Biological and psychological predictors of visceral pain sensitivity in healthy premenopausal women.
Factors that are associated with pain perception remain incompletely understood, especially in the visceral pain field. Therefore, the current study aimed to investigate possible psychological and biological predictors of visceral pain sensitivity in healthy subjects. In a sample of 59 healthy premenopausal female subjects on hormonal contraceptives, measures of gastrointestinal (GI) symptoms in daily life, trait and state anxiety, depression, serum cortisol concentrations and serum levels of interleukin-6 (IL-6) were obtained, followed by assessment of rectal distension pain sensitivity measures (i.e., rectal distension sensory threshold, pain threshold and pain ratings for discrete rectal distension stimuli). Regression analyses showed that more GI symptoms in daily life predicted a lower pain threshold. Higher levels of state anxiety predicted a lower pain threshold. Higher cortisol concentrations predicted lower pain ratings. IL-6 was positively related to GI symptoms but was a non-significant predictor of pain threshold in the multiple regression analysis. Similar to findings in patients with functional GI symptoms, we showed that subclinical GI symptoms predict visceral pain sensitivity. In line with somatic pain findings, state but not trait anxiety was found to predict visceral pain sensitivity. Our finding on serum cortisol as positive predictor of pain sensitivity might be interpreted in light of immunosuppressive effects of cortisol. Our finding on the role of IL-6 in GI symptoms is promising for understanding GI complaints in patients and needs further investigation.