Case study : opioids in chronic pain

Background (age, sex, occupation, baseline function)

• 74-year-old female
• Lives in ground floor flat
• Mobilises with walking aid but currently housebound 

History of presentation/reason for review

• Identified for review by a search in her GP practice (using Scottish Therapeutics Utility (STU)), as she is prescribed a high dose opioid (>50mg morphine equivalent)
• Currently taking Longtec® 90mg daily plus Shortec® 30mg daily (i.e. 180mg morphine equivalent daily (MED) dose)

Current medical history and relevant co-morbidities

• Lower back pain episode - six years ago
• Transient diplopia - cause uncertain – 10 years ago
• Essential hypertension – 14 years ago
• Barrett’s oesophagus with hiatus hernia – 14 years ago
• Chronic lower back pain - 24 years ago
• Cerebrovascular disease – 25 years ago
• Seronegative polyarthropathy – 25 years ago
• Osteoporosis – 26 years ago
• Anxiety – 31 years ago

Current medication and drug allergies (include over the counter (OTC) preparation, traditional medicines and herbal remedies)

Allergies or adverse drug reactions (ADRs)

• Adverse reaction to aspirin previously - GI upset

Current medication

• Amlodipine 5mg tablets: one tablet daily
• Clopidogrel 75mg tablets: one tablet daily
• Diazepam 2mg tablets: one tablet daily in the morning
• Longtec® 40mg tablets: one tablet twice daily
• Longtec® 5mg tablets: one tablet twice daily
• Mirtazapine 15mg tablets: one tablet at night
• Nitrofurantoin 50mg capsules: one capsule at night
• Omeprazole 20mg capsules: one capsule twice daily
• Oxybutynin 2.5mg tablets: one tablet twice daily
• Paracetamol 500mg tablets: two tablets three times daily
• Quinine sulphate 200mg tablets: one tablet at night
• Ramipril 10mg capsules: one capsule daily
• Senna 7.5mg tablets: two tablets at night
• Shortec® 10mg capsules: one capsule six hourly, as required
• Vitamin D3 1000IU capsules: one capsule daily
• Zopiclone 3.75mg tablets: one tablet at night

Over the counter medicines: nil

Lifestyle and current function

• Clinical Frailty Score (Rockwood) 6 (moderately frail)
• Medication in compliance aid
• No difficulty swallowing medicines
• Carers four times a day for personal care/medication prompt/meals/shopping
• Appears a bit confused at times but lucid and normally perceptive (MMSE score 26/30 on testing three months ago)
• Smokes 15 cigarettes a day
• Reports no alcohol or recreational/over the counter drug use
• Reports poor appetite and diet but weight stable at 32kg:
  • Three years ago 38kg
  • Two years ago 34.1kg, with dietetic input started
  • Now on sip feeds and carers add in full cream milk, biscuits etc

“What matters to me” (ideas, concerns and expectations of treatment)

• Very fixed mindset on requirement for all medicines. Denies any side effects
• Would like to reduce pain levels - widespread pain in back, joints, and stomach. She rates her pain as 10/10
• Would like to go to bingo but has lost confidence to leave the flat
• Keeps herself happy by feeding birds/foxes - misses her dog who died last year

Observations, examinations and results 

Note: local laboratory reference ranges may vary

• Weight 32kg (stable for last six months), Height 140cm, BMI 16.3kg/m²
• Urea and electrolytes– within range three months ago, eGFR greater than 60ml/min/1.73m², calculated creatinine clearance 33mL/min
• BP average over three readings 145/85mmHg, no postural drop
• Serum cholesterol 4.4mmol/l (<5.0mmol/L), HDL/LDL ratio 3.8 (for women <2.5)
• DXA six years ago after being on bisphosphonate for five years. T= -2.7 Advised to stop bisphosphonate for two years and then re DXA - GP to refer again

Most recent relevant consultations

• Pain and polypharmacy review during a home visit three months ago. Brief Pain Inventory score average is 9/10 (unable to score interference questions, analgesic effectiveness 0-10%) 
• GAD score 9/21
• Weekly phone calls to practice over last six months for a variety of complaints: urinary tract infection (UTI), upper respiratory tract infection (URTI), stomach pains

Follow-up:

• Regular contact with community link worker and follow-up with pharmacist to implement pain and polypharmacy medication review changes. Medication changes discussed, but reluctant to try some of them. Signposted to the resources “My Live Well with Pain” website
• Follow up every four to six weeks to review medication changes - slow, gradual changes with regular reassessment and individual choice over which medications to deprescribe and when

Person specific issues to address

• Does not want to stop any medication, reports all are effective despite pain 10/10. “If it’s not broke, don’t fix it”
• Wants to go out to bingo/shops
• Challenge of matching her expectations of remaining on all medicines versus reducing risks of ADR/side effects. Suspicious of reviews due to past experiences.
• Discuss realistic expectations of pain management
• Discuss non-pharmacological ways of managing pain
• Develop a therapeutic relationship

 

Person specific issues to address

• Essential – none

 

Person specific issues to address

• Nitrofurantoin: complains of UTI despite continuous nitrofurantoin. CrCl 33ml/min, so should be avoided and no evidence to support prophylactic use beyond six months. Trial without
• Mirtazapine, zopiclone and diazepam: contributing to anticholinergic burden (ACB). Review and rationalise if possible after opioid reduction. Reassess GAD. Not keen to engage with mental health teams currently, has tried before, with no benefit
• Zopiclone: trial reduction after opioids have been reduced 
• Amlodipine: BP adequately controlled, with no postural drop 

 

Person specific issues to address

• Bone protection: awaiting DXA, receives vitamin D but no calcium, however her diet is calcium rich with full fat milk, cream and cheese
• Previous cerebrovascular disease – no statin prescribed. Discuss if this has been stopped previously, reasons for discontinuation and if appropriate to restart?

 

Person specific issues to address

• Quinine sulfate: still reports leg cramps, therefore trial without  
• Oxybutynin: high ACB. She reports previous catheterisation because of urinary retention. Trial discontinuation to reduce ACB, then assess urinary frequency
• Opioids: she reports 10/10 for pain despite 180mg MED dose.Discuss ADR and potential harm, increasing risk of falls, hyperalgesia, impact on cognition, sedation, immune suppression, query a factor in recurrent UTIs
• Plan: reduce oxycodone by 7-10% every two to four weeks to achieve lowest possible dose
• Paracetamol: Reduce dose to one tablet as weight less than 50kg
• Omeprazole may reduce efficacy of clopidogrel – change to lansoprazole
• Reassess BP after medicines are deprescribed with potential to reduce ramipril

Medication Sick Day Guidance given for ramipril

 

Person specific issues to address

• Check local formulary choices for sustained-release oxycodone and if necessary, switch to a more cost-effective preparation when a stable dose is reached 
• Advised to dispose of medicines through the community pharmacy 
• Advised to only order what is needed, do not stockpile medicines  

 

Agreed plan

• Unwilling to change pain medicines at first but willing to ‘trial’ reduction of therapy at subsequent consultations  
• Gradual changes in medicines discussed and agreed
• Stop: nitrofurantoin, oxybutynin, quinine sulfate
• Reduce: opioids, then zopiclone
• Reduce: paracetamol dose
• Change: omeprazole to lansoprazole
• Option to include functional assessment scores before and after medication changes, along with the pain score 
• Refer to community link worker for social prescribing and community support options
• Attitude to smoking explored and reports reducing her cigarette smoking to less than eight a day

After four months follow-up, she had reduced to 45mg oxycodone (67.5mg MED). Pain still 9/10, but now going out with carer one day a week and visiting shops