Prevalence of HIV-associated Neurocognitive Disorders (HAND) in a School of Medicine HIV/AIDS Outpatient Clinic
Condition: HIV-ASSOCIATED NEUROCOGNITIVE DISORDER (HAND)
MeSH terms: Neurocognitive Disorders
Study type: Observational

Summary: 
      1. To determine, in the Quillen College of Medicine HIV+ outpatient clinic, the prevalence
           of

             -  NC (normal cognition )

             -  ANI (asymptomatic neurocognitive impairment )

             -  MCD (mild cognitive disorder )

             -  HAD (HIV-associated dementia )

        2. To determine whether the following variables affect the three categories of HAND

             -  Time since first diagnosis of HIV infection

             -  Anti-viral medications used

             -  Age

             -  Gender
    

Detailed description: 
      As life expectancy increases, dementia becomes more common, and the need for its correct
      diagnosis and treatment becomes more urgent. Alzheimer's disease (AD) is the leading cause of
      dementia, but its diagnosis is by exclusion of all other causes. Successful treatment of
      HIV/AIDS has resulted in more patients living long enough to develop HIV-Associated
      Neurocognitive Disorders (HAND), including dementia.

      The National Institute of Mental Health, and the National Institute of Neurological Diseases
      and Stroke, updated standards for diagnosing HAND. The new criteria created an additional
      category, HIV-associated asymptomatic neurocognitive impairment (ANI), and modified the name
      and criteria for what was called MCMD (minor cognitive/motor disorder) to mild cognitive
      disorder (MCD). HIV-associated dementia (HAD) remained unchanged. Their definition of HAND
      includes: Cognitive impairment must be attributable to HIV and no other etiology (Dementia,
      Delirium, Depression, CNS neoplasm, CNS infection other than HIV/AIDS. Cerebrovascular
      disease, Substance abuse). Their criteria state that cognitive impairment should be validated
      by neuropsychological testing.

      The three categories of HAND are:

        1. HIV-associated asymptomatic neurocognitive impairment (ANI)

           Impairment involves at least two cognitive domains, and results in neuropsychological
           testing performance at least 1 Standard Deviation (SD) below the appropriate mean
           age/education norm for:

             -  Information processing speed

             -  Sensory/motor skills

             -  Short-term and long-term memory

             -  Ability to learn new skills and solve problems

             -  Attention, concentration, and distractibility

             -  Logical and abstract reasoning functions

             -  Ability to understand and express language

             -  Visual-spatial organization Visual-motor coordination

             -  Planning, synthesizing and organizing abilities

        2. Mild Cognitive Disorder (MCD) Same as ANI but patient or caregivers report that
           cognitive deficit interferes with mental acuity, work efficiency, home making or social
           activity

        3. HIV-associated dementia (HAD)

           Impairment involves at least two cognitive domains and results in neuropsychological
           testing at least 2 SD below the appropriate mean age/education norm for:

             -  Information processing speed

             -  Short-term and long-term memory

             -  Ability to learn new skills and solve problems

             -  Attention, concentration, and distractibility

             -  Logical and abstract reasoning functions

             -  Ability to understand and express language

             -  Visual-spatial organization Visual-motor coordination

             -  Planning, synthesizing and organizing abilities Cognitive impairment significantly
                interferes with work, home life, social activities or ADL's.

        4. Non-HIV healthy Controls

      Our P300 COGNISION apparatus, provided by Neuronetrix, has been used only in subjects over
      the age of 60, whereas our participants in the HAND study will all be younger than 60. So, we
      cannot use COGNISION normative data base for comparison. We will add 10 HIV- healthy controls
      to our planned 40 HIV+ subjects. These HIV- participants will be age- and gender-matched to
      the HIV- Asymptomatic Neurocognitive Impairment (ANI) patients, and will undergo all the same
      assessments

      Our IRB-approved study of HAND is limited to neuropsychological assessment. The study could
      be improved by adding a biological marker assessment, which could help validate the HAND
      categories. Such a marker is the P300 event-related potential (ERP), known to be related to
      cognitive processes, such as attention and working memory and abnormal in most neurologic and
      mental disorders. It could also possibly detect vulnerability to later cognitive impairment
      in those determined to be of normal cognition by neuropsychological testing. For example,
      Olichney et al (2011) concluded that ERP studies of individuals at risk for AD may reveal
      neurophysiological changes prior to clinical deficits, which could advance the early
      detection and diagnosis of "pre-symptomatic AD". Another example of the association of the
      P300 and cognition was the study of Onofri et al (2003). In this study donepezil resulted in
      improved cognition, as measured by a significant increase in MMSE scores. This was
      accompanied by a reduction of P3 latency. Logistic analysis showed that P3 latency predicted
      the beneficial effect of donepezil.
    

Observational model: Case-Control
Time perspective: Cross-Sectional
Sampling method: Probability Sample
Study population: 
        HIV+ individuals and Healthy controls (HIV-, age and gender matched)
      
Keywords: HIV; Dementia; HAND; COGNISION System; ERP; event-related potentials