Verbal list learning and memory profiles in HIV-infected adults, Alzheimer's disease, and Parkinson's disease: An evaluation of the "cortical hypothesis" of NeuroAIDS

HIV+ population is getting older because of progress in treatments. Yet, there are concerns that Older HIV+ individuals (OHIV+) may be more vulnerable for developing a "cortical" dementia such as Alzheimer Disease (AD). Our aim was to explore the hypothesis that the cognitive deficit extends to ''cortical'' functions in OHIV+ by comparing serial position effects (SPE) in different groups of participants affected by "cortical" or "subcortical" damage. We enrolled a total of 122 subjects: 22 OHIV+ (≥60 years of age), 31 Younger HIV+ (YHIV+) (<60 years of age), 18 participants with AD, 23 subjects with Parkinson Disease (PD), and 28 healthy subjects. All subjects performed verbal learning tasks (VLT) to explore SPE. Factorial analysis of covariance showed a significant effect of "group" (p < 0.001) and "task" (Primacy vs Recency) (p < 0.001), but no significant group*task (p = 0.257) interaction. Compared with healthy subjects (p = 0.003), AD had the most severe reduction of Primacy, confirming a primary "encoding deficit," while PD confirmed a "frontal pattern." OHIV+ showed a memory profile similar to that of PD with a worsening of the cognitive performance in comparison with YHIV+. In conclusion, we did not confirm the "cortical" hypothesis in OHIV+, at least in terms of learning and memory functions.

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

OBJECTIVE

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

METHOD

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

RESULTS

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

CONCLUSIONS

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

Baseline CD4(+) T-cell count and cardiovascular risk factors predict the evolution of cognitive performance during 2-year follow-up in HIV-infected patients

BACKGROUND

The aim of our study was to better understand the dynamics between cardiovascular risk factors and immunological parameters in the evolution of cognitive performance in HIV+ patients.

METHODS

We conducted a prospective longitudinal study, consecutively enrolling asymptomatic HIV+ subjects during routine outpatient visits at two clinical centres. At baseline and after 2 years, all patients underwent a comprehensive neuropsychological battery. Common carotid intima-media thickness (cIMT) was also measured.

RESULTS

A total of 150 patients completed the study (77% males, median age 46 years, 20% with past AIDS-defining events, 95% on cART, 88% with HIV-RNA<50 copies/ml). After a 2-year follow-up, there was no difference in the proportion of patients with cognitive impairment (32% versus 33% at baseline; P=1.00). However, a significantly worse memory performance was observed (z score mean change -0.51, sd 1.05; P=0.001). At multivariate analysis, baseline dyslipidaemia (OR 2.7, 95% CI 1.1, 7.1; P=0.037) showed a significant association with a higher risk of memory impairment at 2-year follow-up, while higher baseline CD4(+) T-cell count (OR 0.80 per 100 cells/μl higher; 95% CI 0.66, 0.97; P=0.026) was found to be a protective factor, adjusting for the presence of a memory impairment at baseline. When the analysis was restricted to patients who did not change antiretroviral therapy during the study period (n=109), baseline cIMT (OR 14.6 per 0.1 mm higher; 95% CI 1.1, 189.9; P=0.041) also emerged as an independent risk factor for memory impairment at 2-year follow-up.

CONCLUSIONS

Immunological parameters and cardiovascular risk factors are independently associated with the evolution of cognitive status in HIV+ patients.