Summary Cross-sectional studies show that around half of individuals infected with HIV-1 have some degree of cognitive impairment despite the use of antiretroviral drugs. However, prevalence ...estimates vary depending on the population and methods used to assess cognitive impairment. Whether asymptomatic patients would benefit from routine screening for cognitive difficulties is unclear and the appropriate screening method and subsequent management is the subject of debate. In some patients, HIV-1 RNA can be found at higher concentrations in CSF than in blood, which potentially results from the poor distribution of antiretroviral drugs into the CNS. However, the clinical relevance of so-called CSF viral escape is not well understood. The extent to which antiretroviral drug distribution and toxicity in the CNS affect clinical decision making is also debated.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
INTRODUCTION:Psychiatric symptoms (PSs) are reported to occur frequently in people living with HIV and may be associated with specific antiretrovirals. We analyzed PSs observed with dolutegravir ...(DTG) and other frequently prescribed anchor drugs.
METHODS:Selected PSs (insomnia, anxiety, depression, and suicidality) occurring in HIV-positive patients during DTG treatment across 5 randomized clinical trials (3 double-blind), in the Observational Pharmaco-Epidemiology Research & Analysis (OPERA) cohort, and among cases spontaneously reported to ViiV Healthcare were analyzed.
RESULTS:In clinical trials, PSs were reported at low and similar rates in patients receiving DTG or comparators atazanavir, darunavir, efavirenz, or raltegravir (RAL). Insomnia was most commonly reported. The highest rates were observed in SINGLE (DTG 17%, efavirenz 12%), with consistently lower rates in the other trials (DTG3%–8% versus comparator3%–7%). More efavirenz-treated patients withdrew because of PSs than patients treated with other anchor drugs. In OPERA, history of PSs at baseline was lowest in efavirenz-treated patients compared with patients treated with DTG, RAL, or darunavir. Despite baseline differences, prevalence and incidence during treatment were similar across the 4 anchor drugs. Withdrawal rates for PSs were lowest for DTG (0%–0.6%) and highest for RAL (0%–2.5%). Spontaneously reported events were similar in nature to clinical trial data.
CONCLUSIONS:Analysis of 3 different data sources shows that, similar to other frequently prescribed anchor drugs to treat HIV infection, PSs are also reported in DTG-treated patients. These events are reported with low frequency and rarely necessitate DTG discontinuation.
Neuroinflammation plays an important role in HIV-associated neurological disorders; however, its role prior to the onset of symptomatic disease is unclear. We imaged microglial activation, the ...hallmark of neuroinflammation, in asymptomatic HIV-infected patients on effective combination ART.
Seven neurologically and cognitively asymptomatic adults with chronic HIV-infection and nine healthy volunteers were investigated with 11C-PK11195 PET, a marker of translocator protein (TSPO) expressed by activated microglia. In the HIV-infected patients, cognitive speed, accuracy and executive function were also assessed. Between-group differences in 11C-PK11195 binding potential were localized throughout the brain with statistical parametric mapping (SPM) and associations between levels of 11C-PK11195 binding and cognitive performance were interrogated using linear regression modelling.
In HIV-infected patients, Statistical parametric mapping detected clusters of significantly increased 11C-PK11195 binding in corpus callosum (P = 0.001), anterior cingulate (P = 0.001), posterior cingulate (P = 0.008) and temporal (P = 0.026) and frontal (P = 0.038) areas. Cognitive functions were intact in the HIV group, however, a significant association between greater 11C-PK11195 binding and poorer executive function performance was observed in the anterior cingulate (P = 0.031), corpus callosum and posterior cingulate (P = 0.001).
Despite effective control of HIV infection, neuroinflammation, as evidenced by the presence of focal cortical areas of activated microglia, occurs in asymptomatic HIV-infected patients and levels correlate with poorer executive performance. Further studies are needed to establish whether detection of activated microglia in HIV-infected patients represents a marker of future neurocognitive decline.
ObjectiveTo assess the overall pooled correlation coefficient estimate between cerebrospinal fluid (CSF) and blood neurofilament light (NfL) protein.MethodsWe searched Medline, Embase and Web of ...Science for published articles, from their inception to 9 July 2019, according to Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines. Studies reporting the correlation between CSF and blood NfL in humans were included. We conducted a random-effects meta-analysis to calculate the overall pooled correlation coefficient estimate, accounting for correlation technique and assay used. Heterogeneity was assessed using the I2 statistic test. In sensitivity analyses, we calculated the pooled correlation coefficient estimate according to blood NfL assay: single-molecule array digital immunoassay (Simoa), electrochemiluminescence (ECL) assay or ELISA.ResultsData were extracted from 36 articles, including 3961 paired CSF and blood NfL samples. Overall, 26/36 studies measured blood NfL using Simoa, 8/36 ECL, 1/36 ELISA and 1 study reported all three assay results. The overall meta-analysis demonstrated that the pooled correlation coefficient estimate for CSF and blood NfL was r=0.72. Heterogeneity was significant: I2=83%, p<0.01. In sensitivity analyses, the pooled correlation coefficient was similar for studies measuring blood NfL using Simoa and ECL (r=0.69 and r=0.68, respectively) but weaker for ELISA (r=0.35).ConclusionModerate correlations are demonstrated between CSF and blood NfL, especially when blood NfL was measured using Simoa and ECL. Given its high analytical sensitivity, Simoa is the preferred assay for measuring NfL, especially at low or physiological concentrations, and this meta-analysis supports its use as the current most advanced surrogate measure of CSF NfL.PROSPERO registration numberCRD42019140469
The reported prevalence of cognitive impairment remains similar to that reported in the pre-antiretroviral therapy era. This may be partially artefactual due to the methods used to diagnose ...impairment. In this study, we evaluated the diagnostic performance of the HIV-associated neurocognitive disorder (Frascati criteria) and global deficit score (GDS) methods in comparison to a new, multivariate method of diagnosis.
Using a simulated 'normative' dataset informed by real-world cognitive data from the observational Pharmacokinetic and Clinical Observations in PeoPle Over fiftY (POPPY) cohort study, we evaluated the apparent prevalence of cognitive impairment using the Frascati and GDS definitions, as well as a novel multivariate method based on the Mahalanobis distance. We then quantified the diagnostic properties (including positive and negative predictive values and accuracy) of each method, using bootstrapping with 10,000 replicates, with a separate 'test' dataset to which a pre-defined proportion of 'impaired' individuals had been added.
The simulated normative dataset demonstrated that up to ~26% of a normative control population would be diagnosed with cognitive impairment with the Frascati criteria and ~20% with the GDS. In contrast, the multivariate Mahalanobis distance method identified impairment in ~5%. Using the test dataset, diagnostic accuracy 95% confidence intervals and positive predictive value (PPV) was best for the multivariate method vs. Frascati and GDS (accuracy: 92.8% 90.3-95.2% vs. 76.1% 72.1-80.0% and 80.6% 76.6-84.5% respectively; PPV: 61.2% 48.3-72.2% vs. 29.4% 22.2-36.8% and 33.9% 25.6-42.3% respectively). Increasing the a priori false positive rate for the multivariate Mahalanobis distance method from 5% to 15% resulted in an increase in sensitivity from 77.4% (64.5-89.4%) to 92.2% (83.3-100%) at a cost of specificity from 94.5% (92.8-95.2%) to 85.0% (81.2-88.5%).
Our simulations suggest that the commonly used diagnostic criteria of HIV-associated cognitive impairment label a significant proportion of a normative reference population as cognitively impaired, which will likely lead to a substantial over-estimate of the true proportion in a study population, due to their lower than expected specificity. These findings have important implications for clinical research regarding cognitive health in people living with HIV. More accurate methods of diagnosis should be implemented, with multivariate techniques offering a promising solution.
Full text
Available for:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Learning and memory are important for successful education and career progression. We assess these functions in young people (YP) with perinatal HIV (PHIV) (with or without a previous AIDS-defining ...illness) and a comparable group of HIV-negative YP. 234 PHIV and 68 HIV-negative YP completed 9 tests; 5 National Institutes of Health (NIH) Toolbox tests (2 executive function, 1 speed of information processing, 2 memory); 2 Hopkins Verbal Learning Test Revised (HVLT-R) (learning (L), delayed recall (R)), and 2 verbal application measures. Z-scores for each test were calculated using normative data and averaged by domain where appropriate. The effect of predictors on test scores in the three domains with the lowest z-scores were analysed using linear regression. 139(59%) and 48(71%) PHIV and HIV-negative YP were female, 202(86%) and 52(76%) Black, and median age was 19 17, 21 and 18 16, 21 years respectively. 55(24%) PHIV had a previous Center for Disease Control and Prevention (CDC) class C AIDS-defining diagnosis (PHIV/C). For HVLT-R, there was a trend towards PHIV/C YP having the lowest mean z-scores (L -1.5 (95% CI -1.8,-1.2), R -1.7 (-2.0,-1.4)) followed by PHIV without a CDC C diagnosis (L -1.3 (-1.4,-1.1), R -1.4 (-1.5,-1.2)) and then the HIV-negative group (L -1.0 (-1.3,-0.7), R -1.1 (-1.3,-0.8)); all were greater than 1 SD below the reference mean. The same trend was seen for verbal application measures; however, z-scores were within 1 SD below the reference mean. NIH Toolbox tests were similar for all groups. In multivariable analyses PHIV/C and Black ethnicity predicted lower HVLT-R scores. Black ethnicity also predicted lower executive function scores, however each year increase in age predicted higher scores. In conclusion, cognitive performance in verbal learning and recall fell below population normative scores, and was more pronounced in PHIV/C, supporting wider findings that earlier antiretroviral therapy initiation, before the occurrence of AIDS-defining conditions, may protect aspects of cognitive development.
Full text
Available for:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
We investigated the correlations and agreement between cognitive assessments made using a computerised (CogState™, six domains) and a standard pen-and-paper battery (five domains) in PWH and ...lifestyle-similar HIV-negative individuals. Demographically adjusted domain and global T-scores were obtained and used to define cognitive impairment according to the multivariate normative comparison (MNC) criteria. Correlations between T-scores and the agreement between the classifications of cognitive impairment obtained from the two batteries were assessed using the Spearman's rank correlation and Cohen's κ, respectively. The correlation between global T-scores from the two batteries was 0.52 (95% CI 0.44-0.60) in PWH and 0.45 (0.29-0.59) in controls (p = 0.38 for their difference). Correlations were generally stronger between domains within the same battery than between those from different batteries. The agreement between the two batteries in classifying individuals as cognitively impaired or not impaired was fair in PWH (κ = 0.24) and poor in HIV-negative individuals (κ = −0.02). The moderate correlation between overall cognitive function and the modest agreement between binary classifications of cognitive impairment obtained from two different batteries indicate the two batteries may assess slightly different components of cognition.
Full text
Available for:
DOBA, IJS, IZUM, KILJ, NUK, OILJ, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK, VSZLJ
The reported prevalence of cognitive impairment (CI) varies widely in cohorts of people living with HIV (PLWH); this may partly be due to the use of different diagnostic criteria. Agreement between ...diagnostic criteria of CI, the optimal definition to use, and associations with patient-reported cognitive symptoms have not been fully investigated.
Two hundred ninety PLWH aged >50 years and 97 matched negative controls completed a detailed assessment of cognitive function and three questions regarding cognitive symptoms. Age- and education-adjusted test scores (T-scores) determined if subjects met the following definitions of CI: Frascati, global deficit score (GDS) and the multivariate normative comparison (MNC) method.
PLWH were more likely than controls to meet each definition of CI (ORs were 2.17, 3.12 and 3.64 for Frascati, GDS and MNC, respectively). Agreement of MNC with Frascati and GDS was moderate (Cohen's k = 0.42 and 0.48, respectively), whereas that between Frascati and GDS was good (k = 0.74). A significant association was found between all the three criteria and reporting of memory loss but not with attention and reasoning problems. The 41 (14 %) PLWH meeting all the three criteria had the lowest median global T-score (36.9) and highest rate of symptom reporting (42 %).
Different CI criteria show fair diagnostic agreement, likely reflecting their ability to exclude CI in the same group of individuals. Given the lower overall cognitive performance and higher rates of symptom reporting in those meeting all three criteria of CI, further work assessing this as a definition of CI in PLWH is justified.
Full text
Available for:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The optimal vaccination strategy to boost responses in the context of pre-existing immune memory to the SARS-CoV-2 spike (S) glycoprotein is an important question for global public health. To address ...this, we explored the SARS-CoV-2-specific humoral and cellular immune responses to a novel self-amplifying RNA (saRNA) vaccine followed by a UK authorised mRNA vaccine (BNT162b2) in individuals with and without previous COVID-19, and compared these responses with those who received an authorised vaccine alone. 35 subjects receiving saRNA (saRNA group) as part of the COVAC1 clinical trial and an additional 40 participants receiving an authorised SARS-CoV-2 vaccine only (non-saRNA group) were recruited. Antibody responses were measured by ELISA and a pseudoneutralisation assay for wildtype, Delta and Omicron variants. Cellular responses were measured by IFN-ƴ ELISpot and an activation induced marker (AIM) assay. Approximately 50% in each group had previous COVID-19 prior to vaccination, confirmed by PCR or antibody positivity on ELISA. All of those who received saRNA subsequently received a full course of an authorised vaccine. The majority (83%) of those receiving saRNA who were COVID-19 naïve at baseline seroconverted following the second dose, and those with previous COVID-19 had an increase in antibody titres two weeks following saRNA vaccination (median 27-fold), however titres were lower when compared to mRNA vaccination. Two weeks following the 2nd authorised mRNA vaccine dose, binding and neutralising antibody titres were significantly higher in the saRNA participants with previous COVID-19, compared to non-saRNA, or COVID-19 naive saRNA participants. Cellular responses were again highest in this group, with a higher proportion of spike specific CD8+ than CD4+ T cells when compared to those receiving the mRNA vaccine only. These findings suggest an immunological benefit of increased antigen exposure, both from natural infection and vaccination, particularly evident in those receiving heterologous vaccination with saRNA and mRNA.
Full text
Available for:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
PDF
