Beverly E. Thorn - US grants

Focal brain stimulation (FBS) has been used to elicit analgesia in a variety of species, including humans with chronic pain conditions. Brain stimulation-produced analgesia (SPA) shares similarities with the opiate alkaloids, e.g., FBS and morphine-analgesia are naloxone reversible, and SPA delays the development of morphine tolerance. Repetitive FBS of the periaqueductal gray results in some naloxone-elicited signs of opiate withdrawal. Furthermore, FBS of the periaqueductal gray attenuates some opiate withdrawal behaviors in rats undergoing morphine withdrawal. The above evidence suggests that SPA may have a neuronal tie to the phenomena of opioid tolerance and dependence. Other evidence suggests neuronal separation of opiate analgesia from other opioid behaviors, including withdrawal behaviors. Studies using selective opiate receptor blockers have shown a differential ability to block morphone analgesia or the withdrawal signs depending upon the type of receptor being blocked. Researchers have also observed a differential participation of structures within the brain in the components of the morphine withdrawal syndrome. The proposed research investigates whether separation of various opiate behaviors can be demonstrated using focal brain stimulation. The experiments proposed will be conducted in three series: Series I will manipulate the brain stimulation parameters (intensity and duration of FBS) as well as electrode locus and dosage of antagonist in order to determine whether these manipulations elicit differences in the variety or severity of withdrawal behaviors observed. Series II will provide a neuroanatomical map of the substrates involved in FBS-elicited analgesia (short-term stimulation) and withdrawal (long-term stimulation). Series III will use selective opiate receptor blockers in an attempt to prevent specific opiate-like effects of the FBS.

APPLICANT?S DESCRIPTION: Cognitive-behavioral interventions are an effective component of multidisciplinary treatment for patients with pain problems. The critical components for treatment success are not known, nor is it understood why CBT works better for some patients than for others. Very few studies have evaluated the utility of specific components of CBT for pain, and the comparison of cognitive components of CBT is particularly lacking. The first aim of this study is to conduct a randomized control comparison of two cognitive-behavioral interventions for headache pain to a delayed treatment control group. The two cognitive interventions employed will be treatment focused on the reduction of pain-specific dysfunctional cognitions and treatment focused on teaching cognitive coping strategies Participants in this study will be referred by local neurologists and will meet diagnostic criteria for migraine and/or tension-type headache. Comprehensive assessments will be conducted before treatment and following 8 weeks of treatment (primary endpoint). Primary outcome measures will include: self-reported pain intensity and frequency of headaches and pain medication use. Secondary outcome variables will include measures of depression, anxiety, dysfunctional thinking, catastrophizing, cognitive coping and self-efficacy. It is predicted that patients who receive treatment will show significant treatment gains compared to the delayed treatment group. However it is expected that cognitive restructuring will result in greater treatment gains than coping skills training. The second aim of the study is to examine the effect of catastrophizing, a specific individual variable that has been shown to predict pain treatment success. Individuals who score high on measures of catastrophizing display poorer physical and psychosocial functioning. These individuals also evidence poorer response to treatment. It is hypothesized that baseline catastrophizing scores will be a predictor of treatment success. Participants who score higher on a measure of catastrophizing will show less improvement than individuals who score lower on this measure. However, catastrophizers will show greater relative improvement with cognitive restructuring than with coping skills training. Future research will consider the potential effects of combining these treatments as well as the impact of order of component presentation.

[unreadable] DESCRIPTION (provided by applicant): Individuals living in a rural area have a high occurrence of chronic pain. Cognitive Behavioral Therapy (CBT) is a widely accepted evidence-based psychosocial treatment for chronic pain; its efficacy has been well established in multiple randomized clinical trials. However, there is no research testing the treatment efficacy of psychosocial interventions for chronic pain in rural populations. The primary objective of the proposed study (R21) is to test the efficacy of CBT compared to education attention control for rural individuals with chronic pain (ICPs). Ten weekly sessions of CBT or education treatment will be provided in small group format (6-8 individuals) at two rural health clinics for patients suffering from chronic pain. Treatment implementation measures will be used to ensure that therapists are delivering the treatment as planned and that patients understand and implement the treatment suggestions. The specific aims of this study are as follows: 1) To test the efficacy of CBT group treatment for rural ICPs, we will compare CBT outcomes to an education attention control condition. We hypothesize that participants in the CBT condition will report greater improvements in pain related outcomes (pain severity, perceived disability, depression, and quality of life) than control participants. 2) To test the mediational role of catastrophizing, a negative mental set about pain, on treatment outcomes in a rural population. We hypothesize that pain catastrophizing will mediate treatment outcome measures obtained at the end of treatment. A Secondary Aim is to explore potential differences in treatment outcome and treatment-related variables (treatment satisfaction, session attendance rate, drop out rate, and the ratio of invited participants versus those who participate) based on gender, education, income, and ethnicity. Providing CBT to rural ICPs is consistent with Healthy People 2010's two overarching goals of increasing the quality and years of healthy life and eliminating health disparities (DHHS, 2000). Rural citizens have a high incidence of chronic pain problems and they lack access to health care. Although psychosocial treatments for chronic pain have proven effective in urban populations, they have not been systematically tested in rural populations. This study will test the effectiveness of cognitive-behavioral treatment for chronic pain in two rural Alabama health clinics with a high percentage of African Americans. [unreadable] [unreadable] [unreadable]