QST-Pupillometry in Sickle Cell Disease Patients

Study Overview
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Brief Summary
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There has been little progress for effective treatment of pain in sickle cell disease (SCD) patients. Many organizations have recognized that understanding the causes and reducing the burden of pain in SCD is critical in order to improve the quality of life in SCD patients. As patients with SCD face the challenge of living with both acute and chronic pain which is often improperly treated, our translational and interdisciplinary project aims to identify objective measures of pain sensitivity and its biochemical and genetic correlates. We hypothesize that SCD patients will have decreased tolerance to thermal and electrical stimuli.

Official Title
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Quantitative Sensory Testing and Pupillometry in Sickle Cell Disease Patients.

Conditions
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SCD With Severe Phenotype (HbSS, HbSβ0 Thalassemia, HbSOARab)

Intervention / Treatment
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* Other: Quantitative sensory testing


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: SCD with severe phenotype (HbSS, HbSbeta0 thalassemia, HbSOArab) Relatives of SCD patients who do not have sickle cell trait or SCD; healthy controls Exclusion Criteria: Completed overt clinical stroke or transient ischemic attack; Known severe vasculopathy or Moyamoya disease on brain MRA (Magnetic Resonance Angiography). history of having consumed alcohol within the last 12 hours prior to testing.

Ages Eligible for Study
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Minimum Age: 13 Years
Maximum Age: 30 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| High frequency pain group<br>39 pediatric or adult patients with high pain frequency (greater than or equal to 3 ER visits and/or hospitalizations for pain per year over the last two years) | Other: Quantitative sensory testing<br> <br> |
| Low Pain Frequency group<br>39 pediatric or adult patients with low pain frequency (less than or equal to 1 severe pain episode for the last two years) | Other: Quantitative sensory testing<br> <br> |
| Healthy control group<br>39 pediatric or adult relatives of sickle cell disease patients, who do not have the sickle cell trait of SCD. | Other: Quantitative sensory testing<br> <br> |
| Pain Crisis group<br>30 patients with sickle cell disease with severe phenotype (HbSS, HbSβ0 thalassemia, HbSOArab) | Other: Quantitative sensory testing<br> <br> |
| Pain Service group<br>10 patients without sickle cell disease admitted to the pain service. | Other: Quantitative sensory testing<br> <br> |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Measuring thermal responsiveness (perception and tolerance) in the outpatient groups. | Using a TSA (thermal sensory analyzer), the patients hot and cold perception and tolerance will be measured in the outpatient groups (high-pain and low-pain frequency and controls). | change between baseline and at 90day follow-up | 
| Measuring thermal responsiveness (perception and tolerance) in the inpatient groups. | Using a TSA thermal sensory analyzer, the patients hot and cold perception and tolerance will be measured in the inpatient groups (pain crisis and pain service). | change over 8 consecutive days | 
| Measure mechanical responsiveness in outpatient groups. | Using the Wagner PPIX 50 Pressure device, patient's tolerance to pressure is assessed in the outpatient groups (high-pain and low-pain frequency and controls). | change between baseline and 90 day follow-up | 
| Measure mechanical responsiveness in inpatient groups. | Using the Wagner PPIX 50 Pressure device, patient's tolerance to pressure is assessed in the inpatient groups (pain crisis and pain service). | change over 8 consecutive days | 
| Measuring the pupil responsiveness in outpatient groups. | Using the Pupillometer device, pupil responses are assessed in the outpatient groups (high-pain and low-pain frequency and controls). | change between baseline and 90 day follow-up | 
| Measuring the pupil responsiveness in inpatient groups. | Using the Pupillometer device, pupil responses are assessed in the inpatient groups (pain service and pain crisis). | change over 8 consecutive days | 
| Measuring electrical sensitivity in outpatient groups. | Using the Neurometer device, to assess electrical sensory perception and tolerance in the outpatient groups (high-pain and low-pain frequency and control). | change between baseline and at 90day follow-up | 
| Measuring electrical sensitivity in inpatient groups. | Using the Neurometer device, to assess electrical sensory perception and tolerance in the outpatient groups (pain service and pain crisis). | change over 8 consecutive days |