Catalogue Search | MBRL
Search Results Heading
Explore the vast range of titles available.
MBRLSearchResults
-
DisciplineDiscipline
-
Is Peer ReviewedIs Peer Reviewed
-
Item TypeItem Type
-
SubjectSubject
-
YearFrom:-To:
-
More FiltersMore FiltersSourceLanguage
Done
Filters
Reset
548
result(s) for
"Clifford, David B"
Sort by:
HIV-associated neurocognitive disorder
by
Clifford, David B
,
Ances, Beau M
in
AIDS Dementia Complex - diagnosis
,
AIDS Dementia Complex - virology
,
Antiretroviral agents
2013
Neurological involvement in HIV is often associated with cognitive impairment. Although severe and progressive neurocognitive impairment has become rare in HIV clinics in the era of potent antiretroviral therapy, most patients with HIV worldwide have poor outcomes on formal neurocognitive tests. In this Review, we describe the manifestations of HIV-associated neurocognitive disorder in the era of effective HIV therapy, outline diagnosis and treatment recommendations, and explore the research questions that remain. Although comorbid disorders, such as hepatitis C infection or epilepsy, might cause some impairment, their prevalence is insufficient to explain the frequency with which it is encountered. HIV disease markers, such as viral load and CD4 cell counts, are not strongly associated with ongoing impairment on treatment, whereas cardiovascular disease markers and inflammatory markers are. New cerebrospinal fluid and neuroimaging biomarkers are needed to detect and follow impairment. Ongoing research efforts to optimise HIV therapy within the CNS, and potentially to intervene in downstream mechanisms of neurotoxicity, remain important avenues for future investigation. Ultimately, the full control of virus in the brain is a necessary step in the goal of HIV eradication.
Journal Article
Natalizumab-associated progressive multifocal leukoencephalopathy in patients with multiple sclerosis: lessons from 28 cases
by
Nath, Avindra
,
Simpson, David M
,
Clifford, David B
in
Antibodies, Monoclonal - adverse effects
,
Antibodies, Monoclonal - therapeutic use
,
Antibodies, Monoclonal, Humanized
2010
Treatment of multiple sclerosis with natalizumab is complicated by rare occurrence of progressive multifocal leukoencephalopathy (PML). Between July, 2006, and November, 2009, there were 28 cases of confirmed PML in patients with multiple sclerosis treated with natalizumab. Assessment of these clinical cases will help to inform future therapeutic judgments and improve the outcomes for patients.
The risk of PML increases with duration of exposure to natalizumab over the first 3 years of treatment. No new cases occurred during the first two years of natalizumab marketing but, by the end of November, 2009, 28 cases had been confirmed, of which eight were fatal. The median treatment duration to onset of symptoms was 25 months (range 6–80 months). The presenting symptoms most commonly included changes in cognition, personality, and motor performance, but several cases had seizures as the first clinical event. Although PML has developed in patients without any previous use of disease-modifying therapies for multiple sclerosis, previous therapy with immunosuppressants might increase risk. Clinical diagnosis by use of MRI and detection of JC virus in the CSF was established in all but one case. Management of PML has routinely used plasma exchange (PLEX) or immunoabsorption to hasten clearance of natalizumab and shorten the period in which natalizumab remains active (usually several months). Exacerbation of symptoms and enlargement of lesions on MRI have occurred within a few days to a few weeks after PLEX, indicative of immune reconstitution inflammatory syndrome (IRIS). This syndrome seems to be more common and more severe in patients with natalizumab-associated PML than it is in patients with HIV-associated PML.
Diagnosis of natalizumab-associated PML requires optimised clinical vigilance, reliable and sensitive PCR testing of the JC virus, and broadened criteria for recognition of PML lesions by use of MRI, including contrast enhancement. Optimising the management of IRIS reactions will be needed to improve outcomes. Predictive markers for patients at risk for PML must be sought. It is crucial to monitor the risk incurred during use of natalizumab beyond 3 years.
Journal Article
Treatment of Progressive Multifocal Leukoencephalopathy Using Immune Restoration
by
Dunham, S. Richard
,
Schmidt, Robert
,
Clifford, David B.
in
Animals
,
Antibodies, Monoclonal, Humanized - administration & dosage
,
Antibodies, Monoclonal, Humanized - immunology
2020
Progressive multifocal leukoencephalopathy (PML) is a viral disease of the brain associated with immunodeficiency, immune suppressing medications, and malignancy. In the absence of effective anti-viral therapy for the causative JC virus, immune restoration has emerged as the critical therapeutic alternative. The evolving treatment of PML (and other rare JC virus–associated neurologic syndromes) requires consideration of baseline immune functioning and comorbid diseases while selecting from a number of therapeutic options to restore an effective immune response. This review focuses on the current options for management of PML in typical situations where this disease presents, including several where immune restoration is a standard therapeutic approach such as in PML associated with HIV/AIDS and in multiple sclerosis associated with natalizumab. Other circumstances in which PML occurs including associated with primary immunodeficiencies, malignancies, and transplants present greater challenges to immune reconstitution, but emerging concepts may enhance therapeutic options for these situations. Particular attention is focused on recent experience with checkpoint inhibitors, guidance for MS drug discontinuation, and strategies to monitor and facilitate immune restoration.
Journal Article
Randomized Trial of Central Nervous System–Targeted Antiretrovirals for HIV-Associated Neurocognitive Disorder
by
Ellis, Ronald J.
,
Heaton, Robert K.
,
Umlauf, Anya
in
Acquired immune deficiency syndrome
,
Adult
,
AIDS
2014
Background. Antiretroviral (ARV) medications differentially penetrate across the blood-brain barrier into central nervous system (CNS) tissues, potentially influencing their effectiveness in treating brain infection. Methods. This randomized controlled clinical trial (RCT) called for 120 participants at 5 study sites to be randomized 1:1 to CNS-targeted (CNS-T) or non–CNS-T ART. Entry clinical factors such as ARV experience were balanced across arms using an adaptive randomization approach. The primary outcome, change in neurocognitive performance, was measured as the difference in global deficit score (GDS) from baseline to week 16. Results. The study was terminated early on the recommendation of its data safety monitoring board on the basis of slow accrual and a low likelihood of detecting a difference in the primary outcome. No safety concerns were identified. Of 326 participants screened, 59 met entry criteria and were randomized. The primary intent-to-treat analysis included 49 participants who completed week 16. These comprised 39 men and 10 women with a mean age of 44 years (SD, 10 years), and median nadir and current CD4 + T-cell counts of 175 cells/μL and 242 cells/μL, respectively. The proportional improvement in GDS from baseline was nonsignificantly larger (7%; 95% confidence interval [CI], -31% to 62%) in the CNS-T arm than in the non-CNS-T arm, representing a treatment effect size of 0.09 (95% CI, -.48 to .65). Prespecified secondary analysis showed a trend interaction (P = .087), indicating that participants who had baseline plasma virologic suppression may have benefited from CNS-T. Conclusions. This study found no evidence of neurocognitive benefit for a CNS-T strategy in HIV-associated neurocognitive disorders. A benefit for a subgroup or small overall benefits could not be excluded. Clinical Trials Registration. NCT00624195.
Journal Article
Increasing Neuroinflammation Relates to Increasing Neurodegeneration in People with HIV
by
Rubin, Leah H.
,
Letendre, Scott L.
,
Ellis, Ronald J.
in
Acquired immune deficiency syndrome
,
AIDS
,
Biomarkers
2023
Background: HIV infection causes neuroinflammation and immune activation (NIIA) and systemic inflammation and immune activation (SIIA), which in turn drive neurodegeneration (ND). Cross-sectionally, higher levels of NIIA biomarkers correlate with increased biomarkers of ND. A more convincing confirmation would be a longitudinal demonstration. Methods: PWH in the US multisite CHARTER Aging project were assessed at a baseline visit and after 12 years using standardized evaluations. We measured a panel of 14 biomarkers of NIIA, SIIA, and ND in plasma and CSF at two time points and calculated changes from baseline to the 12-year visit. Factor analysis yielded simplified indices of NIIA, SIIA, and ND. Results: The CSF NIIA factor analysis yielded Factor1 loading on soluble tumor necrosis factor type-2 (sTNFR-II) and neopterin, and Factor2, loading on MCP1, soluble CD14, and IL-6. The SIIA factor analysis yielded Factor1 loading on CRP, D-dimer, and Neopterin; Factor2 loading on sTNFR-II. The ND analysis yielded Factor1 loading on Phosphorylated tau (p-tau) and Aβ42; Factor2 loading on NFL. NIIA Factor1, but not Factor2, correlated with increases in CSF NFL (r = 0.370, p = 0.0002). Conclusions: Increases in NIIA and SIIA in PWH were associated with corresponding increases in ND, suggesting that reducing neuro/systemic inflammation might slow or reverse neurodegeneration.
Journal Article
Predictors of survival and functional outcomes in natalizumab-associated progressive multifocal leukoencephalopathy
2015
Natalizumab, a highly effective therapy for relapsing-remitting multiple sclerosis, is associated with a risk of progressive multifocal leukoencephalopathy (PML). The objective of this analysis was to examine factors predicting survival in a large natalizumab-associated PML global population. Patients with natalizumab-associated PML identified through postmarketing surveillance were followed up for up to 24 months using a structured questionnaire completed by treating physicians. Demographic and clinical characteristics, JC viral load, magnetic resonance imaging (MRI) results, and Expanded Disability Status Scale (EDSS) and Karnofsky Performance Scale (KPS) scores were compared in survivors and nonsurvivors. Kaplan-Meier analysis was used to model survival function. Among the 336 patients included in this analysis, 76 % survived, with mean follow-up time from PML diagnosis of 16.1 months for survivors; mean time from diagnosis to death was 4.7 months for nonsurvivors. Survivors were significantly younger at diagnosis, had significantly lower EDSS scores and higher KPS scores prior to PML diagnosis, and had significantly lower cerebrospinal fluid JC viral load at the time of diagnosis. Patients with less extensive disease on MRI at diagnosis had a higher survival rate than those with widespread disease. Survivors generally had less functional disability pre-PML, at PML diagnosis, and in subsequent months. In survivors, functional disability appeared to stabilize approximately 6 months post-PML diagnosis. In this analysis, younger age at diagnosis, less functional disability prior to PML diagnosis, lower JC viral load at diagnosis, and more localized brain involvement by MRI at the time of diagnosis appeared to predict improved survival in natalizumab-associated PML.
Journal Article
Differences in Neurocognitive Impairment Among HIV-Infected Latinos in the United States
by
Morgello, Susan
,
Fazeli, Pariya
,
Heaton, Robert K.
in
Acquired immune deficiency syndrome
,
Adult
,
AIDS
2018
Objectives: Human immunodeficiency virus (HIV) disproportionately affects Hispanics/Latinos in the United States, yet little is known about neurocognitive impairment (NCI) in this group. We compared the rates of NCI in large well-characterized samples of HIV-infected (HIV+) Latinos and (non-Latino) Whites, and examined HIV-associated NCI among subgroups of Latinos. Methods: Participants included English-speaking HIV+ adults assessed at six U.S. medical centers (194 Latinos, 600 Whites). For overall group, age: M=42.65 years, SD=8.93; 86% male; education: M=13.17, SD=2.73; 54% had acquired immunodeficiency syndrome. NCI was assessed with a comprehensive test battery with normative corrections for age, education and gender. Covariates examined included HIV-disease characteristics, comorbidities, and genetic ancestry. Results: Compared with Whites, Latinos had higher rates of global NCI (42% vs. 54%), and domain NCI in executive function, learning, recall, working memory, and processing speed. Latinos also fared worse than Whites on current and historical HIV-disease characteristics, and nadir CD4 partially mediated ethnic differences in NCI. Yet, Latinos continued to have more global NCI [odds ratio (OR)=1.59; 95% confidence interval (CI)=1.13–2.23; p<.01] after adjusting for significant covariates. Higher rates of global NCI were observed with Puerto Rican (n=60; 71%) versus Mexican (n=79, 44%) origin/descent; this disparity persisted in models adjusting for significant covariates (OR=2.40; CI=1.11–5.29; p=.03). Conclusions: HIV+ Latinos, especially of Puerto Rican (vs. Mexican) origin/descent had increased rates of NCI compared with Whites. Differences in rates of NCI were not completely explained by worse HIV-disease characteristics, neurocognitive comorbidities, or genetic ancestry. Future studies should explore culturally relevant psychosocial, biomedical, and genetic factors that might explain these disparities and inform the development of targeted interventions. (JINS, 2018, 24, 163–175)
Journal Article
Pathogenesis of progressive multifocal leukoencephalopathy and risks associated with treatments for multiple sclerosis: a decade of lessons learned
by
Clifford, David B
,
Major, Eugene O
,
Yousry, Tarek A
in
Binding sites
,
Brain
,
Central nervous system
2018
Progressive multifocal leukoencephalopathy (PML) is a rare, devastating demyelinating disease of the CNS caused by the JC virus (JCV) that occurs in patients with compromised immune systems. Detection of PML in systemically immunocompetent patients with multiple sclerosis treated with natalizumab points to a role for this drug in the pathophysiology of PML. Emerging knowledge of the cellular and molecular biology of JCV infection and the pathogenesis of PML—including interplay of this common virus with the human immune system and features of natalizumab that might contribute to PML pathogenesis—provides new opportunities to monitor viral status and predict risk of JCV-associated disease. In the absence of an effective treatment for PML, early detection of the disease in patients with multiple sclerosis who are receiving natalizumab or other immunomodulatory treatments is vital to minimize CNS injury and avoid severe disability. Frequent MRI, stratified along a clinical and virus-specific immune risk profile, can be used to detect presymptomatic PML. Improved approaches to PML risk stratification are needed to guide treatment choices and surveillance of patients with multiple sclerosis.
Journal Article
Impact of Efavirenz on Neuropsychological Performance and Symptoms in HIV-Infected Individuals
by
Goodkin, Karl
,
Tashima, Karen
,
Yang, Yijun
in
Adult
,
Anti-HIV Agents - adverse effects
,
Antiretroviral drugs
2005
Efavirenz is a commonly used antiretroviral drug that causes neurologic side effects in more than 50% of patients.
To characterize efavirenz-associated neurologic symptoms in a randomized, controlled study of initial antiretroviral treatment.
Substudy of a randomized, double-blind, controlled trial of combination antiretroviral regimens (A5095) that was performed between March 2001 and January 2002.
Multicenter academic clinical trial units.
HIV-infected patients who were initiating therapy in the context of a controlled trial.
Neuropsychological performance measures, including the Digit Symbol Substitution Test and the Trail Making Test (Parts A and B); symptom questionnaires; standardized assessments of sleep quality, anxiety, and depression; and efavirenz plasma concentrations.
Twenty of 303 (6.6%) enrolled participants prematurely discontinued the study. Neuropsychological performance improved in both groups over time without significant differences between patients who were receiving efavirenz and those who were not. The efavirenz group experienced more neurologic symptoms at week 1 (P < 0.001) but not at weeks 4, 12, or 24. A sleep index revealed that participants receiving efavirenz had more \"bad dreams\" during the first week of therapy (P = 0.038). No significant changes in anxiety or depressed mood were noted. Changes in efavirenz-associated neurologic symptoms were correlated to efavirenz plasma concentrations at week 1 but not at later time points. Twelve (6%) patients receiving efavirenz stopped taking the drug before the end of the study because of central nervous system symptoms.
Participant selection may have been biased in favor of patients with fewer psychiatric complications. The study design permitted substitution of a new drug in place of efavirenz in cases of treatment-limiting toxicity.
In a large controlled trial, efavirenz use was associated with neurologic symptoms distinct from depression and anxiety that began early in therapy but resolved by week 4. Improvement in neuropsychological performance was comparable in patients who were receiving efavirenz and those who were not.
Journal Article
Higher iron stores and the HFE 187C>G variant delay onset of peripheral neuropathy during combination antiretroviral therapy
by
Wen, Wanqing
,
Hulgan, Todd
,
Kallianpur, Asha R.
in
Acquired immune deficiency syndrome
,
Adult
,
AIDS
2020
People with HIV (PWH) continue to experience sensory neuropathy and neuropathic pain in the combination antiretroviral therapy (cART) era for unclear reasons. This study evaluated the role of iron in a previously reported association of iron-loading hemochromatosis (HFE) gene variants with reduced risk of neuropathy in PWH who received more neurotoxic cART, since an iron-related mechanism also might be relevant to neuropathic symptoms in PWH living in low-resource settings today.
This time-to-event analysis addressed the impact of systemic iron levels on the rapidity of neuropathy onset in PWH who initiated cART.
Soluble transferrin receptor (sTFR), the sTFR-ferritin index of iron stores, and high-sensitivity C-reactive protein (hsCRP) levels were determined in stored baseline sera from participants of known HFE genotype from AIDS Clinical Trials Group (ACTG) Study 384, a multicenter randomized clinical trial that evaluated cART strategies. Associations with incident neuropathy were evaluated in proportional-hazards, time-to-event regression models, adjusting for potential confounders.
Of 151 eligible participants with stored serum who were included in the original genetic study, 43 had cART-associated neuropathy; 108 had sufficient serum for analysis, including 30 neuropathy cases. Carriers of HFE variants had higher systemic iron (lower sTFR and sTFR-ferritin index) and lower hsCRP levels than non-carriers (all p<0.05). Higher sTFR or iron stores, the HFE 187C>G variant, and lower baseline hsCRP were associated with significantly delayed neuropathy in self-reported whites (n = 28; all p-values<0.05), independent of age, CD4+ T-cell count, plasma HIV RNA, and cART regimen.
Higher iron stores, the HFE 187C>G variant, and lower hsCRP predicted delayed onset of neuropathy among self-reported white individuals initating cART. These findings require confirmation but may have implications for cART in HIV+ populations in areas with high endemic iron deficiency, especially those PWH in whom older, more neurotoxic antiretroviral drugs are occasionally still used.
Journal Article