Duloxetine for LBP

Study Overview
=================
Brief Summary
-----------------
This research study will help determine whether a medication called duloxetine can improve back pain. It is well documented that many participants who come to the ER with acute low back pain still have low back pain 3 months later. The investigator team will attempt to determine whether duloxetine can help prevent this.

Detailed Description
-----------------
Participants will be eligible to take duloxetine/placebo if insufficient relief of pain after using naproxen for 48 hours has been reported.

Official Title
-----------------
Duloxetine for Patients With Low Back Pain Who Fail to Improve With Oral NSAIDs. A Randomized Placebo-controlled Exploratory Study

Conditions
-----------------
Back Pain, Low

Intervention / Treatment
-----------------
* Drug: Naproxen
* Drug: Duloxetine


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Present to Emergency Department (ED) primary for management of LBP, defined as pain originating between the lower border of the scapulae and the upper gluteal folds. Flank pain, that is pain originating from tissues lateral to the paraspinal muscles, will not be included. Musculoskeletal etiology of low back. Patients with non-musculoskeletal etiologies such as urinary tract infection, ovarian cysts, or influenza like illness will be excluded. The primary clinical diagnosis, at the conclusion of the ED visit, must be a diagnosis consistent with non-traumatic, non-radicular, musculoskeletal LBP. Patient is to be discharged home. Patients admitted to the hospital are more likely to be treated with parenteral medication and therefore are not appropriate for this study. Age 18-64 Enrollment will be limited to adults younger than 65 years because of the increased risk of adverse medication effects in older patients. Non-radicular pain. Patients will be excluded if the pain radiates below the gluteal folds in a radicular pattern. Pain duration <2 weeks (336 hours). Prior to the acute attack of LBP, back pain cannot occur more frequently than once per week. Functionally impairing back pain: A baseline score of > 5 on the Roland-Morris Disability Questionnaire Exclusion Criteria: Not available for follow-up Pregnant or breast-feeding Chronic pain syndrome defined as moderate or severe pain anywhere in their body on >50% of days for at least three months Allergic to or intolerant of investigational medications Contra-indications to non-steroidal anti-inflammatory drugs: history of hypersensitivity to NSAIDs or aspirin active or history of peptic ulcer disease, chronic dyspepsia, or active or history of gastrointestinal bleed Severe heart failure (NYHA 2 or worse) uncontrolled blood pressure (>160/100) Glomerular Filtration Rate (GFR_ <60ml/min Current use of anti-coagulants cirrhosis or acute hepatitis Contra-indication to duloxetine: alcohol use disorder chronic liver disease chronic kidney disease glaucoma Active use of medication for depression Score >4 on the Patient Health Questionnaire (PHQ-9) screening instrument or thoughts of suicide

Ages Eligible for Study
-----------------
Minimum Age: 18 Years
Maximum Age: 64 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Naproxen + duloxetine<br> | Drug: Naproxen<br>* Naproxen 500mg twice daily for 16 days<br>Drug: Duloxetine<br>* Duloxetine 60mg daily for 14 days<br>|
| Placebo Comparator: Naproxen + placebo<br> | Drug: Naproxen<br>* Naproxen 500mg twice daily for 16 days<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Number of participants with Moderate or severe pain | An ordinal pain scale (severe, moderate, mild, or none) will be used. Study participants will be asked to describe their worst back pain in the previous week. | 6 weeks | 
| Number of participants with Moderate or severe pain | An ordinal pain scale (severe, moderate, mild, or none) will be used. Study participants will be asked to describe their worst back pain in the previous 24 hours. | 16 days | 
| Number of participants with Moderate or severe pain | An ordinal pain scale (severe, moderate, mild, or none) will be used. Study participants will be asked to describe their worst back pain in the previous week. | 3 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Number of Participants demonstrating improvement based on Roland Morris Disability Questionnaire results | This 24-item lower back pain (LBP) functional scale is recommended for use in LBP research. Items are scored 0 if left blank or 1 if endorsed, for a total Roland Morris score ranging from 0-24. Higher scores represent higher levels of pain-related disability. | 6 weeks |