[Distress tolerance and experience of chronic pain]

Chronic pain is a highly prevalent condition that is associated with distressing somatic and emotional experiences. Consequently, an individual's distress tolerance, the perceived capacity to tolerate negative psychological and physical states, may influence their pain experience. This effect could be explained in part by a reduction in the catastrophic interpretation of pain which is associated with increased pain intensity and interference in everyday activities.

The first aim of this study was to explore the association between the components of the 5-factor model of distress tolerance and (1) pain intensity and (2) pain interference in everyday activities. The secondary aim was to assess the potential mediating effect of pain catastrophizing in the eventual association between components of distress tolerance and (1) pain intensity or (2) pain interference in everyday activities.

This is a cross-sectional study of adult (18 years or older) university students and staff with chronic pain (3 months). They were invited to complete the online questionnaire through an email invitation. Pain intensity and interference in everyday functioning were assessed with the corresponding subscales of the Brief Pain Inventory. The following instruments were used to assess the components of the 5-factor model of distress tolerance: Ambiguity Tolerance Scale (tolerance to ambiguity), Intolerance to Uncertainty Scale (reversed score: tolerance to uncertainty), Discomfort Intolerance Scale (reversed score: discomfort tolerance), Distress Tolerance Scale (tolerance to negative emotions), Frustration Discomfort Scale (tolerance to frustration). Participants also completed the Pain Catastrophizing Scale.

Eighty participants were recruited (57 % women, mean age=33.09; standard deviation=12,87). Tolerance to negative emotions was the only component of distress tolerance that was associated with pain (ß=-0.04; 95% CI): -0.07--0.01; t (78)=-3.06, p<0.01) or pain interference in everyday functioning (ß=-0.07; 95% CI: -0.10--0.03; t (78)=-3.97, p<0.01), independently of the others. Combined with age, these factors explained 16.2 % of the variance in pain intensity and 19.4 % of the variance in pain interference. Pain catastrophizing partially mediated the association between tolerance to negative emotions and pain interference in everyday functioning, but it was not involved in the association between tolerance to negative emotions and pain intensity.

Tolerance to negative emotions appears to be the most relevant aspect of distress tolerance in the context of chronic pain and is a potential clinical target that is independent and complementary from pain catastrophizing.