A brief and feasible paper-based method to screen for neurocognitive impairment in HIV-infected patients: the NEU screen

Screening Accuracy of Mini Addenbrooke's Cognitive Examination Test for HIV-Associated Neurocognitive Disorders in People Ageing with HIV

Aging and increased cardiovascular risk are major drivers for HIV-associated neurocognitive disorders (HAND), for which accurate screenings are lacking. Mini-Addenbrooke's Cognitive Examination (MACE) reliably detects vascular and neurodegenerative cognitive decline among HIV-negative patients. We evaluated MACE diagnostic accuracy in detecting HAND in people living with HIV (PLWH) and we compared it with the International HIV Dementia Scale (IHDS). A single-centre double-blind study of diagnostic accuracy on adult outpatient PLWH without neurocognitive confounding was performed. MACE and IHDS were administered in 5 and 10 min by clinicians, followed by the reference standard battery (14 tests) by neuropsychologists. HAND diagnosis was based on the modified version of Frascati's criteria by Gisslén to reduce false positives. Exploratory cut-offs were evaluated for MACE. Diagnostic accuracy and clinical utility parameters were assessed. 231 patients were enrolled. 75.7% men with a median age, education, and length of infection of 54 (48-59), 10 (8-13) and 16 (5-25) years. HAND prevalence was 48.5% (38.9% asymptomatic impairment). Compared to IHDS, MACE sensitivity (89.3% vs 70.5%), specificity (94.1% vs 63.0%), correct classification rate (86.5% vs 66.7%), J index (0.83 vs 0.34), AUROC (0.97 vs 0.79), agreement with the gold standard (k 0.84 vs 0.33) and effect size in distinguishing HAND vs non-HAND (d 2.11 vs 1.15) were higher. Among PLWH aged 65 years and above (n = 37) MACE performance was consistently better than IHDS. The quick and easy-to-perform MACE could possess an accurate and useful screening performance for HAND in otherwise neurocognitively healthy cohorts of PLWH.

Screening for HIV-Associated Neurocognitive Disorders: Sensitivity and Specificity

HIV-associated neurocognitive disorder (HAND) remains prevalent among people living with HIV (PLWH), especially the mild forms, even those with well-controlled HIV. Recommendations from the literature suggest routine and regular screening for HAND to detect it early and manage it effectively and adjust treatments, if warranted, when present. However, screening for HAND is not routinely done, as there are no current guidelines on when to screen and which test or tests to use. Furthermore, many of the available screening tools for HAND often cannot accurately detect the mild forms of HAND and require highly trained healthcare professionals to administer and score the tests, a requirement that is not feasible for those low- and middle-income countries with the highest HIV incidence and prevalence rates. The purpose of this chapter was to review recent research on screening tests to detect HAND and report on the strengths, limitations, and psychometric properties of those tests to detect HAND.

Assessment of executive functions as a measure of impairments in everyday functioning in persons with HIV

Persons with HIV can often present cognitive disorders such as those related to executive functioning, which could affect the daily life activities. The present study was designed to explore the predictive relationship between executive functions according to Miyake's model and the basic and instrumental skills of everyday functioning in a group of persons with HIV (PWH). Participants were recruited from outpatient treatment Hospital and assessed using a neuropsychological battery, a modified version of the Lawton and Brody basic and instrumental activities of daily life (ADL) scale and the Hospital Anxiety and Depression Scale (HADS). The results showed a low score in the executive function and significant relationship between executive functioning and the instrumental skills of the patients, with set-shifting being one of the most powerful predictors. The processes of executive functioning, particularly set-shifting, are related to the level of functioning in the skills required for independent living in the community, but not the skills of independent living in the home. This study seems to suggest the utility of assessing executive functions as a preventive measure for the development of dependencies in normal daily instrumental skills and as the focus of interdisciplinary interventions.

The Role of Mental Health Conditions in the Diagnosis of Neurocognitive Impairment in People Living with HIV

The aims of the present study were to evaluate the prevalence of undiagnosed mental health conditions (UMHC) in people living with HIV (PLWHIV) on antiretroviral treatment and with long-term suppressed HIV viremia, and its association with neurocognitive impairment (NCI). A cross-sectional observational study on HIV subjects, ≥18 years old, on stable antiretroviral treatment and with HIV viral load <50 copies/mL was carried out. Patients with known comorbidities, substances abuse, anxiety or depression were excluded. UMHC were evaluated by the Millon Clinical Multiaxial Inventory-III and NCI by Frascati criteria. The association between NCI and sociodemographic, clinical HIV variables and mental health conditions was analyzed. Further, the relationship between mental health conditions scores and NCI diagnosis was evaluated. Eighty patients were included, 37.5% had at least one undiagnosed mental health condition, and 26.3% had NCI. The most frequent mental health conditions were: anxiety (21.3%); bipolar disorder (11.3%); and substance dependence (8.8%). Only longer time since HIV diagnosis (p = 0.030) and at least one mental health condition diagnosis (p = 0.002) showed an association with NCI. Participants with NCI presented higher scores in anxiety, alcohol dependence and post-traumatic stress. Undiagnosed mental health conditions are frequent in PLWHIV. These disorders cannot be identified by HIV clinicians or basic screening questionnaires, and they are not usually self-reported by patients. UMHC could act as confounders in the evaluation of NCI.

NEU Screen Shows High Accuracy in Detecting Cognitive Impairment in Older Persons Living With HIV

The NEUrocognitive (NEU) Screen is a practical tool proposed to screen for HIV-associated cognitive impairment in the clinical setting. This is a pencil-and-paper method that can be applied rapidly (≤10 minutes for administration) and has no copyright limitations. In this study, we aimed at investigating its diagnostic accuracy in an older population of persons living with HIV (PLWH), with cutoffs set at 30, 40, 50, and 60 years. Data were collected from a sample of 368 PLWH who underwent a comprehensive neuropsychological tests battery (gold standard). Results of statistical tests showed that accuracy of the NEU Screen increased with age of the participants. The highest degree of precision, with a sensitivity of 91% and specificity of 92%, was obtained for people ages 60 years or older (correct classification: 91%). These optimal results point to the great potential of the NEU Screen as a tool for detecting cognitive disorders in older PLWH.

Neurocognitive Impairment in Well-Controlled HIV-Infected Patients: A Cross-Sectional Study

The reported prevalence of HIV-associated neurocognitive disorders in HIV people depends on the population studied and the methodology used. We analyze the prevalence of neurocognitive impairment (NCI) and associated factors in patients on successful antiretroviral therapy (ART), without comorbidities. Cross-sectional observational study in HIV subjects, ≥18 years old, on stable ART, and HIV viral load of <50 copies/mL. Patients with medical or psychiatric comorbidities and substance abuse were excluded. NCI was diagnosed using Frascati criteria, examining seven neurocognitive domains (NDs). We analyzed the association between NCI and HIV-related clinical variables, carotid intima-media thickness, bacterial translocation, and plasma inflammatory biomarkers [soluble CD14, interleukin-6 (IL-6), and tumor necrosis factor-α]. The prevalence of NCI was calculated with a 95% confidence interval (CI). We fitted a logistic regression model to assess the strength of the associations. Eighty-four patients were included with an observed NCI prevalence of 29.8% (95% CI: 21.0-40.2): 19% had asymptomatic NCI, 8.3% had mild neurocognitive disorder, and 2.4% had HIV-associated dementia. Delayed recall was the most commonly affected ND (27.4%). People diagnosed at least 10 years ago (odds ratio [OR]: 6.5, 95% CI: 1.6-21.7) and those with IL-6 levels above 1.8 pg/mL (OR: 6.0, 95% CI: 1.1-31.3) showed higher odds of NCI in adjusted analyses. Participants with carotid plaques had lower scores for delayed recall: -0.9 ± 1.1 versus -0.2 ± 1.1 (p = .04). Prevalence of NCI is high in otherwise healthy adults with HIV-infection. In this population, more than 10 years since HIV diagnosis and high IL-6 levels are associated with NCI. Delayed recall ND is worse in patients with subclinical atherosclerosis.

Objective memory as an indicator of functional impairment in native Spanish-speaking patients with HIV infection

Objective memory is one of the most affected cognitive areas in patients with HIV and perhaps one of the best predictors of daily functioning problems. Its relationship with biological markers, mood symptoms, and cognitive complaint is unclear and has received little attention in native Spanish-speakers. The goal of this study is to explore the relationships between the above-mentioned variables and their prediction of objective memory performance in native Spanish-speakers. HIV-related biological markers, mood symptoms, cognitive complaint, and objective memory were assessed in a sample native Spanish-speaking HIV patient with possible cognitive impairment. The results revealed deficit in short- and long-term memory while recognition was retained. Hierarchical regression analysis showed that the combination of independent variables significantly predicted performance in recognition, indicating that the pattern of impairment in short- and long-term memory is related to a difficulty to learn new information discriminately. The non-prediction of short- and long-term memory performance may be related to the inability to estimate the deficit in objective memory. These results show the need to perform specific interventions in mnesic processes, in view of the relation between this cognitive process and patients' daily functioning.

Properties of a brief assessment tool for longitudinal measurement of cognition in people living with HIV

Background

Mild cognitive impairment is common in chronic HIV infection and there is concern that it may worsen with age. Distinguishing static impairment from on-going decline is clinically important, but the field lacks well-validated cognitive measures sensitive to decline and feasible for routine clinical use. Measures capable of detecting improvement are also needed to assess interventions. The objective of this study is to estimate the extent of change on repeat administration of three different forms of a brief computerized cognitive assessment battery (B-CAM) developed for assessing cognitive ability in the mildly-impaired to normal range in people living with HIV. We hypothesized no change over a six-month period in people on effective antiretroviral therapy.

Methods

102 HIV+ individuals completed a set of computerized cognitive tasks on three occasions over a six-month period. Rasch analysis was used to determine if change over time (i.e. improvement due to practice) was uniform across tasks and to refine scoring in order to produce three forms of the B-CAM of equivalent level of difficulty. Group-based trajectory analysis (GBTA) was then applied to determine if performance at baseline influenced the magnitude of practice-related improvement on the battery as a whole over the course of follow-up.

Results

Two cognitive tasks (fluency and word recall) had different levels of difficulty across test sessions, related to the different forms of the tasks. These two items were split by testing session. For all other items, the level of difficulty remained constant across all three time points. GBTA showed that the sample was composed of three distinct groups of people with unique trajectories, defined mainly by level of cognitive ability at baseline. Only the highest group showed an apparent improvement over time, but this change fell within measurement error.

Conclusions

Rasch analysis provides mathematical confirmation that these three forms of the B-CAM are of equivalent difficulty. GBTA demonstrates that no adjustment of the total score is required to correct for practice effects. Application of these modern statistical methods paves the way towards rapid and robust quantification of change in cognition.

Diagnostic utility of the HIV dementia scale and the international HIV dementia scale in screening for HIV-associated neurocognitive disorders among Spanish-speaking adults

Given that neurocognitive impairment is a frequent complication of HIV-1 infection in Spanish-speaking adults, the limited number of studies assessing HIV-associated neurocognitive disorders (HAND) in this population raises serious clinical concern. In addition to being appropriately translated, instruments need to be modified, normed, and validated accordingly. The purpose of the current study was to examine the diagnostic utility of the HIV Dementia Scale (HDS) and International HIV Dementia Scale (IHDS) to screen for HAND in Spanish-speaking adults living with HIV infection. Participants were classified as either HAND (N = 47) or No-HAND (N = 53) after completing a comprehensive neuropsychological evaluation. Receiver operating characteristic analyses found the HDS (AUC = .706) was more sensitive to detecting HAND than the IHDS (AUC = .600). Optimal cutoff scores were 9.5 for the HDS (PPV = 65.2%, NPV = 71.4%) and 9.0 for the IHDS (PPV = 59.4%, NPV = 59.1%). Canonical Correlation Analysis found the HDS converged with attention and executive functioning. Findings suggest that while the IHDS may not be an appropriate screening instrument with this population, the HDS retains sufficient statistical validity and clinical utility to screen for HAND in Spanish-speaking adults as a time-efficient and cost-effective measure in clinical settings with limited resources.

Monitoring HIV-Associated Neurocognitive Disorder Using Screenings: a Critical Review Including Guidelines for Clinical and Research Use

Screening tools to identify HIV-associated neurocognitive disorder (HAND) are primarily devised to detect cognitive impairment on a single occasion. With the chronicity of HIV infection and the risk of HAND developing or progressing despite viral control, it may be pertinent to repeat HAND screening at more than one time point. Despite this, there are limited data on longitudinal use of such screening tools, particularly with regard to the role of practice effects. Additionally, no guidelines currently exist on the timeframe between testing intervals, or recommendation of the magnitude of baseline impairment that warrants follow-up testing. The aim of the current paper was to review existing evidence for longitudinal validity of HAND screening tools. Only those HAND screening tools previously found to have high cross-sectional criterion validity were included. Preliminary recommendations for clinical use and future research are proposed including in international settings.

Self-Reported Decline in Everyday Function, Cognitive Symptoms, and Cognitive Function in People With HIV

BACKGROUND

We determined factors associated with self-reported decline in activities of daily living (ADLs) and symptoms of cognitive impairment in HIV positive adults in 5 European clinics.

METHODS

HIV+ adults underwent computerized and pen-and-paper neuropsychological tests and questionnaires of cognitive symptoms and ADLs. We considered cognitive function in 5 domains, psychosocial factors, and clinical parameters as potentially associated with symptoms. Separate regression analyses were used to determine factors associated with a decline in ADL (defined as self-reported decline affecting ≥2 ADLs and attributed to cognitive difficulties) and self-reported frequency of symptoms of cognitive impairment. We also estimated the diagnostic accuracy of both questionnaires as tests for cognitive impairment.

RESULTS

Four hundred forty-eight patients completed the assessments [mean age 45.8 years, 84% male, 87% white, median CD4 count 550 cells/mm, median time since HIV diagnosis 9.9 years, 81% virologically suppressed (HIV-1 plasma RNA <50 copies/mL)]. Ninety-six (21.4%) reported decline in ADLs and attributed this to cognitive difficulties. Self-reported decline in ADLs and increased symptoms of cognitive impairment were both associated with worse performance on some cognitive tests. There were also strong associations with financial difficulties, depressive and anxiety symptoms, unemployment, and longer time since HIV diagnosis. Both questionnaires performed poorly as diagnostic tests for cognitive impairment.

CONCLUSIONS

Patients' own assessments of everyday function and symptoms were associated with objectively measured cognitive function. However, there were strong associations with other psychosocial issues including mood and anxiety disorders and socioeconomic hardship. This should be considered when assessing HIV-associated cognitive impairment in clinical care or research studies.

Transdermal rivastigmine for HIV-associated cognitive impairment: A randomized pilot study

Objective

To assess the efficacy and safety of transdermal rivastigmine for the treatment of HIV-associated cognitive impairment.

Methods

We recruited HIV-infected patients with cognitive impairment on stable antiretroviral therapy in a randomized controlled pilot trial with a 48-week follow-up. An additional assessment was held at 12 weeks. Participants received transdermal rivastigmine (9.5 mg daily), lithium (400 mg twice daily, titrated progressively), or remained in a control group (no new medication). The primary efficacy endpoint was change in a global cognitive score (NPZ-7). Secondary endpoints included change in specific cognitive measures, domains, and functional parameters. Safety covered the frequency of adverse events and changes in laboratory results.

Results

Seventy-six subjects were screened, and 29 were finally enrolled. Better cognitive outcomes were observed in all groups, although there were no significant differences between the arms (mean NPZ-7 change [SD]): rivastigmine, 0.35 (0.14); lithium, 0.25 (0.40); control, 0.20 (0.44) (p = 0.78). The rivastigmine group showed the highest positive trend (mean NPZ-7 [SD], baseline vs week 48): rivastigmine, –0.47 (0.22) vs –0.11 (0.29), p = 0.06; lithium, –0.50 (0.40) vs –0.26 (0.21), p = 0.22; control, –0.52 (0.34) vs –0.32 (0.52), p = 0.44. The cognitive domains with the highest positive trends were information processing speed at week 12 and executive function at week 48 (rivastigmine vs control): information processing speed, 0.35 (0.64) vs –0.13 (0.25), p = 0.17, d = 0.96; and executive functioning, 0.73 (0.33) vs 0.03 (0.74), p = 0.09, d = 1.18. No relevant changes were observed regarding functional outcomes. A total of 12 (41%) individuals dropped out of the study: 2 (20%) were due to medication-related effects in the rivastigmine group and 4 (36%) in the lithium group. No severe adverse events were reported.

Conclusions

The results from this small randomized trial indicate that transdermal rivastigmine did not provide significant cognitive benefits in people with HAND on stable antiretroviral therapy, even though positive trends were found in specific cognitive domains. Relevant tolerability issues were not observed.

HIV-1-associated neurocognitive disorder: epidemiology, pathogenesis, diagnosis, and treatment

The modern antiretroviral treatment of human immunodeficiency virus (HIV-1) infection has considerably lowered the incidence of opportunistic infections. With the exception of the most severe dementia manifestations, the incidence and prevalence of HIV-associated neurocognitive disorders (HAND) have not decreased, and HAND continues to be relevant in daily clinical practice. Now, HAND occurs in earlier stages of HIV infection, and the clinical course differs from that before the widespread use of combination antiretroviral treatment (cART). The predominant clinical feature is a subcortical dementia with deficits in the domains concentration, attention, and memory. Motor signs such as gait disturbance and impaired manual dexterity have become less prominent. Prior to the advent of cART, the cerebral dysfunction could at least partially be explained by the viral load and by virus-associated histopathological findings. In subjects where cART has led to undetectable or at least very low viral load, the pathogenic virus-brain interaction is less direct, and an array of poorly understood immunological and probably toxic phenomena are discussed. This paper gives an overview of the current concepts in the field of HAND and provides suggestions for the diagnostic and therapeutic management.

Adding a brief self-report cognitive tool to the IHDS improves effectiveness of identifying patients with HIV-associated dementia in South Africa

We compared the diagnostic accuracy of two brief screening tools (the International HIV Dementia Scale (IHDS), and the IHDS combined with a novel self-report instrument, the HIV Cognitive Symptom Questionnaire (HCSQ)) with that of three brief neuropsychological screening batteries (a 2-, a 3-, and a 4-test battery, each consisting of standardized cognitive tests) in discriminating individuals with HIV-associated dementia (HAD) from those with milder forms of cognitive impairment. We analyzed data from 94 isiXhosa-speaking South African HIV-infected participants who were screened as part of a clinical trial evaluating adjunctive treatment in patients with moderate to severe HIV-associated cognitive impairment. A comprehensive neuropsychological battery diagnosed 53% (50/94) of the participants with HAD. We evaluated the sensitivity and specificity for the screening tools and screening batteries. The brief screening tool performed better compared to the brief neuropsychology battery. The IHDS-HCSQ combination delivered 94% sensitivity and 63% specificity for HAD compared to the IHDS (74 and 70% at a cutoff of ≤8) which offers a viable and quick way to screen for HAD in people living with HIV. It is easy to administer, is time- and cost-efficient, and it appears to be a better option, for these purposes, than brief neuropsychology batteries. It is viable for use in clinical, research, and workplace settings when identification of HIV-infected people with severe cognitive impairment is required.

Validation of the International HIV Dementia Scale as a Screening Tool for HIV-Associated Neurocognitive Disorders in a German-Speaking HIV Outpatient Clinic

Background

HIV-associated neurocognitive disorders (HAND) are widely present among people living with HIV. Especially its milder forms, asymptomatic neurocognitive impairment (ANI) and mild neurocognitive disorder (MND), remain highly prevalent worldwide. Diagnosing these conditions is subject to a time and resource consuming neuropsychological assessment. Selecting patients at a higher risk of cognitive impairment by using a simple but effective screening tool helps to organise access to further neuropsychological diagnosis. The International HIV Dementia Scale (IHDS) has until now been a well-established screening tool in African and American countries, however these populations’ demographics defer significantly from ours, so using the same parameters could be ineffective.

Objectives

To calculate the prevalence of this condition among people attending an HIV outpatient clinic in Berlin and to validate the use of the IHDS as a screening tool for HAND in a German-speaking population.

Methods

We screened 480 HIV-infected patients using the IHDS, 89% of them were on a stable antiretroviral treatment. Ninety of them completed a standardised neuropsychological battery of tests and a specific cognitive complaints questionnaire. The same procedure was applied to a control group of 30 HIV-negative participants. HAND diagnosis was established according to the Frascati criteria.

Results

The overall prevalence of HAND in our cohort was 43% (20% ANI, 17% MND and 6% HIV-associated dementia). The optimal cut-off on the IHDS for detecting HAND cases was set at 11 and achieved both a sensitivity and a specificity of 80%. When specifically screening for the more severe form of HAND, HIV-associated dementia, a cut-off value of 10 offered an increase in both sensitivity (94%) and specificity (86%). The Youden Index for diagnostic accuracy was 0.6 and 0.8, respectively.

Conclusions

The prevalence of HAND was comparable to the reported by recent studies performed in countries with a similar economic development. The study confirms the IHDS to be a useful HAND screening tool in primary care settings and establishes new recommendations for its use in German-speaking countries.

Neuropsychological screening tools in Italian HIV+ patients: a comparison of Montreal Cognitive Assessment (MoCA) and Mini Mental State Examination (MMSE)

OBJECTIVE

Despite the progress in HIV treatments, mild forms of cognitive impairment still persist. Brief and sensitive screening tools are needed. We evaluated the accuracy of the Montreal Cognitive Assessment (MoCA) compared to the Mini Mental State Examination (MMSE) to detect cognitive impairment in HIV-infected participants.

METHOD

HIV-infected patients were consecutively enrolled during routine outpatient visits at a single institution. The MoCA, the MMSE, and a comprehensive neuropsychological battery were administered. Patients were considered as affected by cognitive impairment if they showed decreased cognitive function in at least two ability domains based on age and education adjusted Italian normative cut-offs.

RESULTS

Ninety-three HIV-infected participants (75% males, median age 47, all on antiretroviral therapy; 90% HIV-RNA <50copies/mL, median CD4 644 cells/μL) were enrolled. Thirteen participants (14%) were diagnosed as cognitively compromised via a comprehensive neuropsychological examination. The area under the curve of the adjusted MMSE and MoCA scores to detect cognitive impairment were .51 (95% CI = .31-.72, p = .877) and .70 (95% CI = .53-.86, p = .025), respectively. A MoCA score <22 was able to predict the cognitive impairment with 62% of sensitivity and 76% of specificity.

CONCLUSIONS

Our findings suggested that the prognostic performance of the MoCA to detect cognitive impairment among mildly impaired HIV-infected participants was only moderate. Further investigations are needed to identify optimal cognitive tests to screen HIV-infected individuals or to explore whether a combination of cognitive tests might represent a viable alternative to a single screening tool.

Utility of the Montreal Cognitive Assessment (MoCA) and its subset in HIV-associated neurocognitive disorder (HAND) screening

OBJECTIVES

The Montreal Cognitive Assessment (MoCA) is a useful screening tool for mild cognitive impairment. We aimed to know whether the full MoCA and subsets of the full test are effective for detecting HIV-associated neurocognitive disorder (HAND).

METHODS

We examined the socio-demographic, clinical, functional, and neuropsychological levels of 194 HIV-infected patients. We compared total scores and scores from each cognitive domain of MoCA between patients with and without HAND. We also examined the utility of subsets of the full test using a few selective domains. The diagnostic accuracies of MoCA and subset composition were evaluated.

RESULTS

The total scores of MoCA (P<0.001) and scores from Trail Making Test-B (P=0.020), attention domain (P=0.005), and immediate (P=0.003) and delayed recall (P=0.002) differed between patients with and without HAND. A subset composed of Trail Making Test-B, rescored serial subtraction, and immediate/delayed recall showed a 69.2% accuracy.

CONCLUSIONS

Our results suggest that the MoCA and its subsets alone are not sufficient in screening for HAND. Further studies will be needed to develop a simpler and easier screening tool for HAND based on this study.

[HIV 1-associated neurocognitive disorder: current epidemiology, pathogenesis, diagnosis and management]

By restoring the immunological function the modern antiretroviral treatment of human immunodeficiency virus (HIV-1) infection has considerably lowered the incidence of opportunistic infections. As opposed to the classical manifestations of HIV-induced immunosuppression the incidence and prevalence of HIV-associated neurocognitive disorders (HAND) has not noticeably decreased and HAND continues to be relevant in daily clinical practice. At present, HAND occurs in earlier stages of HIV infection, and the clinical course differs from that before the introduction of combination antiretroviral treatment (cART). The predominant clinical manifestation is a subcortical dementia with deficits in the domains attention, concentration and memory. Signs of central motor pathway lesions have become less frequent and less prominent. Prior to the advent of cART the cerebral dysfunction could at least partially be explained by the viral load and by virus-associated histopathological findings. In patients with at least partially successfully treated infections, this relationship no longer exists, but a plethora of poorly understood immunological and probably toxic phenomena are under discussion.This consensus paper summarizes the progress made in the last 12 years in the field of HAND and provides suggestions for the diagnostic and therapeutic management.

Interactions between ageing and NeuroAIDS

PURPOSE OF REVIEW

The purpose of this study is to summarize recent advances in ageing and neuroAIDS by reviewing relevant articles from the preceding 18 months from PubMed and PsycINFO databases.

RECENT FINDINGS

The success of combination antiretroviral therapy (cART) has led to ageing of the HIV-infected population, which in turn contributes to the prevalence of HIV-associated neurocognitive disorder (HAND). Biomedical advances continue to clarify the pathophysiology of HAND despite effective cART, including chronic inflammatory and neurovascular causes. In recent months, associations between HAND and nonneurological medical diseases have been identified, as well as linkage to neuroimaging in those ageing with HIV. Developing effective screening tools to detect impairment remains an important scientific gap, although promoting factors associated with successful cognitive ageing is emerging as a possible means of enhancing quality of life.

SUMMARY

A greater understanding of HAND pathophysiology among treated individuals with suppressed virus will aid in explaining the high prevalence of HAND despite effective cART and allow for development of novel targeted interventions. Neuroimaging and other biomarkers show promise in discerning HAND from age-associated cognitive disorders. Effective screening tools remain critically needed. Together, this work will inform promising strategies needed to address issues pertinent to an expanding group of older patients living with HIV.

Cross-sectional study of unexplained white matter lesions in HIV positive individuals undergoing brain magnetic resonance imaging

White matter (WM) abnormalities are frequently seen on brain MRI of HIV positive (HIV+) patients. We aimed to determine the prevalence of unexplained WM abnormalities and their associations with HIV disease and cardiovascular risk factors. We conducted a retrospective, cross-sectional study of brain MRI of HIV+ patients conducted between 2004 and 2009 at our center. Clinical and laboratory data were compiled, and images were independently reviewed for WM lesions. Images were obtained from 254 patients: 70% male, 53% white, 40% black, mean age 42 years, median current CD4 count 240 cells/mm(3), and 41% not taking antiretroviral therapy (ART). Hyperintense WM lesions were present in 161 patients (63.4%): 89 scans (35.0%) showed diffuse WM signal abnormality (DWMSA), 61 (24.0%) were consistent with small vessel disease (SVD, graded by Fazekas' scale), and 37 (14.6%) showed large asymmetrical focal WM lesions. SVD changes were associated with age and cardiovascular risk factors, and while cerebral SVD may be related to HIV infection, the MRI findings were not associated with HIV-related factors. The only risk factor for DWMSA was black race, and no correlation with cardiovascular risk factors, CD4 count, or clinical presentation was identified. DWMSA are therefore of uncertain neurological significance in HIV+ patients and could represent more than one clinicopathological entity.

Clinical utility of the Wechsler Adult Intelligence Scale-Fourth Edition after traumatic brain injury

The performance of 100 patients with traumatic brain injury (TBI) on the Wechsler Adult Intelligence Scale-Fourth Edition (WAIS-IV) was compared with that of 100 demographically matched neurologically healthy controls. Processing Speed was the only WAIS-IV factor index that was able to discriminate between persons with moderate-severe TBI on the one hand and persons with either less severe TBI or neurologically healthy controls on the other hand. The Processing Speed index also had acceptable sensitivity and specificity when differentiating between patients with TBI who either did or did not have scores in the clinically significant range on the Trail Making Test. It is concluded that WAIS-IV Processing Speed has acceptable clinical utility in the evaluation of patients with moderate-severe TBI but that it should be supplemented with other measures to assure sufficient accuracy in the diagnostic process.

HIV-associated neurocognitive disorders

Currently, neuropsychological impairment among HIV+ patients on antiretroviral therapy leads to a reduction in the quality of life and it is an important challenge due to the high prevalence of HIV-associated neurocognitive disorders and its concomitant consequences in relation to morbidity and mortality- including those HIV+ patients with adequate immunological and virological status. The fact that the virus is established in CNS in the early stages and its persistence within the CNS can help us to understand HIV-related brain injury even when highly active antiretroviral therapy is effective. The rising interest in HIV associated neurocognitive disorders has let to development new diagnostic tools, improvement of the neuropsychological tests, and the use of new biomarkers and new neuroimaging techniques that can help the diagnosis. Standardization and homogenization of neurocognitive tests as well as normalizing and simplification of easily accessible tools that can identify patients with increased risk of cognitive impairment represent an urgent requirement. Future efforts should also focus on diagnostic keys and searching for useful strategies in order to decrease HIV neurotoxicity within the CNS.