(180) Quantitative sensory testing: a population based study of adolescents with and without chronic pain

Abstract

Quantitative sensory testing (QST) has emerged as a modality for examining responses to somatosensory stimuli. However, little data is available in pediatric populations to understand whether youth demonstrate a differential response to QST when they have chronic pain. Data on QST may extend our understanding of the pathophysiology underlying the persistence of pediatric pain. Using a population-based sample, this study compared QST values in adolescents with and without chronic pain. We hypothesized that adolescents with chronic pain would have altered QST compared to adolescents without chronic pain. We conducted secondary data analyses using a population-based sample of 1038 adolescents recruited from the first year of high school in two Scandinavian municipalities. Adolescents reported on chronic pain characteristics and underwent a QST protocol (pressure- and heat-pain threshold and tolerance, cold pressor endurance). Adolescents 16-19 years old (males=51.4%) were included and classified either as not having chronic pain (n=741) or as having chronic pain (weekly pain lasting ≥3months; n=197). T tests examined group differences on QST variables. As hypothesized, adolescents with persistent pain had lower shoulder pressure pain threshold (M=767kPa, SD=223 vs M=785kPa, SD=210) and tolerance (M=266kPa, SD=130 vs M=289kPa, SD=132) compared to healthy adolescents (p’s=0.05). However, mean heat-pain threshold and tolerance were not different between groups. There was a trend for groups to differ in rates of reaching the max tolerance time (106 seconds) for the cold pressor endurance task (45.2% of adolescents with chronic pain vs 51.2% of adolescents without chronic pain, p=0.08). Our findings identified several differences in pain sensitivity on QST between adolescents with and without chronic pain. However, a strong pattern of differences between groups across modalities was not supported. Future research is needed in clinical pain samples and with other modalities and anatomical locations in order to better understand adolescent responses to experimental pain protocols. Quantitative sensory testing (QST) has emerged as a modality for examining responses to somatosensory stimuli. However, little data is available in pediatric populations to understand whether youth demonstrate a differential response to QST when they have chronic pain. Data on QST may extend our understanding of the pathophysiology underlying the persistence of pediatric pain. Using a population-based sample, this study compared QST values in adolescents with and without chronic pain. We hypothesized that adolescents with chronic pain would have altered QST compared to adolescents without chronic pain. We conducted secondary data analyses using a population-based sample of 1038 adolescents recruited from the first year of high school in two Scandinavian municipalities. Adolescents reported on chronic pain characteristics and underwent a QST protocol (pressure- and heat-pain threshold and tolerance, cold pressor endurance). Adolescents 16-19 years old (males=51.4%) were included and classified either as not having chronic pain (n=741) or as having chronic pain (weekly pain lasting ≥3months; n=197). T tests examined group differences on QST variables. As hypothesized, adolescents with persistent pain had lower shoulder pressure pain threshold (M=767kPa, SD=223 vs M=785kPa, SD=210) and tolerance (M=266kPa, SD=130 vs M=289kPa, SD=132) compared to healthy adolescents (p’s=0.05). However, mean heat-pain threshold and tolerance were not different between groups. There was a trend for groups to differ in rates of reaching the max tolerance time (106 seconds) for the cold pressor endurance task (45.2% of adolescents with chronic pain vs 51.2% of adolescents without chronic pain, p=0.08). Our findings identified several differences in pain sensitivity on QST between adolescents with and without chronic pain. However, a strong pattern of differences between groups across modalities was not supported. Future research is needed in clinical pain samples and with other modalities and anatomical locations in order to better understand adolescent responses to experimental pain protocols.