Influence of Pain Intensity and Pain Catastrophizing on Conditioned Pain Modulation in Elderly People With and...

To investigate if psychological/cognitive aspects and executive functions can influence conditioned pain modulation (CPM) activity in elderly people with and without chronic pain.

A cross-sectional unifactorial repeated measures case-control study with 19 adults (89.5% women, age: 73.2±5.6 y) with chronic primary musculoskeletal pain and 38 adults (74.5% women, age: 74.3±4.4 y) without chronic pain was conducted. Pain features, psychological/cognitive (anxiety, depression, pain hypervigilance, and pain catastrophizing), and 2 executive functions (working memory, mental inhibition) were assessed. Subsequently, CPM was evaluated on changes obtained in mechanical (pressure pain threshold-PPT) stimuli with the cold-pressor test paradigm.

A significant group X time interaction after controlling all cofounders was found: PPTs were higher after the conditioned stimulus in individuals without chronic pain (CPM increase 15%±10%), whereas PPTs were lower after the conditioned stimulus in those with chronic pain (CPM decrease -11%±7%) when compared with PPTs at baseline. In elderly people with chronic pain, pain intensity and catastrophizing accounted for 28.6% of the variance of the CPM activation index. In elderly people without chronic pain, just pain catastrophizing had significant predictive value accounting for 10.6% of the variance of CPM activation index.

Elderly people with chronic musculoskeletal pain exhibited impaired CPM activation as compared with adults without chronic pain. Thus, CPM activation was associated with the intensity of pain and, in a lesser extent, with pain catastrophizing, but not with anxiety/depressive levels and executive functions.