Cognitive Behavioral Therapy for Diabetic Neuropathic Pain

Research Design: A randomized controlled design will be employed in which CBT plus standard pharmaceutical care (CBT/SC) is compared to an educational intervention plus standard pharmaceutical care (ED/SC) treatment condition. A target sample size of approximately 215 participants will be recruited. Participants will be randomized in equal numbers to the two conditions.

Methodology: Study participants will be evaluated pre-treatment (baseline), 12 weeks post-baseline (post-treatment) and at 36 weeks post-baseline (follow-up). Baseline assessment will include a physical examination to confirm the diagnosis of diabetic neuropathy. The primary outcome measure will be pain intensity. Secondary outcome measures will be pain quality, pain-related disability, and physical and emotional functioning. Measures of treatment feasibility will also be examined. CBT and ED will be provided in 10 weekly, individual treatment sessions of 60 minutes. The effectiveness of the randomization process will be tested by examining potential between condition differences on important demographic and pain-relevant descriptive variables, as well as on the dependent measures. Analyses of covariance will be employed to determine whether statistically significant differences in the two treatment conditions are observed at the 12- and 36-week intervals controlling for pretreatment/baseline scores on these same measures and other covariates identified previously.

Hypotheses Treatment outcome hypotheses

• Persons with DPNP receiving cognitive behavioral therapy with standard pharmaceutical care (CBT/SC), relative to those receiving diabetic education with standard pharmaceutical care (ED/SC), will demonstrate, immediately following treatment improvements on several measures of the experience of persistent pain, including pain intensity, pain quality, pain-related disability, sleep quality, physical functioning, and emotional functioning, and they will have fewer added pain medication doses and concomitant pain treatments.
• Persons with DPNP receiving CBT/SC, relative to those receiving ED/SC, will demonstrate maintenance of these benefits at a 36-week post-baseline follow-up period.

Treatment satisfaction and feasibility hypotheses

• Persons with DPNP receiving CBT/SC, relative to those receiving ED/SC, will demonstrate, immediately following treatment higher ratings of treatment credibility and treatment satisfaction, and higher rates of treatment session attendance and lower rates of treatment dropout.

Exploratory secondary analyses of predictors of treatment participation and outcome

• Increased readiness to adopt a self-management approach will be positively associated with higher ratings of treatment credibility and treatment satisfaction, higher rates of treatment session attendance and lower rates of treatment dropout, and for participants in the CBT condition only, higher rates of adherence to therapist recommendations for pain coping skill practice and other intersession goals.
• Increased readiness to adopt a self-management approach over the course of treatment will be associated with improved outcomes following treatment.
• Increased readiness to adopt a self-management approach at treatment termination will significantly predict maintenance of treatment benefits on follow-up.
• Persons with medical and psychiatric comorbidities will demonstrate, relative to those without these comorbidities, less improved outcomes, lower rates of treatment session attendance and higher rates of treatment dropout, and for the CBT condition only, lower rates of adherence to therapist recommendations for pain coping skill practice and other intersession goals.

Inclusion criteria

• Established diagnosis of type 2 diabetes mellitus according to American Diabetes Association criteria
• History of daily lower extremity pain or discomfort (burning, tingling or other paresthesias) for a period of at least 3 months immediately prior to enrollment,
• Presence of neuropathy, as determined by evaluation at the VACHS Neuromuscular Disease and Neuropathy Clinic at the time of the baseline examination
• Judgment of the study endocrinologist (EH) that the patient is not experiencing a paradoxical precipitation of neuropathy following institution of good control which can be expected to resolve spontaneously
• Confirmation of the study neurologists that pain is not attributable to other medical conditions that could mimic DPNP (e.g., HIV, Hepatitis C, cryoglobulinemia, pernicious anemia, untreated hypothyroidism)
• Documentation of treatment of neuropathic pain with the maximum dose of one of the medications identified as a first line or second line treatment in either VA guidelines28 or other published consensus recommendations27 with maximum dose defined as either the maximum allowable dose or the maximum tolerated dose for the recommended duration of an adequate trial, unless otherwise contraindicated or patient refusal)
• Continued use of a guideline endorsed medication for neuropathic pain (unless otherwise contraindicated or patient refusal)
• Continued refractory pain despite pharmacological intervention as described above (as determined by a pain intensity score at least 4 on a 0-10 numeric rating scale)
• No medical condition that could impair the subject's ability to participate (e.g., unstable angina, severe COPD, limb amputation, intermittent claudication)
• No psychiatric condition (e.g., active substance abuse, psychosis or suicidality) that could impair subjects' ability to participate as defined by their responses to the SCID and BDI (e.g., presence of major Depressive Disorder and BDI score 30 or greater or presence of suicidal intent; presence of these conditions will require immediate medical/psychiatric attention to assure safety and institution of appropriate treatment)
• Absence of dementia defined by a score of 24 or greater on the Folstein Mini-Mental Status Exam (MMSE)
• Urine toxicology screen confirming the absence of illegal substances or non-prescribed opioids
• Provision of participant consent to consult their primary care physician and review their medical records to ensure that eligibility criteria are met,
• Availability of a touch-tone telephone in the participant's residence to facilitate the provision of IVR data
• English fluency sufficient to participate meaningfully in treatment. Prospective participants' medical and pharmacy records will be reviewed to determine whether they meet the 4th and 5th criteria listed above.

Exclusion criteria

• No history of Type 2 diabetes mellitus
• Any life threatening illnesses or acute physical disease
• Any current psychiatric condition (psychosis, substance abuse/dependence)
• Any current suicidal thoughts or ideations
• The presence of profound cognitive impairment rendering successful participation in CBT or ED impossible
• prior or current psychological treatment for chronic pain
• The presence of physical disabilities resulting in an inability to attend treatment sessions and/or inability to participate in telephone interventions (e.g., severe dysarthria)
• No access to touch tone telephone