10 research outputs found
Level of agreement between frequently used cardiovascular risk calculators in people living with HIV
Objectives
The aim of the study was to describe agreement between the QRISK2, Framingham and Data Collection on Adverse Events of Anti‐HIV Drugs (D:A:D) cardiovascular disease (CVD) risk calculators in a large UK study of people living with HIV (PLWH).
Methods
PLWH enrolled in the Pharmacokinetic and Clinical Observations in People over Fifty (POPPY) study without a prior CVD event were included in this study. QRISK2, Framingham CVD and the full and reduced D:A:D CVD scores were calculated; participants were stratified into ‘low’ ( 20%) categories for each. Agreement between scores was assessed using weighted kappas and Bland–Altman plots.
Results
The 730 included participants were predominantly male (636; 87.1%) and of white ethnicity (645; 88.5%), with a median age of 53 [interquartile range (IQR) 49–59] years. The median calculated 10‐year CVD risk was 11.9% (IQR 6.8–18.4%), 8.9% (IQR 4.6–15.0%), 8.5% (IQR 4.8–14.6%) and 6.9% (IQR 4.1–11.1%) when using the Framingham, QRISK2, and full and reduced D:A:D scores, respectively. Agreement between the different scores was generally moderate, with the highest level of agreement being between the Framingham and QRISK2 scores (weighted kappa = 0.65) but with most other kappa coefficients in the 0.50–0.60 range.
Conclusions
Estimates of predicted 10‐year CVD risk obtained with commonly used CVD risk prediction tools demonstrate, in general, only moderate agreement among PLWH in the UK. While further validation with clinical endpoints is required, our findings suggest that care should be taken when interpreting any score alone
Depression, lifestyle factors and cognitive function in people living with HIV and comparable HIV-negative controls
We investigated whether differences in cognitive performance between people living with HIV (PLWH) and comparable HIV-negative people were mediated or moderated by depressive symptoms and lifestyle factors.
METHODS:
A cross-sectional study of 637 'older' PLWH aged ≥ 50 years, 340 'younger' PLWH aged < 50 years and 276 demographically matched HIV-negative controls aged ≥ 50 years enrolled in the Pharmacokinetic and Clinical Observations in People over Fifty (POPPY) study was performed. Cognitive function was assessed using a computerized battery (CogState). Scores were standardized into Z-scores [mean = 0; standard deviation (SD) = 1] and averaged to obtain a global Z-score. Depressive symptoms were evaluated via the Patient Health Questionnaire (PHQ-9). Differences between the three groups and the effects of depression, sociodemographic factors and lifestyle factors on cognitive performance were evaluated using median regression. All analyses accounted for age, gender, ethnicity and level of education.
RESULTS:
After adjustment for sociodemographic factors, older and younger PLWH had poorer overall cognitive scores than older HIV-negative controls (P < 0.001 and P = 0.006, respectively). Moderate or severe depressive symptoms were more prevalent in both older (27%; P < 0.001) and younger (21%; P < 0.001) PLWH compared with controls (8%). Depressive symptoms (P < 0.001) and use of hashish (P = 0.01) were associated with lower cognitive function; alcohol consumption (P = 0.02) was associated with better cognitive scores. After further adjustment for these factors, the difference between older PLWH and HIV-negative controls was no longer significant (P = 0.08), while that between younger PLWH and older HIV-negative controls remained significant (P = 0.01).
CONCLUSIONS:
Poorer cognitive performances in PLWH compared with HIV-negative individuals were, in part, mediated by the greater prevalence of depressive symptoms and recreational drug use reported by PLWH
Validation of a novel multivariate method of defining HIV-associated cognitive impairment
Background. The optimum method of defining cognitive impairment in virally suppressed people living with HIV is unknown.
We evaluated the relationships between cognitive impairment, including using a novel multivariate method (NMM), patient–
reported outcome measures (PROMs), and neuroimaging markers of brain structure across 3 cohorts.
Methods. Differences in the prevalence of cognitive impairment, PROMs, and neuroimaging data from the COBRA, CHARTER,
and POPPY cohorts (total n = 908) were determined between HIV-positive participants with and without cognitive impairment defined using the HIV-associated neurocognitive disorders (HAND), global deficit score (GDS), and NMM criteria.
Results. The prevalence of cognitive impairment varied by up to 27% between methods used to define impairment (eg, 48% for HAND
vs 21% for NMM in the CHARTER study). Associations between objective cognitive impairment and subjective cognitive complaints generally were weak. Physical and mental health summary scores (SF-36) were lowest for NMM-defined impairment (P < .05).
There were no differences in brain volumes or cortical thickness between participants with and without cognitive impairment defined using the HAND and GDS measures. In contrast, those identified with cognitive impairment by the NMM had reduced mean
cortical thickness in both hemispheres (P < .05), as well as smaller brain volumes (P < .01). The associations with measures of white
matter microstructure and brain-predicted age generally were weaker.
Conclusion. Different methods of defining cognitive impairment identify different people with varying symptomatology and
measures of brain injury. Overall, NMM-defined impairment was associated with most neuroimaging abnormalities and poorer selfreported health status. This may be due to the statistical advantage of using a multivariate approac
Anthrax edema factor toxicity is strongly mediated by the N-end rule.
Anthrax edema factor (EF) is a calmodulin-dependent adenylate cyclase that converts adenosine triphosphate (ATP) into 3'-5'-cyclic adenosine monophosphate (cAMP), contributing to the establishment of Bacillus anthracis infections and the resulting pathophysiology. We show that EF adenylate cyclase toxin activity is strongly mediated by the N-end rule, and thus is dependent on the identity of the N-terminal amino acid. EF variants having different N-terminal residues varied by more than 100-fold in potency in cultured cells and mice. EF variants having unfavorable, destabilizing N-terminal residues showed much greater activity in cells when the E1 ubiquitin ligase was inactivated or when proteasome inhibitors were present. Taken together, these results show that EF is uniquely affected by ubiquitination and/or proteasomal degradation
Production of cAMP by purified EF N-terminal variants in RAW264.7 cells.
<p>Dilutions of EF N-terminal variants were incubated with 500 ng/mL PA on RAW264.7 cells for 2 h at 37°C before lysis and cAMP measurement. The concentration of EF estimated to induce 50 nM of cAMP production is presented here.</p
Proteasome inhibition enhances toxicity of destabilized EF variants in vivo.
<p>C57BL/6J mice were injected intravenously with 20 µg bortezomib 30 min prior to challenge with 75 µg of EF N-terminal variants+75 µg PA. Animals were monitored every 4-6 h for signs of malaise and/or death. Open circles denote living mice, and black circles denote mouse death.</p
Effects of EF N-terminal variants on C57BL/6J mice.
<p>Kaplan-Meier survival curves (A, C) and malaise rating (B, D) for mice injected intravenously with 25 µg PA + 25 µg EF (A, B) or 75 µg PA + 75 µg EF (C, D). Open circles denote living mice, and black circles denote mouse death. Animals listed as dead at a given time point were removed from successive observations.</p
Prevention of ubiquitination enhances cAMP production of destabilized EF variants.
<p>E36 and ts20 cells were treated with different concentrations of purified EF N-terminal variants with 500 ng/mL PA at either 32°C or 42°C for 2 h before lysis and cAMP measurement. The concentration of EF estimated to induce 50 nM of cAMP production is presented here.</p
Expression and cAMP production of EF N-terminal variants.
<p>(A) SDS-PAGE of concentrated bacterial supernatants from BH460 cells secreting the 20 N-terminal EF variants. The single letter designation for each amino acid is displayed above its respective lane. (B) EF N-terminal variants in concentrated bacterial supernatants were incubated with RAW264.7 cells and 500 ng/mL purified PA with 500 µM IBMX for 2 h at 37°C before lysis and cAMP measurement. Error bars denote standard deviation. White bars denote stabilizing N-terminal amino acids, black bars denote primary destabilizing residues, dark grey bars denote secondary destabilizing residues, and light grey bars denote tertiary destabilizing residues as dictated by the N-end rule pathway. Statistical significance is denoted as summarized from Bonferroni’s multiple comparison test after a one-way ANOVA of the reciprocally transformed data. Transformation of the data was necessary due to significantly different variances of the individual data sets.</p
Validation of a Novel Multivariate Method of Defining HIV-Associated Cognitive Impairment
AbstractBackgroundThe optimum method of defining cognitive impairment in virally suppressed people living with HIV is unknown. We evaluated the relationships between cognitive impairment, including using a novel multivariate method (NMM), patient– reported outcome measures (PROMs), and neuroimaging markers of brain structure across 3 cohorts.MethodsDifferences in the prevalence of cognitive impairment, PROMs, and neuroimaging data from the COBRA, CHARTER, and POPPY cohorts (total n = 908) were determined between HIV-positive participants with and without cognitive impairment defined using the HIV-associated neurocognitive disorders (HAND), global deficit score (GDS), and NMM criteria.ResultsThe prevalence of cognitive impairment varied by up to 27% between methods used to define impairment (eg, 48% for HAND vs 21% for NMM in the CHARTER study). Associations between objective cognitive impairment and subjective cognitive complaints generally were weak. Physical and mental health summary scores (SF-36) were lowest for NMM-defined impairment (P &lt; .05).There were no differences in brain volumes or cortical thickness between participants with and without cognitive impairment defined using the HAND and GDS measures. In contrast, those identified with cognitive impairment by the NMM had reduced mean cortical thickness in both hemispheres (P &lt; .05), as well as smaller brain volumes (P &lt; .01). The associations with measures of white matter microstructure and brain-predicted age generally were weaker.ConclusionDifferent methods of defining cognitive impairment identify different people with varying symptomatology and measures of brain injury. Overall, NMM-defined impairment was associated with most neuroimaging abnormalities and poorer self-reported health status. This may be due to the statistical advantage of using a multivariate approach.</jats:sec
