Timed Gait test: normative data for the assessment of the AIDS dementia complex

Neuropsychological Correlates of Adherence in Youth with Behaviorally Acquired HIV

Youth living with behaviorally acquired HIV (YLWH) are at-risk for both neuropsychological disorders and antiretroviral therapy (ART) non-adherence; little is known about their interrelationship over time in YLWH. Neuropsychological and psychiatric functioning, substance use, and self-report of 7-day/week and weekend ART adherence were assessed at baseline and Weeks 24, 48, 96 and 144 of a longitudinal study evaluating the impact of early (CD4>350) versus standard of care (CD4≤350) treatment initiation on neuropsychological functioning in 111 treatment-naïve YLWH age 18-24 years at entry. Bayesian multi-level models for adherence (≥ 90% vs. <90%) were fit using random intercepts for repeated measures. Adjusted odds ratios (OR [95% credible interval]) for higher versus lower baseline Motor function for visit adherence were 0.58 (0.25, 1.16), 0.5 (0.15, 1.38), 0.52 (0.16, 1.52), and 0.94 (0.3, 2.8) at Weeks 24, 48, 96, and 144, respectively. Week 24 adherence was associated with higher adjusted odds of Motor function at Week 48 (week: 0.27, -0.05-0.59; weekend: 0.28, -0.07-0.62). Week 96 Complex Executive functioning was associated with higher adjusted odds of adherence at Week 144, OR = 4.26 (1.50, 14.33). Higher Motor functioning emerged most consistently associated with lower odds of adherence in YLWH. Complex Executive functioning was associated with adherence only at end of study, suggesting potential contribution in adherence over the long-term.

Signatures of somatosensory cortical dysfunction in Alzheimer's disease and HIV-associated neurocognitive disorder

Alzheimer's disease is the most common type of dementia in the general population, while HIV-associated neurocognitive disorder is the most common neurological comorbidity in those infected with HIV and affects between 40 and 70% of this population. Both conditions are associated with cognitive impairment and have been associated with aberrant functioning in sensory cortices, but far less is known about their disparate effects on neural activity. Identifying such disparate effects is important because it may provide critical data on the similarities and differences in the neuropathology underlying cognitive decline in each condition. In the current study, we utilized magnetoencephalography, extensive neuropsychological testing and a paired-pulse somatosensory gating paradigm to probe differences in somatosensory processing in participants from two ongoing magnetoencephalography studies. The resulting participant groups included 27 cognitively normal controls, 26 participants with HIV-associated neurocognitive disorder and 21 amyloid biomarker-confirmed patients with Alzheimer's disease. The data were imaged using a beamformer and voxel time series were extracted to identify the oscillatory dynamics serving somatosensory processing, as well as the amplitude of spontaneous cortical activity preceding stimulation onset. Our findings indicated that people with Alzheimer's disease and HIV-associated neurocognitive disorder exhibit normal somatosensory gating but have distinct aberrations in other elements of somatosensory cortical function. Essentially, those with Alzheimer's disease exhibited accentuated neural responses to somatosensory stimulation, along with spontaneous gamma activity preceding stimulus onset. In contrast, those with HIV-associated neurocognitive disorder exhibited normal responses to somatosensory stimulation but had sharply elevated spontaneous gamma activity prior to stimulus onset. These distinct aberrations may reflect the impact of different neuropathological mechanisms underlying each condition. Further, given the differential pattern of deficits in somatosensory cortical function, these measures may function as unique biomarkers in each condition and be useful in identifying persons with HIV who may go on to develop Alzheimer's disease.

Neurocognitive outcomes of tuberculous meningitis in a primarily HIV-positive Ugandan cohort

Background: The toll of tuberculous meningitis (TBM) in both mortality and disability is considerable, but advancements in rehabilitation have the potential to improve the functional abilities and the quality of survivors' lives. However, the typical phenotype of neurocognitive impairment in TBM survivors remains unstudied in HIV-predominant populations in sub-Saharan Africa. Methods: We tested 36 survivors of TBM in Uganda with a comprehensive battery of neurocognitive assessments at 8 and 24 weeks after diagnosis, and compared results to a representative cohort of HIV-uninfected Ugandans. Results: While participants had a broad range of impairments at eight weeks, there was marked improvement by 24 weeks, when a phenotype of impairment including deficits in motor functioning, verbal learning and memory, processing speed, and executive function emerged. These deficits were present despite good clinician-rated functional status. The majority (23/27, 85%) had evidence of moderate to severe depression at week 8, and at week 24 (18/24, 75%). Conclusion: These findings highlight the need for more comprehensive neurocognitive assessment in the survivors of TBM, and further investment in and study of rehabilitation, including management of depression, to improve long-term outcomes in this population.

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.

Neurocognitive outcomes of HIV-associated tuberculous meningitis

Background: The toll of tuberculous meningitis (TBM) in both mortality and disability is considerable, but advancements in rehabilitation have the potential to improve the functional abilities and the quality of survivors' lives. However, the typical phenotype of neurocognitive impairment in TBM survivors remains unstudied in HIV-predominant populations in sub-Saharan Africa. Methods: We tested 36 survivors of TBM in Uganda with a comprehensive battery of neurocognitive assessments at 8 and 24 weeks after diagnosis, and compared results to a representative cohort of HIV-uninfected Ugandans. Results: While participants had a broad range of impairments at eight weeks, there was marked improvement by 24 weeks, when a phenotype of impairment including deficits in motor functioning, verbal learning and memory, processing speed, and executive function emerged. These deficits were present despite good clinician-rated functional status. The majority (23/27, 85%) had evidence of moderate to severe depression at week 8, and at week 24 (18/24, 75%). Conclusion: These findings highlight the need for more comprehensive neurocognitive assessment in the survivors of TBM, and further investment in and study of rehabilitation, including management of depression, to improve long-term outcomes in this population.

Trajectories of Depressive Symptoms, Neurocognitive Function, and Viral Suppression With Antiretroviral Therapy Among Youth With HIV Over 36 months

BACKGROUND

Depression and neurocognitive impairment are highly prevalent among persons living with HIV and associated with poorer clinical outcomes; however, longitudinal studies of depression-neurocognition relationships in youth living with HIV (YLWH), and the role of antiretroviral therapy (ART), are lacking. This study tested whether (1) depressive symptomatology, across somatic, cognitive, and affective symptom domains, improved with ART and (2) more severe depressive symptoms at baseline were associated with poorer neurocognitive function and poorer HIV suppression.

SETTING

Data were collected from 181 YLWH (18-24 years) who were treatment-naive, a subset of whom (n = 116) initiated ART.

METHODS

Participants were categorized into elevated (DS) or nonelevated (non-DS) depressive symptom groups at entry (Beck Depression Inventory-II ≥14) and followed for 36 months. Neurocognition (5-domain battery) and depressive symptoms were repeatedly assessed. Longitudinal models examined depressive symptomatology, neurocognition, and odds of HIV nonsuppression by group.

RESULTS

Greater improvements in depressive symptoms were observed in the DS group over 36 months [beta = -0.14, (-0.24 to -0.03)], particularly within cognitive and affective domains. Verbal learning performance increased in the DS group [beta = 0.13, (0.01 to 0.24)], whereas psychomotor function improved somewhat in the non-DS group [beta = -0.10, (-0.22 to 0.00)]. Adjusted for ART adherence, odds of HIV nonsuppression did not significantly differ by group [odds ratio = 0.22, (0.04 to 1.23)]; however, greater somatic symptoms at study entry were associated with an increased risk of nonsuppression over time [odds ratio = 2.33 (1.07 to 5.68)].

CONCLUSION

Depressive symptoms were associated with differential neurocognitive trajectories, and somatic depressive symptoms at baseline may predict poorer subsequent HIV suppression. Identifying and treating depressive symptoms at ART initiation may benefit neurocognitive and clinical outcomes in YLWH.

Neurocognitive Effects of Antiretroviral Initiation Among People Living With HIV in Rural Uganda

BACKGROUND

HIV-associated neurocognitive disorders remain prevalent despite effective antiretroviral therapy (ART), but there are limited longitudinal data on people living with HIV (PLWH) in sub-Saharan Africa. We examined neuropsychological (NP) performance in PLWH in a longitudinal study in Uganda.

METHODS

Participants enrolled through the Rakai Community Cohort Study (400 ART-naive PLWH and 400 matched HIV-negative persons) were administered NP assessments. In 2017, PLWH who had initiated ART underwent a 2-year follow-up assessment. Demographically adjusted Z-scores for each NP test were established using data from the HIV- controls. Multivariable linear and logistic regressions were conducted to examine group differences in NP performance. Mixed-effects regressions were conducted to examine ART-related changes in NP outcomes.

RESULTS

Of 333 PLWH who returned for their 2-year follow-up visit, 312 (94%) had initiated ART. Those on ART had a mean age of 35.6 years (SD ± 8.5 years) and mean education of 5.4 years (SD ± 3.3 years); 49% were women. ART-associated NP improvements occurred in verbal learning and memory (P's < 0.05), motor (P's < 0.01), and some measures of processing speed (P = 0.002), whereas there were declines in attention/working memory (P's < 0.001) and semantic fluency (P < 0.001). Pre-ART CD4 count and efavirenz use were associated with a more impaired change in NP performance.

CONCLUSIONS

PLWH in this resource-limited setting showed improved neurocognitive performance on most NP tests after ART initiation. However, the declines in attention/working memory and fluency performance, as well as relationship to efavirenz, warrant further study.

Frailty, Neurocognitive Impairment, or Both in Predicting Poor Health Outcomes Among Adults Living With Human Immunodeficiency Virus

Background

Neurocognitive impairment (NCI) is strongly associated with frailty in people living with human immunodeficiency virus (PLWH); the overlap of frailty and NCI and the impact on health outcomes in PLWH are unknown.

Methods

PLWH in a longitudinal, observational study of aging completed entry evaluations for frailty and NCI. Outcomes of falls (recurrent) increased limitations in independent activities of daily living (IADL), or mortality were combined. Poisson regression models estimated prevalence ratios (PR) for ≥1 outcome over 2 years.

Results

Among 987 participants, the median age at entry was 51 years; 19% were female; the median CD4 count was 616 cells/µL; and HIV-1 RNA was <200 copies/mL in 94%. Most (79%) participants had neither frailty nor NCI; 2% had both; 4% frailty only; and 15% NCI only. Over 2 years of observation, 100 (10%) participants experienced recurrent falls; 175 (18%) had worsening IADL limitations; 17 (2%) died; and 254 (26%) experienced ≥1 poor health outcome. In adjusted models, frailty with NCI was associated with more than double the risk of a poor health outcome (PR 2.65; 95% CI 1.98, 3.54); a significant association was also seen with frailty alone (PR 2.26; 95%CI 1.71, 2.99) and NCI alone (PR 1.73; 95% CI 1.36, 2.20).

Conclusions

The presence of frailty with NCI was associated with a greater risk of falls, disability, or death in PLWH than NCI alone. Interventions that target prevention or reversal of both frailty and NCI (such as increased physical activity) may significantly limit poor health outcomes among PLWH.

Feasibility and Impact of a Yoga Intervention on Cognition, Physical Function, Physical Activity, and Affective Outcomes among People Living with HIV: A Randomized Controlled Pilot Trial

The purpose of this pilot randomized controlled trial is to assess the feasibility and impact of a triweekly 12-week yoga intervention among people living with HIV (PLWH). Additional objectives included evaluating cognition, physical function, medication adherence, health-related quality of life (HRQoL), and mental health among yoga participants versus controls using blinded assessors. We recruited 22 medically stable PLWH aged ≥35 years. A priori feasibility criteria were ≥70% yoga session attendance and ≥70% of participants satisfied with the intervention using a postparticipation questionnaire. Two participants withdrew from the yoga group. Mean yoga class attendance was 82%, with 100% satisfaction. Intention-to-treat analyses (yoga n = 11, control n = 11) showed no within- or between-group differences in cognitive and physical function. The yoga group improved over time in HRQoL cognition (P = .047) with trends toward improvements in HRQoL health transition (P =.063) and depression (P = .055). This pilot study provides preliminary evidence of feasibility and benefits of yoga for PLWH.

Gait Speed Decline Is Associated with Hemoglobin A1C, Neurocognitive Impairment, and Black Race in Persons with HIV

Gait speed declines at a faster rate in persons with HIV (PWH) than in the general population but the risk factors associated with this decline are not well understood. In the AIDS Clinical Trials Group (ACTG) A5322 (HAILO, HIV Infection, Aging, and Immune Function Long-term Observational Study), an observational cohort study of PWH ≥40 years of age, those who developed slow gait during the first 3 years of follow-up were compared with persons who maintained normal speed. Associations with demographic and clinical covariates were assessed using multivariable logistic regression. Of 929 participants, 81% were men, 31% Black, and 20% Hispanic. Median age was 51 years [interquartile range (IQR) = 46-56]. At study entry, 92% had plasma HIV RNA <50 copies/mL with median CD4 count 631 cells/mm³ (IQR = 458-840). At study entry, 7% of participants had slow gait, 16% had neurocognitive impairment (NCI), and 12% had diabetes. Over 3 years, 87% maintained normal gait speed, 3% maintained a slow gait, 6% developed a slow gait, and 4% improved from slow to normal gait speed. In multivariable models, hemoglobin A1C (HbA1C) percentage, per one unit increase [odds ratio (OR) = 1.36; 95% confidence interval (CI) = 1.03-1.81; p = .033], NCI (OR = 3.47; 95% CI = 1.57-7.69 p = .002), and black versus white race (OR = 2.45; 95% CI = 1.08-5.59; p = .032) at entry were significantly associated with development of slow gait compared with those maintaining normal gait speed. The association between baseline HbA1C and development of slow gait speed highlights an intervenable target to prevent progression of physical function limitations.

Longitudinal study of falls among HIV-infected and uninfected women: the role of cognition

BACKGROUND

Although fracture rates are higher in HIV+ than HIV- women, whether HIV infection increases risk of falls is unclear. We determined the longitudinal occurrence and risk factors for falls in the Women's Interagency HIV Study (WIHS), and explored associations with cognitive complaints.

METHODS

Recent (prior 6 months) self-reported falls were collected in 1,816 (1,250 HIV+; 566 HIV-) women over 24 months. Generalized estimating equation models using stepwise selection determined odds of any fall (versus none).

RESULTS

HIV+ women were older than HIV- women (median 49 versus 47 years; P=0.0004), more likely to report neuropathy (20% versus 16%; P=0.023), and had greater central nervous system (CNS) medication use. At least one fall was reported in 41% HIV+ versus 42% HIV- women, including ≥2 falls in 25% HIV+ and 24% HIV- (overall P=0.30). Cognitive complaints were associated with falls among HIV+ (odds ratio [OR] 2.38; 95% CI 1.83, 3.09) and HIV- women (OR 3.43; 95% CI 2.37, 4.97); in adjusted models, cognitive complaints remained significant only in HIV- women (adjusted [aOR] 2.26; 95% CI 1.46, 3.48). Factors associated with any fall in adjusted analyses included: depressive symptoms and neuropathy (both HIV+ and HIV-); age, marijuana use, multiple CNS medications, and HCV infection (HIV+ only); and cognitive complaints, quality of life, hypertension and obesity (HIV- only).

CONCLUSIONS

Middle-aged HIV+ and HIV- women had similar fall rates. Among HIV+ women, factors affecting cognition such as age, depressive symptoms, marijuana use and multiple CNS medications were important predictors of falls, however, cognitive complaints were not.

Heterogeneity in neurocognitive change trajectories among people with HIV starting antiretroviral therapy in Rakai, Uganda

Considerable heterogeneity exists in patterns of neurocognitive change in people with HIV (PWH). We examined heterogeneity in neurocognitive change trajectories from HIV diagnosis to 1-2 years post-antiretroviral therapy (ART). In an observational cohort study in Rakai, Uganda, 312 PWH completed a neuropsychological (NP) test battery at two-time points (ART-naïve, 1-2 years post-ART initiation). All NP outcomes were used in a latent profile analysis to identify subgroups of PWH with similar ART-related neurocognitive change profiles. In a subset, we examined subgroup differences pre-ART on cytokine and neurodegenerative biomarkers CSF levels. We identified four ART-related change subgroups: (1) decline-only (learning, memory, fluency, processing speed, and attention measures), (2) mixed (improvements in learning and memory but declines in attention and executive function measures), (3) no-change, or (4) improvement-only (learning, memory, and attention measures). ART-related NP outcomes that are most likely to change included learning, memory, and attention. Motor function measures were unchanged. Subgroups differed on eight of 34 pre-ART biomarker levels including interleukin (IL)-1β, IL-6, IL-13, interferon-γ, macrophage inflammatory protein-1β, matrix metalloproteinase (MMP)-3, MMP-10, and platelet-derived growth factor-AA. The improvement-only and mixed subgroups showed lower levels on these markers versus the no-change subgroup. These findings provide support for the need to disentangle heterogeneity in ART-related neurocognitive changes, to focus on higher-order cognitive processes (learning, memory, attention) as they were most malleable to change, and to better understand why motor function remained unchanged despite ART treatment. Group differences in pre-ART CSF levels provide preliminary evidence of biological plausibility of neurocognitive phenotyping.

Effect of HIV Subtype and Antiretroviral Therapy on HIV-Associated Neurocognitive Disorder Stage in Rakai, Uganda

BACKGROUND

Combination antiretroviral therapy (ART) improves HIV-associated neurocognitive disorder (HAND) stage in the United States where subtype B predominates, but the effect of ART and subtype on HAND stage in individuals in Uganda with subtypes D and A is largely unknown.

SETTING

A community-based cohort of participants residing in Rakai, Uganda.

METHODS

Three hundred ninety-nine initially ART-naive HIV-seropositive (HIV+) individuals were followed up over 2 years. Neurological and neuropsychological tests and functional assessments were used to determine HAND stage. Frequency and predictors of HAND and HIV-associated dementia (HAD) were assessed at baseline and at follow-up after ART initiation in 312 HIV+ individuals. HIV subtype was determined from gag and env sequences.

RESULTS

At 2-year follow-up, HAD frequency among HIV+ individuals on ART (n = 312) decreased from 13% to 5% (P < 0.001), but the overall frequency of HAND remained unchanged (56%-51%). Subtype D was associated with higher rates of impaired cognition (global deficit score ≥ 0.5) compared with HIV+ individuals with subtype A (55% vs. 24%) (P = 0.008). Factors associated with HAD at baseline were older age, depression, and plasma HIV viral load >100,000 copies/mL. At follow-up, age and depression remained significantly associated with HAD.

CONCLUSIONS

HIV+ individuals on ART in rural Uganda had a significant decrease in the frequency of HAD, but HAND persists after 2 years on ART. The current guideline of immediate ART initiation after HIV diagnosis is likely to greatly reduce HAD in sub-Saharan Africa. Further studies of the effect of HIV subtype and neurocognitive performance are warranted.

Evaluating the Feasibility and Impact of a Yoga Intervention on Cognition, Physical Function, Physical Activity, and Affective Outcomes in People Living With HIV: Protocol for a Randomized Pilot Trial

Background

Despite lower mortality rates due to combination antiretroviral therapy, people living with HIV (PLWH) are grappling with increasingly complex health issues, including cognitive impairments in areas such as memory, attention, processing speed, and motor function. Yoga has been shown to be an effective form of exercise and mindfulness-based stress reduction for many clinical populations. However, no randomized trials have evaluated the impact of yoga on cognitive and physical function among PLWH.

Objective

The aim of this pilot randomized trial was to determine the feasibility of a yoga intervention to lay the groundwork for a full-scale, multisite, community-based trial for PLWH. Specific objectives are to (1) assess the feasibility of study protocol and procedures, (2) compare cognition in the yoga group with the usual care control group after 12 weeks of the intervention in PLWH, and (3) compare the effects of the 12-week yoga intervention versus control on balance, walking speed, physical activity, mental health, medication adherence, and quality of life among PLWH.

Methods

We propose a pilot randomized trial with 2 parallel groups (yoga versus control). We will recruit 25 PLWH (>35 years) from community and health organizations in Halifax, Canada. After baseline assessment with blinded assessors, participants will be randomly assigned to the yoga or control group, using a random computer generator. Participants in the yoga group will engage in supervised 60-min group-based yoga sessions 3 times a week for 12 weeks at a yoga studio. Participants in the control group will maintain their current physical activity levels throughout the study.

Results

As per the Consolidated Standards of Reporting Trials extension for pilot studies, means of all outcomes, mean change, and 95% CIs will be calculated for each group separately. Two-tailed independent t tests and Fisher exact tests will be used to compare groups at baseline. We will analyze quantitative postintervention questionnaire responses using Chi-square tests, and open-ended responses will be analyzed thematically. Intention-to-treat and per-protocol analyses will be used to analyze secondary variables. Changes in outcome variables will be examined between groups and within groups. Effect sizes will be reported for each outcome. A priori adherence and satisfaction criteria will be met if participants attend >70% of the yoga sessions and if >70% of the participants are satisfied with the intervention as determined by a postparticipation questionnaire. Study enrollment began in January 2018, with results expected for October 2019.

Conclusions

This pilot randomized trial will be the first to investigate the feasibility and effect of a yoga intervention on cognitive and physical outcomes among PLWH. This work will inform the feasibility of further investigations in terms of capacity building, participant recruitment and retention, and assessment and intervention protocols.

Trial Registration

ClinicalTrials.gov NCT03071562; https://clinicaltrials.gov/ct2/show/NCT03071562 (Archived by WebCite at http://www.webcitation.org/785sfhWkw)

International Registered Report Identifier (IRRID)

DERR1-10.2196/13818

Randomized Trial of Marine n-3 Polyunsaturated Fatty Acids for the Prevention of Cerebral Small Vessel Disease and Inflammation in Aging (PUFA Trial): Rationale, Design and Baseline Results

Vascular risk factors for age-related cognitive decline are significant, and their management may ultimately prove the most successful strategy for reducing risk and sustaining cognitive health. This randomized, double-blinded, placebo-controlled trial with parallel group allocation to either marine n-3 polyunsaturated fatty acids (n-3 PUFA) or soybean oil placebo assesses the effects on the total volume of accumulation in cerebral white matter hyperintensities (WMH), a potentially modifiable neurovascular component of age-related cognitive decline. Total WMH accumulation over 3 years is the primary endpoint. The safety and efficacy of n-3 PUFA is evaluated in older adults with significant WMH and suboptimum plasma n-3 PUFA as inclusion criteria. One hundred and two non-demented older adults were enrolled with a mean age of 81.1 (±4.4) years, WMH of 19.4 (±16.1) cm³, and a plasma n-3 PUFA of 86.64 (±29.21) µg/mL. 61% were female, 28% were apolipoprotein E epsilon 4 carriers, and the mean mini-mental state exam (MMSE) was 27.9 (±1.7). This trial provides an initial evaluation of n-3 PUFA effects on WMH, a reproducible and valid risk biomarker for cognitive decline, as well as on inflammatory biomarkers thought to play a role in WMH accumulation. We present the baseline results and operational experience of enriching a study population on advanced age, blood n-3 PUFA, and magnetic resonance imaging (MRI) derived WMH with biomarker outcomes (WMH, inflammation markers) in a dementia prevention paradigm.

Extrapyramidal motor signs in older adults with HIV disease: frequency, 1-year course, and associations with activities of daily living and quality of life

Age and HIV disease have additive effects on neural systems that support motor functioning. The current study examined the combined impact of aging and HIV on extrapyramidal motor functions, which were hypothesized to influence on activities of daily living (ADLs) and quality of life (QoL). Participants included 336 adults classified by HIV serostatus and age. A research nurse administered the Unified Parkinson's Disease Rating Scale (UPDRS) and participants completed the modified Lawton & Brody ADL and the Short Form Survey Instrument (SF-36) questionnaires as part of a larger neuropsychological research battery. A convenience subset of 172 participants completed a 14-month follow-up evaluation. At baseline, only older age was associated with mild extrapyramidal signs; however, at 14-month follow-up, independent adverse effects of both HIV status and age group were observed on a 3-level UPDRS change variable. Among older HIV+ adults, the presence of mild UPDRS motor signs was independently associated with basic and instrumental ADL dependence, as well as lower physical (ps < .05), but not mental QoL. In the modern treatment era, older HIV+ adults show higher frequency of mild extrapyramidal signs as compared to younger individuals (but not older HIV- persons) and are at higher risk of incident extrapyramidal signs relative to HIV- persons (but not younger HIV+ persons). When present in older HIV+ adults, extrapyramidal signs are of mild severity but nevertheless increase the risk of daily functioning problems and lower health-related physical QoL.

The relationship between cognitive change and physical health and behavioural outcomes in a Ugandan cohort of adults living with HIV - a longitudinal study

We investigated changes in cognitive function and physical health and behavioural outcomes (HIV disease progression, health-seeking behaviour, adherence to HIV medications and risky sexual behaviour) at baseline and 12 months later among 1126 Ugandan adults living with HIV. Overall, cognitive function improved from baseline to follow-up, except for gait speed, which was slower at follow-up compared to baseline. There were improvements in physical health and behavioural outcomes by follow-up, with greater improvements among individuals on ART compared to those not on ART. Change in gait speed over time significantly predicted risky sexual behaviours at follow-up. This is the first study to investigate the longitudinal relationships between cognitive function and health outcomes among Ugandan adults living with HIV and provide insights into the possible links between cognitive function and negative clinical and behavioural health outcomes in people living with HIV.

Fall Risk Assessment Metrics for Elderly Patients With Hip Fractures

The most common surgery performed by orthopedic surgeons likely involves that for hip fractures. The incidence of hip fractures is anticipated to rise in the coming decades. Hip fractures most commonly occur in elderly women with osteoporosis after a fall from standing position. In an effort to reduce the incidence, improve the postoperative care, and accelerate the rehabilitation of hip fractures, it is important to evaluate the fall risk of these patients, as it is an objective indication of their level of physical activity. Metrics currently available for the evaluation of fall risk in the elderly vary widely, with each having been designed to assess a specific patient population. However, their applicability has often proved to be much broader than expected. This review summarizes the metrics available for fall risk assessment of elderly patients with hip fractures, describes their individual features and efficacy, and highlights those that seem to be more reliable for the assessment of rehabilitation of these patients after hip fracture surgery. [Orthopedics. 2018; 41(3):142-156.].

Motor function declines over time in human immunodeficiency virus and is associated with cerebrovascular disease, while HIV-associated neurocognitive disorder remains stable

HIV-associated neurocognitive disorders (HAND) remain prevalent in the combined antiretroviral therapy (CART) era, especially the milder forms. Despite these milder phenotypes, we have shown that motor abnormalities persist and have quantified them with the HIV Dementia Motor Scale (HDMS). Our objectives were to replicate, in an independent sample, our prior findings that the HDMS is associated with cognitive impairment in HIV, while adding consideration of age-associated comorbidities such as cerebrovascular disease, and to examine the longitudinal trajectories of cognitive and motor dysfunction. We included all participants enrolled in the Manhattan HIV Brain Bank (MHBB) from January 2007 to May 2017 who had complete baseline data (N = 164). MHBB participants undergo standardized longitudinal assessments including documentation of comorbidities and medications, blood work, the HDMS, and neurocognitive testing. We found that motor dysfunction, cognitive impairment, and cerebrovascular disease were significantly associated with each other at baseline. Cerebrovascular disease independently predicted cognitive impairment in a multivariable model. Longitudinal analysis in a subset of 78 participants with ≥ 4 years of follow-up showed a stable cognition but declining motor function. We conclude that the HDMS is a valid measurement of motor dysfunction in HIV-infected patients and is associated with cognitive impairment and the presence of cerebrovascular disease. Cognitive impairment is mild and stable in CART-treated HIV; however, motor function declines over time, which may be related to the accrual of comorbidities such as cerebrovascular disease. Further research should examine the mechanisms underlying motor dysfunction in HIV and its clinical impact.

The Montreal Cognitive Assessment-Basic (MoCA-B) is not a reliable screening tool for cognitive decline in HIV patients receiving combination antiretroviral therapy in rural South Africa

BACKGROUND

HIV-associated neurocognitive disorders (HAND) are frequently occurring comorbidities in HIV-positive patients, diagnosed by means of a neuropsychological assessment (NPA). Due to the magnitude of the HIV-positive population in Sub-Saharan Africa, easy-to-use cognitive screening tools are essential.

METHODS

This was a cross-sectional clinical trial involving 44 HIV-positive patients (on stable cART) and 73 HIV-negative controls completing an NPA, the International HIV Dementia Scale (IHDS), and a culturally appropriate cognitive screening tool, the Montreal Cognitive Assessment-Basic (MoCA-B). HAND were diagnosed by calculating Z-scores using internationally published normative data on NPA, as well as by using data from the HIV-negative group to validate the MoCA-B.

RESULTS

One hundred and seventeen patients were included (25% male, median age 35 years, median 11 years of education). A moderate correlation was found between the MoCA-B and NPA total Z-score (Pearson's r=0.36, p=0.02). Area under the curve (AUC) values for MoCA-B and IHDS were 0.59 and 0.70, respectively. The prevalence of HAND in HIV-positive patients was 66% when calculating Z-scores using published normative data versus 48% when using the data from the present HIV-negative cohort.

CONCLUSION

The MoCA-B appeared not to be a valid screening tool for HAND in this setting. The prevalence of HAND in this setting is high, but appeared overestimated when using published norms.

Motor-related brain abnormalities in HIV-infected patients: a multimodal MRI study

PURPOSE

It is generally believed that HIV infection could cause HIV-associated neurocognitive disorders (HAND) across a broad range of functional domains. Some of the most common findings are deficits in motor control. However, to date no neuroimaging studies have evaluated basic motor control in HIV-infected patients using a multimodal approach.

METHODS

In this study, we utilized high-resolution structural imaging and task-state functional magnetic resonance imaging (fMRI) to assess brain structure and motor function in a homogeneous cohort of HIV-infected patients.

RESULTS

We found that HIV-infected patients had significantly reduced gray matter (GM) volume in cortical regions, which are involved in motor control, including the bilateral posterior insula cortex, premotor cortex, and supramarginal gyrus. Increased activation in bilateral posterior insula cortices was also demonstrated by patients during hand movement tasks compared with healthy controls. More importantly, the reduced GM in bilateral posterior insula cortices was spatially coincident with abnormal brain activation in HIV-infected patients. In addition, the results of partial correlation analysis indicated that GM reduction in bilateral posterior insula cortices and premotor cortices was significantly correlated with immune system deterioration.

CONCLUSION

This study is the first to demonstrate spatially coincident GM reduction and abnormal activation during motor performance in HIV-infected patients. Although it remains unknown whether the brain deficits can be recovered, our findings may yield new insights into neurologic injury underlying motor dysfunction in HAND.

Objective impairments of gait and balance in adults living with HIV-1 infection: a systematic review and meta-analysis of observational studies

BACKGROUND

Gait and balance deficits are reported in adults with HIV infection and are associated with reduced quality of life. Current research suggests an increased fall-incidence in this population, with fall rates among middle-aged adults with HIV approximating that in seronegative elderly populations. Gait and postural balance rely on a complex interaction of the motor system, sensory control, and cognitive function. However, due to disease progression and complications related to ongoing inflammation, these systems may be compromised in people with HIV. Consequently, locomotor impairments may result that can contribute to higher-than-expected fall rates. The aim of this review was to synthesize the evidence regarding objective gait and balance impairments in adults with HIV, and to emphasize those which could contribute to increased fall risk.

METHODS

This review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. An electronic search of published observational studies was conducted in March 2016. Methodological quality was assessed using the NIH Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies. Narrative synthesis of gait and balance outcomes was performed, and meta-analyses where possible.

RESULTS

Seventeen studies were included, with fair to low methodological quality. All studies used clinical tests for gait-assessment. Gait outcomes assessed were speed, initiation-time and cadence. No studies assessed kinetics or kinematics. Balance was assessed using both instrumented and clinical tests. Outcomes were mainly related to center of pressure, postural reflex latencies, and timed clinical tests. There is some agreement that adults with HIV walk slower and have increased center of pressure excursions and -long loop postural reflex latencies, particularly under challenging conditions.

CONCLUSIONS

Gait and balance impairments exist in people with HIV, resembling fall-associated parameters in the elderly. Impairments are more pronounced during challenging conditions, might be associated with disease severity, are not influenced by antiretroviral therapy, and might not be associated with peripheral neuropathy. Results should be interpreted cautiously due to overall poor methodological quality and heterogeneity. Locomotor impairments in adults with HIV are currently insufficiently quantified. Future research involving more methodological uniformity is warranted to better understand such impairments and to inform clinical decision-making, including fall-prevention strategies, in this population.

Online learning of gait models for calculation of gait parameters

This paper proposes a novel approach for gait analysis from wearable sensing, based on an adaptive periodic model of any gait signal. The proposed method learns a model of the gait cycle during online measurement, using a continuous representation that can adapt to inter and intra-personal variability by creating an individualized model. Once the algorithm has converged to the input signal, key gait events can be identified relative to the estimated gait phase; these events can then be used to calculate gait parameters. The approach is implemented and tested on a human motion dataset where heel impact and toe takeoff events are extracted with an average error of 0.04 cycles.

Cognitive function in early HIV infection

This study aimed to examine cognitive function in acute/early HIV infection over the subsequent 2 years. Fifty-six HIV+ subjects and 21 seronegative participants of the Chicago Early HIV Infection Study were evaluated using a comprehensive neuropsychological assessment at study enrollment and at 2-year follow-up. Cognitive performance measures were compared in the groups using t tests and mixed-effect models. Patterns of relationship with clinical measures were determined between cognitive function and clinical status markers using Spearman's correlations. At the initial timepoint, the HIV group demonstrated significantly weaker performance on measures of verbal memory, visual memory, psychomotor speed, motor speed, and executive function. A similar pattern was found when cognitive function was examined at follow-up and across both timepoints. The HIV subjects had generally weaker performance on psychomotor speed, executive function, motor speed, visual memory, and verbal memory. The rate of decline in cognitive function across the 2-year follow-up period did not differ between groups. Correlations between clinical status markers and cognitive function at both timepoints showed weaker performance associated with increased disease burden. Neurocognitive difficulty in chronic HIV infection may have very early onset and reflect consequences of initial brain viral invasion and neuroinflammation during the intense, uncontrolled viremia of acute HIV infection. Further characterization of the changes occurring in initial stages of infection and the risk and protective factors for cognitive function could inform new strategies for neuroprotection.

Prevalence of neurocognitive disorders and depression in a Brazilian HIV population

INTRODUCTION

Combined antiretroviral therapy has enabled human immunodeficiency virus (HIV) carriers to live longer. This increased life expectancy is associated with the occurrence of degenerative diseases, including HIV-associated neurocognitive disorders (HAND), which are diagnosed via a complex neuropsychological assessment. The International HIV Dementia Scale (IHDS) is a screening instrument validated in Brazil for use in the absence of neuropsychological evaluation. HIV patients are frequently diagnosed with depression. We aimed to determine the prevalence of neurocognitive impairment using the IHDS and depressive disorders using the Hamilton Rating Scale for Depression (HAM-D17), compare the IHDS performance with the performances on the Timed Gait Test (TGT), the Digit Symbol Coding Test (DS) and the Brazilian version of the Scale of Instrumental Activities of Daily Living (IADL), and evaluate the association between the IHDS performance and clinical-demographic variables.

METHODS

One hundred fourteen patients were evaluated in a cross-sectional study conducted in a public outpatient clinic for infectious diseases in Marília City, State of São Paulo, Brazil. Data were collected following consultation. Statistical analysis was performed in accordance with the nature and distribution of the data and hypotheses.

RESULTS

According to the IHDS, 53.2% of the sampled patients were neuropsychologically impaired. According to the HAM-D17, 26.3% had depressive disorders. There were significant associations between the IHDS and the TGT and DS. Multiple regression analysis indicated that female gender, educational level, and cluster of differentiation 4 (CD4) levels were significantly and independently associated with neurocognitive impairment.

CONCLUSIONS

The prevalence of neurocognitive impairment according to the IHDS is high and associated with female gender, education level, and low CD4 levels.

HIV-1 proteins, Tat and gp120, target the developing dopamine system

In 2014, 3.2 million children (< 15 years of age) were estimated to be living with HIV and AIDS worldwide, with the 240,000 newly infected children in the past year, i.e., another child infected approximately every two minutes [1]. The primary mode of HIV infection is through mother-to-child transmission (MTCT), occurring either in utero, intrapartum, or during breastfeeding. The effects of HIV-1 on the central nervous system (CNS) are putatively accepted to be mediated, in part, via viral proteins, such as Tat and gp120. The current review focuses on the targets of HIV-1 proteins during the development of the dopamine (DA) system, which appears to be specifically susceptible in HIV-1-infected children. Collectively, the data suggest that the DA system is a clinically relevant target in chronic HIV-1 infection, is one of the major targets in pediatric HIV-1 CNS infection, and may be specifically susceptible during development. The present review discusses the development of the DA system, follows the possible targets of the HIV-1 proteins during the development of the DA system, and suggests potential therapeutic approaches. By coupling our growing understanding of the development of the CNS with the pronounced age-related differences in disease progression, new light may be shed on the neurological and neurocognitive deficits that follow HIV-1 infection.

Aging with HIV-1 Infection: Motor Functions, Cognition, and Attention--A Comparison with Parkinson's Disease

Recent advances in highly active anti-retroviral therapy (HAART) in their various combinations have dramatically increased the life expectancies of HIV-infected persons. People diagnosed with HIV are living beyond the age of 50 but are experiencing the cumulative effects of HIV infection and aging on brain function. In HIV-infected aging individuals, the potential synergy between immunosenescence and HIV viral loads increases susceptibility to HIV-related brain injury and functional brain network degradation similar to that seen in Parkinson's disease (PD), the second most common neurodegenerative disorder in the aging population. Although there are clear diagnostic differences in the primary pathology of both diseases, i.e., death of dopamine-generating cells in the substantia nigra in PD and neuroinflammation in HIV, neurotoxicity to dopaminergic terminals in the basal ganglia (BG) has been implied in the pathogenesis of HIV and neuroinflammation in the pathogenesis of PD. Similar to PD, HIV infection affects structures of the BG, which are part of interconnected circuits including mesocorticolimbic pathways linking brainstem nuclei to BG and cortices subserving attention, cognitive control, and motor functions. The present review discusses the combined effects of aging and neuroinflammation in HIV individuals on cognition and motor function in comparison with age-related neurodegenerative processes in PD. Despite the many challenges, some HIV patients manage to age successfully, most likely by redistribution of neural network resources to enhance function, as occurs in healthy elderly; such compensation could be curtailed by emerging PD.

Antiretroviral treatment initiation does not differentially alter neurocognitive functioning over time in youth with behaviorally acquired HIV

Although youth living with behaviorally acquired HIV (YLWH) are at risk for cognitive impairments, the relationship of impairments to HIV and potential to improve with antiretroviral therapy (ART) are unclear. This prospective observational study was designed to examine the impact of initiation and timing of ART on neurocognitive functioning in YLWH in the Adolescent Medicine Trials Network for HIV/AIDS Interventions. Treatment naïve YLWH age 18-24 completed baseline and four additional assessments of attention/working memory, complex executive, and motor functioning over 3 years. Group 1 co-enrolled in an early ART initiation study and initiated ART at enrollment CD4 >350 (n = 56); group 2 had CD4 >350 and were not initiating ART (n = 66); group 3 initiated ART with CD4 <350 (n = 59) per standard of care treatment guidelines at the time. Treatment was de-intensified to boosted protease inhibitor monotherapy at 48 weeks for those in group 1 with suppressed viral load. Covariates included demographic, behavioral, and medical history variables. Analyses used hierarchical linear modeling. All groups showed improved performance with peak at 96 weeks in all three functional domains. Trajectories of change were not significantly associated with treatment, timing of treatment initiation, or ART de-intensification. Demographic variables and comorbidities were associated with baseline functioning but did not directly interact with change over time. In conclusion, YLWH showed improvement in neurocognitive functioning over time that may be related to practice effects and nonspecific impact of study participation. Neither improvement nor decline in functioning was associated with timing of ART initiation or therapy de-intensification.

Functional impairment, disability, and frailty in adults aging with HIV-infection

The integration of antiretroviral therapy (i.e., ART) into HIV care has dramatically extended the life expectancy of those living with HIV. However, in comparison to similar HIV-uninfected populations, HIV-infected persons experience an excess of morbidity and mortality with an early onset of aging complications including neurocognitive decline, osteoporosis, impaired physical function, frailty, and falls. Recent consensus guidelines encourage clinicians and researchers to consider functional impairment of HIV-infected adults as a measure to understand the impact of aging across a range of abilities. Despite the importance of assessing function in persons aging with HIV infection, a lack of consistent terminology and standardization of assessment tools has limited the application of functional assessments in clinical or research settings. Herein, we distinguish between different approaches used to assess function, describe what is known about function in the aging HIV population, and consider directions for future research.

Predictors of neurocognitive outcomes on antiretroviral therapy after cryptococcal meningitis: a prospective cohort study

Cryptococcal meningitis is the most common cause of adult meningitis in Africa, yet neurocognitive outcomes are unknown. We investigated the incidence and predictors of neurologic impairment among cryptococcal survivors. HIV-infected, antiretroviral-naive Ugandans with cryptococcal meningitis underwent standardized neuropsychological testing at 1, 3, 6, and 12 months. A quantitative neurocognitive performance z-score (QNPZ) was calculated based on population z-scores from HIV-negative Ugandans (n = 100). Comparison was made with an HIV-infected, non-meningitis cohort (n = 110). Among 78 cryptococcal meningitis survivors with median CD4 count of 13 cells/μL (interquartile range: 6-44), decreased global cognitive function occurred through 12 months compared with the HIV-infected, non-cryptococcosis cohort (QNPZ-6 at 12 months, P = 0.036). Tests of performance in eight cognitive domains was impaired 1 month after cryptococcal diagnosis; however, cryptococcal meningitis survivors improved their global neurocognitive function over 12 months with residual impairment (mean z-scores < -1), only in domains of motor speed, gross motor and executive function at 12 months. There was no evidence that neurocognitive outcome was associated with initial demographics, HIV parameters, or meningitis severity. Paradoxically, persons with sterile CSF cultures after 14 days of induction amphotericin therapy had worse neurocognitive outcomes than those still culture-positive at 14 days (P = 0.002). Cryptococcal meningitis survivors have significant short-term neurocognitive impairment with marked improvement over the first 12 months. Few characteristics related to severity of cryptococcosis, including Cryptococcus burden, were associated with neurocognitive outcome.

Neurocognitive functioning in antiretroviral therapy-naïve youth with behaviorally acquired human immunodeficiency virus

PURPOSE

Youth living with human immunodeficiency virus (HIV) account for over one third of new HIV infections and are at high risk of adverse psychosocial, everyday living, and health outcomes. Human immunodeficiency virus-associated neurocognitive disorders (HAND) are known to affect health outcomes of HIV-infected adults even in the era of combination antiretroviral therapy. Thus, the current study aimed to characterize the prevalence and clinical correlates of HAND in youth living with HIV. Here, we report baseline neurocognitive data for behaviorally HIV-infected youth enrolled in a prospective study evaluating strategies of antiretroviral treatment initiation and use.

METHODS

A total of 220 participants, age 18-24 years, who were naive to treatment (except for prevention of mother-to-child HIV transmission; n = 3), completed a comprehensive neurocognitive, substance use, and behavioral health assessment battery.

RESULTS

Sixty-seven percent of youth met criteria for HAND (96.4% were asymptomatic and 3.5% were syndromic); deficits in episodic memory and fine-motor skills emerged as the most commonly affected ability areas. Multivariable models showed that lower CD4 count, longer time since HIV diagnosis, and high-risk alcohol use were uniquely associated with neurocognitive deficits.

CONCLUSIONS

Over two thirds of youth with behaviorally acquired HIV evidence neurocognitive deficits, which have modest associations with more advanced HIV disease as well as other factors. Research is needed to determine the impact of such neuropsychiatric morbidity on mental health and HIV disease treatment outcomes (e.g., nonadherence) and transition to independent living responsibilities in HIV-infected youth, as well as its long-term trajectory and possible responsiveness to cognitive rehabilitation and pharmacotherapy.

A novel computerized functional assessment for human immunodeficiency virus-associated neurocognitive disorder

Human immunodeficiency virus (HIV)-associated neurocognitive disorder (HAND) is present in 30-60 % of HIV-positive (HIV+) individuals and can be assessed by neuropsychological testing and level of functional impairment. HAND diagnosis therefore requires accurate assessment of functional impairment. The Computer Assessment of Mild Cognitive Impairment (CAMCI) is a computer-based screening tool that includes performance-based measures of functional impairment. We sought to evaluate the CAMCI as a functional assessment tool in HAND. One hundred fourteen HIV+ patients and 38 HIV-negative (HIV-) patients underwent neuropsychological and CAMCI testing. Cognitive status for HIV+ subjects was classified using the Frascati criteria. HIV+ subjects grouped together and classified by cognitive impairment performed worse than HIV- subjects on several of the CAMCI tasks, including following directions to the supermarket (p = 0.05, p = 0.03), recalling which items to purchase (p = 0.01, p = 0.02), and remembering to stop at a supermarket (p < 0.01, p = 0.01) and the post office (p < 0.01, p = 0.03). After controlling for hepatitis C status and depression symptomatology, the tasks "following directions to the supermarket" and the "recalling which items to purchase" were no longer significant. The "remembering to run two separate errands" tasks retained their significance (p < 0.01 for both tasks). A subset of the CAMCI tasks therefore successfully differentiated HIV+ patients from HIV- individuals. Differences in hepatitis C status and depression symptomatology could account for some of the function assessment differences in the CAMCI. These results suggest the CAMCI could be a useful objective performance-based functional assessment in patients with HIV.

Evaluation of brief screening tools for neurocognitive impairment in HIV/AIDS: a systematic review of the literature

OBJECTIVE(S)

To systematically review literature on brief screening tools used to detect and differentiate between normal cognition and neurocognitive impairment and HIV-associated neurocognitive disorders (HANDs) in adult populations of persons with HIV.

DESIGN

A formal systematic review.

METHODS

We searched six electronic databases in 2011 and contacted experts to identify relevant studies published through May 2012. We selected empirical studies that focused on evaluating brief screening tools (<20 min) for neurocognitive impairment in persons with HIV. Two reviewers independently reviewed retrieved literature for potential relevance and methodological quality. Meta-analyses were completed on screening tools that had sufficient data.

RESULTS

Fifty-one studies met inclusion criteria; we focused on 31 studies that compared brief screening tools with reference tests. Within these 31 studies, 39 tools were evaluated and 67% used a comprehensive neuropsychological battery as a reference. The majority of these studies evaluated HIV-associated dementia (HAD). Meta-analyses demonstrated that the HIV Dementia Scale (HDS) has poor pooled sensitivity (0.48) and the International HIV Dementia Scale (IHDS) has moderate pooled sensitivity (0.62) in detecting a range of cognitive impairment. Five newer screening tools had relatively good sensitivities (>0.70); however, none of the tools differentiated HAND conditions well enough to suggest broader use. There were significant methodological shortcomings noted in most studies.

CONCLUSION

HDS and IHDS perform well to screen for HAD but poorly for milder HAND conditions. Further investigation, with improved methodology, is required to understand the utility of newer screening tools for HAND; further tools may need to be developed for milder HAND conditions.

Improved neurocognitive test performance in both arms of the SMART study: impact of practice effect

We evaluated factors associated with improvement in neurocognitive performance in 258 HIV-infected adults with baseline CD4 lymphocyte counts above 350 cells/mm³ randomized to intermittent, CD4-guided antiretroviral therapy (ART) (128 participants) versus continuous therapy (130) in the Neurology substudy of the Strategies for Management of Antiretroviral Therapy trial. Participants were enrolled in Australia, North America, Brazil, and Thailand, and neurocognitive performance was assessed by a five-test battery at baseline and month 6. The primary outcome was change in the quantitative neurocognitive performance z score (QNPZ-5), the average of the z scores of the five tests. Associations of the 6-month change in test scores with ART use, CD4 cell counts, HIV RNA levels, and other factors were determined using multiple regression models. At baseline, median age was 40 years, median CD4 cell count was 513 cells/mm³, 88 % had plasma HIV RNA ≤ 400 copies/mL, and mean QNPZ-5 was -0.68. Neurocognitive performance improved in both treatment groups by 6 months; QNPZ-5 scores increased by 0.20 and 0.13 in the intermittent and continuous ART groups, respectively (both P < 0.001 for increase and P = 0.26 for difference). ART was used on average for 3.6 and 5.9 out of the 6 months in the intermittent and continuous ART groups, respectively, but the increase in neurocognitive test scores could not be explained by ART use, changes in CD4, or plasma HIV RNA, which suggests a practice effect. The impact of a practice effect after 6 months emphasizes the need for a control group in HIV studies that measure intervention effects using neurocognitive tests similar to ours.

Neurobehavioral alterations in HIV-1 transgenic rats: evidence for dopaminergic dysfunction

Clinical studies have provided evidence that the progression of HIV-1-associated neurocognitive disorders (HAND) involves alterations in dopamine (DA) systems. Drugs of abuse that act on the brain DA system, such as cocaine (Coc), may exacerbate HIV-1 infection and consequent behavioral and neurological manifestations. In the present study, we used the HIV-1 transgenic (Tg) rat, which constitutively expresses 7 of the 9 HIV-1 genes, to assess potential DA system alterations in three behavioral assays: prepulse inhibition (PPI) of the auditory startle response (ASR), novelty and habituation/retention, and sensitization to Coc across repeated administration. Adult female Sprague-Dawley rats were tested in each experiment. The HIV-1 Tg animals were hyperreactive to auditory startle stimuli and displayed a leftward shift in the temporal window for maximal PPI, suggesting an alteration in sensorimotor gating. All animals displayed an initial robust locomotor response to a novel environment which dissipated with repeated testing; however, the HIV-1 Tg rats, relative to controls, consistently showed a weaker novelty response across monthly-spaced assessments. The HIV-1 Tg animals also showed decreased intrasession habituation of motor activity across 3-day periods that emerged across monthly-spaced locomotor activity sessions; a pattern consistent with impaired long-term episodic memory. Furthermore, the HIV-1 Tg group displayed differential cocaine-induced sensitization, observed both in initiation across the 10-day cocaine treatment, and in expression following a cocaine rechallenge after a 7-day abstinence. Collectively, the present data implicate that the non-infectious HIV-1 Tg rat, which resembles the complete suppression of infection in HIV-1 positive individuals under CART, displays sustained, if not permanent, alterations in the brain DA system.

Design and testing of statistical methods to classify the severity of steppage gait based on center of pressure data

In this research kinematics parameters derived from ground reaction forces were evaluated to limit differential diagnoses and measure the degree of disabilities during walking among neuropathic subjects. 25 neuropathic subjects affected by drop foot and 20 normal subjects were enrolled in the study. Each subject was tested in average 10±2 times for calculating kinetics parameters derived from ground reaction forces. The results revealed that the center of pressure displacement pattern in sole of foot can be a good index for differential diagnoses and measuring the degree of disabilities. This research can extend the clinical applications of ground reaction force plate and introduce suitable criteria to measure the degree of disability among neuropathic patients.

Lessons learned developing a diagnostic tool for HIV-associated dementia feasible to implement in resource-limited settings: pilot testing in Kenya

Objective

To conduct a preliminary evaluation of the utility and reliability of a diagnostic tool for HIV-associated dementia (HAD) for use by primary health care workers (HCW) which would be feasible to implement in resource-limited settings.

Background

In resource-limited settings, HAD is an indication for anti-retroviral therapy regardless of CD4 T-cell count. Anti-retroviral therapy, the treatment for HAD, is now increasingly available in resource-limited settings. Nonetheless, HAD remains under-diagnosed likely because of limited clinical expertise and availability of diagnostic tests. Thus, a simple diagnostic tool which is practical to implement in resource-limited settings is an urgent need.

Methods

A convenience sample of 30 HIV-infected outpatients was enrolled in Western Kenya. We assessed the sensitivity and specificity of a diagnostic tool for HAD as administered by a primary HCW. This was compared to an expert clinical assessment which included examination by a physician, neuropsychological testing, and in selected cases, brain imaging. Agreement between HCW and an expert examiner on certain tool components was measured using Kappa statistic.

Results

The sample was 57% male, mean age was 38.6 years, mean CD4 T-cell count was 323 cells/µL, and 54% had less than a secondary school education. Six (20%) of the subjects were diagnosed with HAD by expert clinical assessment. The diagnostic tool was 63% sensitive and 67% specific for HAD. Agreement between HCW and expert examiners was poor for many individual items of the diagnostic tool (K = .03–.65). This diagnostic tool had moderate sensitivity and specificity for HAD. However, reliability was poor, suggesting that substantial training and formal evaluations of training adequacy will be critical to enable HCW to reliably administer a brief diagnostic tool for HAD.

HIV-1 effects on neuropsychological performance in a resource-limited country, Zambia

Zambia has substantially been affected by the HIV/AIDS epidemic with prevalence rates at 14% in a population estimated at 12 million. Yet, the extent of HIV-associated neurocognitive disorders (HAND) in this population remains to be clearly understood. A series of culturally appropriate neuropsychological (NP) assessments [International HIV Dementia Scale (IHDS), Color Trails Test 1 and 2, Grooved pegboard Test, and Time Gait Test] were used to test the effects of HIV on NP performance of HIV seropositive and seronegative individuals. Twenty-two percent HIV positive individuals ARV naïve met the criteria for IHDS-defined NP impairment. Gender significantly influenced the performance on NP tests with females performing more poorly compared to males. Larger studies that will accommodate gender differences and age are necessary to generate appropriate norms in Zambia in order to better assess the prevalence of HAND in the developing country setting.

HIV-1 infection and cognitive impairment in the cART era: a review

With the introduction of combination antiretroviral therapy AIDS dementia complex or HIV-associated dementia, as it was termed later, largely disappeared in clinical practice. However, in the past few years, patients, long-term infected and treated, including those with systemically well controlled infection, started to complain about milder memory problems and slowness, difficulties in concentration, planning, and multitasking. Neuropsychological studies have confirmed that cognitive impairment occurs in a substantial (15-50%) proportion of patients. Among HIV-1-infected patients cognitive impairment was and is one of the most feared complications of HIV-1 infection. In addition, neurocognitive impairment may affect adherence to treatment and ultimately result in increased morbidity for systemic disease. So what may be going on in the CNS after so many years of apparently controlled HIV-1 infection is an urgent and important challenge in the field of HIV medicine. In this review we summarize the key currently available data. We describe the clinical neurological and neuropsychological findings, the preferred diagnostic approach with new imaging techniques and cerebrospinal fluid analysis. We try to integrate data on pathogenesis and finally discuss possible therapeutic interventions.

Pontocerebellar contribution to postural instability and psychomotor slowing in HIV infection without dementia

Postural instability occurs in HIV infection, but quantitative balance tests in conjunction with neuroimaging are lacking. We examined whether infratentorial brain tissue volume would be deficient in nondemented HIV-infected individuals and whether selective tissue deficits would be related to postural stability and psychomotor speed performance. The 123 participants included 28 men and 12 women with HIV infection without dementia or alcohol use disorders, and 40 men and 43 women without medical or psychiatric conditions. Participants completed quantitative balance testing, Digit Symbol test, and a test of finger movement speed and dexterity. An infratentorial brain region, supratentorial ventricular system, and corpus callosum were quantified with MRI-derived atlas-based parcellation, and together with archival DTI-derived fiber tracking of pontocerebellar and internal and external capsule fiber systems, brain measures were correlated with test performance. The tissue ratio of the infratentorium was ~3% smaller in the HIV than control group. The HIV group exhibited performance deficits in balancing on one foot, walking toe-to-heel, Digit Symbol substitution task, and time to complete all Digit Symbol grid boxes. Total infratentorial tissue ratio was a significant predictor of balance and Digit Symbol scores. Balance scores did not correlate significantly with ventricular volumes, callosal size, or internal or external capsule fiber integrity but did so with indices of pontocerebellar tract integrity. HIV-infected individuals specifically recruited to be without complications from alcohol use disorders had pontocerebellar tissue volume deficits with functional ramifications. Postural stability and psychomotor speed were impaired and attributable, at least in part, to compromised infratentorial brain systems.

Cardiovascular risk factors associated with lower baseline cognitive performance in HIV-positive persons

OBJECTIVE

To determine factors associated with baseline neurocognitive performance in HIV-infected participants enrolled in the Strategies for Management of Antiretroviral Therapy (SMART) neurology substudy.

METHODS

Participants from Australia, North America, Brazil, and Thailand were administered a 5-test neurocognitive battery. Z scores and the neurocognitive performance outcome measure, the quantitative neurocognitive performance z score (QNPZ-5), were calculated using US norms. Neurocognitive impairment was defined as z scores <-2 in two or more cognitive domains. Associations of test scores, the QNPZ-5, and impairment with baseline factors including demographics and risk factors for HIV-associated dementia (HAD) and cardiovascular disease (CVD) were determined in multiple regression.

RESULTS

The 292 participants had a median CD4 cell count of 536 cells/mm(3), 88% had an HIV viral load < or =400 copies/mL, and 92% were taking antiretrovirals. Demographics, HIV, and clinical factors differed between locations. The mean QNPZ-5 score was -0.72; 14% of participants had neurocognitive impairment. For most tests, scores and z scores differed significantly between locations, with and without adjustment for age, sex, education, and race. Prior CVD was associated with neurocognitive impairment. Prior CVD, hypercholesterolemia, and hypertension were associated with poorer neurocognitive performance but conventional HAD risk factors and the CNS penetration effectiveness rank of antiretroviral regimens were not.

CONCLUSIONS

In this HIV-positive population with high CD4 cell counts, neurocognitive impairment was associated with prior CVD. Lower neurocognitive performance was associated with prior CVD, hypertension, and hypercholesterolemia, but not conventional HAD risk factors. The contribution of CVD and cardiovascular risk factors to the neurocognition of HIV-positive populations warrants further investigation.

Neurobehavioral performance in feline immunodeficiency virus infection: integrated analysis of viral burden, neuroinflammation, and neuronal injury in cortex

Human immunodeficiency virus (HIV) infection causes motor and neurocognitive abnormalities affecting >50% of children and 20% of adults with HIV/AIDS (acquired immunodeficiency syndrome). The closely related lentivirus, feline immunodeficiency virus (FIV), also causes neurobehavioral deficits. Herein, we investigated the extent to which FIV infection affected specific motor and cognitive tasks in conjunction with viral burden and immune responses within the brain. Neonatal animals were infected with a neurovirulent FIV strain (FIV-Ch) and assessed in terms of systemic immune parameters, viral burden, neurobehavioral performance, and neuropathological features. FIV-infected animals displayed less weight gain and lower blood CD4(+) T-cell levels than mock-infected animals (p < 0.05). Gait analyses disclosed greater gait width with increased variation in FIV-infected animals (p < 0.05). Maze performance showed that FIV-infected animals were slower and made more navigational errors than mock-infected animals (p < 0.05). In the object memory test, the FIV-infected group exhibited fewer successful steps with more trajectory errors compared with the mock-infected group (p < 0.05). Performance on the gait, maze, and object memory tests was inversely correlated with F4/80 and CD3 epsilon expression (p < 0.05) and with viral burden in parietal cortex (p < 0.05). Amino acid analysis in cortex showed that D-serine levels were reduced in FIV-infected animals, which was accompanied by diminished kainate and AMPA receptor subunit expression (p < 0.05). The neurobehavioral findings in FIV-infected animals were associated with increased gliosis and reduced cortical neuronal counts (p < 0.05). The present studies indicated that specific motor and neurocognitive abilities were impaired in FIV infection and that these effects were closely coupled with viral burden, neuroinflammation, and neuronal loss.

Cognitive neuropsychology of HIV-associated neurocognitive disorders

Advances in the treatment of the human immunodeficiency virus (HIV) have dramatically improved survival rates over the past 10 years, but HIV-associated neurocognitive disorders (HAND) remain highly prevalent and continue to represent a significant public health problem. This review provides an update on the nature, extent, and diagnosis of HAND. Particular emphasis is placed on critically evaluating research within the realm of cognitive neuropsychology that aims to elucidate the component processes of HAND across the domains of executive functions, motor skills, speeded information processing, episodic memory, attention/working memory, language, and visuoperception. In addition to clarifying the cognitive mechanisms of HAND (e.g., impaired cognitive control), the cognitive neuropsychology approach may enhance the ecological validity of neuroAIDS research and inform the development of much needed novel, targeted cognitive and behavioral therapies.

The neuropsychology of cocaine addiction: recent cocaine use masks impairment

Individuals with current cocaine use disorders (CUD) form a heterogeneous group, making sensitive neuropsychological (NP) comparisons with healthy individuals difficult. The current study examined the effects on NP functioning of four factors that commonly vary among CUD: urine status for cocaine (positive vs negative on study day), cigarette smoking, alcohol consumption, and dysphoria. Sixty-four cocaine abusers were matched to healthy comparison subjects on gender and race; the groups also did not differ in measures of general intellectual functioning. All subjects were administered an extensive NP battery measuring attention, executive function, memory, facial and emotion recognition, and motor function. Compared with healthy control subjects, CUD exhibited performance deficits on tasks of attention, executive function, and verbal memory (within one standard deviation of controls). Although CUD with positive urine status, who had higher frequency and more recent cocaine use, reported greater symptoms of dysphoria, these cognitive deficits were most pronounced in the CUD with negative urine status. Cigarette smoking, frequency of alcohol consumption, and dysphoria did not alter these results. The current findings replicate a previously reported statistically significant, but relatively mild NP impairment in CUD as compared with matched healthy control individuals and further suggest that frequent/recent cocaine use [corrected] may mask underlying cognitive (but not mood) disturbances. These results call for development of pharmacological agents targeted to enhance cognition, without negatively impacting mood in individuals addicted to cocaine.

Effects of antiretroviral therapy on cognitive impairment

Since the introduction of combination antiretroviral therapy, the manifestations of HIV-associated central nervous system (CNS) involvement have generally become less severe and more manageable. Patients initiating antiretroviral therapy have demonstrated improvement in cognitive functioning. Reduction of viral burden has been correlated with improved CNS functioning. Recent studies have focused on the importance of CNS-penetrating antiretroviral regimens to target active replication in this protected compartment. There were initial conflicting reports of whether CNS-penetrating antiretrovirals improved cognitive functioning, with more evidence supporting the importance of CNS penetration in reducing viral burden and improving cognitive outcomes. Cognitive loss remains a feature of HIV infection, and some patients still suffer from incident or progressing cognitive and motor dysfunction even on combination therapy. Because the virus enters the CNS within days of initial infection, latent infection may be chipping away at the brain during the long asymptomatic period in HIV. When to start antiretrovirals for the maximum cognitive benefit remains to be determined.

NeuroAIDS: characteristics and diagnosis of the neurological complications of AIDS

The neurological complications of AIDS (NeuroAIDS) include neurocognitive impairment and HIV-associated dementia (HAD; also known as AIDS dementia and HIV encephalopathy). HAD is the most significant and devastating central nervous system (CNS) complications associated with HIV infection. Despite recent advances in our knowledge of the clinical features, pathogenesis, and neurobiological aspects of HAD, it remains a formidable scientific and therapeutic challenge. An understanding of the mechanisms of HIV neuroinvasion, CNS proliferation, and HAD pathogenesis provide a basis for the interpretation of the diagnostic features of HAD and its milder form, HIV-associated minor cognitive/motor disorder (MCMD). Current diagnostic strategies are associated with significant limitations, but it is hoped that the use of biomarkers may assist researchers and clinicians in predicting the onset of the disease process and in evaluating the effects of new therapies.