Resources
Severe pain is associated with critical illness and mortality in hospitalised patients across Africa: a point prevalence study of 22 African nations.
GJ Bedwell, R Parker, VJ Madden, J Scribante, M Elhadi, AO Ademuyiwa...[APPRISE group] and B Biccard. Preprint.
Many people in hospital have pain, but does pain change how they fare? This multicenter study found that patients in African hospitals who had severe pain were more likely to have critical illness or die within 7 days than patients who did not have severe pain.
We have submitted it for peer review; in the meantime, here is the preprint!
Provoked cytokine response is not associated with distress or induced secondary hyperalgesia in people with suppressed HIV.
VJ Madden, L Mqadi, G Arendse, GJ Bedwell, N Msolo, M Lesosky, MR Hutchinson, JG Peter, A Schrepf, R Parker, RR Edwards, JA Joska. PAIN (in press)
Psychological distress is associated with persistent pain severity, but how? With this work, we wanted to find out whether subtle changes in inflammatory responses could be responsible. We hypothesised that distress may prime the inflammatory system, thus increasing likelihood of pain persistence.
This study took the first steps to investigating this, in people with virally suppressed HIV. Our results were surprising, even to us!
Inflammatory reactivity is unrelated to childhood adversity or provoked modulation of nociception.
GJ Bedwell, L Mqadi, P Kamerman, MR Hutchinson, R Parker, VJ Madden. PAIN (in press).
People who have experienced a particularly difficult childhood are more likely to develop persistent pain – but why? Some evidence suggests that these people also commonly have hypersensitivity in immune responses. Other evidence suggests that persistent pain is linked to hypersensitivity in the nervous system. And we know that the immune and nervous systems interact.
We wondered whether a hypersensitive immune system in people with childhood adversity contributes to hypersensitivity in the nervous system, increasing risk of persistent pain. This study tested this idea, and had unexpected results that highlight the importance of conducting more research in diverse settings, especially in Africa.
A systematic review and meta-analysis of pharmacological methods to manipulate experimentally induced secondary hypersensitivity.
GJ Bedwell, L Mqadi, R Parker, PC Chikezie, P Moodley, PR Kamerman, MR Hutchinson, ASC Rice, VJ Madden. PAIN (in press).
Our nervous systems protect us, but they can become overprotective or 'hypersensitive'. We wanted to understand the processes that cause this hypersensitivity. Because we know how certain medicines work, and because we can induce a shortlived (experimental) version of this hypersensitivity, we can test which medicines interfere with the hypersensitivity to work out which processes cause it.
In this review, we collated all the published evidence on this question, in an effort to clarify the physiology underlying secondary hypersensitivity (also called 'secondary hyperalgesia') in humans.
The sensory and affective components of pain: are they differentially modifiable dimensions or inseparable aspects of a unitary experience? A systematic review.
K Talbot, VJ Madden, SL Jones, GL Moseley. British Journal of Anaesthesia 123 (2), e263-e272. doi: 10.1016/j.bja.2019.03.033
Is pain really an experience with many parts? Is it possible to separate the sensation from the emotional feeling of pain? This review pulled together all the experimental studies that have tried to tease pain into these components to find out what the scientific evidence says about whether pain can be separated into components. This is a complex but accessible discussion with important implications for what we understand pain to be.
Variability in Experimental Pain Studies: Nuisance or Opportunity?
VJ Madden, PR Kamerman, MJ Catley, V Bellan, LN Russek, D Camfferman, and GL Moseley. British Journal of Anaesthesia 126(2):e61-e64. doi: 10.1016/j.bja.2020.10.033
Many pain researchers use averages and group patterns to describe the information they collect from people who participate in pain experiments. But when we look at group patterns, we miss the patterns within each person’s reports of pain. Those patterns might be important, considering that people who seek treatment for pain don’t want treatment that works for a group; they want treatment that will work for themselves - for an individual. We wrote this commentary to remind other pain researchers to think about this when we report the data we gather in experiments.
Chronic pain in people with HIV: a common comorbidity and threat to quality of life
VJ Madden, R Parker, BR Goodin. Pain Management 10 (4), 253-260. doi: 10.2217/pmt-2020-0004
Many people who live with HIV report chronic pain that limits their daily life - but why is pain so common and so problematic for these people? This review briefly summarises what we do and don’t know about HIV-related pain.
The influence of a manipulation of threat on experimentally-induced secondary hyperalgesia
GJ Bedwell, C Louw, R Parker, E Van den Broeke, JWS Vlaeyen, GL Moseley, and VJ Madden. PeerJ 10, p.e1351
Threat influences pain - but how? Our group is developing ways to ask this question with strong science. This study tested whether threat changes the sensitivity of neural signalling about potentially dangerous events - and encountered some significant hurdles along the way.
A systematic review and meta-analysis of non-pharmacological methods to manipulate experimentally induced secondary hypersensitivity.
GJ Bedwell, PC Chikezie, FT Siboza, L Mqadi, ASC Rice, PR Kamerman, R Parker, and VJ Madden. Journal of Pain 24(10), 1759-1797.
Neural signals are constantly being adjusted inside our bodies; our systems can turn the volume of signalling up or down. Some research suggests that an impaired ability to suppress danger signals can contribute to problematic pain. In this work, we reviewed studies that had used a particular lab-based technique to induce excessive danger signalling - experimentally induced secondary hypersensitivity - and tested a non-drug intervention’s ability to control that signalling. We wanted to understand which non-drug interventions have the potential to improve a person’s ability to suppress excessive danger signals.
A pain textbook written for sharing
Edited by Romy Parker and Jocelyn Park-Ross
Understanding Pain: Unravelling the physiology, assessment, and management of pain through South African
This open access textbook integrates essential evidence-based knowledge of pain with contextual and poignant narratives from people who have experienced pain firsthand. The voices and perspectives of co-authors with lived experience of pain are positioned centrally, so that clinical learning is grounded in understanding and empathy, even as it shaped by scientific rigour.
Coming soon...
Keep an eye out for our qualitative work on living with persistent pain and HIV. We expect to have it ready in preprint form in July 2025!