Exploring the management of painful diabetic neuropathy

We know that diabetes, and the complications that may accompany it, are becoming more common [1]. A World Health Organisation study looking at the Disability Adjusted Life Years for a range of diseases showed that globally diabetes has risen from 21st in 1990, to 14th in 2010; ischaemic heart disease was ranked 1st [2]. Painful diabetic neuropathy (PDN) is one of the potential complications of diabetes and affects 6-34% of people with diabetes [3]. PDN is an unpleasant burning pain condition that is unpredictable and can have a large impact on people’s physical ability, mood state and overall quality of life [3].

Recommendations for the management of PDN do not go beyond drug management [4], and we know that these drugs often fail to provide significant pain relief [5]. My PhD [6] explored whether strategies from pain management programmes (PMP) might be appropriate for people with PDN. PMP strategies include physical activity and psychological coping skills and many professions working with people in persistent pain use these approaches.

We conducted a systematic review of the available evidence for the use of PMP strategies with PDN. We searched for studies that used any intervention that could be defined as a physical activity and any psychological intervention that would promote coping with persistent pain [7]. We were primarily interested in the effect of these interventions on pain experienced, so included only randomised trials that used pain scores as an outcome. To be honest, the evidence base came up short.

Two studies investigating physical exercise found inconsistent results. A randomised trial of aerobic exercise (n=47), compared to treatment-as-usual (n=40, received advice on foot care), did not improve pain [8]. The statistically significant results presented were due to the control arm worsening. A block-randomised trial investigating Tai Chi (n=20) compared to routine education on diabetes (n=19), found some improvements in pain severity but worsening pain in the control arm again contributed to this statistical significance [9]. These two studies are not an evidence base but could it be that people with PDN have to move more, in terms of exercise, in order to stand still in terms of pain experience?

The search for psychological coping strategies found only two studies: a study of mindfulness meditation [10], and a CBT-based pain course [11]. Small numbers of participants and high rates of drop out affected the quality of these studies and no firm conclusions could be made.

Overall, there is currently a scarcity of evidence for the use of PMP strategies in PDN. Considering the cost of PDN to the person as well as health services (the UK annual cost averages £2511 per patient, with drugs accounting for around 30% of this amount [3]), you might expect more research into non-drug treatment options.

We wanted to further explore peoples’ experiences of PDN and their views on whether PMP strategies might be of relevance to them. We conducted one-to-one interviews with twenty-three people and found PDN had a wide range of impacts on their lives. For example, PDN affected their sex lives, made them embarrassed for having pain with no clear cause and impacted on their appetite (with further consequence on their diabetes management). The scope of identified impacts were more varied than has been captured using quantitative questionnaires [3]. Importantly, there was scepticism about how physical activity or psychological approaches could be beneficial for PDN. Some interviewees were clear their pain was due to ‘nerve damage’ and exercise or ‘talking to someone’ had no relevance to their experience. Others, who had attended PMPs for other reasons such as low back pain, felt that these strategies did have applicability to PDN.

We also interviewed specialist diabetes clinicians (n=10), specialist pain clinicians (n=6) and representatives from primary care (n=2). The diabetes clinicians were aware of the range of impacts experienced by people with PDN, yet they described few strategies beyond medication to manage these impacts. Diabetes clinicians felt that people with PDN were at risk of foot damage if excessive physical activity was advised and that people with diabetes were medically more complex than the ‘usual’ participants in a PMP.

Pain specialist clinicians described many PMP strategies could have application in people with PDN. They were aware some strategies (e.g. pacing) may not be easily applied and so novel strategies maybe required. This finding was supported by other research, for instance Daniel et al. [12] described difficulty accommodating the specific needs of people with neuropathic pain in ‘standard’ PMPs. Pain clinicians were cognisant of the risks physical activity could pose to insensate feet but had other non- or partial-weight bearing exercise options available to minimise that risk.

So, it may have been possible to design and pilot a PMP bespoke for PDN. Yet we felt it would be more productive to return to the population with PDN and ask them what were their priorities? Of all the ways in which PDN affected their lives what did they most want help to manage better? Using the 58 impacts identified in the interview data, we created an Internet study to explore the respondents’ priorities.

There was consistency, but not universality, in the impacts respondents (n=78) prioritised for improved management. Sleep disturbance was consistently rated the top priority. Other top priorities were numb feet, worry for the future, loss of physical fitness and depression. Impacts that reflected the subjective pain experience of PDN were not prioritised. This suggests that when presented with options developed from the experience of people with PDN, pain reduction was not necessarily the most important priority for treatment. Clinicians in the field of pain, may need to be more inquisitive and open to the priorities patients bring to their consultations.

For some of these priorities there are existing evidence-based treatments, such as cognitive behavioural approaches for insomnia [13]. There is emerging evidence for acceptance-based approaches from other neuropathic pain conditions (multiple sclerosis) which may be applicable to PDN [14]. And there is no evidence that any approach, including medications, can reduce numbness in the feet; the only strategy is not to develop neuropathy in the first place.

This series of studies has shown that PMPs as currently implemented may not provide appropriate, adequate or desired help for people with PDN. A possible next step would be to ensure clinicians involved with diabetes and PDN are trained in eliciting the patient priorities and are then able to guide people to existing management strategies (where available) that address these. This would require raising the profile of pain management strategies with the wider multi-disciplinary diabetes team.

This doctorate was supervised by Professor Candy McCabe, Professor Fiona Cramp and Dr Jeremy Gauntlett-Gilbert (University of the West of England, UK).

About Ben Davies

Ben Davies UK NoiAs an NOI Instructor in the UK, I have taught MONIS, EP and GMI courses in the UK and beyond since 2008. My background as a physiotherapist involves primary, secondary and tertiary care settings. The majority of my experience is with people who have complex, persistent pain presentations. Currently I work in primary care for Virgincare (Bath and Northeast Somerset, UK) as professional lead for physiotherapy and clinical specialist physiotherapist in pain management.

My PhD at the University of the West of England was in painful diabetic neuropathy, exploring whether this group of people could benefit from pain management approaches which are common in the MSK pain world, but not in the diabetic world.

You can find me on twitter (@ben_davies42), although I tend to use free time trying to ride my bike and get back out into the mountains.

References

[1] Alberti KGMM, Zimmet P. Epidemiology: Global burden of disease—where does diabetes mellitus fit in? Nature Reviews Endocrinology. 2013;9(5):258–60.

[2] Murray CJL, Vos T, Lozano R, Naghavi M, Flaxman AD, Michaud C, et al. Disability-adjusted life years (DALYs) for 291 diseases and injuries in 21 regions, 1990-2010: a systematic analysis for the Global Burden of Disease Study 2010. The Lancet. 2012;380(9859):2197–223.

[3] Alleman CJM, Westerhout KY, Hensen M, Chambers C, Stoker M, Long S, et al. Humanistic and economic burden of painful diabetic peripheral neuropathy in Europe: A review of the literature. Diabetes Research and Clinical Practice. 2015 Aug;109(2):215–25.

[4] NICE. Neuropathic pain – pharmacological management. CG173. Centre for Clinical Practice at NICE. London; 2013;

[5] Moore RA, Derry S, Eccleston C. Expect analgesic failure; pursue analgesic success. British Medical Journal. 2013;2690(May):7–9.

[6] Davies B. Painful diabetic neuropathy: Exploring management options. University of the West of England; 2017.

[7] Davies B, Cramp F, Gauntlett-Gilbert J, Wynick D, McCabe C. The role of physical activity and psychological coping strategies in the management of painful diabetic neuropathy – A systematic review of the literature. Physiotherapy. 2015 Dec;101(4):319–26.

[8] Dixit S, Maiya A, Shastry B. Effect of aerobic exercise on quality of life in population with diabetic peripheral neuropathy in type 2 diabetes: a single blind, randomized controlled trial. Quality of Life Research. 2014 Jun;23(5):1629–40.

[9] Ahn S, Song R. Effects of Tai Chi exercise on glucose control, neuropathy scores, balance, and quality of life in patients with type 2 diabetes and neuropathy. Journal of Alternative and Complementary Medicine. 2012;18(12):1172–8.

[10] Teixeira E. The effect of mindfulness meditation on painful diabetic peripheral neuropathy in adults older than 50 years. Holistic Nursing Practice. 2010 Jan 1;24(5):277–83.

[11] Otis JD, Sanderson K, Hardway C, Pincus M, Tun C, Soumekh S. A randomized controlled pilot study of a cognitive-behavioral therapy approach for painful diabetic peripheral neuropathy. The Journal of Pain. 2013 May;14(5):475–82.

[12] Daniel HC, Denney D, Corcoran K, Colbeck D, Williams A. Consider adapting pain management progammes for people with persistent neuropathic pain. In: IASP Neuropathic Pain SIG Conference. Nice; 2015.

[13] Trauer JM, Qian MY, Doyle JS, Rajaratnam SMW, Cunnington D. Cognitive behavioral therapy for chronic insomnia: A systematic review and meta-analysis. Annals of Internal Medicine. 2015;163(3):191–204.

[14] Harrison A, McCracken L, Bogosian A, Moss-Morris R. Towards a better understanding of MS pain: A systematic review of potentially modifiable psychosocial factors. Journal of Psychosomatic Research. Elsevier B.V.; 2015 Jan;78(1):12–24.