Comparison of Rates of Impairment Between Three Sets of Normative Data for Spanish-speakers of Mexican Origin in a Healthy Cohort

Objective

With over 37 million Spanish-speakers, the US is the second country in the world with the largest number of Spanish-speakers. Identification of neurological dysfunction via neuropsychological testing for this language group requires knowledgeable application of available tests and normative data. Accordingly, we investigated whether rates of neurocognitive impairment (NCI) varied based on the Spanish language normative method used.

Method

Participants included 254 healthy native Spanish-speakers (Age: M = 37.3, SD = 10.4; Education: M = 10.7, SD = 4.3; 59% Female; 78.7% of known Mexican origin/descent) living in the US-Mexico border region. Participants completed the Hopkins Verbal Learning Test-Revised (HVLT-R), Trail Making Test (TMT) A&B, and Animal Naming in Spanish. Raw test scores were converted to demographically-adjusted T-scores based on normative adjustments developed for this population (Neuropsychological Norms for the US-Mexico Border Region in Spanish [NP-NUMBRS]) and norms developed based on samples in Mexico (Latin American Norms from Mexico [LAN-M] and NEUROPSI). Rates of NCI (T < 40) based on the different normative methods were compared via McNemar’s tests.

Results

Rates of NCI for NP-NUMBRS and NEUROPSI fell between the expected 15-17%. Compared to NP-NUMBRS, significantly lower rates were found when applying LAN-M for HVLT-R Total (4%) and Delayed Recall (8%), TMT-A (1%), and Animal Naming (10%; all ps < .0002). No significant differences were found for TMT-B (p > .05).

Conclusions

Present findings revealed that while the NP-NUMBRS and NEUROPSI norms yielded similar NCI rates, and LAN-M norms underestimated NCI on three tests. This highlights the importance of carefully considering available normative adjustments for Spanish-speakers when applying them to specific populations.

Catechol-O-methyltransferase polymorphism Val158Met is associated with distal neuropathic pain in HIV-associated sensory neuropathy

BACKGROUND

Many of those aging with HIV suffer from distal neuropathic pain (DNP) due to HIV-associated sensory neuropathy (HIV-SN). Prior studies have linked chronic pain conditions to a variant of the catechol-O-methyltransferase (COMT), ValMet. This variant confers reduced enzymatic activity and results in higher synaptic dopamine levels. Here we examined the role of ValMet as a predictor of DNP in HIV-SN.

METHODS

In 1044 HIV-infected individuals enrolled in CNS HIV Antiretroviral Therapy Effects Research, an observational study across six US institutions, we characterized the relationship between ValMet and DNP in HIV-SN. Participants underwent neurologic examination and genotyping. Stratification into genetic ancestry groups was employed to eliminate bias due to genetic background.

FINDINGS

Of 590 participants with HIV-SN, 38% endorsed DNP, 24% reported nonpainful symptoms of neuropathy (paresthesia and numbness), and 38% were asymptomatic. Compared with asymptomatic HIV-SN, ValMet was associated with 2.3 higher odds of DNP. There were no increased odds of nonpainful symptoms. The association remained significant after controlling for other risk factors for DNP: lifetime diagnosis of depression, older age, ancestry, cumulative exposure to dideoxynucleoside antiretrovirals, diabetes, and nadir CD4. Stratified by genetic ancestry, the association between ValMet and DNP was significant in European and African genetic ancestry.

INTERPRETATION

ValMet may be a genetic marker for susceptibility to DNP in HIV-SN. Our findings support the notion that differences in pain processing mediated by COMT-related dopamine signaling play a role in susceptibility to DNP in HIV-SN. Because prior studies suggest that the COMT allele may influence dose-response relationships with opioid treatment, knowing COMT genotype could influence management.

Linked CSF reduction of phosphorylated tau and IL-8 in HIV associated neurocognitive disorder

HIV-associated neurocognitive disorder (HAND) is a common condition in both developed and developing nations, but its cause is largely unknown. Previous research has inconsistently linked Alzheimer’s disease (AD), viral burden, and inflammation to the onset of HAND in HIV-infected individuals. Here we simultaneously measured cerebrospinal fluid (CSF) levels of established amyloid and tau biomarkers for AD, viral copy numbers, and six key cytokines in 41 HIV-infected individuals off combination anti-retroviral therapy (14 with HAND) who underwent detailed clinical and neuropsychological characterization, and compared their CSF patterns with those from young healthy subjects, older healthy subjects with normal cognition, and older people with AD. HAND was associated with the lowest CSF levels of phosphorylated tau (p-Tau₁₈₁) after accounting for age and race. We also found very high CSF levels of the pro-inflammatory interferon gamma-induced protein 10 (IP-10/CXCL10) in HIV regardless of cognition, but elevated CSF interleukin 8 (IL-8/CXCL8) only in HIV-NC but not HAND. Eleven HIV-infected subjects underwent repeat CSF collection six months later and showed strongly correlated longitudinal changes in p-Tau₁₈₁ and IL-8 levels (R = 0.841). These data suggest reduced IL-8 relative to IP-10 and reduced p-Tau₁₈₁ to characterize HAND.

Self-initiated continuation of and adherence to HIV pre-exposure prophylaxis (PrEP) after PrEP demonstration project roll-off in men who have sex with men: associations with risky decision making, impulsivity/disinhibition, and sensation seeking

The objective of this study was to examine differences in the levels of risky decision making and other frontal system behavior constructs in relation to self-initiated continuance of HIV pre-exposure prophylaxis (PrEP) and PrEP adherence outcomes among men who have sex with men (MSM) following completion of a clinical PrEP trial. At the last PrEP trial visit, study provided PrEP was discontinued and participants were navigated to the community for PrEP continuation. In this cross-sectional analysis, 84/187 (45%) MSM who completed a prospective observational post-PrEP trial follow-up visit at the University of California San Diego were included. PrEP adherence was measured using dried blood spot tenofovir diphosphate (TFV-DP) levels. Risky decision making was assessed using the Iowa Gambling Task (IGT) and the Balloon Analogue Risk Task (BART), while impulsivity/disinhibition, sensation seeking, and substance use were assessed via standardized self-report questionnaires. A total of 58/84 (69%) of MSM who completed the 12-month post-study visit continued PrEP. Of those, n = 46 (79%) reached TFV-DP levels associated with adequate adherence. Individuals who elected to continue PrEP 12 months post-trial had riskier decision making on BART, but less impulsivity/disinhibition compared to individuals who did not continue PrEP. Neither risky decision making nor impulsivity/disinhibition/sensation seeking nor substance use correlated with PrEP adherence. Our findings suggest that those with risky decision making may have greater insight into their HIV risks, and therefore be more likely to continue to use PrEP. However, elevated impulsivity/disinhibition, indicative of greater neurobehavioral alterations, was negatively associated with PrEP continuance and is a potential target for future interventions to help people link to PrEP.

Impaired insulin sensitivity is associated with worsening cognition in HIV-infected patients

OBJECTIVE

To determine the association of insulin sensitivity and metabolic status with declining cognition in HIV-infected individuals.

METHODS

We conducted targeted clinical and metabolic measures in longitudinal plasma samples obtained from HIV-infected patients enrolled in the Central Nervous System HIV Anti-Retroviral Therapy Effects Research Study (CHARTER). Findings were validated with plasma samples from the Multicenter AIDS Cohort Study (MACS). Patients were grouped according to longitudinally and serially assessed cognitive performance as having stably normal or declining cognition.

RESULTS

Patients with declining cognition exhibited baseline hyperinsulinemia and elevated plasma c-peptide levels with normal c-peptide/insulin ratios, suggesting that insulin production was increased, but insulin clearance was normal. The association of hyperinsulinemia with worsening cognition was further supported by low high-density lipoprotein (HDL), high low-density lipoprotein/HDL ratio, and elevated cholesterol/HDL ratio compared to patients with stably normal cognition.

CONCLUSIONS

These findings suggest that hyperinsulinemia and impaired insulin sensitivity are associated with cognitive decline in antiretroviral therapy-treated HIV-infected patients.

Generalizability of demographically corrected Zambian neuropsychological norms to South African women

Objective: Demographically corrected norms typically account for the effects of age, education, and in some cases, sex and other factors (e.g. race/ethnicity). However, generalizability of normative standards to different countries and ethnic groups is not universal. This study sought to determine whether demographically specific Zambian neuropsychological norms would generalize to a group of South African women.Method: 212 English-Xhosa bilingual, South African (SA) women were administered a comprehensive neuropsychological (NP) test battery in either English or Xhosa. We examined rates of "impairment" using Global Deficit Scores (GDS) based upon published, demographically corrected norms from a nearby African country (Zambia). Using multiple regression, we examined the extent to which Zambian norms "corrected" for the effects of age and education in this SA sample.Results: Compared to the normative standards from Zambia, the South African women performed somewhat worse than expected on a few test measures and better than expected on others, but their GDS and associated "impairment" rates were close to what was seen in Zambia. Demographically corrected Zambian norms adequately adjusted for the effects of age and years of education in this sample of SA women, with the exception that Zambian norms appeared to "under correct" for the positive effects of years of education on tests of information processing speed.Conclusions: Demographically corrected norms developed for Zambia may adequately adjust for the effects of age in SA women. Further research is needed to determine whether additional corrections for education are needed in SA, especially for tests of information processing speed.

Effects of HIV on executive function and verbal fluency in Cameroon

HIV-associated neurocognitive disorders (HAND) are frequently associated with impaired executive function and verbal fluency. Given limited knowledge concerning HAND in Sub-Saharan-Africa and lack of Cameroonian adult neuropsychological (NP) test norms, we administered four executive function [Halstead Category Test (HCT), Wisconsin Card Sorting Test (WCST), Color Trails-II (CTT2), and Stroop Color-Word-Interference (SCWT)] and three verbal fluency (Category, Action, and Letter Fluency) tests to 742 adult Cameroonians (395 HIV-, 347 HIV+). We developed demographically-corrected NP test norms and examined the effects of HIV and related variables on subjects' executive function and verbal fluency. HIV+ subjects had significantly lower T-scores on CTT2 (P = 0.005), HCT (P = 0.032), WCST (P < 0.001); lower executive function composite (P = 0.002) and Action Fluency (P = 0.03) T-scores. ART, viremia, and CD4 counts did not affect T-scores. Compared to cases harboring other viral subtypes, subjects harboring HIV-1 CRF02_AG had marginally higher CTT2 T-scores, significantly higher SCWT (P = 0.015) and executive function (P = 0.018) T-scores. Thus, HIV-1 infection in Cameroon is associated with impaired executive function and some aspects of verbal fluency, and viral genotype influenced executive function. We report the first normative data for assessing executive function and verbal fluency in adult Cameroonians and provide regression-based formulas for computing demographically-adjusted T-scores. These norms will be useful for investigating HIV/AIDS and other diseases affecting cognitive functioning in Cameroon.

Neurofilament light chain in blood is negatively associated with neuropsychological performance in HIV-infected adults and declines with initiation of antiretroviral therapy

HIV-associated neurocognitive disorder (HAND) persists in the combination antiretroviral therapy (cART) era and is associated with diminished quality of life. The disorder remains challenging to diagnose given the requirement for comprehensive neuropsychological testing. Blood biomarkers are needed to facilitate the diagnosis of HAND and to gauge neurological response to antiretroviral therapy. We performed a study of plasma neurofilament light chain (NFL) that included 37 HIV-infected and 54 HIV-negative adults. In the univariate mixed-effect model involving HIV-infected participants, there was a statistically significant linear relationship between composite neuropsychological score (NPT-11) and plasma NFL (slope = - 9.9, standard error = 3.0 with 95% confidence interval - 3.2 to - 16.6 and p = 0.008 when testing slope = 0). Similarly, in the multivariate mixed-effect model, higher plasma NFL was significantly associated with worse NPT-11 (slope = - 11.5, standard error = 3.3 with 95% confidence interval - 3.7 to - 19.0 and p = 0.01 when testing slope = 0). The association between NPT-11 and NFL appeared to be driven by the group of individuals off cART. In a subset of participants who had visits before and after 24 weeks on cART (n = 11), plasma NFL declined over time (median = 22.7 versus 13.4 pg/ml, p = 0.02). In contrast, plasma NFL tended to increase over time among HIV-negative participants (median 10.3 versus 12.6 pg/ml, p = 0.065, n = 54). Plasma NFL therefore shows promise as a marker of neuropsychological performance during HIV. Larger studies are needed to determine if NFL could serve as a diagnostic tool for HAND during suppressive cART.

Impact of Antiretroviral Regimens on Cerebrospinal Fluid Viral Escape in a Prospective Multicohort Study of Antiretroviral Therapy-Experienced Human Immunodeficiency Virus-1-Infected Adults in the United States

Background

Cerebrospinal fluid (CSF) viral escape occurs in 4%-20% of human immunodeficiency virus (HIV)-infected adults, yet the impact of antiretroviral therapy (ART) on CSF escape is unclear.

Methods

A prospective study of 1063 participants with baseline plasma viral load (VL) ≤400 copies/mL between 2005 and 2016. The odds ratio (OR) for ART regimens (protease inhibitor with nucleoside reverse transcriptase inhibitor [PI + NRTI] vs other ART) and CSF escape was estimated using mixed-effects models.

Results

Baseline mean age was 46 years, median plasma VL, and CD4 count were 50 copies/mL, and 424 cells/μL, respectively. During median follow-up of 4.4 years, CSF escape occurred in 77 participants (7.2%). PI + NRTI use was an independent predictor of CSF escape (OR, 3.1; 95% confidence interval, 1.8-5.0) in adjusted analyses and models restricted to plasma VL ≤50 copies/mL (P < .001). Regimens that contained atazanavir (ATV) were a stronger predictor of CSF viral escape than non-ATV PI + NRTI regimens. Plasma and CSF M184V/I combined with thymidine-analog mutations were more frequent in CSF escape vs no escape (23% vs 2.3%). Genotypic susceptibility score-adjusted central nervous system (CNS) penetration-effectiveness (CPE) values were calculated for CSF escape with M184V/I mutations (n = 34). Adjusted CPE values were low (<5) for CSF in 27 (79%), indicating suboptimal CNS drug availability.

Conclusions

PI + NRTI regimens are independent predictors of CSF escape in HIV-infected adults. Reduced CNS ART bioavailability may predispose to CSF escape in patients with M184V/I mutations.

Controlling alcohol availability through local policy: an observational study to evaluate Cumulative Impact Zones in a London borough

Background

Cumulative impact zones (CIZs) are a discretionary policy lever available to local government, used to restrict the availability of alcohol in areas deemed already saturated. Despite little evidence of their effect, over 200 such zones have been introduced. This study explores the impact of three CIZs on the licensing of venues in the London Borough of Southwark.

Methods

Using 10 years of licensing data, we examined changes in the issuing of licences on the introduction of three CIZs within Southwark, relative to control areas. The number of licence applications made (N = 1110), the number issued, and the proportion objected to, were analysed using negative binomial regression.

Results

In one area tested, CIZ implementation was associated with 119% more licence applications than control areas (incidence rate ratios (IRR) = 2.19, 95% confidence intervals (CI): 1.29-3.73, P = 0.004) and 133% more licences granted (IRR = 2.33, 95% CI: 1.31-4.16, P = 0.004). No significant effect was found for the other two areas. CIZs were found to have no discernible effect on the relative proportion of licence applications receiving objections.

Conclusions

CIZs are proposed as a key lever to limit alcohol availability in areas of high outlet density. We found no evidence that CIZ establishment reduced the number of successful applications in Southwark.

Neurocognitive impairment with hepatitis C and HIV co-infection in Southern Brazil

Although cognitive impairment has been well documented in human immunodeficiency virus (HIV) and hepatitis C virus (HCV) mono-infections, research on neurocognitive effects is limited in the context of HIV/HCV co-infection. The aims of this study were to explore the interplay between HIV and HCV infections in the expression of neurocognitive impairment (NCI), and to examine the differences in test performance between HIV/HCV co-infected and HIV or HCV mono-infected patients. A total of 128 participants from Southern Brazil underwent a comprehensive neuropsychological (NP) battery comprising 18 tests. Participants were grouped according to their serological status: HCV mono-infected (n = 20), HIV mono-infected (n = 48), HIV/HCV co-infected (n = 12), and HIV-/HCV-uninfected controls (n = 48). The frequencies of HIV subtypes B and C between the HIV mono-infected and HIV/HCV co-infected groups were comparable. There was greater prevalence of neuropsychological impairment among all three infection groups compared with the uninfected control group, but no statistically significant differences among mono- and co-infected groups were found. HCV infection was associated with cognitive deficits, independently of liver dysfunction. HCV infection did not show an additive effect on neurocognitive function among HIV+. NCI was independent of HCV RNA on peripheral blood, CSF, and hepatic injury. While we did not find additive global effect, in the present study, there was some evidence of additive HIV/HCV co-infection effects in speed of information processing, executive function, and verbal fluency domains when comparing the co-infected group with the other three groups. NP impairment was not dependent on HCV subtypes.

Soluble membrane attack complex in the blood and cerebrospinal fluid of HIV-infected individuals, relationship to HIV RNA, and comparison with HIV negatives

The soluble membrane attack complex (sMAC) represents the terminal product of the complement cascade. We enrolled 47 HIV+ adults (12 of whom underwent a second visit at least 24weeks after starting therapy) as well as 11 HIV negative controls. At baseline, cerebrospinal fluid (CSF) sMAC was detectable in 27.7% of HIV+ individuals. CSF sMAC correlated with CSF HIV RNA levels and was more likely to be detectable in HIV+ individuals on cART compared to HIV negative controls. In HIV+ participants, there were negative association trends between sMAC and neurocognitive performance but these did not reach statistical significance.

Cerebrospinal fluid cell-free mitochondrial DNA is associated with HIV replication, iron transport, and mild HIV-associated neurocognitive impairment

Background

Mitochondria are abundant organelles critical for energy metabolism and brain function. Mitochondrial DNA (mtDNA), released during cellular injury and as part of the innate immune response to viral pathogens, contains CpG motifs that act as TLR-9 ligands. We investigated relationships between cerebrospinal fluid (CSF) cell-free mtDNA levels and HIV viral load (VL), biomarkers of inflammation and iron transport, and neurocognitive (NC) function in the CNS HIV Antiretroviral Therapy Effects Research (CHARTER) cohort.

Methods

We quantified cell-free mtDNA in CSF by droplet digital PCR in 332 CHARTER participants who underwent comprehensive neuropsychiatric evaluation. NC performance was assessed using the global deficit score (GDS) as either a continuous or a binary measure (GDS ≥ 0.5, impaired vs. GDS < 0.5, unimpaired). CSF, clinical, and biomarker data from the earliest available time point were analyzed. Cell-free mtDNA associations with CSF inflammation and iron-related biomarkers [CXCL10, IL-6, IL-8, TNF-a, transferrin (TF), ceruloplasmin (CP), and vascular endothelial growth factor (VEGF)], VL, and GDS were evaluated by multivariable regression.

Results

CSF cell-free mtDNA levels were significantly lower in participants with undetectable (vs. detectable) VL in either plasma (p < 0.001) or CSF (p < 0.001) and in those on antiretroviral therapy (ART; p < 0.001). Participants on ART with undetectable VL in both CSF and plasma had lower mtDNA levels than those with detectable VL in both compartments (p = 0.001). Higher mtDNA levels were observed in participants in the highest vs. lowest tertile (T3 vs. T1) of CSF CXCL10 (T3 vs. T1, p < 0.001) and TNF-a (T3 vs. T1, p < 0.05) in unadjusted analyses. MtDNA levels also correlated with CSF leukocyte count. After adjusting for CSF leukocyte count and VL, mtDNA levels were also associated with other inflammation- and iron-related biomarkers in CSF, including TF (T3 vs. T1, p < 0.05) and CP (T3 vs. T1, p < 0.05). With additional correction for ART use, mtDNA was also negatively associated with CSF VEGF (p < 0.05) and IL-6 (p = 0.05). We observed no associations of CSF mtDNA levels with age or GDS-defined NC impairment.

Conclusions

CSF cell-free mtDNA levels were associated with HIV RNA and ART status, as well as with biomarkers of iron transport and VEGF, a growth factor with known effects on mitochondrial integrity and autophagy. CSF mtDNA may be a biomarker of iron dysregulation and/or neuroinflammation during HIV infection.

Electronic supplementary material

The online version of this article (doi:10.1186/s12974-017-0848-z) contains supplementary material, which is available to authorized users.

European Mitochondrial DNA Haplogroups are Associated with Cerebrospinal Fluid Biomarkers of Inflammation in HIV Infection

Background:

Mitochondrial DNA (mtDNA) haplogroups are ancestry-related patterns of single-nucleotide polymorphisms that are associated with differential mitochondrial function in model systems, neurodegenerative diseases in HIV-negative populations, and chronic complications of HIV infection, including neurocognitive impairment. We hypothesized that mtDNA haplogroups are associated with neuroinflammation in HIV-infected adults.

Methods:

CNS HIV Antiretroviral Therapy Effects Research (CHARTER) is a US-based observational study of HIV-infected adults who underwent standardized neurocognitive assessments. Participants who consented to DNA collection underwent whole blood mtDNA sequencing, and a subset also underwent lumbar puncture. IL-6, IL-8, TNF-α (high-sensitivity), and IP-10 were measured in cerebrospinal fluid (CSF) by immunoassay. Multivariable regression of mtDNA haplogroups and log-transformed CSF biomarkers were stratified by genetic ancestry using whole-genome nuclear DNA genotyping (European [EA], African [AA], or Hispanic ancestry [HA]), and adjusted for age, sex, antiretroviral therapy (ART), detectable CSF HIV RNA, and CD4 nadir. A total of 384 participants had both CSF cytokine measures and genetic data (45% EA, 44% AA, 11% HA, 22% female, median age 43 years, 74% on ART).

Results:

In analyses stratified by the 3 continental ancestry groups, no haplogroups were significantly associated with the 4 biomarkers. In the subgroup of participants with undetectable plasma HIV RNA on ART, European haplogroup H participants had significantly lower CSF TNF-α (P = 0.001).

Conclusions:

Lower CSF TNF-α may indicate lower neuroinflammation in the haplogroup H participants with well-controlled HIV on ART.

The impact of ethnicity/race on the association between the Veterans Aging Cohort Study (VACS) Index and neurocognitive function among HIV-infected persons

The Veterans Aging Cohort Study (VACS) Index was developed as a risk index for health outcomes in HIV, and it has been consistently associated with mortality. It shows a significant, yet relatively weak, association with neurocognitive impairment, and little is known about its utility among ethnic/racial minority groups. We examined whether the association between the VACS Index and neurocognition differed by ethnic/racial group. Participants included 674 HIV-infected individuals (369 non-Hispanic whites, 111 non-Hispanic blacks, and 194 Hispanics). Neurocognitive function was assessed via a comprehensive battery. Scaled scores for each neurocognitive test were averaged to calculate domain and global neurocognitive scores. Models adjusting for demographics and HIV disease characteristics not included in the VACS Index showed that higher VACS Index scores (indicating poorer health) were significantly associated with worse global neurocognition among non-Hispanic whites. This association was comparable in non-Hispanic blacks, but nonsignificant among Hispanics (with similar results for English and Spanish speaking). We obtained comparable findings in analyses adjusting for other covariates (psychiatric and medical comorbidities and lifestyle factors). Analyses of individual neurocognitive domains showed similar results in learning and delayed recall. For other domains, there was an effect of the VACS Index and no significant interactions with race/ethnicity. Different components of the VACS Index were associated with global neurocognition by race/ethnicity. In conclusion, the association between the VACS Index and neurocognitive function differs by ethnic/racial group. Identifying key indicators of HIV-associated neurocognitive impairment by ethnic/racial group might play an important role in furthering our understanding of the biomarkers of neuroAIDS.

Subtype associations with HIV-associated neurocognitive disorder in China

Factors associated with HIV-associated neurocognitive disorders (HAND) include CD4(+) nadir and count, HIV RNA level, and HIV-1 subtype. Here, we investigated demographical and clinical markers with respect to HAND in a homogenous Chinese population. Individuals with HAND (global deficit score ≥0.5) had lower nadir (p < 0.01) and CD4(+) counts (p = 0.03). HAND was also associated with AIDS (p < 0.01), but subtype was not (p = 0.198). Furthermore, worse impairment correlated with higher viral diversity (r = 0.16, p < 0.01), lower nadir (r = -0.17, p < 0.01), and CD4(+) counts (r = -0.11, p = 0.01). These remained significant even when correcting for subtype. Our findings suggest that subtype does not have a major impact on HAND.

Tuberculosis Containment among the Homeless in Metropolitan Jackson, Mississippi

IMPORTANCE

Preventing tuberculosis among the homeless has emerged as an especially difficult challenge.

OBJECTIVES

We assessed a 2008-2009 tuberculosis (TB) outbreak ad subsequent prevention strategies among homeless persons in metropolitan Jackson, Hinds County, Mississippi.

DESIGN, SETTING AND PARTICIPANTS

We compared data about cases and subclinical TB infections (LTBI) among homeless persons during the outbreak and post-outbreak years, interviewed involved homeless persons, compiled observations from visits to Jackson homeless shelters and conducted literature reviews on homelessness and infectious diseases. We reviewed homeless shelter TB prevention methods adopted by other municipalities, guidelines developed by the Centers for Disease Control and Prevention (CDC), and recommendations from other official and ad hoc groups and considered their applicability to metropolitan Jackson.

MAIN OUTCOMES AND MEASURES

The Mississippi State Department of Health TB Program assisted by the CDC and other agencies, contained the Jackson-area outbreak by the end of 2009 as reflected by progressively lower TB rates among homeless persons thereafter. However, some follow-up activities and enforcement of shelter preventive measures have not been consistently maintained. Resources to prevent further outbreaks continue to be inadequate, and over-reliance on private organizations has continued. In the process, appreciation of the dynamic interaction enhancing TB risk among the homeless and incarcerated persons has emerged.

RESULTS

Major outbreak contributors were lack of periodic TB screening among homeless shelter clients, preventive treatment compliance and follow-up difficulties among those with subclinical tuberculosis infections, interrupted preventive measures among infected persons incarcerated in local correctional facilities who disproportionately re-join Jackson's homeless community when released, inadequate attention to shelter environmental preventive strategies such as ultraviolet light germicidal irradiators and proper air-exchange/ventilation, costs of isolation housing for homeless people with full-blown tuberculosis (especially those co-infected with HIV and other infections and those with alcohol and/or other chemical dependencies), lack of adequate transportation which impacts access to evaluation and care, lack of mandated ongoing training among shelter and correctional facility staff, and inadequate attention to the societal problem of homelessness itself.

CONCLUSIONS

Sustained adherence to local shelter and correctional facility TB prevention measures based on standards and policies proved effective in other settings is most crucial. These include requirements for periodic tuberculosis prevention and awareness training for shelter and correctional facility staff, ongoing tuberculosis screening and follow-up among homeless shelter clients and inmates of local correctional facilities, and attention to shelter and correctional facility environmental sanitation, proper ventilation, ultraviolet light fixtures and capacity/bed alignment standards.

The effects of antiretroviral treatment initiation on cognition in HIV-infected individuals with advanced disease in Pune, India

There has been a reduction in the most severe cases of HIV-associated neurocognitive disorders (HAND) with advances in antiretroviral treatment (ART). But the prevalence of milder forms of HAND still remains high. Data from systematically conducted studies on the effects of ART on cognition are scanty in India, where HIV-1 clade C is prevalent. The purpose of the present study was to assess the effect of antiretroviral therapy in HIV-seropositive (HIV+) individuals (n = 92) with CD4 cell counts <200 cells/mm(3). The overall and domain-specific levels of cognitive functioning were determined using a locally recruited normative sample, and a change in neurocognitive functioning at the 1-year follow-up visit was analyzed. Results revealed cognitive impairment in 44.6 % of the HIV+ group at baseline. At the 1-year follow-up, the group showed significant improvement in the Learning domain (p < 0.05). HIV+ individuals showing improvement in the global cognitive scores had a significantly lower baseline CD4 cell count compared to others. Overall, the degree of improvement associated with the magnitude of rise in CD4 suggests the possibility that early, mild subclinical deficits may also benefit from treatment.

Persistent neurocognitive decline in a clinic sample of hepatitis C virus-infected persons receiving interferon and ribavirin treatment

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. Analyses were conducted to determine the prevalence of neurocognitive impairment over time; explicate the relationship between neurocognitive impairment, neuropsychiatric symptoms, and liver disease at each time point; and identify predictors of neurocognitive decline as well as cognitive effects of viral clearance. By 10 weeks after initiating IFN/RBV, the prevalence of neurocognitive impairment rose from 22.5 to 47.4% (p < 0.05). Infection with genotype 1 and premorbid depression were associated with more severe declines (p < 0.05). After 18 months, 42.5% remained neurocognitively impaired, independent of viral clearance, severity of liver disease, and current depressive symptoms. Undetectable viral load was not associated with improvement 18 months after initiating treatment (p > 0.10). Results of the current study indicate that IFN/RBV treatment-emergent neurocognitive declines are significant, prevalent, and may persist long after treatment cessation. Clinicians should monitor cognition throughout the course of treatment for HCV, noting that early declines may indicate individuals at elevated risk for persistent neurocognitive impairment. Longer-term studies are needed to determine whether lasting declines may remit over longer intervals or with newer direct acting agents.

Genetic variation in iron metabolism is associated with neuropathic pain and pain severity in HIV-infected patients on antiretroviral therapy

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. Genotype-DNP associations were explored by logistic regression and permutation-based analytical methods. Among 559 evaluable subjects, 331 (59%) developed HIV-SN, and 168 (30%) reported DNP. Fifteen polymorphisms in 8 genes (p<0.05) and 5 variants in 4 genes (p<0.01) were nominally associated with DNP: polymorphisms in TF, TFRC, BMP6, ACO1, SLC11A2, and FXN conferred reduced risk (adjusted odds ratios [ORs] ranging from 0.2 to 0.7, all p<0.05); other variants in TF, CP, ACO1, BMP6, and B2M conferred increased risk (ORs ranging from 1.3 to 3.1, all p<0.05). Risks associated with some variants were statistically significant either in black or white subgroups but were consistent in direction. ACO1 rs2026739 remained significantly associated with DNP in whites (permutation p<0.0001) after correction for multiple tests. Several of the same iron-regulatory-gene polymorphisms, including ACO1 rs2026739, were also associated with severity of DNP (all p<0.05). Common polymorphisms in iron-management genes are associated with DNP and with DNP severity in HIV-infected persons receiving cART. Consistent risk estimates across population subgroups and persistence of the ACO1 rs2026739 association after adjustment for multiple testing suggest that genetic variation in iron-regulation and transport modulates susceptibility to DNP.

Relationship of Medication Management Test-Revised (MMT-R) performance to neuropsychological functioning and antiretroviral adherence in adults with HIV

While performance-based tests of everyday functioning offer promise in facilitating diagnosis and classification of HIV-associated neurocognitive disorders (HAND), there remains a dearth of well-validated instruments. In the present study, clinical correlates of performance on one such measure (i.e., Medication Management Test-Revised; MMT-R) were examined in 448 HIV+ adults who were prescribed antiretroviral therapy. Significant bivariate relationships were found between MMT-R scores and demographics (e.g., education), hepatitis C co-infection, estimated premorbid IQ, neuropsychological functioning, and practical work abilities. MMT-R scores were not related to HIV disease severity, psychiatric factors, or self-reported adherence among participants with a broad range of current health status. However, lower MMT-R scores were strongly and uniquely associated with poorer adherence among participants with CD4 T cell counts <200. In multivariate analyses, MMT-R scores were predicted by practical work abilities, estimated premorbid functioning, attention/working memory, learning, and education. Findings provide overall mixed support for the construct validity of the MMT-R and are discussed in the context of their clinical and research implications for evaluation of HAND.

Effects of Marathi-Hindi bilingualism on neuropsychological performance

The present study aimed to examine if bilingualism affects executive functions and verbal fluency in Marathi and Hindi, two major languages in India, with a considerable cognate (e.g., activity is actividad in Spanish) overlap. A total of 174 native Marathi speakers from Pune, India, with varying levels of Hindi proficiency were administered tests of executive functioning and verbal performance in Marathi. A bilingualism index was generated using self-reported Hindi and Marathi proficiency. After controlling for demographic variables, the association between bilingualism and cognitive performance was examined. Degree of bilingualism predicted better performance on the switching (Color Trails-2) and inhibition (Stroop Color-Word) components of executive functioning; but not for the abstraction component (Halstead Category Test). In the verbal domain, bilingualism was more closely associated with noun generation (where the languages share many cognates) than verb generation (which are more disparate across these languages), as predicted. However, contrary to our hypothesis that the bilingualism "disadvantage" would be attenuated on noun generation, bilingualism was associated with an advantage on these measures. These findings suggest distinct patterns of bilingualism effects on cognition for this previously unexamined language pair, and that the rate of cognates may modulate the association between bilingualism and verbal performance on neuropsychological tests.

Neurocognitive impact of substance use in HIV infection

BACKGROUND

: To determine how serious a confound substance use (SU) might be in studies on HIV-associated neurocognitive disorder (HAND), we examined the relationship of SU history to neurocognitive impairment (NCI) in participants enrolled in the Central Nervous System HIV Antiretroviral Therapy Effects Research study.

METHODS

: After excluding cases with behavioral evidence of acute intoxication and histories of factors that independently could account for NCI (eg, stroke), baseline demographic, medical, SU, and neurocognitive data were analyzed from 399 participants. Potential SU risk for NCI was determined by the following criteria: lifetime SU Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition diagnosis, self-report of marked lifetime SU, or positive urine toxicology. Participants were divided into 3 groups as follows: no SU (n = 134), nonsyndromic SU (n = 131), syndromic SU (n = 134) and matched on literacy level, nadir CD4, and depressive symptoms.

RESULTS

: Although approximately 50% of the participants were diagnosed with HAND, a multivariate analysis of covariance of neurocogntive summary scores, covarying for urine toxicology, revealed no significant effect of SU status. Correlational analyses indicated weak associations between lifetime heroin dosage and poor recall and working memory and between cannabis and cocaine use and better verbal fluency.

CONCLUSIONS

: These data indicate that HIV neurocognitive effects are seen at about the same frequency in those with and without historic substance abuse in cases that are equated on other factors that might contribute to NCI. Therefore, studies on neuroAIDS and its treatment need not exclude such cases. However, the effects of acute SU and current SU disorders on HAND require further study.

Demographically corrected norms for African Americans and Caucasians on the Hopkins Verbal Learning Test-Revised, Brief Visuospatial Memory Test-Revised, Stroop Color and Word Test, and Wisconsin Card Sorting Test 64-Card Version

Memory and executive functioning are two important components of clinical neuropsychological (NP) practice and research. Multiple demographic factors are known to affect performance differentially on most NP tests, but adequate normative corrections, inclusive of race/ethnicity, are not available for many widely used instruments. This study compared demographic contributions for widely used tests of verbal and visual learning and memory (Brief Visual Memory Test-Revised, Hopkins Verbal Memory Test-Revised) and executive functioning (Stroop Color and Word Test, Wisconsin Card Sorting Test-64) in groups of healthy Caucasians (n = 143) and African Americans (n = 103). Demographic factors of age, education, gender, and race/ethnicity were found to be significant factors on some indices of all four tests. The magnitude of demographic contributions (especially age) was greater for African Americans than for Caucasians on most measures. New, demographically corrected T-score formulas were calculated for each race/ethnicity. The rates of NP impairment using previously published normative standards significantly overestimated NP impairment in African Americans. Utilizing the new demographic corrections developed and presented herein, NP impairment rates were comparable between the two race/ethnicities and were unrelated to the other demographic characteristics (age, education, gender) in either race/ethnicity group. Findings support the need to consider extended demographic contributions to neuropsychological test performance in clinical and research settings.