Signs of mild-to-moderate neurocognitive impairment are often subtle and require questioning to determine if they are present.
The European AIDS Clinical Society (EACS) recommend1 that all HIV-infected people without any highly confounding conditions (severe psychiatric conditions, use of psychotropic drugs, alcohol abuse, sequelae from previous opportunistic infections of the CNS or a current CNS infection) should be screened using three questions on comprehension, clarity and speed every 2 years.
ANI=Asymptomatic Neurocognitive Impairment
GDR=genotypic drug resistance test
HAND=HIV-Associated Neurocognitive Disorder
IADL=Instrumental Activities of Daily Living
MND=Mild Neurocognitive Disorders
MRI=Brain Magnetic Resonance Imaging
i Highly confounding conditions 1. Severe psychiatric conditions; 2. Abuse of psychotropic drugs; 3. Alcohol abuse; 4. Sequelae from previous CNS-OIs or other neurological diseases; 5. Current CNS-OIs or other neurological diseases. ii 3 questions (ref. Simioni et al., AIDS 2009). 1. Do you experience frequent memory loss (e.g. do you forget the occurrence of special events even the more recent ones, appointments, etc.)? 2. Do you feel that you are slower when reasoning, planning activities, or solving problems? 3. Do you have difficulties paying attention (e.g. to a conversation, a book, or a movie)? For each question, patients can answer: a) never, b) hardly ever, or c) yes, definitely. Patients are considered to have an “abnormal” result when answering “yes, definitely” on at least one question. iii NP examination will have to include tests exploring the following cognitive domains: fluency, executive functions, speed of information processing, attention/working memory, verbal and visual learning, verbal and visual memory, motor skills (ref. Antinori et al., Neurology 2007). iv Brain MRI and CSF examination. These are required to further exclude other pathologies and to further characterize HAND, by including assessment of CSF HIV-RNA level and, where appropriate, evidence for genotypic drug resistance (GDR) in a paired CSF and plasma sample. v HAD and MND definitions (ref. Antinori et al., Neurology 2007). HAD is defined in the presence of 1) marked acquired impairment in cognitive functioning involving at least 2 cognitive domains, as documented by performance of at least 2 SD below the mean for age-education appropriate norms on NP tests; 2) marked interference in daily functioning; 3) no evidence of another pre-existing cause for the dementia. MND is defined in the presence of 1) acquired impairment in cognitive functioning involving at least 2 cognitive domains, as documented by performance of at least 1 SD below the mean for age-education appropriate norms on NP tests; 2) mild interference in daily functioning; 3) no evidence of another preexisting cause for the MND. vi If GDR in CSF and/or plasma not available, store aliquots for possible future use . vii Definition of ‘potentially CNS-active’ drugs: ARV drugs with either demonstrated clear CSF penetration when studied in healthy HIV-infected populations (concentration above the IC90 in > 90 % examined patients) or with proven short-term (3-6 months) efficacy on cognitive function or CSF viral load decay when evaluated as single agents or in controlled studies in peer reviewed papers:
- Agents with demonstrated clear CSF penetration:
- NRTIs: ZDV, ABC
- NNRTIs: EFV, NVP
- Boosted PIs: IND/r, LPV/r, DRV/r
- Other classes: MAR
- Drugs with proven “efficacy”:
- NRTIs: ZDV, d4T, ABC
- Boosted PIs: LPV/r
Reproduced with permission from the European AIDS Clinical Society Guidelines Version 6.0.
The International HIV Dementia Scale2 as a screening tool for neurocognitive impairment:
The recently developed Cysique algorithm3,4 has shown some success as a screening tool for HAND, with good prediction accuracy and specificity:
Mental health screening: A quick reference guide for HIV primary care clinicians contains questions to identify mental health disorders associated with HIV infection, including cognitive impairment.5
Find out more about neuropsychological assessment tools and tests, or refer to the signs and symptoms section for information on the misdiagnosis of HIV-associated dementia (HAD).
Please see below for other neuropsychological assessment tools and tests: