Journal of Pain Research (Oct 2020)
Multisensory Sensitivity is Related to Deep-Tissue but Not Cutaneous Pain Sensitivity in Healthy Individuals
Abstract
Dan Wang,1 Shannon L Merkle,2 Jennifer E Lee,3,4 Kathleen A Sluka,1 Barbara Rakel,4 Thomas Graven-Nielsen,5 Laura A Frey-Law1 1Department of Physical Therapy and Rehabilitation Science, Carver College of Medicine, University of Iowa, Iowa City, IA, USA; 2United States Army Research Institute of Environmental Medicine (USARIEM), Natick, MA, USA; 3Department of Psychology, Mount Mercy University, Cedar Rapids, IA, USA; 4College of Nursing, University of Iowa, Iowa City, IA, USA; 5Center for Neuroplasticity and Pain (CNAP), SMI, Aalborg University, Aalborg, DenmarkCorrespondence: Laura A Frey-LawDepartment of Physical Therapy and Rehabilitation Science, Carver College of Medicine, University of Iowa, 1-252 Medical Education Bldg., 500 Newton Road, University of Iowa, Iowa City, IA 52242, USATel +1 319-335-9804Fax +1 319-335-9707Email [email protected]: Some individuals with chronic pain find daily life sensations (eg, noise, light, or touch) aversive. This amplification of multisensory sensations has been associated with centrally mediated plasticity; for example, greater multisensory sensitivity (MSS) occurs in patients with fibromyalgia than rheumatoid arthritis. However, whether MSS preferentially relates to pain measures which reflect central influences (eg, dynamic quantitative sensory testing (QST) or referred pain), or whether the MSS-pain relationship requires priming from chronic pain, is unknown. Thus, this cross-sectional study investigated the relationships between MSS assessed in a pain-free state and evoked pain sensitivity.Methods: Experimental intramuscular infusion pain and multiple static and dynamic QST were assessed in 465 healthy, pain-free adults: pain thresholds using pressure (PPTs) and heat (HPTs), temporal summation of pain (TSP) using pressure, heat or punctate stimuli, and conditioned pain modulation (CPM) using pressure or heat test stimuli. MSS was assessed using 7 items from Barsky’s Somatosensory Amplification Scale. Differences in pain and QST between sex-specific MSS quartiles were assessed, adjusting for multiple comparisons. All participants completed at least one intramuscular infusion condition, but not all were asked to complete each QST (n=166-465).Results: Both static and dynamic QST differed between highest and lowest MSS quartiles using pressure stimuli: lower PPTs (adjusted-p< 0.01); increased pressure TSP (adjusted-p=0.02); lower pressure CPM (adjusted-p=0.01). However, none of the heat or punctate QST measures (HPTs, TSP, or CPM) differed between MSS quartiles (adjusted-p> 0.05). Odds of experiencing TSP or referred pain was not greater, whereas CPM was 8-fold less likely, in those with highest MSS.Conclusion: Normal variation in non-noxious MSS is related to both static and dynamic pain sensitivity, without sensitization associated with chronic pain, but is dependent on the QST stimulus. Thus, common influences on MSS and pain sensitivity may involve central mechanisms but are likely more complex than previously recognized.Keywords: pain sensitivity, somatosensory amplification scale, experimental muscle pain, quantitative sensory testing, temporal summation of pain, conditioned pain modulation
