The impact of neurobehavioral features on medication adherence in HIV: evidence from longitudinal models

Does Social Support Play a Role in the Expression and Everyday Functioning Impact of Apathy in HIV Disease?

Clinically notable apathy occurs in approximately one-third of persons living with HIV (PLWH). Drawing from psychological theory, this cross-sectional study examined the interplay between apathy and social support in persons with (n = 143) and without (n = 61) HIV disease. Analyses were conducted using multiple regression and mediation procedures with 95th percentile bootstrap confidence intervals. Positive HIV serostatus and lower social support were associated with more frequent apathy, independent of other mood symptoms. Social support did not moderate apathy's associations with everyday functioning among PLWH, but post hoc analyses revealed that apathy mediated the relationship between social support and everyday functioning among PLWH. Stronger social support may provide a buffer against the frequency of apathy symptoms in persons with and without HIV disease. The relationship between lower social support and poorer everyday functioning in HIV might be partly explained by apathy. Longitudinal research is needed to examine the mechanisms of these relationships.

Apathy in persons living with HIV disease: A systematic narrative review

BACKGROUND

Apathy was identified as a feature of HIV early in the epidemic; however, there are no systematic reviews of the diverse literature on the sociodemographic and clinical correlates of apathy in HIV disease.

METHODS

The current study adopted a hybrid systematic-narrative review methodology in which we used PRISMA guidelines to identify, summarize, and critique peer-reviewed, empirical studies of apathy in HIV disease in the era of combination antiretroviral therapy.

RESULTS

A total of 34 studies of apathy in persons living with HIV (PLWH) were identified. Findings across these studies showed that apathy was reliably related to the structure of grey and white matter pathways commonly implicated in apathy, poorer everyday functioning, education, and other neuropsychiatric symptoms (e.g., depression). Apathy was not reliably associated with age, sex, race/ethnicity, cognition, and clinical markers of HIV disease.

LIMITATIONS

The current review does not provide rigorous quantitative estimates of clinical correlates of apathy, and the exclusion criteria of non-English and non-peer reviewed publications introduces risk of bias and Type I error.

CONCLUSIONS

Apathy occurs at higher rates in PLWH and is linked to neuroanatomical differences, as well as negative outcomes for everyday functions, aspects of neurocognition, and neuropsychiatric symptoms. As such, apathy is an important component to consider in the clinical assessment, diagnosis, and management of neurocognitive disorders in PLWH. Future work is needed to replicate existing findings with larger sample sizes and longitudinal designs, examine apathy as a multi-dimensional construct, and develop evidence-based treatments for apathy in PLWH.

Motivation levels and white matter microstructure in children living with HIV

Central nervous system involvement in HIV infection leads to neurobehavioural sequelae. Although apathy is a well-recognised symptom in adults living with HIV linked to alterations in brain structure, there is scarce research examining motivation in children living with HIV (CLWH). We used the Children's Motivation Scale (CMS; normative mean = 50, SD = 10) to assess motivation levels in 76 CLWH aged 6-16 years (63 on antiretroviral therapy [ART]; 13 ART-naïve slow progressors) in South Africa. Overall, CLWH scored low on the CMS (mean = 35.70 [SD = 5.87]). Motivation levels were significantly reduced in children taking ART compared to ART-naïve slow progressors (p = 0.02), but were not correlated with markers of HIV disease (CD4 + cell count or viral load), or neurocognitive function (p > 0.05). CMS scores were correlated with diffusion tensor imaging metrics of white matter microstructure in specific frontostriatal brain regions (p < 0.05). On multiple regression, associations with the anterior limb of the internal capsule, a subcortical white matter region, remained significant after adjusting for potential confounders. These findings suggest that reduced motivation may be an important neurobehavioural symptom in CLWH and may reflect changes in white matter microstructure of frontostriatal brain regions.

Microglia proliferation underlies synaptic dysfunction in the prefrontal cortex: implications for the pathogenesis of HIV-1-associated neurocognitive and affective alterations

Microglia, which are productively infected by HIV-1, are critical for brain development and maturation, as well as synaptic plasticity. The pathophysiology of HIV-infected microglia and their role in the pathogenesis of HIV-1-associated neurocognitive and affective alterations, however, remains understudied. Three complementary aims were undertaken to critically address this knowledge gap. First, the expression of HIV-1 mRNA in the dorsolateral prefrontal cortex of postmortem HIV-1 seropositive individuals with HAND was investigated. Utilization of immunostaining and/or RNAscope multiplex fluorescent assays revealed prominent HIV-1 mRNA in microglia of postmortem HIV-1 seropositive individuals with HAND. Second, measures of microglia proliferation and neuronal damage were evaluated in chimeric HIV (EcoHIV) rats. Eight weeks after EcoHIV inoculation, enhanced microglial proliferation was observed in the medial prefrontal cortex (mPFC) of EcoHIV rats, evidenced by an increased number of cells co-localized with both Iba1 + and Ki67 + relative to control animals. Neuronal damage in EcoHIV infected rats was evidenced by pronounced decreases in both synaptophysin and postsynaptic density protein 95 (PSD-95), markers of presynaptic and postsynaptic damage, respectively. Third, regression analyses were conducted to evaluate whether microglia proliferation mechanistically underlies neuronal damage in EcoHIV and control animals. Indeed, microglia proliferation accounted for 42-68.6% of the variance in synaptic dysfunction. Collectively, microglia proliferation induced by chronic HIV-1 viral protein exposure may underlie the profound synaptodendritic alterations in HIV-1. Understanding how microglia are involved in the pathogenesis of HAND and HIV-1-associated affective disorders affords a key target for the development of novel therapeutics.

Microglia Proliferation Underlies Synaptic Dysfunction in the Prefrontal Cortex: Implications for the Pathogenesis of HIV-1-Associated Neurocognitive and Affective Alterations

Microglia, which are productively infected by HIV-1, are critical for brain development and maturation, as well as synaptic plasticity. The pathophysiology of HIV-infected microglia and their role in the pathogenesis of HIV-1-associated neurocognitive and affective alterations, however, remains understudied. Three complementary aims were undertaken to critically address this knowledge gap. First, the predominant cell type expressing HIV-1 mRNA in the dorsolateral prefrontal cortex of postmortem HIV-1 seropositive individuals with HAND was investigated. Utilization of a combined RNAscope multiplex fluorescent and immunostaining assay revealed prominent HIV-1 mRNA in microglia of postmortem HIV-1 seropositive individuals with HAND. Second, measures of microglia proliferation and neuronal damage were evaluated in chimeric HIV (EcoHIV) rats. Eight weeks after EcoHIV innoculation, enhanced microglial proliferation was observed in the medial prefrontal cortex (mPFC) of EcoHIV rats, evidenced by an increased number of cells co-localized with both Iba1+ and Ki67+ relative to control animals. Neuronal damage in EcoHIV infected rats was evidenced by pronounced decreases in both synaptophysin and post synaptic density protein 95 (PSD-95), markers of pre-synaptic and post-synaptic damage, respectively. Third, regression analyses were conducted to evaluate whether microglia proliferation mechanistically underlies neuronal damage in EcoHIV and control animals. Indeed, microglia proliferation accounts for 42-68.6% of the variance in synaptic dysfunction. Collectively, microglia proliferation induced by chronic HIV-1 viral protein exposure may underlie the profound synaptodendritic alterations in HIV-1. Understanding how microglia are involved in the pathogenesis of HAND and HIV-1-associated affective disorders affords a key target for the development of novel therapeutics.

HIV-Associated Apathy/Depression and Neurocognitive Impairments Reflect Persistent Dopamine Deficits

Individuals living with human immunodeficiency virus type 1 (HIV-1) are often plagued by debilitating neurocognitive impairments and affective alterations;the pathophysiology underlying these deficits likely includes dopaminergic system dysfunction. The present review utilized four interrelated aims to critically examine the evidence for dopaminergic alterations following HIV-1 viral protein exposure. First, basal dopamine (DA) values are dependent upon both brain region andexperimental approach (i.e., high-performance liquid chromatography, microdialysis or fast-scan cyclic voltammetry). Second, neurochemical measurements overwhelmingly support decreased DA concentrations following chronic HIV-1 viral protein exposure. Neurocognitive impairments, including alterations in pre-attentive processes and attention, as well as apathetic behaviors, provide an additional line of evidence for dopaminergic deficits in HIV-1. Third, to date, there is no compelling evidence that combination antiretroviral therapy (cART), the primary treatment regimen for HIV-1 seropositive individuals, has any direct pharmacological action on the dopaminergic system. Fourth, the infection of microglia by HIV-1 viral proteins may mechanistically underlie the dopamine deficit observed following chronic HIV-1 viral protein exposure. An inclusive and critical evaluation of the literature, therefore, supports the fundamental conclusion that long-term HIV-1 viral protein exposure leads to a decreased dopaminergic state, which continues to persist despite the advent of cART. Thus, effective treatment of HIV-1-associated apathy/depression and neurocognitive impairments must focus on strategies for rectifying decreases in dopamine function.

Potentially undiagnosed cognitive impairment in patients with peripheral arterial disease: A systematic review of the literature

INTRODUCTION

It is purported that patients with peripheral arterial disease (PAD) may have impaired cognitive function due to concomitant cerebrovascular disease. Such disease may be clinically unrecognized but can impact on a patient's recovery and prognosis. The purpose of this systematic review was to interrogate the body of published evidence on undiagnosed cognitive impairment in PAD patients.

METHODS

A search strategy encompassing MEDLINE, Scopus, and the Cochrane database was developed to identify peer-reviewed articles examining rates of undiagnosed cognitive impairment in patients with PAD. The following search terms were used: 'PAD'; 'PVD'; 'dementia'; 'peripheral arterial disease'; 'peripheral vascular disease'; 'cognitive impairment'; 'alzheimer's disease' and 'cogniti∗'. Our primary outcome was the incidence of previously undiagnosed cognitive impairment in patients with PAD.

RESULTS

The initial search yielded 1492 titles. After removal of duplicates, 961 abstracts were screened to ascertain if they were eligible for inclusion. Abstract review yielded 62 full texts for further evaluation. Eight case-control studies consisting of 1161 patients were included. Analysis of these studies revealed that PAD patients performed significantly worse than controls on a variety of neuropsychological measures.

CONCLUSION

Our review indicated that PAD patients are more likely to suffer with undiagnosed cognitive impairment than healthy controls.

Apathy is Associated with Critical Psychological Determinants of Medication Adherence in HIV Disease

Apathy is common in HIV, separable from depression, and has been associated with non-adherence to antiretroviral therapy (ART). We examined the associations between apathy and critical psychological determinants of ART adherence, as per the information-motivation-behavioral model, in 85 persons living with HIV. Apathy was measured using a composite of the apathy subscale of the Frontal Systems Behavioral Scale and the vigor-activation scale of the Profile of Mood States. Independent of major depressive disorder, apathy was related at small-to-medium effect sizes with motivation to adhere and self-efficacy for health-related decision-making and medication management, but not with HIV knowledge or medication management skills. These findings suggest that apathy plays a unique role in several critical health adherence determinants and support the importance of assessment and management of apathy to maximize health outcomes among individuals with HIV disease.

Inhibitory control is associated with medication adherence in young HIV patients without comorbidities

OBJECTIVE

In the present study we evaluated the incremental contribution of executive cognition (EC) subprocesses to antiretroviral medication adherence.

METHOD

A comprehensive EC test battery assessing updating/working memory, mental flexibility, and inhibitory control, along with measures assessing non-executive cognitive functions were completed by 100 individuals with HIV. Medication adherence was determined via a visual analogue self-report scale and the Medication Adherence Questionnaire. Potential predictors, including demographic and clinical characteristics and neuropsychological performances on EC and other cognitive tasks were regressed to medication adherence. Predictive variables related to executive processes were added in the final block of the hierarchical regression model in order to assess their incremental predictive ability on medication adherence.

RESULTS

23% of the variance in the visual analogue scale was explained by treatment complexity, memory and EC performance. A measure of inhibitory control, in particular, predicted self-reported medication adherence above and beyond demographic, clinical and other cognitive factors.

CONCLUSIONS

The contribution of EC to self-reported medication adherence in young seropositive adults was limited, but inhibitory control was associated with proper medication management above and beyond demographic, clinical and other cognitive functions.

Cognitive Training: Associations and Implications for Weight Management and Translational Research

Behavioral weight loss programs combining energy restriction and increased physical activity (PA) are generally successful in producing clinically significant weight loss (≥5%) over 3-6 mos. However, weight maintenance (≥ 2 yrs.) continues to be problematic, due in part to an inability of individuals to continue adherence to diet and PA recommendations. It is hypothesized that neurocognitive processes, specifically executive functions (EFs, i.e., inhibition, working memory, mental flexibility), underlie self-regulation, self-efficacy, and are essential for the adoption and maintenance of health behaviors. Behavioral weight loss programs generally attempt to improve self-regulation; however, these skills are difficult to implement long-term. Strengthening EFs through cognitive training may improve weight maintenance by improving self-efficacy and self-regulation, resulting in improved program attendance and improved adherence to dietary and PA recommendations. Although randomized trials have not been conducted to specifically evaluate this hypothesis, results from the available literature suggest the potential for cognitive training to improve weight maintenance.

Association of self-reported executive function and mood with executive function task performance across adult populations

Executive function (EF) impacts behavior associated with health outcomes. EF can be measured using self-report and/or performance measures, but the correlations between these types of measures are mixed in the extant literature. This study examined self-report and performance-based measures of EF using data from 6 studies, including community and clinical populations (410 participants, ages 19-80, 71% female). Partial correlations revealed significant relationships between performance on the Trail making, Delay Discounting, and Stop Signal tasks with self-reported EF (p < .006 after controlling for age). Mood scores were significantly related to all self-reported domains of EF (p < .0001), and mood and EF scores were correlated over time. When also controlling for mood, correlations between delay discounting and stop signal tasks with self-reported EF remained significant (p < .006). Finally, examining EF scores in participants with and without clinically elevated mood scores showed a wider distribution of self-reported EF scores among those with clinically elevated mood symptoms than among those without. We conclude that self-reported EF is associated with tasks measuring delay discounting and response inhibition in our large, heterogenous population and that assessing EF may be particularly important for those with high levels of mood symptoms.

Mental Health and Functional Competence in the Cape Town Adolescent Antiretroviral Cohort

BACKGROUND

The impact of HIV and antiretrovirals (ART) on long-term mental health in perinatally infected children has not been well studied in sub-Saharan Africa where HIV is most prevalent.

SETTING

Cape Town, South Africa.

METHODS

We investigated mental health measures, including depression, anxiety, attention-deficit hyperactivity disorder, motivation, disruptive behavior, and functioning in perinatally infected adolescents (PHIV+) stable on ART within the Cape Town Adolescent Antiretroviral Cohort. Two hundred four adolescents living with HIV (median age 10 years; mean CD4 953) and a sample of 44 uninfected adolescents were enrolled. The Beck Youth Inventories, Children's Motivation Scale, Conner's Parent's Rating Scale, and Child Behavior Checklist were administered. Among PHIV+, we explored independent associations between HIV-related stigma, recent life stressors, sociodemographic, clinical, and caregiver-related variables, and mental health measures.

RESULTS

PHIV+ had poorer functional competence, self-concept and motivation, higher levels of disruptive behavior, depression and attention-deficit hyperactivity disorder symptoms and clinically significant anger and disruptive behavior. Within the PHIV+ group, the loss of both biological parents was associated with higher levels of disruptive behavior. Within the PHIV+, factors associated with mental health symptoms and poorer functioning were mostly sociodemographic factors, HIV-related stigma, and life stressors. Age of initiation of ART was associated with self-concept, and failing first-line ART with internalizing and externalizing behavior problems.

CONCLUSIONS

PHIV+ are likely to face future physical and psychological health consequences related to the functional competence challenges they face if mental health care is not made a priority in the fight against HIV.

Comorbid depression and apathy in HIV-associated neurocognitive disorders in the era of chronic HIV infection

This chapter provides an overview of the current research on the question of depression and apathy in HIV-associated neurocognitive disorders (HAND) in the era of chronic HIV infection. After presenting the epidemiology of each condition showing that depression and apathy are the two most frequent psychiatric comorbidities of HAND, we review the current research, particularly in relation to the milder forms of HAND that characterize treated HIV cohorts. Doing so, we include findings on depression and apathy in non-HIV aging population and the risk of dementia, findings that are relevant to the aging HIV cohorts carrying a high burden of psychiatric comorbidities. We then present a review of the research pertaining to the differentiation between depression and apathy. A section is dedicated to the question of suicidality in chronic HIV infection, which is underappreciated. An overview of the pharmacologic and psychosocial interventions relevant to depression and apathy in HIV cohorts treated with antiretroviral treatment is provided. The chapter concludes with future directions for the research on apathy and depression with emphasis on the question of aging and the need for longitudinal studies.

Synaptic Connectivity in Medium Spiny Neurons of the Nucleus Accumbens: A Sex-Dependent Mechanism Underlying Apathy in the HIV-1 Transgenic Rat

Frontal-subcortical circuit dysfunction is commonly associated with apathy, a neuropsychiatric sequelae of human immunodeficiency virus type-1 (HIV-1). Behavioral and neurochemical indices of apathy in the nucleus accumbens (NAc), a key brain region involved in frontal-subcortical circuitry, are influenced by the factor of biological sex. Despite evidence of sex differences in HIV-1, the effect of biological sex on medium spiny neurons (MSNs), which are central integrators of frontal-subcortical input, has not been systematically evaluated. In the present study, a DiOlistic labeling technique was used to investigate the role of long-term HIV-1 viral protein exposure, the factor of biological sex, and their possible interaction, on synaptic dysfunction in MSNs of the NAc in the HIV-1 transgenic (Tg) rat. HIV-1 Tg rats, independent of biological sex, displayed profound alterations in synaptic connectivity, evidenced by a prominent shift in the distribution of dendritic spines. Female HIV-1 Tg rats, but not male HIV-1 Tg rats, exhibited alterations in dendritic branching and neuronal arbor complexity relative to control animals, supporting an alteration in glutamate neurotransmission. Morphologically, HIV-1 Tg male, but not female HIV-1 Tg rats, displayed a population shift towards decreased dendritic spine volume, suggesting decreased synaptic area, relative to control animals. Synaptic dysfunction accurately identified presence of the HIV-1 transgene, dependent upon biological sex, with at least 80% accuracy (i.e., Male: 80%; Female: 90%). Collectively, these results support a primary alteration in circuit connectivity, the mechanism of which is dependent upon biological sex. Understanding the effect of biological sex on the underlying neural mechanism for HIV-1 associated apathy is vital for the development of sex-based therapeutics and cure strategies.

High early life stress and aberrant amygdala activity: risk factors for elevated neuropsychiatric symptoms in HIV+ adults

Relative to HIV-negative adults, HIV+ adults report elevated levels of early life stress (ELS). In non-HIV samples, high ELS has been linked to abnormalities in brain structure and function, as well as increased risk of neuropsychiatric symptoms. Yet, little is known about the neural effects of high ELS, and their relation to elevated neuropsychiatric symptoms, in HIV+ adults. Recent studies have revealed combined effects of HIV and high ELS on amygdala morphometry. Aberrant amygdala activity is prominently implicated in studies of neuropsychiatric symptomology in non-HIV samples. Hence, this preliminary study examined: 1) the combined effects of HIV and high ELS on amygdala activity, and 2) the relation between amygdala activity and neuropsychiatric symptoms in HIV+ adults. We included 28 HIV+ adults and 25 demographically-matched HIV-negative control (HC) adults. ELS exposure was quantified using a retrospective ELS questionnaire, which defined four groups: HIV+ Low-ELS (N = 15); HIV+ High-ELS (N = 13); HC Low-ELS (N = 16); and HC High-ELS (N = 9). Participants completed a battery of neuropsychiatric measures. BOLD fMRI assessed amygdala reactivity during explicit observation of fearful/angry faces. High-ELS participants demonstrated reduced levels of amygdala reactivity relative to Low-ELS participants. HIV+ High-ELS participants reported higher levels of neuropsychiatric symptoms than all other groups. In the HIV+ group, lower amygdala responses were associated with higher neuropsychiatric symptoms, particularly depression, anxiety, and alexithymia. Collectively, these results suggest that high ELS exposure is a significant risk factor for neuropsychiatric symptoms in HIV+ adults. Furthermore, our results implicate ELS-related abnormalities in amygdala activity in the etiology of neuropsychiatric symptoms in HIV+ adults.

Patient and Facility Correlates of Racial Differences in Viral Control for Black and White Veterans with HIV Infection in the Veterans Administration

Black persons with HIV are less likely than white persons to experience viral control even while in treatment. We sought to understand whether patient characteristics and site of care explain these differences using a cross-sectional analysis of medical records. Our cohort included 8779 black and 7836 white patients in the Veterans Administration (VA) health system with HIV who received antiretroviral medication during 2013. Our primary outcome, viral control, was defined as HIV serum RNA <200 copies/mL. We examined the degree to which racial differences in viral control are related to site of care, patient characteristics (demographics, HIV treatment history, comorbid conditions, time in care, and medication adherence), retention in care, and combination antiretroviral therapy (cART) adherence, using multi-variable logistic regression models. Compared to whites, blacks were younger and had lower CD4 counts, more comorbidities, lower retention in care, and poorer medication adherence. The odds of uncontrolled viral load were 2.02 (p < 0.001) for black relative to white patients without risk adjustment (15% vs. 8% uncontrolled viral load, respectively). The odds decreased to 1.83 (p < 0.001), 1.65 (p < 0.001), 1.62 (p < 0.001), and 1.24 (p = 0.01) in models that sequentially controlled for site of care, age and clinical characteristics, care retention, and cART adherence, respectively. Overall, 51% of the viral control difference between blacks and whites was accounted for by adherence; 26% by site of care. We conclude that differences in the site of HIV care and cART adherence account for most of the difference in viral control between black and white persons receiving HIV care, although the exact pathway by which this relationship occurs is unknown. Targeting poorer performing sites for quality improvement and focusing on improving antiretroviral adherence in black patients may help alleviate disparities in viral control.

Development and Validation of the Parkinson's Disease Medication Beliefs Scale (PD-Rx)

BACKGROUND

Medication non-adherence is common in Parkinson's disease (PD) and is associated with increased disability and healthcare costs. Individuals' beliefs regarding their medical conditions and treatments impact medication adherence. While instruments exist to measure patients' beliefs about medications in general, no such tool exists for PD.

OBJECTIVES

Create an instrument eliciting medication beliefs of persons with PD; identify demographic and clinical characteristics associated with beliefs; and examine whether beliefs are associated with dopaminergic therapy adherence.

METHODS

We developed the Parkinson's Disease Medication Beliefs Scale (PD-Rx) in four phases: focus groups of patients and caregivers to generate items, scale development, expert and patient revision of items, and a cross-sectional validation sample (n = 75). Adherence was calculated using two approaches incorporating self-reported medication lists.

RESULTS

The PD-Rx consists of 11 items covering benefits and risks of PD pharmacotherapies. The scale covers motor improvement, current adverse effects, and future concerns. Higher scores indicate more positive beliefs. Internal consistency was acceptable (Cronbach's alpha = 0.67). Test-retest reliability was 0.47. Quality of life was associated with PD-Rx scores, and lower scores were associated with non-adherence.

CONCLUSIONS

Negative beliefs about PD treatments are associated with lower quality of life and may be related to medication non-adherence. Further study of any causal relationship between beliefs and medication non-adherence in PD will inform the design of future patient-centered interventions to improve adherence.

Cannabis Use, Medication Management and Adherence Among Persons Living with HIV

Cannabis is used to relieve nausea, trigger weight gain, and reduce pain among adults living with HIV; however, the relationship between its use and medication adherence and management is unclear. Participants (N = 107) were from an ongoing cohort study of community-dwelling HIV+ adults, stratified by cannabis (CB) use: HIV+/CB+ (n = 41) and HIV+/CB- (n = 66). CB+ participants either tested positive in a urine toxicology screen for THC or had a self-reported history of regular and recent use. HIV-status was provided by physician results and/or biomarker assessment. Adherence was measured via the Morisky scale and medication management was assessed via the Medication Management Test-Revised. After adjusting for gender, we found no association between cannabis use group and adherence nor medication management. The amount of cannabis used was also not associated with measures of adherence and management. Preliminary findings suggest that cannabis use may not adversely influence medication adherence/management among adults living with HIV.

Psychosocial Correlates of Medication Adherence among HIV-Positive, Cognitively Impaired Individuals

Although cognitive impairment has been shown to adversely affect antiviral medication adherence, a subset of cognitively impaired adults nonetheless are able to adequately adhere to their medication regimen. However, little is known about factors that serve as buffers against suboptimal adherence among the cognitively impaired. This study consisted of 160 HIV-positive, cognitively impaired adults (Global Deficit Score ≥ 0.50) whose medication adherence was monitored over 6-months using an electronic monitoring device (MEMS caps). Logistic regressions were run to determine psychosocial variables associated with medication adherence. Higher self-efficacy and treatment related support, a stable medication regimen, stable stress levels, and absence of current stimulant use were predictive of optimal adherence. A distinct array of psychosocial factors was found that buffer against the adverse effects of cognitive impairment on medication adherence. Assessment and interventions targeting these factors may improve adherence rates among cognitively impaired adults.

Neurobehavioral Manifestations of Human Immunodeficiency Virus/AIDS: Diagnosis and Treatment

Behavioral disorders are common in persons infected with human immunodeficiency virus (HIV). The differential includes preexisting psychiatric diseases, substance abuse, direct effects of HIV infection, opportunistic infection, and the adverse effects of medical therapies. Many patients have more than one contributing or comorbid problem to explain these behavioral changes. The differential should always include consideration of psychosocial, genetic, and medical causes of disease. Treatment strategies must take into account the coadministration of antiretroviral therapy and the specific neurologic problems common in patients infected with HIV.

A Bidirectional Relationship between Executive Function and Health Behavior: Evidence, Implications, and Future Directions

Physically active lifestyles and other health-enhancing behaviors play an important role in preserving executive function into old age. Conversely, emerging research suggests that executive functions facilitate participation in a broad range of healthy behaviors including physical activity and reduced fatty food, tobacco, and alcohol consumption. They do this by supporting the volition, planning, performance monitoring, and inhibition necessary to enact intentions and override urges to engage in health damaging behavior. Here, we focus firstly on evidence suggesting that health-enhancing behaviors can induce improvements in executive function. We then switch our focus to findings linking executive function to the consistent performance of health-promoting behaviors and the avoidance of health risk behaviors. We suggest that executive function, health behavior, and disease processes are interdependent. In particular, we argue that a positive feedback loop may exist whereby health behavior-induced changes in executive function foster subsequent health-enhancing behaviors, which in turn help sustain efficient executive functions and good health. We conclude by outlining the implications of this reciprocal relationship for intervention strategies, the design of research studies, and the study of healthy aging.

Alexithymia, Assertiveness and Psychosocial Functioning in HIV: Implications for Medication Adherence and Disease Severity

Psychosocial function and adherence to antiretroviral regimen are key factors in human immunodeficiency virus (HIV) disease management. Alexithymia (AL) is a trait deficit in the ability to identify and describe feelings, emotions and bodily sensations. A structural equation model was used to test whether high levels of AL indirectly relate to greater non-adherent behavior and HIV disease severity via psychosocial dysfunction. Blood draws for HIV-1 viral load and CD4 T-lymphocyte, along with psychosocial surveys were collected from 439 HIV positive adults aged 18-73 years. The structural model supports significant paths from: (1) AL to non-active patient involvement, psychological distress, and lower social support, (2) psychological distress and non-active involvement to non-adherent behavior, and (3) non-adherence to greater HIV disease severity (CFI = .97, RMSEA = .04, SRMR = .05). A second model confirmed the intermediary effect of greater patient assertiveness on the path from AL to social support and non-active patient involvement (CFI = .94, RMSEA = .04, SRMR = .05). Altogether, AL is indirectly linked with HIV disease management through it's association with poor psychosocial function, however greater patient assertiveness buffers the negative impact of AL on relationship quality with healthcare providers and members of one's social support network.

HIV-1 Tat and cocaine mediated synaptopathy in cortical and midbrain neurons is prevented by the isoflavone Equol

Illicit drugs, such as cocaine, are known to increase the likelihood and severity of HIV-1 associated neurocognitive disorders (HAND). In the current studies synaptic integrity was assessed following exposure to low concentrations of the HIV-1 viral protein Tat 1-86B, with or without cocaine, by quantifying filamentous actin (F-actin) rich structures (i.e., puncta and dendritic spines) on neuronal dendrites in vitro. In addition, the synapse-protective effects of either R-Equol (RE) or S-Equol (SE; derivatives of the soy isoflavone, daidzein) were determined. Individually, neither low concentrations of HIV-1 Tat (10 nM) nor low concentrations of cocaine (1.6 μM) had any significant effect on F-actin puncta number; however, the same low concentrations of HIV-1 Tat + cocaine in combination significantly reduced dendritic synapses. This synaptic reduction was prevented by pre-treatment with either RE or SE, in an estrogen receptor beta dependent manner. In sum, targeted therapeutic intervention with SE may prevent HIV-1 + drug abuse synaptopathy, and thereby potentially influence the development of HAND.

Executive Function in Adults With Type 2 Diabetes: A Meta-Analytic Review

OBJECTIVE

To examine the extent to which Type 2 diabetes mellitus (T2DM) is associated with impairments in executive function (EF).

METHODS

Medline, PsychoInfo, and Scopus databases and published references were used to identify articles examining the association between T2DM status (case versus control) and EF decrements. Results from studies were converted to standardized mean differences and compared using random-effects models. Moderator analysis was conducted for age, sex, and diabetes duration using maximum likelihood estimation.

RESULTS

Sixty studies (59 articles) including 9815 individuals with T2DM and 69,254 controls were included. Findings indicated a small but reliable association between T2DM status and EF decrements (d = -0.248, p < .001), observed across all aspects of EF examined: verbal fluency, mental flexibility, inhibition, working memory, and attention. Disease duration significantly moderated the effect of T2DM status on EF.

CONCLUSIONS

T2DM is associated with a mild-to-moderate EF decrements. Such decrements are stronger among those with shorter disease duration.

Association between functional performance and executive cognitive functions in an elderly population including patients with low ankle-brachial index

Introduction

Peripheral arterial disease, as measured by the ankle–brachial index (ABI), is prevalent among the elderly, and is associated with functional performance, assessed by the 6-minute walk test (6MWT). Executive cognitive function (ECF) impairments are also prevalent in this population, but no existing study has investigated the association between ECF and functional performance in an elderly population including individuals with low ABI.

Aim

To investigate the association between functional performance, as measured by the 6MWT, and loss in ECF, in an elderly sample including individuals with low ABI.

Method

The ABI group was formed by 26 elderly individuals with low ABI (mean ABI: 0.63±0.19), and the control group was formed by 40 elderly individuals with normal ABI (mean ABI: 1.08±0.07). We analyzed functional performance using the 6MWT, global cognition using the Mini-Mental State Examination (MMSE), and ECF using the Digit Span for assessing attention span and working memory, the Stroop Color Word Test (SCWT) for assessing information processing speed and inhibitory control/impulsivity, and the Controlled Oral Word Association Test (COWAT) for assessing semantic verbal fluency and phonemic verbal fluency. We also used a factor analysis on all of the ECF tests (global ECF).

Results

Before adjustment, the ABI group performed worse on global cognition, attention span, working memory, inhibitory control/impulsivity, semantic verbal fluency, and phonemic verbal fluency. After adjustment, the ABI group performance remained worse for working memory and semantic verbal fluency. In a simple correlation analysis including all of the subjects, the 6MWT was associated with global cognition, attention span, working memory, information processing speed, inhibitory control/impulsivity, semantic verbal fluency, and global ECF. After adjustment, all the associations remained statistically significant.

Conclusion

This study found an independent association between functional performance and ECF in an elderly population including low ABI individuals, showing that, in elderly populations with functional impairment, ECF may also be impaired.

Neuropathological sequelae of Human Immunodeficiency Virus and apathy: A review of neuropsychological and neuroimaging studies

Apathy remains a common neuropsychiatric disturbance in the Human Immunodeficiency Virus (HIV-1) despite advances in anti-retroviral treatment (ART). The goal of the current review is to recapitulate findings relating apathy to the deleterious biobehavioral effects of HIV-1 in the post-ART era. Available literatures demonstrate that the emergence of apathy with other neurocognitive and neuropsychiatric symptoms may be attributed to neurotoxic effects of viral proliferation, e.g., aggregative effect of Tat and gp120 on apoptosis, transport and other enzymatic reactions amongst dopaminergic neurons and neuroglia. An assortment of neuroimaging modalities converge on the severity of apathy symptoms associated with the propensity of the virus to replicate within frontal-striatal brain circuits that facilitate emotional processing. Burgeoning research into functional brain connectivity also supports the effects of microvascular and neuro-inflammatory injury linked to aging with HIV-1 on the presentation of neuropsychiatric symptoms. Summarizing these findings, we review domains of HIV-associated neurocognitive and neuropsychiatric impairment linked to apathy in HIV. Taken together, these lines of research suggest that loss of affective, cognitive and behavioral inertia is commensurate with the neuropathology of HIV-1.

True durability: HIV virologic suppression in an urban clinic and implications for timing of intensive adherence efforts and viral load monitoring

Although the majority of HIV-infected patients who begin potent antiretroviral therapy should expect long-term virologic suppression, the realities in practice are less certain. Durability of viral suppression was examined to define the best timing of targeted adherence strategies and intensive viral load monitoring in an urban clinic population with multiple challenges to ART adherence. We examined the risk of viral rebound for patients who achieved two consecutive viral loads lower than the lower limit of quantification (LLOQ) within 390 days. For 791 patients with two viral loads below the LLOQ, viral rebound >LLOQ from the first viral load was 36.9 % (95 % CI 32.2-41.6) in the first year, 26.9 % (95 % CI 21.7-32.1) in the year following one year of viral suppression, and 24.6 % (95 % CI 18.4-30.9) in the year following 2 years of viral suppression. However, for patients with CD4 ≥300 cells/µl who had 3-6 years of virologic suppression, the risk of viral rebound was very low. At the population level, the risk of viral rebound in a complex urban clinic population is surprisingly high even out to 3 years. Intensified monitoring and adherence efforts should target this high risk period. Thereafter, confidence in truly durable virologic suppression is improved.

Interactive effects of neurocognitive impairment and substance use on antiretroviral non-adherence in HIV disease

While numerous studies have established the adverse independent effects of clinical conditions including neurocognitive dysfunction, psychiatric illness, and substance abuse/dependence on medication adherence among HIV-infected adults, fewer have studied their interactive effects. The current study examined this issue among 204 HIV-infected participants based upon current neurocognitive functioning and DSM-IV-diagnosed psychiatric illness and current substance abuse or dependence. Results confirmed that participants with any of these risk factors demonstrated poorer adherence than individuals with no risk factors. A neurocognitive status × substance abuse/dependence interaction was also identified such that participants with impaired neurocognition and a co-occurring substance abuse/dependence diagnosis demonstrated the poorest adherence. Results confirm the deleterious impact of these risk factors in isolation and also identify a specific interactive effect for individuals with comorbid neurocognitive impairment and a substance abuse/dependence disorder. Findings highlight the need for interventions that simultaneously address these problems.

The Montreal Cognitive Assessment: A Pilot Study of a Brief Screening Tool for Mild and Moderate Cognitive Impairment in HIV-Positive Veterans

HIV-associated neurocognitive disorders (HANDs) are common, often go undetected, and can impact treatment outcomes. There is limited evidence on how to perform routine cognitive screening in HIV clinical settings. To address this, 44 HIV-positive males were recruited from a Veteran Affairs Infectious Disease clinic and completed the Montreal Cognitive Assessment (MoCA), International HIV Dementia Scale (IHDS), and Depression Anxiety and Stress Scale-21. In all, 50% scored below the MoCA cutoff and 36% scored below the IHDS cutoff. Current CD4 was the strongest predictor of an abnormal MoCA score (P = .007, 95% confidence interval [CI]: 0.987-0.998) and elevated depression was the second strongest predictor (P = .008, CI: 1.043-1.326). Combination antiviral therapy use and age were not significant predictors in this model. The MoCA appeared to be a reasonable screening tool to detect cognitive impairment in HIV-positive patients, and although it is not sufficient to diagnose HAND, it has the potential to provide meaningful clinical data.

Host genetic factors predisposing to HIV-associated neurocognitive disorder

The success of combination antiretroviral therapy (cART) in transforming the lives of HIV-infected individuals with access to these drugs is tempered by the increasing threat of HIV-associated neurocognitive disorders (HAND) to their overall health and quality of life. Intensive investigations over the past two decades have underscored the role of host immune responses, inflammation, and monocyte-derived macrophages in HAND, but the precise pathogenic mechanisms underlying HAND remain only partially delineated. Complicating research efforts and therapeutic drug development are the sheer complexity of HAND phenotypes, diagnostic imprecision, and the growing intersection of chronic immune activation with aging-related comorbidities. Yet, genetic studies still offer a powerful means of advancing individualized care for HIV-infected individuals at risk. There is an urgent need for 1) longitudinal studies using consistent phenotypic definitions of HAND in HIV-infected subpopulations at very high risk of being adversely impacted, such as children, 2) tissue studies that correlate neuropathological changes in multiple brain regions with genomic markers in affected individuals and with changes at the RNA, epigenomic, and/or protein levels, and 3) genetic association studies using more sensitive subphenotypes of HAND. The NIH Brain Initiative and Human Connectome Project, coupled with rapidly evolving systems biology and machine learning approaches for analyzing high-throughput genetic, transcriptomic and epigenetic data, hold promise for identifying actionable biological processes and gene networks that underlie HAND. This review summarizes the current state of understanding of host genetic factors predisposing to HAND in light of past challenges and suggests some priorities for future research to advance the understanding and clinical management of HAND in the cART era.