed mood is most predictive of chronic painDepressed mood and negative pain beliefs is most predictive of chronic disabilityMore cumulative traumatic life events, higher levels of depression in the early stages of a new pain episode, and early beliefs that pain may be permanent significantly contribute to increased severity of subsequent pain and disability
Questionnaires to quantify pain-related fears, include –Fear-Avoidance Beliefs Questionnaire (FABQ)Tampa Scale for Kinesiophobia (TSK)Pain Anxiety Symptoms Scale (PASS)Highest correlations were found among the pain-related fear measures and measures of self-reported disability and behavioral performance
Controlling for sociodemographics, multiple regression analyses revealed that the subscales of the FABQ and the TSK were superior in predicting self-reported disability and poor behavioral performancePASS appeared more strongly associated with pain catastrophizing and negative affect, and was less predictive of pain disability and behavioral performance
Poorly managed acute pain can lead to chronic pain statesIf pain is not treated adequately at an early stage, it often becomes more difficult to treatChronic pain, a history of pain-associated surgeries and low social support are negative predictors for treatment outcomeOver time, chronic pain leads to morphological changes in the central nervous systemReferences:1 Schulte E, Hermann K, Berghöfer A, et al. Referral practices in patients suffering from non-malignant chronic pain. Eur J Pain. 2010;14:308.e1-308. (Page 308, e1)2 Tracey I, Bushnell MC. How neuroimaging studies have challenged us to rethink: is chronic pain a disease? J Pain. 2009;10:1113-20. (Page 1117)3 Apkarian AV, Sosa Y, Sonty S, et al. Chronic back pain is associated with decreased prefrontal and thalamic gray matter density. J Neurosci. 2004;24:10410-5 (Page 10410)
In an attempt to prevent acute low back pain from becoming a chronic disability problem, an earlier study developed a statistical algorithm which accurately identified those acute low back pain patients who were at high risk for developing such chronicity. The major goal of the present study was to evaluate the clinical effectiveness of employing an early intervention program with these high-risk patients in order to prevent the development of chronic disability at a one-year follow-up. Approximately 700 acute low back pain patients were screened for their high-risk versus low-risk status. On the basis of this screening, high-risk patients were then randomly assigned to one of two groups: a functional restoration early intervention group (n=22), or a non-intervention group (n=48). A group of low-risk subjects (n=54) who did not receive any early intervention was also evaluated. All these subjects were prospectively tracked at 3-month intervals starting from the date of their initial evaluation, culminating in a 12-month follow-up. During these follow-up evaluations, pain disability and socioeconomic outcomes (such as return-to-work and healthcare utilization) were assessed.
The early intervention program involved an interdisciplinary team approach consisting of four major components—PsychologyPhysical therapyOccupational therapyCase management
Results clearly indicated that the high-risk subjects who received early intervention displayed statistically significant fewer indices of chronic pain disability on a wide range of work, healthcare utilization, medication use, and self-report pain variables, relative to the high-risk subjects who do not receive such early intervention.
In addition, the high-risk non-intervention group displayed significantly more symptoms of chronic pain disability on these variables relative to the initially low risk subjects. Cost-comparison savings data were also evaluated. These data revealed that there were greater cost savings associated with the early intervention group versus the no early intervention group. The overall results of this study clearly demonstrate the treatment- and cost-effectiveness of an early intervention program for acute low back pain patients.
High-risk subjects who received early intervention displayed statistically significant fewer indices of chronic pain disability on a wide range of work, healthcare utilization, medication use, and self-report pain variables, relative to the highrisk subjects who do not receive such early intervention.In addition, the high-risk nonintervention group displayed significantly more symptoms of chronic pain disability on these variables relative to the initially low risk subjectsThere were greater cost savings associated with the early intervention group versus the no early intervention group
