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Featured researches published by Igor Grant.


Neurology | 2010

HIV-associated neurocognitive disorders persist in the era of potent antiretroviral therapy: CHARTER Study.

Robert K. Heaton; David B. Clifford; Donald R. Franklin; Steven Paul Woods; Christopher F. Ake; Florin Vaida; Ronald J. Ellis; S. Letendre; Thomas D. Marcotte; Atkinson Jh; M. Rivera-Mindt; Ofilio Vigil; Michael J. Taylor; Ann C. Collier; C. M. Marra; Benjamin B. Gelman; Justin C. McArthur; Susan Morgello; David M. Simpson; McCutchan Ja; Ian Abramson; Anthony Gamst; Christine Fennema-Notestine; Terry L. Jernigan; Joseph K. Wong; Igor Grant

Objectives: This is a cross-sectional, observational study to determine the frequency and associated features of HIV-associated neurocognitive disorders (HAND) in a large, diverse sample of infected individuals in the era of combination antiretroviral therapy (CART). Methods: A total of 1,555 HIV-infected adults were recruited from 6 university clinics across the United States, with minimal exclusions. We used standardized neuromedical, psychiatric, and neuropsychological (NP) examinations, and recently published criteria for diagnosing HAND and classifying 3 levels of comorbidity (minimal to severe non-HIV risks for NP impairment). Results: Fifty-two percent of the total sample had NP impairment, with higher rates in groups with greater comorbidity burden (40%, 59%, and 83%). Prevalence estimates for specific HAND diagnoses (excluding severely confounded cases) were 33% for asymptomatic neurocognitive impairment, 12% for mild neurocognitive disorder, and only 2% for HIV-associated dementia (HAD). Among participants with minimal comorbidities (n = 843), history of low nadir CD4 was a strong predictor of impairment, and the lowest impairment rate on CART occurred in the subset with suppressed plasma viral loads and nadir CD4 ≥200 cells/mm3 (30% vs 47% in remaining subgroups). Conclusions: The most severe HAND diagnosis (HAD) was rare, but milder forms of impairment remained common, even among those receiving CART who had minimal comorbidities. Future studies should clarify whether early disease events (e.g., profound CD4 decline) may trigger chronic CNS changes, and whether early CART prevents or reverses these changes.


Journal of NeuroVirology | 2011

HIV-associated neurocognitive disorders before and during the era of combination antiretroviral therapy: differences in rates, nature, and predictors.

Robert K. Heaton; Donald R. Franklin; Ronald J. Ellis; J. Allen McCutchan; Scott Letendre; Shannon LeBlanc; Stephanie H. Corkran; Nichole A. Duarte; David B. Clifford; Steven Paul Woods; Ann C. Collier; Christina M. Marra; Susan Morgello; Monica Rivera Mindt; Michael J. Taylor; Thomas D. Marcotte; J. Hampton Atkinson; Tanya Wolfson; Benjamin B. Gelman; Justin C. McArthur; David M. Simpson; Ian Abramson; Anthony Gamst; Christine Fennema-Notestine; Terry L. Jernigan; Joseph K. Wong; Igor Grant

Combination antiretroviral therapy (CART) has greatly reduced medical morbidity and mortality with HIV infection, but high rates of HIV-associated neurocognitive disorders (HAND) continue to be reported. Because large HIV-infected (HIV+) and uninfected (HIV−) groups have not been studied with similar methods in the pre-CART and CART eras, it is unclear whether CART has changed the prevalence, nature, and clinical correlates of HAND. We used comparable methods of subject screening and assessments to classify neurocognitive impairment (NCI) in large groups of HIV + and HIV − participants from the pre-CART era (1988–1995; N = 857) and CART era (2000–2007; N = 937). Impairment rate increased with successive disease stages (CDC stages A, B, and C) in both eras: 25%, 42%, and 52% in pre-CART era and 36%, 40%, and 45% in CART era. In the medically asymptomatic stage (CDC-A), NCI was significantly more common in the CART era. Low nadir CD4 predicted NCI in both eras, whereas degree of current immunosuppression, estimated duration of infection, and viral suppression in CSF (on treatment) were related to impairment only pre-CART. Pattern of NCI also differed: pre-CART had more impairment in motor skills, cognitive speed, and verbal fluency, whereas CART era involved more memory (learning) and executive function impairment. High rates of mild NCI persist at all stages of HIV infection, despite improved viral suppression and immune reconstitution with CART. The consistent association of NCI with nadir CD4 across eras suggests that earlier treatment to prevent severe immunosuppression may also help prevent HAND. Clinical trials targeting HAND prevention should specifically examine timing of ART initiation.


Biological Psychiatry | 2005

Mood Disorders in the Medically Ill: Scientific Review and Recommendations

Dwight L. Evans; Dennis S. Charney; Lydia Lewis; Robert N. Golden; Jack M. Gorman; K. Ranga Rama Krishnan; Charles B. Nemeroff; J. Douglas Bremner; Robert M. Carney; James C. Coyne; Mahlon R. DeLong; Nancy Frasure-Smith; Alexander H. Glassman; Philip W. Gold; Igor Grant; Lisa P. Gwyther; Gail Ironson; Robert L. Johnson; Andres M. Kanner; Wayne Katon; Peter G. Kaufmann; Francis J. Keefe; Terence A. Ketter; Thomas Laughren; Jane Leserman; Constantine G. Lyketsos; William M. McDonald; Bruce S. McEwen; Andrew H. Miller; Christopher M. O'Connor

OBJECTIVE The purpose of this review is to assess the relationship between mood disorders and development, course, and associated morbidity and mortality of selected medical illnesses, review evidence for treatment, and determine needs in clinical practice and research. DATA SOURCES Data were culled from the 2002 Depression and Bipolar Support Alliance Conference proceedings and a literature review addressing prevalence, risk factors, diagnosis, and treatment. This review also considered the experience of primary and specialty care providers, policy analysts, and patient advocates. The review and recommendations reflect the expert opinion of the authors. STUDY SELECTION/DATA EXTRACTION Reviews of epidemiology and mechanistic studies were included, as were open-label and randomized, controlled trials on treatment of depression in patients with medical comorbidities. Data on study design, population, and results were extracted for review of evidence that includes tables of prevalence and pharmacological treatment. The effect of depression and bipolar disorder on selected medical comorbidities was assessed, and recommendations for practice, research, and policy were developed. CONCLUSIONS A growing body of evidence suggests that biological mechanisms underlie a bidirectional link between mood disorders and many medical illnesses. In addition, there is evidence to suggest that mood disorders affect the course of medical illnesses. Further prospective studies are warranted.


JAMA Neurology | 2008

Validation of the CNS Penetration-Effectiveness Rank for Quantifying Antiretroviral Penetration Into the Central Nervous System

Scott Letendre; Jennifer Marquie-Beck; Edmund V. Capparelli; Brookie M. Best; David B. Clifford; Ann C. Collier; Benjamin B. Gelman; Justin C. McArthur; J. Allen McCutchan; Susan Morgello; David M. Simpson; Igor Grant; Ronald J. Ellis

OBJECTIVE To evaluate whether penetration of a combination regimen into the central nervous system (CNS), as estimated by the CNS Penetration-Effectiveness (CPE) rank, is associated with lower cerebrospinal fluid (CSF) viral load. DESIGN Data were analyzed from 467 participants who were human immunodeficiency virus (HIV) seropositive and who reported antiretroviral (ARV) drug use. Individual ARV drugs were assigned a penetration rank of 0 (low), 0.5 (intermediate), or 1 (high) based on their chemical properties, concentrations in CSF, and/or effectiveness in the CNS in clinical studies. The CPE rank was calculated by summing the individual penetration ranks for each ARV in the regimen. RESULTS The median CPE rank was 1.5 (interquartile range, 1-2). Lower CPE ranks correlated with higher CSF viral loads. Ranks less than 2 were associated with an 88% increase in the odds of detectable CSF viral load. In multivariate regression, lower CPE ranks were associated with detectable CSF viral loads even after adjusting for total number of ARV drugs, ARV drug adherence, plasma viral load, duration and type of the current regimen, and CD4 count. CONCLUSIONS Poorer penetration of ARV drugs into the CNS appears to allow continued HIV replication in the CNS as indicated by higher CSF HIV viral loads. Because inhibition of HIV replication in the CNS is probably critical in treating patients who have HIV-associated neurocognitive disorders, ARV treatment strategies that account for CNS penetration should be considered in consensus treatment guidelines and validated in clinical studies.


Journal of The International Neuropsychological Society | 1995

The HNRC 500-Neuropsychology of Hiv infection at different disease stages

Robert K. Heaton; Igor Grant; Nelson Butters; Desiree A. White; Kirson D; J. Hampton Atkinson; J. Allen McCutchan; Michael J. Taylor; Mark D. Kelly; Ronald J. Ellis; Tanya Wolfson; Robert A. Velin; Thomas D. Marcotte; John R. Hesselink; Terry L. Jernigan; James L. Chandler; Mark S. Wallace; Ian Abramson

The present study examined neuropsychological (NP) functioning and associated medical, neurological, brain magnetic resonance imaging (MRI), and psychiatric findings in 389 nondemented males infected with Human Immunodeficiency Virus-Type 1 (HIV-1), and in 111 uninfected controls. Using a comprehensive NP test battery, we found increased rates of impairment at each successive stage of HIV infection. HIV-related NP impairment was generally mild, especially in the medically asymptomatic stage of infection, and most often affected attention, speed of information processing, and learning efficiency; this pattern is consistent with earliest involvement of subcortical or frontostriatal brain systems. NP impairment could not be explained on the bases of mood disturbance, recreational drug or alcohol use, or constitutional symptoms; by contrast, impairment in HIV-infected subjects was related to central brain atrophy on MRI, as well as to evidence of cellular immune activation and neurological abnormalities linked to the central nervous system.


Annals of Internal Medicine | 1987

Evidence for Early Central Nervous System Involvement in the Acquired Immunodeficiency Syndrome (AIDS) and Other Human Immunodeficiency Virus (HIV) Infections: Studies with Neuropsychologic Testing and Magnetic Resonance Imaging

Igor Grant; J. Hampton Atkinson; John R. Hesselink; Caroline J. Kennedy; Douglas D. Richman; Stephen A. Spector; J. Allen McCutchan

Although a high prevalence of central nervous system disease is seen in persons with the acquired immunodeficiency syndrome (AIDS), the natural history of brain involvement with human immunodeficiency virus (HIV) remains poorly understood. Neuropsychologic evaluations of 55 ambulatory homosexual men revealed abnormalities in 13 of 15 with AIDS, 7 of 13 [corrected] with AIDS-related complex, 7 of 16 [corrected] with HIV-seropositivity only, and 1 of 11 with HIV-seronegativity. Common neuropsychologic problems included impaired abstracting ability, learning difficulties, and slowed speed of information processing. Magnetic resonance imaging had abnormal findings in 9 of 13 patients with AIDS and 5 of 10 patients with AIDS-related complex who were available for scans. The commonest abnormalities were sulcal and ventricular enlargement and bilateral patchy areas of high signal intensity in the white matter. We postulate that central nervous system involvement by HIV may begin early in the course of AIDS and cause mild cognitive deficits in otherwise asymptomatic persons.


Neuropsychology Review | 2007

Neurocognitive effects of methamphetamine: a critical review and meta-analysis.

J. Cobb Scott; Steven Paul Woods; Georg E. Matt; Rachel Meyer; Robert K. Heaton; J. Hampton Atkinson; Igor Grant

This review provides a critical analysis of the central nervous system effects of acute and chronic methamphetamine (MA) use, which is linked to numerous adverse psychosocial, neuropsychiatric, and medical problems. A meta-analysis of the neuropsychological effects of MA abuse/dependence revealed broadly medium effect sizes, showing deficits in episodic memory, executive functions, information processing speed, motor skills, language, and visuoconstructional abilities. The neuropsychological deficits associated with MA abuse/dependence are interpreted with regard to their possible neural mechanisms, most notably MA-associated frontostriatal neurotoxicity. In addition, potential explanatory factors are considered, including demographics (e.g., gender), MA use characteristics (e.g., duration of abstinence), and the influence of common psychiatric (e.g., other substance-related disorders) and neuromedical (e.g., HIV infection) comorbidities. Finally, these findings are discussed with respect to their potential contribution to the clinical management of persons with MA abuse/dependence.


Journal of The International Neuropsychological Society | 1999

Test-retest reliability and practice effects of expanded Halstead-Reitan Neuropsychological Test Battery.

Sureyya Dikmen; Robert K. Heaton; Igor Grant; Nancy Temkin

Test-retest reliabilities and practice effects of a broad range of neuropsychological measures were examined in 384 normal or neurologically stable adults. Median test-retest interval was 11 months (range 3-16 months). The reliability estimates for most of the measures are reasonably good, ranging from .70 to low .90s. An exception is the relatively poor reliabilities of most memory measures. For all test measures, the value on initial testing is a strong determinant of the value on the second examination. Practice effects are seen on most measures. The magnitude of the practice effects, however, varies as a function of type of measure, test-retest interval, age, and overall competency level of the participant. This study provides several types of retest information that may be useful for future research and clinical work: comparative reliabilities of the various measures, estimate of error variability associated with each administration, standard deviation of the change, and comparative magnitude of practice effects on various tests.


Journal of The International Neuropsychological Society | 2004

Methamphetamine dependence increases risk of neuropsychological impairment in HIV infected persons

Julie D. Rippeth; Robert K. Heaton; Catherine L. Carey; Thomas D. Marcotte; David Moore; Raul Gonzalez; Tanya Wolfson; Igor Grant

Both HIV infection and methamphetamine dependence can be associated with brain dysfunction. Little is known, however, about the cognitive effects of concurrent HIV infection and methamphetamine dependence. The present study included 200 participants in 4 groups: HIV infected/methamphetamine dependent (HIV+/METH+), HIV negative/methamphetamine dependent (HIV-/METH+), HIV infected/methamphetamine nondependent (HIV+/METH-), and HIV negative/methamphetamine nondependent (HIV-/METH-). Study groups were comparable for age, education, and ethnicity, although the HIV-/METH- group had significantly more females. A comprehensive, demographically corrected neuropsychological battery was administered yielding a global performance score and scores for seven neurobehavioral domains. Rates of neuropsychological impairment were determined by cutoff scores derived from performances of a separate control group and validated with larger samples of HIV+ and HIV- participants from an independent cohort. Rates of global neuropsychological impairment were higher in the HIV+/METH+ (58%), HIV-/METH+ (40%) and HIV+/METH- (38%) groups compared to the HIV-/METH- (18%) group. Nonparametric analyses revealed a significant monotonic trend for global cognitive status across groups, with least impairment in the control group and highest prevalence of impairment in the group with concurrent HIV infection and methamphetamine dependence. The results indicate that HIV infection and methamphetamine dependence are each associated with neuropsychological deficits, and suggest that these factors in combination are associated with additive deleterious cognitive effects. This additivity may reflect common pathways to neural injury involving both cytotoxic and apoptotic mechanisms.


Journal of Clinical Epidemiology | 1988

A CHINESE VERSION OF THE MINI-MENTAL STATE EXAMINATION; IMPACT OF ILLITERACY IN A SHANGHAI DEMENTIA SURVEY

Robert Katzman; Mingyuan Zhang; Ouang-Ya-Qu; Zheng-Yu Wang; William T. Liu; Elena Yu; Sin-Chi Wong; David P. Salmon; Igor Grant

A dementia screening survey was carried out in Shanghai using a culturally adapted Chinese version of the Mini-Mental State Examination. A probability sample of 5055 community-dwelling elderly in Shanghai was surveyed, 1497 aged 55-64, 2187 aged 65-74, and 1371 aged 75 and over. In the 73.3% of the subjects who had gone to school, using the age and education adjustments suggested by Kittner et al. (1986), [Kittner et al. J Chron Dis 39: 163-170; 1986] suitable cutoff scores could readily be selected to identify the subjects who should be examined intensively for the presence of dementia. However, in the 26.7% who had not gone to school, there was a significant increase in low scores on the mental status test as well as a different error pattern, reflecting the lack of formal education. Methods for following cognitive changes in illiterate individuals need further development.

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Thomas L. Patterson

Henry M. Jackson Foundation for the Advancement of Military Medicine

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Scott Letendre

University of California

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J. Hampton Atkinson

United States Department of Veterans Affairs

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Paul J. Mills

University of California

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Benjamin B. Gelman

University of Texas at Austin

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