Chin-Yuan Liang

Cognitive Performance Related to HIV-1-Infected Monocytes

The effect that HIV type 1 (HIV) has on neurocognition is a dynamic process whereby peripheral events are likely involved in setting the stage for clinical findings. In spite of antiretroviral therapy (ART), patients continue to be at risk for HIV-associated neurocognitive disorders (HAND), which might be related to persistence of inflammation. In a yearly assessment of HIV DNA levels in activated monocytes, increased HIV DNA copies were found in patients with persistent HAND. Furthermore, activated monocytes from patients with high HIV DNA copies secreted more inflammatory cytokines. Since these activated monocytes traffic to the CNS and enter the brain, they may contribute to an inflammatory environment in the CNS that leads to HAND.

Antiretroviral monocyte efficacy score linked to cognitive impairment in HIV.

BACKGROUND Monocytes transmigrating to the brain play a central role in HIV neuropathology. We hypothesized that the continued existence of neurocognitive impairment (NCI) despite potent antiretroviral (ARV) therapy is mediated by the inability of such therapy to control this monocyte/macrophage reservoir. METHODS Cross-sectional and longitudinal analyses were conducted within a prospectively enrolled cohort. We devised a monocyte efficacy (ME) score based on the anticipated effectiveness of ARV medications against monocytes/macrophages using published macrophage in vitro drug efficacy data. We examined, within an HIV neurocognitive database, its association with composite neuropsychological test scores (NPZ8) and clinical cognitive diagnoses among subjects on stable ARV medications unchanged for >6 months prior to assessment. RESULTS Among 139 subjects on ARV therapy, higher ME score correlated with better NPZ8 performance (r=0.23, P<0.01), whereas a score devised to quantify expected penetration effectiveness of ARVs into the brain (CPE score) did not (r=0.12, P=0.15). In an adjusted model (adjusted r(2)=0.12), ME score (β=0.003, P=0.02), CD4(+) T-cell nadir (β=0.001, P<0.01) and gender (β=-0.456, P=0.02) were associated with NPZ8, whereas CPE score was not (β=0.003, P=0.94). A higher ME score was associated with better clinical cognitive status (P<0.01). With a range of 12.5-433.0 units, a 100-unit increase in ME score resulted in a 10.6-fold decrease in the odds of a dementia diagnosis compared with normal cognition (P=0.01). CONCLUSIONS ARV efficacy against monocytes/macrophages correlates with cognitive function in HIV-infected individuals on ARV therapy within this cohort. If validated, efficacy against monocytes/macrophages may provide a new target to improve HIV NCI.

HIV DNA Reservoir Increases Risk for Cognitive Disorders in cART-Naïve Patients

Objectives Cognitive impairment remains frequent in HIV, despite combination antiretroviral therapy (cART). Leading theories implicate peripheral monocyte HIV DNA reservoirs as a mechanism for spread of the virus to the brain. These reservoirs remain present despite cART. The objective of this study was to determine if the level of HIV DNA in CD14+ enriched monocytes predicted cognitive impairment and brain injury. Methods We enrolled 61 cART-naïve HIV-infected Thais in a prospective study and measured HIV DNA in CD14+ enriched monocyte samples in a blinded fashion. We determined HAND diagnoses by consensus panel and all participants underwent magnetic resonance spectroscopy (MRS) to measure markers of brain injury. Immune activation was measured via cytokines in cerebrospinal fluid (CSF). Results The mean (SD) age was 35 (6.9) years, CD4 T-lymphocyte count was 236 (139) and log10 plasma HIV RNA was 4.8 (0.73). Twenty-eight of 61 met HAND criteria. The log10 CD14+ HIV DNA was associated with HAND in unadjusted and adjusted models (p = 0.001). There was a 14.5 increased odds ratio for HAND per 1 log-value of HIV DNA (10-fold increase in copy number). Plasma CD14+ HIV DNA was associated with plasma and CSF neopterin (p = 0.023) and with MRS markers of neuronal injury (lower N-acetyl aspartate) and glial dysfunction (higher myoinositol) in multiple brain regions. Interpretation Reservoir burden of HIV DNA in monocyte-enriched (CD14+) peripheral blood cells increases risk for HAND in treatment-naïve HIV+ subjects and is directly associated with CSF immune activation and both brain injury and glial dysfunction by MRS.

Impact of cerebrovascular disease on cognitive function in HIV-infected patients.

Cognitive dysfunction remains prevalent in the era of effective antiretroviral therapy. A recent study found that HIV-associated neurocognitive disorders (HAND) were present in 64% of HIV-infected individuals who were aviremic and without cognitive complaints.1 Such high rates of cognitive dysfunction are of major public health significance as even mild cognitive impairment may impair an individual’s ability to live independently and is associated with an increased mortality.2,3 The etiologies responsible for this continued cognitive dysfunction are likely multifactorial and may include persistent impairment that developed in the period predating use of effective antiretroviral therapy, on-going failure of current antiretroviral therapy (ARV) to effectively cross the blood brain barrier, toxicity of these medications, or the inability of these medications to fully suppress the effects of HIV per se among cells important to central nervous system (CNS) inflammation such as monocyte/macrophages, microglia or astrocytes.4 One alternative hypothesis is that etiologies responsible for cognitive dysfunction in the general population such as cerebrovascular disease (CVD) may also have an influence on cognition in this population. Multiple CVD risks such as glucose intolerance/diabetes, hypercholesterolemia, and hypertension are elevated in the HIV-population either due to the effect of HIV and/or to the impact of therapy. Several recent studies have demonstrated that poorer cognitive test performance in the HIV population is associated with vascular risk factors.5,6 The cognitive impact of CVD is presumably from the damage sustained from multiple microinfarcts particularly within the white and deep gray matter of the brain. It is now well established that CVD risk added to another degenerative disease process such as Alzheimer’s Disease is capable of accelerating the onset of otherwise subclinical disease to one with overt clinical functional consequences.7 Similar concerns may be valid in the context of HIV-associated cognitive dysfunction. CVD risk data was collected in the Hawaii Aging with HIV Cohort (HAHC) Study, a longitudinal cohort study assessing cognitive and neurologic outcomes in older HIV-infected individuals which has been detailed elsewhere.8 Briefly, 158 older (50 years of age or older) and 128 younger (20–39 years old) HIV-infected individuals were recruited between October 2001 to October 2005 with age, education, ethnicity, and gender-matched controls. Exclusion criteria included major neurologic or psychiatric illness, learning disability, major head injury, brain opportunistic infection, and primary language other than English. Baseline and annual evaluations included demographic data, medical/medication/substance abuse histories, neurologic examination, neuropsychological testing, and HIV laboratory parameters. The IRB at the University of Hawaii approved the study, and all subjects signed informed consent. Based on baseline data from a subset of 158 HIV+ and 123 HIV− age-, education-, and gender-matched HAHC subjects ≥ 50 years of age, we explored the differential effects of several CVD risk factors (diabetes, hypercholesterolemia, smoking and hypertension) on neuropsychological performance (NP) in HIV+ and HIV− subjects. Diabetes was defined by patient report of diagnosis, use of anti-diabetic medication, or fasting glucose ≥ 126 mg/dL. Hypercholesterolemia was defined by patient report of diagnosis, use of lipid-lowering agents, or fasting total cholesterol > 200 mg/dL. Smoking was defined as either current or past cigarette use, and hypertension based on prior diagnosis, use of anti-hypertensive medications, or resting BP ≥ 140/≥ 90 mm Hg. An extensive NP battery was performed, and age- and education-adjusted NP composite scores were calculated as previously described 9 to assess global cognitive function (NPZ8) and NP subdomains including psychomotor speed (NPZpm), motor function (NPZmotor), memory (NPZmem), and working memory/attention and concentration (NPZwmca) where a lower NPZ composite score implies worse cognitive impairment (see Figure legend for NP tests included in composite scores). The five NP composite scores (i.e., NPZ8, NPZpm, NPZmotor, NPZmem, NPZwmca) were used as the outcome. HIV-status and the addition of each CVD risk factor were considered separately (e.g., HIV-status and the presence or absence of diabetes; HIV-status and the presence or absence of hypercholesterolemia) in a multiple regression model to determine the effect of HIV and each individual CVD risk factor on NP. Mean age of HIV+ subjects was 55 years of age (standard deviation, SD = 5.3). A majority of these individuals were white (70%; 110/158), males (70%; 110/158) with at least a high school education (mean years of education = 14.6 years, SD 2.6 years). Seventy five percent of HIV+ subjects were treated with highly active antiretroviral therapy (HAART) and about half of these individuals (54%) had undetectable plasma HIV RNA viral load. Mean log10 HIV viral load was 2.6 copies/mL (SD, 1.3) with a mean CD4 count of 477 cells/uL (SD, 257) and nadir CD4 count of 202 cells/uL (SD, 166). In the HIV+ group, the prevalence of CVD risk factors were as follows: 70% were current or prior smokers, 45% had hypertension, 37% had hypercholesterolemia, and 11% had diabetes. There were no statistically significant differences in frequencies of smoking history and hypertension between HIV+ and HIV− groups. Hypercholesterolemia and diabetes were more prevalent in the HIV+ group. Most groups tended to perform below the mean for age- and education-matched controls from published normative data (Figure). Multiple regression analyses revealed that HIV (p = 0.006), diabetes (p = 0.021), and tobacco use (p = 0.005) were independent predictors of global cognitive function (NPZ8) with an adjusted R2 = 0.05. HIV (p = 0.007), diabetes (p = 0.008), and tobacco use (p = 0.004) were independent predictors of motor function (NPZmotor) with an adjusted R2 = 0.05. HIV (p = 0.001) and hypertension (p = 0.039) were independent predictors of working memory, concentration, and attention (NPZwmca) with an adjusted R2 = 0.06. If HIV-status was fixed, subjects who used tobacco would be expected to score 0.27 standard deviations lower on NPZ8 and 0.27 standard deviations lower on NPZmotor compared to non-smokers. If HIV-status was fixed, subjects with diabetes would score 0.40 standard deviations lower on NPZ8 and 0.45 standard deviations lower on NPZmotor compared to non-diabetics. Subjects with hypertension would score 0.18 standard deviations lower on NPZwmca compared to those without hypertension with HIV-status fixed. There were no significant interactions between HIV and CVD risk factors for any composite NP score. Subjects with multiple CVD risk factors were associated with worse global cognitive performance (p = 0.027). CVD risk factors were not optimally collected and is a limitation of our study. For example, the components of total cholesterol (i.e., LDL and HDL) were not obtained, and the diagnosis of diabetes was made by self-report. Thus, our results may underestimate the effect of diabetes and cholesterol on NP. Nevertheless, several interesting observations and conclusions are possible. As expected, our data showed that CVD risk factors worsen NP performance both in HIV+ and HIV− subjects. Our limited dataset suggests that CVD have an additive rather than synergistic effect on cognitive performance. Although the modest decreases in NP performance found in our cross-sectional analysis may not result in clinically significant interruptions of activities of daily living or observable deficiencies during a routine clinic visit, this finding is clinically important however since over time, the presence of CVD added to HIV-associated subclinical NP deficits may lead to overt functional cognitive problems. CVD risk factors are treatable with lifestyle modifications and anti-hypertensive, anti-diabetic, and lipid-lowering medications. Increased efforts to control CVD risk factors in the HIV-infected population are warranted.

Determinants of epidermal nerve fibre density in antiretroviral-naïve HIV-infected individuals.

Distal leg epidermal nerve fibre density (ENFD) is a validated predictor of small unmyelinated nerve fibre damage and neuropathy risk in HIV infection. As pre‐existing damage may increase the risk of neuropathy following antiretroviral (ARV) therapy, particularly when the regimen contains stavudine (d4T), we assessed the relationship between ENFD and various parameters including mitochondrial factors in HIV‐infected Thai individuals naïve to ARV therapy.

Different Levels of HIV DNA Copy Numbers in Cerebrospinal Fluid Cellular Subsets

Inequities in the incidence of HIV infection and AIDS with continued persistence of HIV-associated neurocognitive disorders (HAND) exist in populations in Hawaii (HI) and Puerto Rico (PR). We previously reported that peripheral monocyte HIV DNA levels are high in patients in Hawaii with HAND and we now hypothesize that similar findings would be observed in the cerebrospinal fluid (CSF) cellular subsets. Cerebrospinal fluid cells were obtained from patients from PR and HI undergoing neurocognitive testing and sorted into monocytes (CD14+) and lymphocytes (CD14-) and HIV DNA was measured. From six PR subjects (three HAND, three normal cognition, NC) and six HI subjects (three HAND, three NC), HIV DNA burden in CD14+ cells was higher in HAND than NC patients; NC patients had higher HIV DNA burden in CD14-cells versus HAND. Differences in HIV DNA burden in particular CSF cellular subsets suggest that HIV DNA burden may play a role in HAND neuropathogenesis.

Correction: HIV DNA Reservoir Increases Risk for Cognitive Disorders in cART-Naïve Patients

There were errors in multiple affiliations for multiple authors. Please see the following correct list of authors and affiliations: Victor G. Valcour 1,2*,Jintanat Ananworanich, 3,4,5,6, Melissa Agsalda 6, Napapon Sailasuta 7, Thep Chalermchai 3, Alexandra Schuetz 8, Cecilia Shikuma 6, Chin-Yuan Liang 6, Supunee Jirajariyavej 9, Pasiri Sithinamsuwan 10, Somporn Tipsuk 3, David B. Clifford 11, Robert Paul 12, James L. K. Fletcher 3, Mary A. Marovich 13, Bonnie M. Slike 14, Victor DeGruttola 15, Bruce Shiramizu 6 1. Memory and Aging Center, Department of Neurology, University of California, San Francisco, CA USA 2. Division of Geriatric Medicine, Department of Medicine, University of California, San Francisco CA, USA 3. SEARCH, Thai Red Cross AIDS Research Centre, Bangkok, Thailand 4. HIV-NAT, Thai Red Cross AIDS Research Center, Bangkok, Thailand 5. Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand 6. Hawaii Center for AIDS, University of Hawaii, Honolulu HI USA 7. Huntington Medical Research Institutes, Pasadena CA USA 8. Department of Retrovirology, Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand 9. Taksin Hospital, Bangkok, Thailand 10. Division of Neurology, Department of Medicine, Phramongkutklao Hospital, Bangkok, Thailand 11. Department of Neurology, Washington University, St. Louis MO USA 12. Department of Psychology, University of Missouri, St. Louis MO, USA 13. Division of AIDS, National Institute of Allergy and Infection Diseases of the National Institutes of Health, Bethesda MD, USA 14. US Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring MD, USA 15. Department of Biostatistics, Harvard School of Public Health, Boston MA, USA

A Community-Based Approach to Enhancing Anal Cancer Screening in Hawaii's HIV-Infected Ethnic Minorities

OBJECTIVE Disparities in anal cancer incidence among Hawaiis HIV-infected minority population is an emerging health concern. Although anal cytology/anoscopy are effective anal cancer screening tools, social barriers exist that prevent individuals from seeking appropriate care. DESIGN Community based participatory research (CBPR) principles were applied to develop resources, including testing a self-obtained anal specimen procedure, to increase anal cancer screening among Hawaiis underserved/ minority populations. METHODS A team of community members, academic researchers, and health care providers developed culturally-sensitive educational/recruitment materials regarding anal cancer risk targeting underserved/minority HIV-infected individuals. Self- and health care provider (HCP)-obtained anal cancer screening specimens were reviewed for cytology and tested for human papillomavirus DNA. A follow-up evaluation elicited feedback on attitudes and experiences. RESULTS Community discussion sessions identified key messages about anal cancer, anal cancer screening, and HPV infection for materials and were used, that successfully recruited 46 individuals (38 males/8 females; 9 Native Hawaiians/Pacific Islanders/Asians, 2 Blacks, 6 Hispanics, 6 American Indian/Alaskan Natives, 23 Whites). Concordance in cytology results between self- and HCP-obtained specimens was moderated (kappa=0.37) with the perception that the self-obtained specimen procedure was private (93%), safe (100%), and easy to manage (100%); and a majority (92%) willing to use the self-obtained method again. CONCLUSIONS CBPR was a practical approach in engaging Hawaiis HIV-infected minority participation in anal cancer screening research. Community outreach and recruitment efforts suggested that self-obtained screening specimens could be an acceptable and effective means to reach Hawaiis HIV-infected ethnic minorities.

Anal HIV DNA is associated with high-risk HPV genotypes in anal cytology specimens obtained for anal neoplasia screening

Purpose High-grade anal neoplasia (AN) is associated with highrisk human papillomavirus (HPV) genotypes and is the precursor to anal cancer. Individuals infected with human immunodeficiency virus type 1 (HIV) continue to be at increased risk for AN even while on effective antiretroviral therapy (ART) with undetectable HIV RNA levels. The study was undertaken to assess HIV DNA from anal cytology specimens to determine if HIV DNA copy number was a factor for presence of high risk HPV genotypes.