The effects of pain medication on sleep and sensory testing
Research type
Research Study
Full title
The effect of analgesic medication on measures of sleep disturbance and quantitative sensory testing, a pragmatic, observational feasibility study.
IRAS ID
156442
Contact name
Jonathan C.W. Brooks
Contact email
Sponsor organisation
University of Bristol
Research summary
Chronic pain is a debilitating illness frequently treated with opioids, such as morphine, prescriptions for which have risen substantially in the UK over the last decade. Research indicates that opioids can substantially disrupt sleep physiology, depressing breathing during the night and altering electrical activity recorded from the brain. In this study will investigate if opioid medications (1) contribute to sleep disturbance, and (2) paradoxically increase acute pain sensitivity, which may contribute to chronic pain conditions. In this cross-sectional feasibility study we will explore these questions, by recruiting two groups of chronic back pain patients: those on no, or low, doses of opioids and those on moderate to high doses (>50mg). We will assess rest/activity patterns over 2 weeks using a small wrist worn accelerometer and self-completed diary. Patients will then be invited to attend two consecutive nights sleep monitoring and sensory testing. During sensory testing hot, cold, pin-prick and brush stimuli will be applied to the arm, and patients asked to rate whether they feel the stimulus and how intense it is, and if it is painful. None of the stimuli used in this study are skin damaging. Patients’ ability to suppress pain signals will be tested by immersing their hand in ice-cold or warm water, and they rate the intensity of a painful hot stimulus applied to the opposite arm. A small subset of patients will be invited to participate in a brain imaging study (using magnetic resonance imaging, “MRI”), where we will examine their brain responses to a painful thermal stimulus, to explore whether patients taking opioids have altered brain responses to pain. We will ask all patients if they would be interested in coming back for a single night’s study should they substantially alter their medication within a 6 month period following their initial visit.
REC name
South West - Frenchay Research Ethics Committee
REC reference
14/SW/1002
Date of REC Opinion
18 Aug 2014
REC opinion
Further Information Favourable Opinion