The Effects of Mindfulness Meditation on Fibromyalgia-Related Pain

The purpose of this study is to examine the effects of a brief mindfulness meditation intervention on clinical and experimental pain in fibromyalgia (FM) patients as compared to a wait-list control condition. Based on prior research, investigators' working hypothesis is that this intervention will decrease the severity of FM-associated clinical pain and experimentally induced pain in comparison to pre-intervention scores and a wait-list control group. Additionally, based on prior work, investigators postulate that mindfulness meditation training will decrease a) depression, b) state anxiety, c) overall disease severity, and d) perceived stress, while increasing e) quality of sleep, and f) mindfulness skills in comparison to pre-intervention scores and the wait-list control group. Investigators will also be testing if decreases in pain ratings during meditation correspond to increases in parasympathetic activity. The relative systemic contributions of the parasympathetic and sympathetic branches of the Autonomic Nervous System (ANS) can be examined by measuring heart rate variability (HRV), or the variability in the beat-to-beat interval. Fast acting, parasympathetically-mediated high frequency (HF) changes in heart rate variability (HF HRV; 0.15-0.40 Hz) provide a reliable indicator of parasympathetic activity. Importantly, decreased HF HRV correlates with increased pain. Investigators therefore will employ psychophysical and physiological methodologies to test the hypothesis that the analgesic effects of mindfulness meditation in FM patients are associated with increases in HF HRV.

Mindfulness and FM-Related Clinical Pain The lack of clinical improvement in FM patients in response to pharmacologic therapy provides support for the development and validation of cost-effective, narcotic free, cognitive approaches to treating FM. If the benefits of mindfulness-based interventions can be realized after brief mental training, then this technique could better facilitate treatment in pain patients and become more attractive to clinicians and health insurers. To this extent, investigators have previously shown that four days (20m/d) of mindfulness meditation training in healthy subjects significantly reduced experimental pain unpleasantness by 57% and pain intensity by 40% when compared to rest. Additionally, investigators found that four days of mindfulness-based mental training significantly reduced state anxiety, and these results were realized even after one meditation session. However, it remains unclear if brief mindfulness-based mental training can reliably reduce clinical pain in FM patients. To this extent, investigators will test the efficacy of a brief, mindfulness meditation intervention on FM-related pain. Providing a short, but potentially effective intervention could offset the physical, temporal, and financial barriers to treatment in FM patients. Mindfulness and FM-Related Experimental Pain FM patients have been found to have lower pain thresholds across multiple noxious stimulation modalities and suffer from hyperalgesia, an increased sensitivity to pain. While pain thresholds correspond to the point at which a stimulus is experienced as painful, sensitivity to pain refers to an individual's subjective experience of a noxious stimulus. Unfortunately, no known studies have examined the effects of mindfulness meditation on FM-related heat pain thresholds and heat pain sensitivity. The employment of experimentally induced pain manipulations could provide the means to disentangle the constellation of interactions that affect the subjective experience of FM-related pain. To this extent, in addition to examining the effects of mindfulness meditation on clinical pain, investigators will also employ psychophysical methodologies to determine if mindfulness meditation attenuates experimentally induced pain in FM patients. Heart Rate Variability (HRV) and Fibromyalgia The Autonomic Nervous System (ANS) is critical for control of homeostatic measures such as blood pressure, body temperature, and heart rate. HRV, or the variability in the beat-to-beat interval, can be used to assess the systemic relative contributions of the parasympathetic and sympathetic branches of the ANS. Parasympathetic effects on heart rate are mediated through the vagus nerve relatively quickly, thus classifying high frequency changes in heart rate (HF HRV; 0.15-0.40 Hz) as a marker of parasympathetic activity. Interestingly, decreased HF HRV can provide a robust physiological correlate of the subjective experience of pain. In fact, decreased HF HRV is directly associated with a number of clinical pain conditions including fibromyalgia. Additionally, recent findings have shown that meditation directly increases HF HRV. Investigators therefore will employ psychophysical and physiological methodologies to test the hypothesis that the analgesic effects of mindfulness meditation in FM patients are associated with increases in HF HRV. Specific Aims To examine the effects of a brief mindfulness meditation intervention on clinical pain (the primary outcome) and experimental pain (the secondary outcome) in FM patients as compared to a wait-list control condition. Investigators will also examine if the analgesic effects of mindfulness meditation are correlated with increases in HF HRV. Hypotheses Investigators hypothesize that a brief mindfulness meditation intervention will decrease clinical and experimental pain in FM patients when compared to a wait-list control condition. Investigators hypothesize that the analgesic effects of meditation will be correlated with increases in HF HRV. Investigators also predict that meditation will decrease depression, state anxiety, overall disease severity, and perceived stress, while increasing quality of sleep, and mindfulness skills in comparison to pre-intervention scores and the wait-list control group. Study Objectives Primary Objective: The primary objective of this study is to determine if a brief mindfulness meditation intervention can improve FM-related clinical pain. Based on prior research, investigators' working hypothesis is that this intervention will decrease the severity of FM-associated pain in comparison to pre-intervention scores and a wait-list control group. Secondary Objective: The secondary objective of this study is to determine if a brief mindfulness-based meditation intervention can impact a number of factors associated with FM while proving to be a feasible intervention for this patient population, as measured by an attrition rate of less than 25%. First, investigators will test the hypothesis that mindfulness meditation, in comparison to the wait-list control group and pre-intervention experimental pain ratings, will reduce the subjective experience of experimentally induced pain in FM patients. Specifically, based on preliminary studies, investigators hypothesize that a brief mindfulness meditation intervention will decrease heat pain sensitivity and increase heat pain thresholds in this patient population (see Interventions and Interactions). Additionally, investigators will test the hypothesis that the decreases in clinical and/or experimental pain caused by mindfulness meditation will be associated with increases in HF HRV. Finally, investigators will test if a brief mindfulness-based meditation intervention can improve psychological disposition in FM patients. Based on prior work, investigators postulate that mindfulness meditation training will decrease a) depression, b) state anxiety, c) overall disease severity, and d) perceived stress, while increasing e) quality of sleep, and f) mindfulness skills in comparison to pre-intervention scores and the wait-list control group.

Training will be held in groups of up to five participants. All of the participants within this group will receive up to 6 days (20m/d) of meditation training to be administered over 15 days. This is a paradigm similar to one employed in previous studies.

Training will be held in groups of up to five participants. All of the participants within this group will receive up to 6 days (20m/d) of meditation training to be administered over 15 days. This is a paradigm similar to one employed in previous studies.

Investigators will use "pre-intervention" vs. "post-intervention" VAS overall pain ratings for the previous two weeks (those obtained from sessions 1 and 8, respectively) to test the hypothesis that a mindfulness meditation intervention will decrease clinical pain in FM patients. Investigators will employ a 2 (meditation vs. control) X 2 ("pre" vs. "post-intervention") repeated measures ANOVA (RM ANOVA) to test hypothesized differences between groups. Follow-up post-hocs will be conducted to test significant main effects and interactions.

Heat Pain Sensitivity Testing: Investigators will examine data corresponding to the pre and post intervention sessions separately. Investigators will employ a univariate ANOVA to assess if there are baseline differences in pain between groups. With respect to the post-intervention session, investigators will employ a 2 (group) X 2 (rest vs. control/meditation) RM ANOVA to test the hypothesis that meditation will reduce pain ratings when compared to rest and the control group. Follow-up post-hoc tests will be conducted to examine significant main effects and interactions. Heat Pain Threshold Testing: In order to test the hypothesis that heat pain thresholds will increase after meditation training and when compared to the wait-list control group, investigators will conduct a 2 (group) X 2 ("pre" vs. "post-intervention") RM ANOVA. Follow-up post-hocs will be conducted to test significant main effects and interactions.

Investigators will use "pre" vs. "post" ratings (those obtained at sessions 1 and 8, respectively) on the BPI, PHQ-8, CES-D, FIQR, PSS, PCS, PSQI, MASQ, and FMI to test the hypothesis that mindfulness meditation decreases a) pain-related measures, b) depression, c) disease severity d) perceived stress, and e) pain catastrophizing while increasing f) quality of sleep, g) cognitive function, and h) mindfulness ratings. Investigators will use a 2 (group) X 2 ("pre" vs. "post-intervention") RM ANOVA for each of these scales to test the hypotheses. Follow-up post-hocs will be conducted to test significant main effects and interactions.

In order to test the hypothesis that mindfulness meditation will reduce SAI scores, investigators will perform a 7 (experimental sessions employing meditation) X 2 ("pre" vs. "post") RM ANOVA where "pre" corresponds to SAI scores prior to each intervention and "post" corresponds to SAI scores after each intervention. Follow-up post-hocs will be conducted to test significant main effects and interactions.

Separate multiple regression models (one for pain intensity and one for pain unpleasantness ratings) will be conducted to test the hypothesis that the analgesic effects of mindfulness meditation will be associated with increases in HF HRV. The regression model(s) will examine if group (wait-list control; meditation) is uniquely associated with the overall model examining the proposed relationship between pain ratings and HF HRV, respectively. Investigators will conduct similar regression models for heat pain thresholds, where the temperature at which a patient first feels pain during session 8 is entered as the dependent variable in the regression model. Investigators will also conduct a similar regression model for clinical pain, where session 8 VAS ratings (intensity and unpleasantness) relating to pain over the previous 2 weeks are entered as the dependent variable, respectively.

Inclusion Criteria: Sixty individuals (18-65 years old; male and female) of all ethnic backgrounds will be examined. Participants should meet the 2010 revised American College of Rheumatology (ACR) criteria for FM. Additionally, only patients who have been on the same medication regimen for FM for the past four weeks will be included. Patients must also report a score of greater than or equal to 50 on the Revised FM Impact Questionnaire (FIQR) and a score of less than 20 on the Patient Health Questionnaire-8 (PHQ-8) to be included in the study. Importantly, Dr. Dennis Ang will confirm FM diagnoses. Exclusion Criteria: Individuals with chronic heart or lung conditions, who are pregnant, smoke, are currently waiting for a response to an application for disability, have been diagnosed with schizophrenia, bipolar, or any other mental illness or personality disorder, or are planning on undergoing any major elective surgery in the next three months will be excluded. Additionally, those patients who have ever meditated (excluding yoga) will be excluded.

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