A known difficulty in pain management is the reliance on a patient’s self-reported measure of pain to guide treatment. We conducted a randomized, double-blinded, placebo-controlled crossover study to examine the utility of brain network activation (BNA) technology to quantify responses in healthy volunteers to pain induced by noxious thermal stimuli following the administration of an opioid analgesic. We examined the relationship between BNA scores and numeric pain scale (NPS) scores and compared the sensitivity, specificity and accuracy of BNA and NPS. Forty-two subjects underwent baseline electroencephalographic (EEG) measurements followed by two testing sessions after receiving placebo and two sessions after receiving 20 mg of oxycodone in a double-blinded fashion. Subjects received brief heat stimuli at 42°C, 50°C, and 52°C to the upper forearm in randomized sequences, and 128-lead EEGs were recorded. For each subject, similarity scores to a pain reference brain network model were calculated for the contact heat-evoked potentials. BNA provided an objective, sensitive, and quantitative method to measure pain perception associated with the acute noxious thermal stimulus. BNA scores revealed a statistically significant drug effect (attenuation of pain) when compared to baseline (p<0.0001) as well as to placebo (p=0.006), with similar results for NPS scores. A statistically significant association was observed between overall NPS and BNA scores, although this relationship did not hold for individual subjects. Additionally, BNA scores showed moderate to substantial repeatability (intraclass correlation coefficient 0.64 – 0.70), and differentiated between warmth and pain in a receiver operating characteristic analysis. These findings suggest that BNA may be useful not only to provide clinicians with an electrophysiological “imaging” tool to optimize treatment but also to measure treatment effect and to screen subjects for drug development studies. Supported by a grant from Purdue Pharma.
|Original language||English GB|
|Journal||The Journal of Pain|
|State||Published - 2016|