Clinical Phenotyping and Genotyping of HIV-Associated Sensory Neuropathy: The HIV-POGO Study

Study Overview
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Brief Summary
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This study aims to recruit a cohort of HIV patients with and without HIV-SN and to identify genetic risk factors for the development of HIV-SN and neuropathic pain. It also aims to more deeply phenotype the condition, using well validated questionnaires, and to identify any influence that early neurocognitive dysfunction may have on the reporting, diagnosis and treatment of neuropathic pain in the HIV population.

Detailed Description
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HIV associated sensory neuropathy (HIV-SN) is a frequent complication of HIV infection, affecting between 20 and 57% of infected individuals. The advent of better antiretroviral treatment for HIV has meant that mortality from HIV has decreased dramatically in the UK. This means however, that chronic, age-related conditions associated with HIV, such as HIV-SN and cognitive impairment, are increasing in prevalence and becoming a significant disease burden. The classification, diagnosis and treatment of HIV-SN remains poor. Currently, little is known about the genetic basis of the disorder and what risk factors mean that some patients with HIV develop neuropathy and pain, whilst others do not. It is hoped that by further characterising or 'phenotyping' the disorder, it will be easier to identify which patients are at risk of developing neuropathy and chronic pain. It may also mean that treatment can be more individualised as currently patients often undergo a frustrating 'trial and error' protocol of treatment, as clinicians can not yet predict who will respond to which treatment. It has also been suggested that there is a link between HIV-SN and HIV associated neurocognitive disorder (HAND), which is another common, age-related complication of HIV infection. It may be that the existence of one pathology could predict the development of the other, or that the presence of HAND may impair the diagnosis or treatment of chronic pain associated with HIV-SN.

Official Title
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Clinical Phenotyping and Genotyping of HIV-Associated Sensory Neuropathy: The HIV-POGO Study

Conditions
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HIV, Sensory Neuropathy, Neuropathic Pain

Intervention / Treatment
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* Other: No Intervention


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Aged 18 years or over HIV infection Exclusion Criteria: co-incident severe neurological disease co-incident severe psychiatric illness limited english language skills so as not able to conduct quantitative sensory testing pregnancy pain of greater than 3/10 on an NRS due to pathology other than HIV-SN

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Intervention/Treatment |
| --- |
|Other: No Intervention|No intervention - observational only|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Neuropathic Element of Pain Using the Doleur Neuropathique 4 Interview | Doleur Neuropathique 4 Interview score greater than or equal to 4, indicating a high likelihood of neuropathic pain | Day 1 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Cognitive Function: Global T-score for Cogstate Computerised Cognitive Function Test Set | Cogstate computerised cognitive function testing. A global T-score is a composite measure determined by the arithmetric mean of 8 test scores covering the following cognitive domains: psychomotor function, visual learning, working memory, executive function, emotional recognition, verbal learning, attention and verbal memory. Raw scores were converted to a standardised T score using age adjusted normative data (mean 50; standard deviation 10). Higher scores are interpreted as 'better' cognitive function. | Day 1 | 
| Conditioned Pain Modulation Efficiency | Conditioned Pain Modulation (CPM) efficiency to protocol using a cold noxious stimulus. The CPM efficiency is calculated as the pressure pain threshold (measured with an algometer on the forearm) during the noxious conditioning stimulus minus the pressure pain threshold prior to conditioning stimulus. | Day 1 | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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HIV, Sensory Neuropathy