Laboratory pain perception and clinical pain in post-menopausal women and age-matched men with osteoarthritis: relationship to pain coping and hormonal status.

The present study examined relationships between pain coping, hormone replacement therapy, and laboratory and clinical pain reports in post-menopausal women and age-matched men with osteoarthritis. Assessment of nociceptive flexion reflex threshold was followed by an assessment of electrocutaneous pain threshold and tolerance. Participants rated their arthritis pain using the Arthritis Impact Measurement Scales. To assess pain coping, participants completed measures of emotion-focused coping, problem-focused coping, and pain catastrophizing. Results indicated that women were more likely than men to report using emotion-focused pain strategies, and that emotion-focused coping was associated with more arthritic pain and lower electrocutaneous pain tolerance. Correlations between coping measures and pain reports revealed that catastrophizing was associated with greater arthritis pain and lower pain threshold and tolerance levels. However, catastrophizing was not related to nociceptive flexion reflex threshold, suggesting that the observed relationship between catastrophizing and subjective pain does not rely on elevated nociceptive input. A comparison of men (n=58), post-menopausal women receiving hormone replacement therapy (n=32), and post-menopausal women not receiving hormone replacement therapy (n=42) revealed no significant group differences in arthritis pain, electrocutaneous pain threshold or tolerance, or nociceptive flexion reflex threshold. Thus, older adults with osteoarthritis do not exhibit the pattern of sex differences in response to experimental pain procedures observed in prior studies, possibly due to the development of disease-related changes in pain coping strategies. Accordingly, individual differences in clinical and experimental pain may be better predicted by pain coping than by sex or hormonal differences.