HIV-associated neurocognitive disease continues in the antiretroviral era

Despite the ability to suppress viral replication with antiretroviral therapy, HIV-associated neurocognitive disturbances can still be detected in nearly half of patients. Neurologic dysfunction before initiating or in the absence of antiretroviral treatment is primarily the result of neuronal dysfunction or loss from direct viral effects, whereas that in patients receiving antiretroviral therapy appears to be associated at least in part with inflammation driven by chronic low-level infection. Contributing factors may include genetic differences in HIV and human hosts and aging of patients. This article summarizes a presentation on HIV-associated neurocognitive disorder made by David B. Clifford, MD, at an International AIDS Society-USA Continuing Medical Education course in New York in October 2007.

Updated research nosology for HIV-associated neurocognitive disorders

In 1991, the AIDS Task Force of the American Academy of Neurology published nomenclature and research case definitions to guide the diagnosis of neurologic manifestations of HIV-1 infection. Now, 16 years later, the National Institute of Mental Health and the National Institute of Neurological Diseases and Stroke have charged a working group to critically review the adequacy and utility of these definitional criteria and to identify aspects that require updating. This report represents a majority view, and unanimity was not reached on all points. It reviews our collective experience with HIV-associated neurocognitive disorders (HAND), particularly since the advent of highly active antiretroviral treatment, and their definitional criteria; discusses the impact of comorbidities; and suggests inclusion of the term asymptomatic neurocognitive impairment to categorize individuals with subclinical impairment. An algorithm is proposed to assist in standardized diagnostic classification of HAND.

Impact of an HPV diagnosis on the quality of life in young women

OBJECTIVE

To evaluate the impact of the communication of an HPV diagnosis on the cognitive-behavioural aspect, emotional experiences, psychic-physical well-being, and psychosexual sphere in young women between the ages of 20 and 45.

METHOD

During the period between February 2006 and March 2007, at the U.O. Department of Obstetrics and Gynecology of the ULSS 13 of Mirano (VE), we distributed three self-evaluating questionnaires (the CBA-20, the SAT-P, and the BISF-W) to 36 women who had been diagnosed with an HPV infection and 36 women who had never been diagnosed with HPV.

RESULTS

36% of the experimental group reacted to the diagnosis with fear and 29% reacted with anxiety, while in only 3% of the cases did the women react with anger. Significant differences emerged in two samples regarding state anxiety and obsessive and compulsive aspects, while there were no significant differences between the two groups regarding the subjective satisfaction with life quality and sexual function. A significant positive correlation was found between the sum of anxiety and fear expressed at the time of the diagnosis and the trait anxiety reported in the Cognitive Behavioural Assessment 2.0.

CONCLUSIONS

The results indicate that the prevalent emotions felt at the time of the diagnosis are fear and anxiety. The persons who were diagnosed with an HPV infection resulted as having higher levels of trait anxiety, obsessions, compulsions, and above all, behaviours and worries related to hygiene and improbable infections.

The prevalence and incidence of neurocognitive impairment in the HAART era

OBJECTIVES

HAART suppresses HIV viral replication and restores immune function. The effects of HAART on neurological disease are less well understood. The aim of this study was to assess the prevalence and incidence of neurocognitive impairment in individuals who initiated HAART as part of an AIDS clinical trial.

DESIGN

A prospective cohort study of HIV-positive patients enrolled in randomized antiretroviral trials, the AIDS Clinical Trials Group (ACTG) Longitudinal Linked Randomized Trials (ALLRT) study.

METHODS

We examined the association between baseline and demographic characteristics and neurocognitive impairment among 1160 subjects enrolled in the ALLRT study.

RESULTS

A history of immunosuppression (nadir CD4 cell count < 200 cells/microl) was associated with an increase in prevalent neurocognitive impairment. There were no significant virological and immunological predictors of incident neurocognitive impairment. Current immune status (low CD4 cell count) was associated with sustained prevalent impairment.

CONCLUSION

The association of previous advanced immunosuppression with prevalent and sustained impairment suggests that there is a non-reversible component of neural injury that tracks with a history of disease progression. The association of sustained impairment with worse current immune status (low CD4 cell count) suggests that restoring immunocompetence increases the likelihood of neurocognitive recovery. Finally, the lack of association between incident neurocognitive impairment and virological and immunological indicators implies that neural injury continues in some patients regardless of the success of antiretroviral therapy on these laboratory measures.

The prevalence and incidence of neurocognitive impairment in the HAART era

OBJECTIVES

HAART suppresses HIV viral replication and restores immune function. The effects of HAART on neurological disease are less well understood. The aim of this study was to assess the prevalence and incidence of neurocognitive impairment in individuals who initiated HAART as part of an AIDS clinical trial.

DESIGN

A prospective cohort study of HIV-positive patients enrolled in randomized antiretroviral trials, the AIDS Clinical Trials Group (ACTG) Longitudinal Linked Randomized Trials (ALLRT) study.

METHODS

We examined the association between baseline and demographic characteristics and neurocognitive impairment among 1160 subjects enrolled in the ALLRT study.

RESULTS

A history of immunosuppression (nadir CD4 cell count < 200 cells/microl) was associated with an increase in prevalent neurocognitive impairment. There were no significant virological and immunological predictors of incident neurocognitive impairment. Current immune status (low CD4 cell count) was associated with sustained prevalent impairment.

CONCLUSION

The association of previous advanced immunosuppression with prevalent and sustained impairment suggests that there is a non-reversible component of neural injury that tracks with a history of disease progression. The association of sustained impairment with worse current immune status (low CD4 cell count) suggests that restoring immunocompetence increases the likelihood of neurocognitive recovery. Finally, the lack of association between incident neurocognitive impairment and virological and immunological indicators implies that neural injury continues in some patients regardless of the success of antiretroviral therapy on these laboratory measures.

Neuropsychological deficits in human immunodeficiency virus type 1 clade C-seropositive adults from South India

Most studies of cognitive functioning in human immunodeficiency virus type 1 (HIV-1)-seropositive (HIV-1+) subjects have been done in the United States and Europe, where clade B infections predominate. However, in other parts of the world such as South India, where clade C HIV is most common, the prevalence of HIV-1 is increasing. Standardized neuropsychological tests were used to assess cognitive functioning in a sample of 119 adults infected with clade C HIV-1 who were not on antiretroviral medications. The subjects did not have neurological or psychiatric illness and were functioning adequately. Neuropsychological test performance was compared with gender-, age-, and education-matched normative data derived from a sample of 540 healthy volunteers and a matched cohort of 126 healthy, HIV-1-seronegative individuals. Among the seropositive subjects, 60.5% had mild to moderate cognitive deficits characterized by deficits in the domains of fluency, working memory, and learning and memory. None of the subjects had severe cognitive deficits. The HIV-1+ sample was classified into groups according to the level of immune suppression as defined by CD4 count (< 200, 201-499, and > 500 cells/mm3) and viral load (< 5000, 5001-30,000, 30,001-99,999, 100,000-1,000,000, and > 1,000,001 copies). Although the most immunosuppressed group (CD4 count < 200 cells/mm3 or viral load > 1,000,001 copies) was small, their rate of impairment in visual working memory was greater when compared to groups with better immune functioning. Mild to moderate cognitive deficits can be identified on standardized neuropsychological tests in clade C-infected HIV-1+ adults who do not have any clinically identifiable functional impairment. The prevalence of cognitive deficits is similar to that reported in antiretroviral treatment-naïve individuals infected with clade B virus in the western world.

Neuropsychological test profile differences between young and old human immunodeficiency virus-positive individuals

Human immunodeficiency virus (HIV) dementia remains as an important cause of neurological morbidity among HIV-seropositive (HIV+) individuals. Differences in the neuropsychological profiles between older and younger HIV+ individuals have not been examined extensively. The objective of this study was to examine the neuropsychological test performance between old and young HIV+ individuals (a) with and without cognitive impairment (total cohort) and (b) with dementia. One hundred thirty-three older (age >or= 50 years) HIV+ individuals and 121 younger (age 20 to 39 years) HIV+ individuals were evaluated with a standardized neuropsychological test battery. Differences between age groups in the mean z score for each neuropsychological test were determined. The older HIV+ (total) cohort had greater impairment in tests of verbal memory (P = .006), visual memory (P < .002), verbal fluency (P = .001), and psychomotor speed (P < .001) compared to the young HIV+ (total) cohort. After adjusting for differences in education, older HIV+ patients with dementia (n = 31) had a greater deficit in the Trail Making test Part B (P = 0.02) compared to younger HIV+ patients with dementia (n = 15). Age was associated with lower performance in tests of memory, executive functioning, and motor performance in older HIV+ individuals with and without cognitive impairment (total cohort), compared to younger HIV+ individuals. Among HIV+ patients with dementia, age may be associated with greater impairment in a test of executive functioning. These differences could be a result of advanced age itself or age-associated comorbidities such as coexisting cerebrovascular or neurodegenerative disease.

Neuropsychological sequelae of acute-onset sporadic viral encephalitis

Acute encephalitis is an inflammation of the brain parenchyma. In the USA, by estimation, 20,000 cases occur every year. A variety of cognitive deficits may persist after the acute stage, and they are often the sole cause of disability. Recent literature demonstrates the heterogeneity of both amnestic disorders and the outcome following encephalitis. Herpes simplex virus is the most commonly recognised single aetiology of sporadic encephalitis and it may be the cause of the most severe symptoms. Antiviral medication, however, seems to have improved the cognitive outcome when compared to the historical, untreated cases. The cognitive sequelae following herpes simplex virus encephalitis (HSVE) are best known and most commonly described, e.g., in textbooks, but they do not represent the typical symptomatology of encephalitis in general. Much less is unfortunately known about other types of encephalitis, those that account perhaps up to 80% of all cases, where both mild and severe defects have been observed. This article summarises the current knowledge.

Pre- and post-encephalitic neuropsychological profile of a 7-year-old girl

Our understanding of the neuropsychological effects of encephalitis has largely come from studies in which the level of premorbid functioning is estimated. Moreover, data on the neuropsychological effects of encephalitogenic pathogens other than the herpes simplex virus (HSV) are scant. We present the case of a 7-year-old girl who had intellectual and language assessment seven months prior to the onset of non-HSV encephalitis (possible aetiology: Mycoplasma pneumoniae), and again post-encephalitis. MRI post-illness demonstrated basal frontal, temporal and (limited) parietal damage. Details of speech, psychological and neuropsychological assessments were also documented. Pervasive changes were apparent in the domains of personality, behaviour, emotionality, attention, executive function, speech, language and memory. The patient's profile appears to differ most from that seen following typical HSV encephalitis with respect to marked executive and attentional difficulties. Her deficits appear to reflect both her acute basal brain injury and more diffuse insult, probably caused by postinfectious encephalitis.

HIV-1 RNA concentration and cognitive performance in a cohort of HIV-positive people

OBJECTIVE

To determine whether higher viral concentrations in the cerebrospinal fluid (CSF) and/or peripheral blood were associated with greater severity of cognitive impairment in HIV-1-seropositive subjects with cognitive-motor impairment.

METHODS

Cognitive performance measurements and viral load were obtained from HIV-1-seropositive individuals with cognitive-motor impairment entering a clinical trial before the introduction of highly active antiretroviral therapy (HAART). CSF viral load (UltraSensitive Roche HIV-1 Monitor test with detection limit of 50 copies/ml) was available from 179 patients, and peripheral (plasma or serum) viral load from 111 patients. Of these patients, 62% met the 1993 Centers for Disease Control (CDC) criteria for AIDS, and 19% had clinically significant cognitive impairment (i.e., global deficit score > or = 0.5). Possible associations between viral load and cognitive scores were examined with general linear regression models with and without adjustment for age, education, study site, antiretroviral use, CD4 cell count, and CDC stage.

RESULTS

The mean CSF viral load was 2.83 log(10)/ml +/- 0.94 (SD) (undetectable in 19.5%). Mean peripheral viral load was 4.11 log(10)/ml +/- 0.90 (SD). No statistically significant associations emerged between either CSF or peripheral viral load and the global deficit score, or any of the seven cognitive domain deficit scores.

CONCLUSIONS

Among these HIV-1-sero-positive individuals with mainly minor HIV-1-associated cognitive deficits and not receiving HAART, no association between CSF or blood concentration of HIV-1 RNA and cognitive performance could be found. These results suggest that the severity of HIV-1-associated cognitive impairment is not directly related to concurrent viral concentration in the CSF or the peripheral blood.

Neurological evaluation of untreated human immunodeficiency virus infected adults in Ethiopia

Human immunodeficiency virus (HIV) has been implicated in neurological complications in developed countries. Developing countries have different viral clades and potentially different genetic and social risks for these complications. Baseline neurological performance measures associated with HIV infection have rarely been available from developing countries. The authors carried our a cross-sectional neurological evaluation of a cohort of community-dwelling treatment-naïve HIV-infected patients and similar control subjects from the same communities in Ethiopia. Blinded evaluation using standardized structured questionnaires and a neurological examination was performed by neurologists and treating physicians trained by an HIV neurology specialist. Quantitative performance measures for cognitive and motor function were employed. Data were analyzed with descriptive statistical methods, standard contingency table methods, and nonparametric methods. HIV-positive and control groups were similar by age, gender, and job site. Participants included 73 HIV-positive and 87 HIV-negative controls. Fingertapping speed in the dominant hand was more poorly performed in HIV positives than negatives (P = .01) and was significantly associated with HIV viral load levels (P = .03). Other quantitative neuropsychiatric tests including timed gait, grooved pegboard, task learning, and animal naming did not show significant differences between the two groups. The overall prevalence of central nervous system (CNS) and/or peripheral nervous system (PNS) disease did not significantly differ in the two populations. HIV patients had slowed fingertapping speed correlating with viral load. Other measures of CNS and/or peripheral nervous performance did not differ from controls. The unanticipated minor evidence of HIV-associated neurocognitive and peripheral nerve deficits in this untreated HIV-positive population invite further investigation.

Cognitive reserve and neuropsychological functioning in patients infected with hepatitis C

This study evaluated the influence of cognitive reserve on neuropsychological test performance in 198 patients infected with the hepatitis C virus. IQ scores, educational level, and occupational rating were combined to calculate a Cognitive Reserve Score (CRS) for each patient. Similar to studies of infection with the human immunodeficiency virus, there was a significantly increased risk of impairment in neuropsychological test performance in individuals with lower CRSs. It is important to account for CRS when assessing cognitive findings in large-scale clinical trials.

The long-term outcomes of human West Nile virus infection

Since its introduction to North America in 1999, human infection with West Nile virus (WNV) has resulted in considerable acute morbidity and mortality. Although the ongoing epidemic has resulted in a great increase in our understanding of the acute clinical features of human illness and helped to define associated clinical syndromes, far less is known about potential long-term clinical and functional sequelae. Several recent assessments, however, suggest that patients--even those with apparently mild cases of acute disease--frequently have subjective, somatic complaints following WNV infection. Persistent movement disorders, cognitive complaints, and functional disability may occur after West Nile neuroinvasive disease. West Nile poliomyelitis may result in limb weakness and ongoing morbidity that is likely to be long term. Although further assessment is needed, the long-term neurological and functional sequelae of WNV infection are likely to represent a considerable source of morbidity in patients long after their recovery from acute illness.

Dementia and neurocognitive disorders due to HIV-1 infection

Human immunodeficiency virus-type 1 (HIV-l) infection is the most common preventable and treatable cause of neurocognitive impairment in individuals under age 50 years. Although the incidence of HIV-associated dementia has decreased over the past few years due to combination antiretroviral therapy (cART), the prevalence of less severe HIV-associated neurocognitive impairment continues to increase. HIV-associated neurocognitive impairment is a significant burden to persons living with HIV infection, caregivers, and the health care system. Neurocognitive changes associated with HIV are typically subcortical, consisting of the triad of cognitive, behavior, and motor dysfunction. HIV-associated dementia and HIV-associated neurocognitive impairment are clinical diagnostic syndromes with neuropsychological performance testing, neuroimaging, and cerebral spinal fluid studies providing additional information. With the advent of more effective cART, the incidence of fatal opportunistic complications has dramatically diminished. Accordingly, the present review focuses on primary HIV-induced disease of the central nervous system, rather than its opportunistic complications.

[Neuropsychological impairment in human immunodeficiency virus-positive children]

INTRODUCTION

From human immunodeficiency virus (HIV)/AIDS epidemic onset in 1981 through 2003, 580,000 infants, children and adolescents died worldwide. Currently, between 2.1 and 2.9 million are estimated to live with HIV/AIDS. Here we review the main features of HIV/AIDS in infants, children and adolescents from a neuropsychological stance. Also, we review current neuropsychological tests for assessment of HIV/AIDS-associated neuropsychological impairment in infants, children and adolescents.

DEVELOPMENT

Most HIV-positive infants and children will die before adolescence. These children present both neurological and neuropsychological derangements with a variety of cognitive and motor deficits and important differences in their course. The main neurological condition related to HIV infection in childhood is HIV-associated progressive encephalopathy, which may be the initial presenting condition for AIDS in 18% of cases, affecting 30-60% of seropositive infants, children and adolescents at any time point of their disease. HIV-associated progressive encephalopathy causes neuropsychological deficits involving a wide variety of domains, such as speed and language, memory, learning, information processing and motor functioning. They may affect negatively children's normal development and school achievement.

CONCLUSIONS

It is crucial to determine how infection affects HIV-positive children and adolescents' development and to establish which interventions are more efficient to help them to be successful at school. Also, it is necessary to determine confounding variable role in HIV-positive infants, children and adolescents' cognitive development to determine direct and indirect HIV-infection effects on neuropsychological development.

Neuropsychological aspects of coinfection with HIV and hepatitis C virus

Infection with hepatitis C virus (HCV) is commonly seen in persons with human immunodeficiency virus (HIV) infection, because the viruses share risk factors for transmission; coinfection is a leading cause of morbidity and mortality among HIV-infected persons. Neuropsychological consequences of HIV infection are well established, and studies of HCV-infected persons have revealed neuropsychiatric dysfunction in this population as well. Investigators now are focusing on neuropsychological sequelae of coinfection with HIV and HCV, and preliminary results suggest that coinfection has a possible deleterious effect on global cognitive functioning consistent with frontal-subcortical dysfunction. Data on neuropsychiatric symptoms in coinfected persons are inconclusive at this time and are complicated by important differences in study populations (e.g., injection drug use and disease severity). This review summarizes what is known about neuropsychological aspects of monoinfection with HIV and HCV, as well as coinfection, discusses implications of these findings, and suggests future directions for this research area.

Prevalence of human immunodeficiency virus-associated cognitive impairment in a group of Hispanic women at risk for neurological impairment

Human immunodeficiency virus (HIV)-associated cognitive impairment, a significant cause of morbidity, affects up to 30% of HIV-infected people. Its prevalence doubled as patients began to live longer after the introduction of highly active retroviral therapy. Women are now one of the fastest growing groups with acquired immunodeficiency syndrome (AIDS) in the United States and Puerto Rico, but relatively little is known about the prevalence and characteristics of cognitive dysfunction in HIV-infected women. In this study the authors investigated its prevalence in a group of HIV-1-seropositive Hispanic women in Puerto Rico. Forty-nine women with a nadir CD4 cell count of < or = 500 cells/mm3 were enrolled. Cognitive impairment was defined according to the American Academy of Neurology criteria for HIV dementia as modified to identify an "asymptomatic cognitively impaired" group. Observed prevalence was compared with prevalence in other populations in United States, Europe, and Australia. Differences in clinical markers and neuropsychological test performance among the cohort stratified by cognitive impairment were tested. Cognitive impairment was observed in 77.6% (38/49) of cases; asymptomatic cognitive impairment in 32.7% (16/49); minor cognitive motor disorders in 16.3% (8/49); and HIV-associated dementia (HAD) in 28.6% (14/49). Cognitive impairment did not correlate with age, CD4 cell count, viral load, or treatment modality. The cross-sectional prevalence of HIV-associated cognitive impairment was 77.6% (28.6% for HAD). These findings should enhance awareness of the prevalence of HIV-associated cognitive impairment, both clinically apparent and "asymptomatic," in Hispanic women and lead to improvements in areas such as education and compliance and to reevaluation of treatment interventions.

NeuroAIDS in Brazil

Brazil has the largest number of HIV cases of any single country in Latin America - over 600,000. Recently, investigators have begun to characterize the extent of neurological morbidity due to HIV in this country. During 2005 and 2006, the U.S. National Institute of Mental Health cosponsored two meetings of experts aimed at summarizing existing knowledge of HIV and its neurological complications in Brazil. Topics addressed ranged from clinical neurobehavioral aspects to molecular biology. Experts attending the meeting considered fruitful directions for future research.

HPA axis activity and neuropathogenesis in HIV-1 clade C infection

A disturbance in the activity of the hypothalamic-pituitary-adrenal (HPA) axis has been reported among individuals with HIV-1 infection. However, these studies have been carried out in the West where the infecting clade is clade B. HIV-1 infection is rapidly spreading in various parts of South East Asia, including India, where the HIV-1 infecting clade is largely clade C. An investigation of HPA axis activity in this type of infection is warranted since there are many structural differences between clades B and C. This study was carried out to investigate whether HIV-1 infection clade C interferes with the functions of the hippocampus and thereby affects the HPA axis. We tested the hypothesis that when hippocampus activity is disturbed, it leads to the development of neuropathogenesis in HIV-1 C-clade infected individuals. This study included asymptomatic HIV-1 seropositive individuals (n=117) and, age-matched, HIV-1 seronegative controls (n=29). Neuroendocrine function of the HPA axis was evaluated using plasma levels of cortisol, ACTH, and DHEA-S, both in the morning (0800-1000 hr) and evening (2000-2200 hr). A significant elevation of cortisol levels during A.M. and P.M. hours was observed in HIV-1 infected individuals when compared to the controls. Interestingly, no significant change in ACTH level was observed in HIV-1 seropositive subjects, either during A.M or P.M. Elevated levels of cortisol in HIV-1 seropositive subjects appear to be independent of ACTH and may be the result of a defective negative feedback mechanism. On the other hand, a significant decrease in the plasma levels of DHEA-S was observed during A.M. and P.M. hours in HIV-1 infected individuals, leading to an increased cortisol to DHEA-S ratio. Since increased levels of cortisol and decreased levels of DHEA-S are related to the development of neuropathogenesis, it is hypothesized that a study of the development of neurocognitive deficits among HIV-1 seropositive individuals in India is warranted.

Intrathecal viral replication and cerebral deficits in different stages of human immunodeficiency virus disease

The objectives of this study is to clarify whether there are phases critical for the infection of the central nervous system (CNS) as defined by active viral replication in the cerebrospinal fluid (CSF) in human immunodeficiency virus (HIV) infection. One hundred and nine HIV-1-positive homo- and bisexual patients in early and late disease stages with or without highly active antiretroviral therapy (HAART) were included in the cross-sectional, diagnostic (phase I) multicenter study. No patients had any overt neurological deficits; all underwent venous and lumbar puncture as well as neuropsychological testing. In untreated early-stage patients, cerebrospinal fluid (CSF) viral load correlated with inflammatory parameters, but not significantly with neuropsychological abnormalities. CSF viral load and inflammatory reactions were suppressed in HAART-treated early-stage patients. In HAART-treated late-stage patients, there was a weak correlation between CSF viral load and CSF cell count as well as a moderate correlation with immune activation markers and with distinct cerebral deficits independent of CSF viral load. Seventeen of the 109 patients had higher CSF than plasma viral loads and marked inflammatory reactions and immune activation. In patients with greater plasma than CSF viral loads, the factors contributing to cerebral deficits still need to be identified. The results suggest not only that there is an early "set point" for CSF/central nervous system (CNS) infection, but also that there is a subgroup of patients in whom intrathecal viral replication correlates with cerebral deficits. Lumbar puncture should be performed in all positive patients to identify members of this subgroup and to ascertain what characteristic factors they have in common in order to improve therapy.

Chronic cocaine exposure in the SCID mouse model of HIV encephalitis

Clinical and preclinical evidence suggests that cocaine exposure hastens progression of the HIV disease process. An established active, euphoric dose of cocaine (20 mg/kg) was administered to SCID mice according to a regimen consistent with exposure to the drug by cocaine-abusing HIV-infected patients to determine the effects of cocaine on four previously established pathological characteristics of HIV encephalitis: cognitive deficits, fatigue, astrogliosis, and microgliosis. Mice were intracranially inoculated with either HIV-infected, or uninfected macrophages and then injected with either cocaine or saline in a 2 (Infection)x2 (Cocaine) factorial design. Cognition was assessed by acquisition and retention of a spatially cued learning task. Fatigue was assessed by monitoring motor activity following a 2 min forced swim. Mice were then sacrificed to determine the extent of astrogliosis and microgliosis in the four groups. Results indicated that in comparison to uninfected controls, HIV positive mice had increased astrogliosis and microgliosis, cognitive deficits, and recovered more slowly from fatigue. However, despite evidence that the cocaine exposure regimen activated the central nervous system and had long-term CNS effects, the drug did not alter the behavioral or the neuropathological deficits noted in HIV-infected SCID mice.

Promoting successful cognitive aging in adults with HIV: strategies for intervention

Aging individuals with HIV may be at risk for developing more age-related cognitive decline, mild cognitive impairment, or even dementia. The incidence of HIV-related dementia was reduced sharply with the introduction of HAART. Positive mediators, such as good nutrition or cognitive remediation therapy, can potentially mitigate some of the negative cognitive consequences of aging with HIV.