Neuropathic pain: - Affects 1-8% of the general population, but is more common in specific groups like those with diabetes, HIV, or spinal cord injuries. - Has a significant negative impact on quality of life, mobility, employment, and mental health for those affected. - Places a large burden on healthcare systems and society. The prevalence of neuropathic pain is expected to rise due to increasing rates of conditions like diabetes mellitus.

1. Neuropathic pain
Peter Kamerman
XXII World Congress of Neurology, Santiago, Chile, 2015
EPIDEMIOLOGY, RISKS, AND PREVENTION

2. Disclosures
I have no actual or potential conflicts of interest related to the material
being presented.
Nor do I discuss off-label indications for any medications.

3. Learning objectives
By the end of this presentation, delegates will be able to:
● Describe the burden of chronic pain in the general population;
● Report the proportion of chronic pain that is neuropathic in origin;
● Describe the prevalence of neuropathic pain in special populations;
● Appraise the socio-economic consequences of having neuropathic pain.

4. Key message
Neuropathic pain:
● Is common, especially in special populations (e.g., diabetes, HIV,
spinal cord injury);
● Has a significant negative impact on the affected individual, and
society

5. What is epidemiology?
“The study of the distribution and
determinants of health-related states
or events in specified populations, and
the application of this study to control
health problems.”
Last, 1995

6. Epidemiology and neuropathic pain
Adapted from: Smith and Torrance, 2012
To inform understanding, at a population level, of:
Prevalence and incidence
Risk factors and aetiology
Impact on quality of life and prognosis
Prevention
Design, targeting, and evaluation of treatment strategies
Allocation of health resources
Allocation of educational resources

7. Epidemiology and neuropathic pain
To inform understanding, at a population level, of:
Prevalence and incidence
Risk factors and aetiology
Impact on quality of life and prognosis
Prevention
Design, targeting, and evaluation of treatment strategies
Allocation of health resources
Allocation of educational resources
Predictions on the future
Adapted from: Smith and Torrance, 2012

8. Prevalence of neuropathic pain

9. How common is chronic pain?
Breivik et al., 2004
Bootstrap mean and 95% CI (data available at https://github.com/kamermanpr)
Chronic pain prevalence in 46,394 adults from 15 European countries and Israel
Pain on most days within the last 6 months

10. How common is chronic pain?
Breivik et al., 2004; Nahin, 2015
Bootstrap mean and 95% CI (data available at https://github.com/kamermanpr)
Pain on most days within the last 6 months
Chronic pain prevalence in 8,466 adults from the US
Pain on most days within the last 3 months

11. How much of chronic pain is neuropathic?
Breivik et al., 2004
Source of chronic pain in a subset of 4,389 / 46,394 Europeans with chronic pain

12. Neuropathic pain in the general population
Torrance et al., 2007; Bouhassira et al.,2008; Toth et al., 2009;
Yawn et al., 2009; de Moraes Vieira et al., 2012; Harifi et al., 2013
Median (9%)

13. How good are the data?

14. Imperfect tools provide poor estimates of true prevalence

15. Imperfect tools provide poor estimates of true prevalence
Bouhassira et al.,2008; Stevenson et al., 2015
Imperfect screening tools
Modelling based on:
● DN4 Interview
○ sensitivity = 82%
○ specificity = 86%
● n = 3000

16. Imperfect tools provide poor estimates of true prevalence
Imperfect screening tools
DN4-interview:
● Sensitivity = 82%
● Specificity = 86%
S-LANSS:
● Sensitivity = 75%
● Specificity = 80%
Torrance et al., 2007; Bouhassira et al.,2008; Toth et al., 2009;
Yawn et al., 2009; de Moraes Vieira et al., 2012;
Harifi et al., 2013; Stevenson et al., 2015

17. The burden of neuropathic pain

18. The burden of neuropathic pain
“17% of people with neuropathic pain
rated their quality of life as being,
worse than death.”
Torrance et al., 2013

19. The burden of pain varies according to cause
Not everyone with damage to the nervous system has pain
Veves et al., 2007; Sadosky et al., 2008;
Haanpaa et al., 2009; van Hecke et al., 2014

20. The burden of neuropathic pain
Schaefer et al., 2014a
Dysfunction is similar across aetiologies

21. The burden of neuropathic pain
Doth et al., 2010; Attal et al., 2011; Torrance et al., 2013;
Schaefer et al., 2014a
Chronic pain
● Reduced mobility
● Reduced quality of life
● Reduced sleep / sleep quality
● Increased unemployment
● Increased work impairment
● Increased depression / anxiety
● Increased use of healthcare
NEUROPATHIC PAIN
● Reduced mobility
● Reduced quality of life
● Reduced sleep / sleep quality
● Increased unemployment
● Increased work impairment
● Increased depression / anxiety
● Increased use of healthcare

22. The burden of neuropathic pain
Lalli et al., 2013
Attribute Diabetes
(%; n = 20)
Diabetes +
Neuropathy
(%; n = 20)
Diabetes +
Neuropathic pain
(%; n = 20)
Fell in the last year 15 20 45
Fear of falling 5 20 64
Presence of pain increases gait variance, number of fall, and fear of falling:

23. The burden of neuropathic pain
Schaefer et al., 2014b
The effect on work productivity is related to pain intensity
(n = 624 people clinically diagnosed with neuropathic pain, 33 study sites, 45% recruitment rate)

24. Burden of neuropathic pain
van Hecke et al., 2014
Risk factors for neuropathic pain:
○ Diseases/exposures that increased risk of nervous system injury
○ Female sex
○ Older age
○ Lower socio-economic status
○ Employment status and occupational factors
○ History of abuse/interpersonal violence
○ Genetic vulnerability
○ Acute pain burden
○ Psychological factors

25. The future

26. The future
Oxman et al., 2008; Ellis et al., 2010; Kamerman, 2015
Decreasing HIV-SN? Decreasing Zoster?

27. The future
Veves et al., 2007; Gauriguata et al 2013
But….increasing diabetes mellitus

28. Summary
Neuropathic pain:
● Affects 1-8% of the adult population;
● Is more common in specific patient populations (e.g., diabetes, HIV, spinal
cord injury);
● Has a significant, negative impact on the affected individual, and society;
● Resulting from diabetes mellitus could reach epidemic levels.

29. Selected reading
Bibliography
Breivik H, Collett B, Ventafridda V, et al. Survey of chronic pain in Europe: Prevalence,
impact on daily life, and treatment. European Journal of Pain 10: 287-287, 2005. doi:
10.1016/j.ejpain.2005.06.009.
van Hecke O, Austin SK, Khan RA, et al. Neuropathic pain in the general population: A
systematic review of epidemiological studies. PAIN 155: 654-662, 2013. doi: 10.1016/j.pain.
2013.11.013.
Smith BH, Torrance N. Epidemiology of Neuropathic Pain and Its Impact on Quality of Life.
Current Pain and Headache Reports 16: 191-198, 2012. doi: 10.1007/s11916-012-0256-0.