Objective: Premenstrual dysphoric disorder (PMDD) is associated with increased pain, but there has been a lack of well-controlled research assessing pain responsivity, sex hormones, and their relationships in this group. This study was designed to address this gap in the literature.
Materials and Methods: Healthy, regularly cycling participants (14 PMDD, 14 non-PMDD) attended pain testing sessions during the mid-follicular, ovulatory, and late-luteal phases of the menstrual cycle (order counterbalanced) and salivary estradiol, progesterone, and testosterone were assessed at each testing session. Pain sensitivity was measured from electrocutaneous threshold/tolerance, ischemic threshold/tolerance, sensory and affective ratings of electrocutaneous and ischemic stimuli, and the nociceptive flexion reflex threshold (NFR, a measure of spinal nociception).
Results: Women with PMDD had higher sensory pain ratings of electrocutaneous stimuli and trends for lower ischemic thresholds and higher affective pain ratings of electrocutaneous stimuli. However, there were no group differences observed in NFR threshold. Testosterone levels were also lower during the mid-follicular and ovulatory phases in PMDD. Correlations between pain outcomes and estradiol and testosterone indicated that these hormones are hypoalgesic, with estradiol having a greater hypoalgesic effect within the PMDD group.
Discussion: Overall, women with PMDD may have a phase-independent hyperalgesia, with pain amplification likely occurring at the supraspinal level rather than the spinal level, given the lack of group differences in NFR threshold. Because testosterone was hypoalgesic and lower in women with PMDD, and there were strong associations between pain and estradiol in PMDD, sex hormones may play a role in PMDD-related hyperalgesia.
Department of Psychology, University of Tulsa, Tulsa, OK
Supported by a Grant (HR09-080) from the Oklahoma Center for the Advancement of Science and Technology (OCAST) awarded to J.L.R. The authors declare no conflict of interest.
Present address: Emily J. Bartley, PhD, College of Dentistry, Pain Research and Intervention Center of Excellence, University of Florida, Gainesville, FL.
Reprints: Jamie L. Rhudy, PhD, Department of Psychology, University of Tulsa, 800 South Tucker Drive, Tulsa, OK 74104 (e-mail: email@example.com).
Received September 3, 2013
Received in revised form May 14, 2014
Accepted April 17, 2014