Analgesics in Chronic Back Pain: The Significance of Patient Attitudes to Them and Prior Experience With Them for Placebo Responses

Patients' attitude toward and their personal experience of analgesics may not only influence their expectations about new medications they are prescribed but might also influence placebo effects. We assessed attitudes toward pain medication with an 8-item instrument and experiences with pain medication with an 11-item instrument and evaluated the relationship of attitudes and experiences and placebo responses in chronic back pain patients. On average, patients reported a slightly negative attitude toward analgesics and a slightly positive experience with them compared to healthy pain-free controls that had a more positive attitude toward and experience of analgesics. Pain patients seemed to report their short-term experience with analgesics when completing our instrument, as can be seen by the regression of experience with pain medication and the subscale short-term efficacy of non-/minimally invasive pain medication of the pain interview. Using a pharmacological placebo in a subsample of 38 patients, we were able to show that patients with positive attitudes had a larger placebo response than patients with negative attitudes. The size of the placebo response could be predicted using the mean attitude score. Future placebo research assessing patients' attitudes toward analgesics seems important and could help to understand the results obtained.