Pain in the body. Altered interoception in chronic pain conditions: A systematic review

Interoception is the sense of the physiological condition of the body. Modern definitions differentiated three separated sub-constructs: accuracy (IAc), i.e., the ability to detect physiological states, sensibility (IAs), i.e., a self-evaluated measure of interoception, and awareness (IAw) i.e., a metacognitive awareness of the accuracy. Preliminary researches correlated pain with alterations in the interoceptive matrix albeit, to the best of our knowledge, interoceptive alterations in chronic pain conditions have never been studied systematically. We searched for studies that assessed interoception in subjects with chronic pain and compared it to healthy population. Eleven studies were included among different chronic pain conditions. Results suggested that chronic pain subjects might present low IAc and, allegedly, that IAc negatively correlates with symptoms severity in specific disorders. Data were inconclusive for IAs and IAw. The high risk of bias across multiple dimensions suggests to consider these conclusions with cautions. Nonetheless, deficits in interoceptive processes indicate a promising path for new form of therapies, and they require further attention and a more defined line of research.