Approaches to Managing Neuropathic Pain. Nov 7, 2017

Transcription

1 1 Approaches to Managing Neuropathic Pain Nov 7, 2017

2 3 Learning objectives Review the current Canadian Guidelines on Neuropathic Pain Review the diagnosis and options available for the management of Neuropathic Pain DPN: diabetic peripheral neuropathy

3 Case Vignette: Paul, 55 years old 4

4 5 Patient profile Paul is a head dispatcher for a large trucking firm He has been married for 22 years and has 3 children He is overweight but is watching his diet He has a family history of cardiovascular disease He was diagnosed with diabetes 12 years ago He is not physically active, walking required for his work causes pain on the soles of his feet He quit smoking 6 months ago. * e.g., PharmaCheck, MedsCheck, etc.

5 6 Reason for visit Paul has not been sleeping well, feeling very tired lately He is concerned that his medications or his blood sugar levels need to be reviewed He asks if you can help identify what may be causing his tiredness Along with discomfort and pain from pressure of feet on ground while walking, he experiences a burning sensation in his legs at night, and he often kicks off his bedding

6 Reason for visit, continued 7 He believes the tiredness and pain in his legs is affecting his mood Because his father had arthritis he wondered if this was a possibility He has tried ibuprofen and acetaminophen but these rarely alleviate the pain At home, he has been resting more and doing fewer activities; he is frustrated because these measures have not helped His weight has begun to drift up because he is less active now than a year ago

7 Medical conditions As documented in file 8 Diabetes Kidney function Obesity Recently Quit Smoker Hypertension Dyslipidemia Erectile dysfunction generally well controlled, periods of suboptimal control normal addressed primarily through diet, minimal exercise quit 6 months ago with the aid of medication and counselling well controlled on medications at target on medication started on medication last year

8 9 Current medications Atorvastatin 20 mg once daily in the evening Gliclazide 160 mg BID Metformin 1000 mg BID with or after meals Hydrochlorothiazide 25 mg once daily in the morning Ramipril 10 mg once daily ASA 81 mg daily when he remembers Sildenafil 100 mg as needed ASA: acetylsalicylic acid BID: twice daily

9 10 Question Based on Paul s history and presentation do do you think he has Diabetic Peripheral Neuropathy (DPN)?

10 11 What is DPN? The presence of symptoms and/or signs of peripheral nerve dysfunction in people with diabetes after the exclusion of other causes Diabetic neuropathies* can be categorized as focal or diffuse, of the latter, DPN is the most common DPN initially involves damage to small nerve fibers; large fibers are affected as the condition progresses Small nerve fibers -> sensitivity to sharpness, pain and heat Large nerve fibers -> touch and pressure sensation *Appendix: A American Diabetes Association. Diabetes Care 2011; 34 [suppl1]:s11-s61; Boulton AJ et al. Diabet Med 1998;15:508-14; Boulton AJ et al. Diabetes Care 2005;28:956-62; Hartemann A et al. Diabetes Metab 2011;37:377-88; Rutkove SB. JAMA 2009;302:

11 12 Signs and symptoms of DPN Tingling (paraesthesiae) Pain Burning Shooting ( electric shock ) down the legs Lancinating ( stabbing or knife-like ) Allodynia (contact pain, often with clothes or bed covers) Walking barefoot on marbles or walking on hot sand Sensations of heat or cold in the feet Persistent ache in the feet or cramp-like sensations in the legs Stocking-glove distribution Argoff CE et al. Mayo Clin Proc. 2006;81(14)(suppl):S12-S25; Boulton AJ et al. Diabetes Care 2004;27: ; Boulton AJ et al. Diabetes Care 2005;28: ; Lautenbacher S et al. Sleep Medicine Reviews (2006) 10, ; Tesfaye S. Br J Vasc Dis 2003; 3:

12 13 Signs and symptoms of DPN Up to 50% of patients with DPN are asymptomatic Diagnosis may be made on clinical examination or when patient presents indicating he/she has a sore that is not healing, suggesting a painless foot ulcer Symptoms are usually worst at night, disrupting sleep Boulton AJ et al. Diabetes Care 2005;28:956-62; Hartemann A et al. Diabetes Metab 2011 (Aug 3); doi: /j.diabet ; Lautenbacher S et al. Sleep Medicine Reviews 2006; 10:357-69; McCracken LM, Iverson GL. Pain Res Manage 2002;7(2):75-9; Rutkove SB. JAMA 2009;302:

13 14 Risk factors for DPN Hypertension Triglycerides Smoking Duration of Diabetes DPN Uncontrolled Blood Glucose Obesity Impaired Glucose Tolerance Boulton AJ et al. Diabetes Care 2005;28: ; Canadian Diabetes Association. Can J Diabetes 2008;32(suppl 1): S140-S142; Hartemann A et al. Diabetes Metab 2011;37:377-88; Tesfaye S et al. N EngJ Med 2005;352: ; Ziegler D. Diabetes Care 2008;31 (Suppl. 2):S255 S261.

14 15 Prevalence of DPN Develops in 28% to 55% of patients with diabetes Painful DPN: 15-20% of patients with type 2 diabetes approximately 5% of those with type 1 diabetes DPN is underdiagnosed, due in part to asymptomatic presentations Boulton AJ et al. Diabetes Care 2005;28: ; Canadian Diabetes Association. Can J Diabetes 2008;32(suppl 1): S140-S142; Hartemann A et al. Diabetes Metab 2011;37:377-88; Herman WH, Kennedy L. Diabetes Care 2005;28:1480-1; Rutkove SB. JAMA 2009;302:1451-8; Ziegler D. Diabetes Care 2008;31 (Suppl 2):S255-S261.

15 16 Consequences of DPN Educating patients with DPN about appropriate foot self-care can minimize complications American College of Foot and Ankle Surgeons. American Diabetes Association. Tesfaye S. Br J Vasc Dis 2003; 3:112-17; Young MJ et al. Diabetes Care 1994;17:557-6.

16 17 1. What factors in Paul s history and presentation suggest he may suffer from DPN? Symmetrical burning pain, allodynia, discomfort and pain from pressure of feet on ground while walking with no current causative injury Risk factors: 12-year history of diabetes, periods of less than optimal blood glucose control, recently quit smoker, obesity, hypertension, dyslipidemia Complaints of lack of restful sleep and tired legs may be consequences of his pain Pain related to arthritis is not likely, no relief with ibuprofen Assessment of pain would help determine whether his pain is neuropathic

17 18 Group discussion question 2. You suspect that Paul s pain is the result of DPN. What do you do first?

18 19 Management considerations Treatment of pain and other signs and symptoms (e.g. sleep disturbance) Glycemic control, including lifestyle modification Foot care DPN Management Boulton AJ et al. Diabetes Care 2005;28:956-62; Lautenbacher S et al. Sleep Medicine Reviews 2006; 10:357-69; Rutkove SB. JAMA 2009;302:

19 Screening/diagnostic considerations 20 Patients should be regularly and systematically questioned about possible symptoms, as these are not usually volunteered Earlier detection may contribute to improved management of glycemic control and prevention of DPN complications Hartemann A et al. Diabetes Metab 2011;37:377-88; Herman WH, Kennedy L. Diabetes Care 2005;28:

20 21 Differential diagnosis DPN is a diagnosis of exclusion, complex investigations to exclude other conditions are rarely needed Disorders that mimic DPN can include: lumbar stenosis, spinal cord disorders, orthopaedic foot problems (e.g. plantar fasciitis), digital neuropathies, restless legs syndrome, peripheral vascular disease The most common diagnostic error is attribution of the pain to arterial disease Discomfort from pain on soles of feet vs. claudication type pain that may be intermittent while walking American Diabetes Association. Diabetes Care 2011;34 (suppl 1): S11-S61; Canadian Diabetes Association. Can J Diabetes 2008;32(suppl 1): S140-S142; Hartemann A et al. Diabetes Metab 2011;37:377-88; Rutkove SB. JAMA 2009;302:

21 22 Practice pearls Screen for signs and symptoms of DPN as part of regular follow-up or medication renewal in patients with diabetes Ask patients when they last checked or had a healthcare professional check their feet Document their response and refer patients to their primary healthcare provider to confirm diagnosis

22 23 2. You suspect that Paul s pain is the result of DPN. What do you do first? First, educate and remind Paul benefits of lifestyle improvement (diet, exercise, and footcare), continued smoking abstinence, to help alleviate symptoms Goals could include some or all of the following: 1. Improve his pain 2. Improve his sleep 3. Reduce his fatigue 4. Improve his mood 5. Maintain his ability to work and feel comfortable

23 24 Group discussion question 4. What treatment would be appropriate? What would you recommend to help Paul sleep better?

24 Non-pharmacologic treatment options 25 Not Recommended Insufficient evidence Magnetic field treatment Low-intensity laser therapy Exercise Acupuncture Reiki therapy Bril V et al. Neurology 2011;76:20:

25 26 Pain and sleep disturbance Patients with chronic pain syndromes often complain of disturbed sleep, insomnia and daytime fatigue DPN can interfere with sleep time and quality Lack of REM sleep may lower the patient s resistance to pain and discomfort and interfere with their cognitive ability and day-to-day decision making REM: rapid eye movement Foral P et al. Consult Pharm 2011;26:414-25; Onen SH et al. Clin J Pain 2005;21:422-31; Qureshi A, Lee-Chiong T. Med Clin N Am 2004;88:

26 Canadian Neuropathic Pain Guideline Recommendations 2014 Gabapentinoids TCA SNRI Tramadol CR Opioid Analgesic Cannabinoids Fourth-line agents (topical lidocaine, methadone, lamotrigine, tapentadol, botulinum toxin) Moulin D, et al. Pain Res Manag 2014;19:328 Consider adding additional agents sequentially if partial but inadequate

27 Evidence-based treatment options Non-pharmacologic and pharmacologic 28 Pregabalin (Level A) and duloxetine (Level B) are indicated for neuropathic pain associated with DPN Other options (Level B): e.g. amitriptyline, venlafaxine, gabapentin, capsaicin cream If cost is a concern, tricyclic antidepressants and generics may be considered Opioids should be used only in patients failing to respond to non-opioid treatment Bril V et al. Neurology 2011;76:20: ; Cymbalta product monograph. Eli Lilly Canada Inc. April 8, 2011; Lyrica product monograph. Pfizer Canada Inc. June 21, 2010; Hartemann A et al. Diabetes Metab 2011;37:377-88; St. Onge EL, Miller SA. P T 2008;33:

28 Tailoring Treatment for Neuropathic Pain Pharmacological recommendations: First line: pregabalin/gabapentin, SNRI, TCA Tailor treatment based on patient: Tesfaye S, et al. Diabetes Metab Res Rev 2011;27:629 Avoid TCA in patients with glaucoma, orthostatic hypotension, CVD, worried about falls and weight gain Avoid duloxetine in patients with hepatic disease and egfr < 30 Avoid pregabalin and gabapentin in patients with edema and concerned about weight gain

29 30 Combination treatment options Amitriptyline + Electrotherapy Anticonvulsant + Antidepressant Compounded Topical Treatments Insufficient evidence to support or refute Bril V et al. Neurology 2011;76:20: ; Montfort EG et al. US Pharm 2010;35(5):HS8-HS15.

30 Neuropathic Pain Medication Summary Commentary Medications and usual maintenance dose Adverse effects Goals of therapy Place in therapy Amitriptyline, desipramine, and nortriptyline: mg/day Gabapentin: 300 1,200 mg tid Pregabalin: mg bid Duloxetine: mg/day Vary based on the agent With fibromyalgia, important to start low and go slow As completely eliminating pain is not usually achievable, the goal for neuropathic pain is to make the pain tolerable Gabapentinoids (pregabalin, gabapentin), TCA, and serotoninnorepinephrine reuptake inhibitor (SNRI; duloxetine) are first line Moulin D, et al. Pain Res Manag 2014;19:328