Cognitive decline in patients with symptomatic HIV-1 infection. No decline in asymptomatic infection

Cognitive function in patients with newly diagnosed HIV infection in a tertiary health facility in south - west Nigeria: Assessment using computer-assisted neuropsychological test battery

INTRODUCTION

Cognitive dysfunction is common among patients with human immunodeficiency virus (HIV) infection however there are few reports from sub-Saharan Africa.

METHODS

We studied fifty seropositive patients with human immunodeficiency virus (HIV) infection along with fifty matched seronegative control. Medical history taking and general physical and neurological examinations were done for all study participants. Laboratory evaluations and chest X-ray were done for all the patients. The cognitive function was done with the aid of 'Fepsy' automated test battery for all the study participants. The data was analyzed with statistical package for social sciences software version 21.0 (SPSS Chicago IL).

RESULT

About 70% of the HIV patients were in advanced disease stage. The auditory and visual reaction times, binary choice reaction times, and computerized visual scanning task time were more prolonged in the HIV group (p < 0.05). There were also increased memory accuracy and binary choice task accuracy in the HIV group (p < 0.05). However the vigilance task performance was similar between the two groups (p > 0.05). Among the patients with HIV infection, the presence of anemia and central nervous system toxoplasmosis infection was associated with prolonged auditory and visual reaction times.

CONCLUSION

There was a high rate of cognitive dysfunction in patients with HIV infection in this study.

Three-decade neurological and neurocognitive follow-up of HIV-1-infected patients on best-available antiretroviral therapy in Finland

OBJECTIVES

Is it possible to live without neurocognitive or neurological symptoms after being infected with HIV for a very long time? These study patients with decades-long HIV infection in Finland were observed in this follow-up study during three time periods: 1986-1990, in 1997 and in 2013.

SETTING

Patients from greater Helsinki area were selected from outpatient's unit of infectious diseases.

PARTICIPANTS

The study included 80 HIV patients. Patients with heavy alcohol consumption, central nervous system disorder or psychiatric disease were excluded.

PRIMARY AND SECONDARY OUTCOME MEASURES

The patients underwent neurological and neuropsychological examinations, MRI of the brain and laboratory tests, including blood CD4 cells and plasma HIV-1 RNA. Neuropsychological examination included several measures: subtests of Wechsler Adult Intelligence Scale, Wechsler Memory Scale-Revised, list learning, Stroop and Trail-Making-B test. The Beck Depression Inventory and Fatigue Severity Scale were also carried out. The obtained data from the three time periods were compared with each other.

RESULTS

Owing to high mortality among the original 80 patients, eventually, 17 participated in all three examinations performed between 1986 and 2013. The time from the HIV diagnosis was 27 (23-30) years. Blood CD4 cells at the diagnosis were 610 (29-870) cells/mm(3), and the nadir CD4 168 (4-408) cells/mm(3). The time on combined antiretroviral treatment was 13 (5-17) years. 9 patients suffered from fatigue, 5 had polyneuropathy and 3 had lacunar cerebral infarcts. There was a subtle increase of brain atrophy in 2 patients. Mild depressive symptoms were common. The neuropsychological follow-up showed typical age-related cognitive changes. No HIV-associated dementia features were detected.

CONCLUSIONS

Polyneuropathy, fatigue and mild depression were common, but more severe neurological abnormalities were absent. These long-term surviving HIV-seropositive patients, while on best-available treatment, showed no evidence of HIV-associated neurocognitive disorder in neuropsychological and neuroradiological evaluations.

Declined neural efficiency in cognitively stable human immunodeficiency virus patients

OBJECTIVE

To determine whether brain activation changes in clinically and neurocognitively normal human immunodeficiency virus (HIV)-infected and in HIV-seronegative control (SN) participants over a 1-year period.

METHODS

Functional magnetic resonance imaging (fMRI) was performed in 32 SN and 31 HIV patients (all with stable combination antiretroviral treatment) at baseline and after 1 year. Each participant performed a set of visual attention tasks with increasing attentional load (from tracking two, three, or four balls). All HIV and SN participants had normal neuropsychological function at both examinations.

RESULTS

Over 1 year, HIV patients showed no change in their neurocognitive status or in task performance during fMRI. However, HIV patients showed significant 1-year increases in fMRI signals in the prefrontal and posterior parietal cortices for the more difficult tasks, whereas SN control participants showed only decreases in brain activation in these regions. This resulted in significant interactions between HIV status and time of study in left insula, left parietal, left temporal, and several frontal regions (left and right middle frontal gyrus, and anterior cingulate).

INTERPRETATION

Because fMRI task performance remained unchanged in both groups, the HIV patients appeared to maintain performance by increasing usage of the attention network, whereas the control participants reduced usage of the attention network after 1 year. These findings suggest improved efficiency or a practice effect in the SN participants but declined efficiency of the neural substrate in HIV patients, possibly because of ongoing brain injury associated with the HIV infection, despite their apparent stable clinical course.

Action (verb) generation in HIV-1 infection

It has been proposed that verb generation is primarily associated with left fronto-basal ganglia circuits, whereas the generation of nouns is principally mediated by dominant left temporo-parietal networks. Consistent with this premise, action (verb) fluency - a verbal fluency task requiring the spontaneous generation of verbs - has shown greater sensitivity to frontal-basal ganglia pathophysiology (e.g., dementia in Parkinson's disease (PDD)) than noun fluency. The present study examined action and noun fluency in persons with HIV-1 infection-a disease known to be associated with a frontal-basal ganglia circuit neuropathogenesis. Action and noun ("animals") verbal fluency protocols were administered to 97 persons with HIV-1 infection and 20 demographically comparable healthy comparison (HC) subjects. A significant interaction emerged between verbal fluency task and HIV-1 serostatus such that the HIV+ group generated significantly fewer actions (verbs) relative to the HC sample. Findings indicate that persons infected with HIV-1 experience difficulty rapidly generating verbs, but not nouns from semantic memory. Considering the prominent frontal-basal ganglia circuit neuropathophysiology of HIV-1 infection, these data are consistent with the hypothesized dissociation between noun and verb generation as pertains to generative fluency.

Relationships between cognition and structural neuroimaging findings in adults with human immunodeficiency virus type-1

Infection of the central nervous system with human immunodeficiency virus type-1 (HIV) is associated with cognitive impairments that range from mild cognitive and motor difficulties to dementia. Structural neuroimaging abnormalities are also common in HIV-infected patients both with and without cognitive disturbances. The most common abnormalities include high signal intensities in the white matter and atrophy. Research over the past 12 years has helped define the relationship between these neuroimaging abnormalities and the manifestation of cognitive disturbance in HIV. In the present paper, we provide a synopsis of these studies and report the current state of the literature. Our review revealed that atrophy of the caudate nucleus is most consistently associated with cognitive impairment in HIV. The current literature does not support a strong relationship between cortical atrophy or white matter abnormalities and cognitive dysfunction in this population, though methodological issues may have influenced the results. Suggestions for study design and new research directions are provided.

Predictors of perception of cognitive functioning in HIV/AIDS

This is a descriptive, correlational study of the predictors of perceived cognitive functioning. The convenience sample of 728 nonhospitalized persons receiving health care for HIV/AIDS was recruited from seven sites in the United States. All measures were self-reported. Self-perception of cognitive functioning, the dependent variable, was composed of three items from the Medical Outcomes Study HIV scale: thinking, attention, and forgetfulness. Data related to age, gender, ethnicity, education, injection drug use, CD4 count, and length of time known to be HIV-positive were collected on a demographic questionnaire. The scale from the Sign and Symptom Checklist for Persons with HIV Disease was used to measure self-reported symptoms. Data were analyzed using hierarchical multiple regression analysis. Predictors of perception of cognitive functioning explained a total of 36.3% of the variance. Four blocks--person variables (1.5%) (age, gender, education, history of injection drug use), disease status (2.3%), symptom status (26.5%), and functional status (5.4%)--significantly contributed statistically to the total variance. Among those individuals who completed the questions related to depression (n = 450), 28% of the variance in cognitive functioning was explained by this variable. The findings in this multi-site study indicate that symptom status explained the largest amount of variance in perceived cognitive functioning. Early identification of cognitive impairment can result in appropriate clinical interventions in remediable conditions and in the improvement of quality of life.