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Cancer pain management Using evidence to support practice. Mike Bennett Professor of Palliative Medicine Lancaster University . Cancer pain epidemiology. Prevalence. Systematic reviews 48% of patients with early stage cancer 59% undergoing cancer treatment 64-75% with advanced disease
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Cancer pain managementUsing evidence to support practice Mike Bennett Professor of Palliative Medicine Lancaster University
Prevalence Systematic reviews 48% of patients with early stage cancer 59% undergoing cancer treatment 64-75% with advanced disease Hearn and Higginson 2003 Van den Beuken-van Everdingen et al 2007 Surveys (n=5000) 72% of European community patients 77% in UK Breivik et al 2009
Severity Secondary care settings Using 0-10 rating scale (0=no pain, 10=worst) Average pain = 3.7 Maximum pain = 4.8 Two thirds of patients rate greater than 5/10 Klepstad et al 2002, Yates et al 2002 Community settings (n=617 in UK) Average pain = 6.4 90% rated greater than 5/10 25% not receiving any analgesia
Longitudinal data • 116 cancer patients followed-up from 3 months to death • EORTC QLQ C30 monthly intervals • Pain bothered ‘quite a bit’ or ‘very much’ in 57-59% of patients • only 5% experienced improved pain before death Elmqvist et al Supp Care Cancer 2009
Prescribing data • Pain Management Index • analgesic prescription (0-3) MINUS level of pain (0-3) • negative score suggests under treatment • Review of 26 studies • Prevalence of negative PMI in 8 - 82% populations studied • weighted mean = 43% • nearly 1 in 2 patients were ‘undertreated’ Deandrea et al Ann Onc 2008
Proportion of cancer patients in the weeks preceding death who were prescribed analgesics (N=234) Borgsteede et al 2008
Proportion of non-cancer patients in the weeks preceding death who were prescribed analgesics (N=188)
History of the ladder • 1980 – WHO establishes Cancer Control Programme • Cancer prevention • Early diagnosis with curative treatment • Pain relief and palliative care • 1986 – ‘Method for relief of cancer pain’ • 1996 – revised edition published
History of the ladder • Best regarded as a framework of principles and not a rigid protocol • Advocates analgesia: • By the mouth, by the clock, by the ladder • Individualised to patients • Attention to detail • Put oral opioids on the map
WHO ladder in practice • Common mis-interpretations: • starting at step 1 for moderate to severe pain • assuming that the ladder is restricted to opioids • rotating around analgesics at steps 1 or 2 despite inadequate pain relief
WHO ladder in practice • Analgesics are the cornerstone of good cancer pain management • in contrast to management of non-cancer chronic pain • But reducing barriers to pain management also important • educating patients and carers • access to medicines • ………more on these aspects another time!
Effectiveness of the ladder as a whole ....but first some questions about your practice
Do you: • use step 2 before step 3? • and do you think step 1 added to step 3 makes a difference? • initiate strong opioids using immediate release opioids before converting to sustained release? • use morphine as first line strong opioid or do you believe that other opioids are better? • believe that a high proportion of patients need to be ‘switched’?
Effectiveness of the ladder as a wholeEarly evidence • Many observational studies 1985-90 • Reported proportion of patients that achieved adequate control • 3220 patients studied • 2361 (73%) achieved control • One study documented pain scores • 1229 patients; mean reduction in pain intensity >65% Ventafridda et al 1987 • Around 25% of patients do not get adequate pain control
Effectiveness of the ladder as a wholeLater studies • Prospective 10 year study • 2118 patients with cancer pain • data at days 0, 6, 37, 66 (mean intervals) • opioids given • orally (83%) • parenterally (9%) • spinally (2%) • range of co-analgesics too Zech et al 1995 Pain
Effectiveness of the ladder as a wholeLater studies • Pain relief • Good 76% • Satisfactory 12% • Inadequate 12% • No differences in pain intensity or relief between types • but those with NeuP received significantly more co-analgesics Zech et al 1995 Pain Grond et al 1999 Pain
Effectiveness of the ladder as a wholeSystematic reviews • 1995 • 8 studies (1982-1995) • Meta-analysis not possible • ‘adequate pain management in 69-100%’ Jadad and Browman 1995 JAMA • 2006 • 17 studies (8 overlap with earlier review) • ‘adequate pain management in 45-100%’ Ferriera et al 2006 Supp Care Cancer
Evidence base for specific aspectsEAPC guidance • European Association for Palliative Care • Guidance on using strong opioids 1996 • updated 2001 • 20 recommendations
Evidence base for specific aspects‘By the mouth’ • Cochrane review of oral morphine • Clinical trial evidence small Wiffen 2007 • Oral versus transdermal studies • randomised, but non-blind • similar analgesia but less adverse effects with transdermal route • ?drug or delivery system van Serventer et al 2003 Curr Med Res Opin
Evidence base for specific aspects‘By the clock’ • Normal release opioids first? • Randomised, parallel study NR vs SR opioids in 40 patients previously on weak opioids • Both groups achieved adequate pain relief • 2.1. days NR vs 1.7 days SR • SR group reported less tiredness Klepstad et al 2003 Pain • Cochrane review • Supports titration using modified release preparations Wiffen and McQuay 2007, Cochrane Database
Evidence base for specific aspects‘By the clock’ • Regular dosing? • Randomised, crossover studies of ‘as needed’ opioid injections vs subcutaneous infusion • 2 studies (n=22, n=12) over 6 days • 48 hours on each system then crossed over • Total opioid doses similar • Pain scores similar and preferences equal Bruera et al 1988 J Natl Cancer Inst Watanabe et al 2008
Evidence base for specific aspects‘Single or double dose at night?’ • EAPC guidelines suggest double dose of oral immediate release morphine at night • Study 1 • Open, randomised cross-over, n=20 (Davies et al 2002) • DD group; higher pain scores, more breakthrough doses, worse opioid side-effects (vivid dreams, dry mouth) • Study 2 • Blinded randomised cross-over, n=19 (Dale et al 2009) • clinical equivalence between groups
Evidence base for specific aspects ‘By the ladder’ • 2-step or 3-step ladder best?
Evidence base for specific aspects ‘By the ladder’ • Evidence for advantage in moving from step 1 to step 2? • 2 large reviews of NSAIDs +/- weak opioid • Lack of evidence to support significant improvement in pain between these steps Eisenberg et al 1994 JCO McNicol et al 2004 JCO • Additional reduction in pain when adding paracetamol to strong opioid • 0.4 – 0.6 on 0-10 rating scale Stockler et al 2004, JCO
Evidence base for specific aspects ‘By the ladder’ • Step 1 to step 3 safe? • 2 randomised non-blind trials in opioid naïve patients • allocated to strong opioids straight away or step-wise (WHO ladder) approach • strong opioid ‘straight away’ group • better pain relief • more nausea, anorexia and constipation • Design problems • open • baseline pain scores differed in one trial (WHO group worse) Marinangeli et al 2004 J Pain Symptom Manage Maltoni et al 2005 Supp Care Cancer
Morphine or oxycodone first? • RCT cross-over design • 32 patients received Mor or Oxy, then switch after 1 week • 23 completed • Pain scores, side effects and preferences similar Bruera et al 1998, JCO
…..another RCT in 45 patients • 27 completed • Pain control similar • More vomiting with morphine (but nausea same) • More constipation with oxycodone • No other differences in adverse effects Heiskanen and Kalso 1997, Pain
Meta-analyses • Oxycodone in head to head trials • No differences in pain or adverse effects overall against morphine or hydromorphone Reid et al 2006, Ann Oncol
Methadone • Very cheap, more available in developing countries • Double blind RCT methadone vs morphine, n=103 • Both groups 20% reduction in pain • More dropouts in methadone group • Methadone not superior to morphine Bruera et al 2004 JCO
Evidence base for specific aspects‘Individualised to patients’ • Prospective observational study • 186 patients commenced on morphine • 47 (25%) did not respond and needed to switch • 37/47 did well on oxycodone • 10 needed additional switches Riley et al 2006, Supp Care Cancer
Evidence base for specific aspects‘Individualised to patients’ • Systematic review of ‘switching’ • 31 observational studies, small numbers • 12% required a switch • Most patients appeared to benefit • 60-70% patients experienced benefit • median morphine dose fell from 577 to 336mg Mercadante and Bruera 2006 Cancer Treat Rev
WHO analgesic ladder: is it effective in cancer pain? • WHO ladder directly observed in 5000 patients • 75% achieve good control • compare that with amitriptyline or gabapentin in neuropathic pain • current evidence supports flexibility when using WHO ladder • some recommendations may need revising • the broad approach does not
WHO analgesic ladder: is it effective in cancer pain? • Framework of principles • most important contribution as an educational tool • probably qualifies as MRC ‘complex intervention’ • challenging to define and measure effectiveness • Poor implementation accounts for under-treatment of cancer pain
Thank you • m.i.bennett@lancaster.ac.uk