Clinical trial NCT02363803: Lidocaine for Diabetic Peripheral Neuropathy
Official title: Predicting Individual Response to Analgesic Treatment in Painful Diabetic Neuropathy
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Diabetes
Peripheral Neuropathy
Pain
Lead sponsor: Washington University School of Medicine
Sponsor class: OTHER
First posted: 2015-02-16
Enrollment: 34
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: CROSSOVER
Primary purpose: TREATMENT

Brief summary: Diabetic nerve pain \[painful diabetic peripheral neuropathy\] is a common medical problem with few reliably effective treatments. There is some evidence that sensory testing may help determine how individuals will respond to analgesic therapy. In this study, the investigators are evaluating the relationship between sensory testing and subject response to lidocaine infusion therapy.

Detailed description: Diabetic peripheral neuropathy \[DPN\] is caused by diabetes-related metabolic damage to the sensory nervous system. It affects more than 3 million Americans and is leading cause of nerve damage-associated pain worldwide. Currently approved drugs such as gabapentin, pregabalin, and duloxetine provide pain relief only in 1 out of 4 or 5 people with DPN, pointing to a great need to identify effective therapy for these patients. Recent literature suggests that certain methods of assessing sensory nerve function in neuropathic pain patients may provide prediction to individual analgesic response; however, no placebo-controlled studies have been performed with the primary goal of identifying treatment response predictors in DPN.

We propose in this study to examine whether sensory testing to determine mechanical pain threshold \[MPT\] or heat pain threshold \[HPT\] will predict the subject's response to IV lidocaine analgesic therapy. We hypothesize that people with painful DPN who have high MPT or HPT are more likely to respond to lidocaine treatment. This is a prospective, double blind, placebo-controlled study with the primary objective of determining whether the results from the sensory testing predict the response to systemic lidocaine in patients with painful DPN.

Consented subjects will attend a screening visit and two intervention visits, during which they will undergo sensory testing and receive intravenous lidocaine or placebo infusion in a cross-over design. At enrollment, each patient will be assigned a study number, which will match a previously prepared computer-generated list of randomization numbers to determine the sequence of interventions: lidocaine and then placebo, or vice versa. An unblinded research nurse coordinator will be assigned to match the study number with randomized treatment sequence, and this person will prepare the study medications, which will look identical. This research nurse coordinator will not be involved at any stage at patient assessment or data analysis. The participants and all other study personnel will be blinded to the treatment allocation.

Eligibility criteria: Inclusion Criteria:

1. Age ≥18;
2. Diagnosis of Diabetes Mellitus (Fasting Plasma Glucose \> 126 mg/dL and/or HbA1C \>6.5%);
3. Distal symmetric pain in lower extremities with duration of more than 3 months;
4. Presence of either numbness or at least 1 sensory disturbance (increased or decreased sensitivity) in the feet.
5. Spontaneous pain with intensity of ≥ 4 on 0-10 Numerical Rating Scale (NRS).

Exclusion Criteria:

1. Not giving consent to participate in the study;
2. Unable to complete self-report pain questionnaire;
3. History of moderate to severe renal or liver failure;
4. History of other central or peripheral neurologic disorders;
5. History of cardiac arrhythmias;
6. Contraindication to intravenous lidocaine;
7. Pregnancy or lactation.

Primary outcomes:
measure: Change in Spontaneous Pain at 60-120 Minutes After Lidocaine Infusion Initiated (Assessed on 0-10 NRS)
timeFrame: Baseline compared to 60-120 minutes after starting the infusion
Secondary outcomes:
measure: Evoked Mechanical and Thermal Sensation at Baseline and 60 Minutes After Infusion Initiation.
timeFrame: - 60 minutes (baseline) and + 60 minutes of initiating infusion
measure: NPSI (Neuropathic Pain Symptom Inventory) Descriptors of Pain at Baseline and 60 Min After Infusion
timeFrame: Baseline to 60 minutes of initiating infusion
measure: Change in Spontaneous Pain Intensity as a Function of Baseline MPT
timeFrame: baseline to 60-120 minutes after starting the infusion
measure: Change in Spontaneous Pain Intensity as a Function of Baseline HPT
timeFrame: Baseline to 60-120 minutes after starting the infusion
Other outcomes:
Locations:
city: Saint Louis
country: United States
facility: Washington University School of Medicine/Barnes Jewish Hospital
state: Missouri
Study officials:
affiliation: Department of Anesthesiology, WUSTL
name: Simon Haroutounian, PhD
role: PRINCIPAL_INVESTIGATOR
References: