Publications by authors named "Letendre S"

Methamphetamine dependence is a common comorbid condition among people living with HIV, and may exacerbate HIV-associated neurocognitive disorders. Animal models of neuroAIDS suggest that the gp120 protein may also cause cognitive impairment. The present work evaluated the separate and combined effects of HIV/gp120 and methamphetamine on learning and executive functions in both humans and transgenic mice.

View Article and Find Full Text PDF

Objectives: HIV-associated brain injury persists despite combination antiretroviral therapy, but contributing factors remain poorly understood. We postulated that inflammation-associated biomarkers will be associated with cerebral injury on proton magnetic resonance spectroscopy in chronically HIV-infected subjects.

Methods: Five biomarkers were measured in 197 HIV-infected subjects: soluble CD14, MCP-1, IP-10, MIP-1β, and fractalkine.

View Article and Find Full Text PDF

Objectives: To identify prognostic surrogate markers for change in cognitive states of HIV-infected patients.

Design: Longitudinal cerebrospinal fluid (CSF) samples were collected from 98 HIV-infected patients identified by temporal change in cognitive states classified as normal, stably impaired, improving and worsening.

Methods: The metabolic composition of CSF was analysed using H nuclear magnetic resonance (H NMR) spectroscopy that focused on energy metabolites.

View Article and Find Full Text PDF

HIV+ persons with co-occurring bipolar disorder (HIV+/BD+) have elevated rates of medication nonadherence. We conducted a 30-day randomized controlled trial of a two-way, text messaging system, iTAB (n = 25), compared to an active comparison (CTRL) (n = 25) to improve antiretroviral (ARV) and psychotropic (PSY) adherence and dose timing. Both groups received medication adherence psychoeducation and daily texts assessing mood.

View Article and Find Full Text PDF

Objective: To investigate the effect of hepatitis C virus (HCV) on neurocognitive performance in chronically HIV-infected patients enrolled in the CNS HIV Antiretroviral Therapy Effects Research (CHARTER) study.

Methods: A total of 1,582 participants in CHARTER who were tested for HCV antibody underwent neurocognitive testing; serum HCV RNA was available for 346 seropositive patients. Neurocognitive performance was compared in 408 HCV-seropositive and 1,174 HCV-seronegative participants and in a subset of 160 seropositive and 707 seronegative participants without serious comorbid neurologic conditions that might impair neurocognitive performance, using linear regression and taking into account HIV-associated and demographic factors (including IV drug use) and liver function.

View Article and Find Full Text PDF

Objective: We tested our hypothesis that abdominal obesity when associated with increased levels of systemic and central nervous system immunoinflammatory mediators contributes to neurocognitive impairment (NCI).

Design: Cross-sectional.

Setting: Six Academic Centers.

View Article and Find Full Text PDF

Background: Human immunodeficiency virus (HIV)-associated neurocognitive disorders (HAND) can show variable clinical trajectories. Previous longitudinal studies of HAND typically have been brief, did not use adequate normative standards, or were conducted in the context of a clinical trial, thereby limiting our understanding of incident neurocognitive (NC) decline and recovery.

Methods: We investigated the incidence and predictors of NC change over 16-72 (mean, 35) months in 436 HIV-infected participants in the CNS HIV Anti-Retroviral Therapy Effects Research cohort.

View Article and Find Full Text PDF

Treatment of hepatitis C virus (HCV) with pegylated interferon and ribavirin (IFN/RBV) can be associated with neuropsychiatric side effects, which may necessitate dose reductions or treatment discontinuation. This study aimed to characterize the time course and predictors of cognitive and affective/mood symptoms after IFN/RBV treatment initiation. Forty individuals enrolled in a longitudinal project underwent comprehensive cognitive, medical, and psychiatric assessment at baseline and 10 weeks, 6 months, 12 months, and 18 months after treatment initiation.

View Article and Find Full Text PDF

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.

View Article and Find Full Text PDF

Apathy is a relatively common psychiatric syndrome in HIV infection, but little is known about its neural correlates. In the present study, we examined the associations between apathy and diffusion tensor imaging (DTI) indices in key frontal white matter regions in the thalamocorticostriatal circuit, which has been implicated in the expression of apathy. Nineteen participants with HIV infection and 19 demographically comparable seronegative comparison subjects completed the Apathy subscale of the Frontal Systems Behavioral Scale as a part of a comprehensive neuropsychiatric research evaluation.

View Article and Find Full Text PDF

Excessive alcohol use is common among people living with HIV. Given the growing prevalence of older HIV+ adults and observations indicating higher risk for neurocognitive impairment in older adults with either HIV infection or alcoholism, an increased understanding of their combined impact in the context of this increasingly aged population is crucial. We conducted comprehensive neurocognitive assessment in 112 older HIV+ individuals aged 50 to 69 years.

View Article and Find Full Text PDF

Background: Having identified substance abuse as an issue of concern in their community, the Alexis Nakota Sioux Nation invited University of Alberta researchers to partner on the cultural adaptation, delivery, and evaluation of a school-based drug and alcohol abuse prevention program. Researchers conducted a literature review of available drug and alcohol prevention programs for children and youth, identifying the Life Skills Training (LST) program as a viable model for cultural adaptation.

Objectives: Four program objectives were developed: (1) Review and cultural adaptation of the elementary and junior high LST programs, (2) delivery of the adapted programs, (3) measurement of changes in students' knowledge of the negative effects of drug and alcohol use, attitudes toward drugs and alcohol, drug and alcohol refusal and life skills, and changes in self-esteem/self-concept, and (4) documentation of the community's experience of the project.

View Article and Find Full Text PDF

HIV sensory neuropathy and distal neuropathic pain (DNP) are common, disabling complications associated with combination antiretroviral therapy (cART). We previously associated iron-regulatory genetic polymorphisms with a reduced risk of HIV sensory neuropathy during more neurotoxic types of cART. We here evaluated the impact of polymorphisms in 19 iron-regulatory genes on DNP in 560 HIV-infected subjects from a prospective, observational study, who underwent neurological examinations to ascertain peripheral neuropathy and structured interviews to ascertain DNP.

View Article and Find Full Text PDF

Unlabelled: Increased plasma lactate levels can indicate the presence of metabolic disorders in HIV infected individuals.

Objective: To determine whether a portable analyzer is valid for measuring cerebrospinal fluid (CSF) and plasma lactate levels in HIV infected individuals.

Method: CSF and plasma were collected from 178 subjects.

View Article and Find Full Text PDF

HIV involvement of the CNS continues to be a significant problem despite successful use of combination antiretroviral therapy (cART). Drugs of abuse can act in concert with HIV proteins to damage glia and neurons, worsening the neurotoxicity caused by HIV alone. Methamphetamine (METH) is a highly addictive psychostimulant drug, abuse of which has reached epidemic proportions and is associated with high-risk sexual behavior, increased HIV transmission, and development of drug resistance.

View Article and Find Full Text PDF

Background: Integrase inhibitors are a promising class of antiretroviral drugs to treat chronic human immunodeficiency virus (HIV) infection. During HIV infection, macrophages can extravasate from the blood to the brain, while producing chemotaxic proteins and cytokines, which have detrimental effects on central nervous system cells. The main goal of this study was to understand the effects of raltegravir (RAL) on human brain macrophage production of immune-mediators when infected with HIV, but did not compare with other antiretroviral agents.

View Article and Find Full Text PDF

Detectable human immunodeficiency virus (HIV) RNA in the cerebrospinal fluid (CSF) is associated with central nervous system (CNS) complications. We developed the CSF HIV risk score through prediction modeling to estimate the risk of detectable CSF HIV RNA (threshold >50 copies/mL) to help identify persons who might benefit most from CSF monitoring. We used baseline data from 1,053 participants receiving combination antiretroviral therapy who were enrolled in the 6-center, US-based CNS HIV Antiretroviral Therapy Effects Research (CHARTER) prospective cohort in 2004-2007.

View Article and Find Full Text PDF

Background: Dolutegravir (DTG), a once-daily, human immunodeficiency virus type 1 (HIV-1) integrase inhibitor, was evaluated for distribution and antiviral activity in cerebrospinal fluid (CSF).

Methods: ING116070 is an ongoing, single-arm, open-label, multicenter study in antiretroviral therapy-naive, HIV-1-infected adults. Subjects received DTG (50 mg) plus abacavir/lamivudine (600/300 mg) once daily.

View Article and Find Full Text PDF

Background: Compelling data exist that show that normal levels of progranulin (PGRN) are required for successful CNS aging. PGRN production is also modulated by inflammation and infection, but no data are available on the production and role of PGRN during CNS HIV infection.

Methods: To determine the relationships between PGRN and HIV disease, neurocognition, and inflammation, we analyzed 107 matched CSF and plasma samples from CHARTER, a well-characterized HIV cohort.

View Article and Find Full Text PDF

Objective: While HIV-associated neurocognitive disorders (HAND) remain prevalent despite combination antiretroviral therapy (CART), the clinical relevance of asymptomatic neurocognitive impairment (ANI), the most common HAND diagnosis, remains unclear. We investigated whether HIV-infected persons with ANI were more likely than those who were neurocognitively normal (NCN) to experience a decline in everyday functioning (symptomatic decline).

Methods: A total of 347 human participants from the CNS HIV Anti-Retroviral Therapy Effects Research (CHARTER) cohort were NCN (n = 226) or had ANI (n = 121) at baseline.

View Article and Find Full Text PDF

Visual function abnormalities are common in people living with HIV disease (PLWH) without retinitis, even after improvement in immune status. Abnormalities such as reduced contrast sensitivity, altered color vision, peripheral visual field loss, and electrophysiological changes are related to a combination of retinal dysfunctions, involving inner and outer retinal structures. The standard protocol for testing vision performance in clinical practice is the Early Treatment Diabetic Retinopathy Study (ETDRS) chart.

View Article and Find Full Text PDF

Background: Prior research has demonstrated neuropsychological (NP) impairment in persons with histories of injection drug use (IDU), hepatitis C virus (HCV) infection, and methadone maintenance treatment (MMT), individually, but little is known about the NP effects of these three risk factors in combination. This issue is particularly important in China, which is addressing its highly HCV-comorbid IDU epidemic with widespread government sponsored MMT, especially in light of recent evidence suggesting that methadone may be neuroprotective in some circumstances.

Methods: We administered a comprehensive NP test battery to 195 Chinese heroin IDU individuals taking MMT (IDU+ group), the majority of whom were also HCV+ (87%; n=169), and compared their NP performance to that of 198 demographically comparable, non-IDU Chinese controls (IDU- group).

View Article and Find Full Text PDF

Prior studies examining the combined adverse effects of HIV and methamphetamine (MA) on the central nervous system (CNS) have focused on younger to middle-aged adults with recent MA use diagnoses. Aging, HIV, and MA all converge on prefrontal and temporolimbic neural systems and confer independent risk for neurocognitive and functional decline. Thus, this study sought to determine the residual impact of a remote history of MA dependence on neurocognitive and real-world outcomes in older people living with HIV (PLWH).

View Article and Find Full Text PDF