2024
Development of a prediction model for 30-day COVID-19 hospitalization and death in a national cohort of Veterans Health Administration patients–March 2022—April 2023
Bui D, Bajema K, Huang Y, Yan L, Li Y, Rajeevan N, Berry K, Rowneki M, Argraves S, Hynes D, Huang G, Aslan M, Ioannou G. Development of a prediction model for 30-day COVID-19 hospitalization and death in a national cohort of Veterans Health Administration patients–March 2022—April 2023. PLOS ONE 2024, 19: e0307235. PMID: 39365775, PMCID: PMC11451987, DOI: 10.1371/journal.pone.0307235.Peer-Reviewed Original ResearchConceptsVeterans Health AdministrationCOVID-19 hospitalizationArea under the receiver operating characteristic curveComprehensive electronic health recordNational cohortElectronic health recordsAll-cause mortalityNational cohort of patientsFull modelHealth recordsHealth AdministrationReceipt of COVID-19 vaccineMortality riskEpidemiology of COVID-19COVID-19High-risk patientsBrier scoreCohort of patientsAnti-SARS-CoV-2 treatmentCOVID-19 vaccineReceiver operating characteristic curveCalibration interceptHospitalAntiviral treatmentAvailability of effective vaccinesSelf-Reported Everyday Functioning After COVID-19 Infection
Iwashyna T, Smith V, Seelye S, Bohnert A, Boyko E, Hynes D, Ioannou G, Maciejewski M, O’Hare A, Viglianti E, Berkowitz T, Pura J, Womer J, Kamphuis L, Monahan M, Bowling C, Admon A, Akgun K, Anderson S, Aslan M, Au D, Backus L, Bajema K, Baraff A, Batten L, Berkowitz T, Bernstein T, Berry Wyatt K, Bogdan J, Bosworth H, Boucher N, Burwick N, Cabrales A, Cano J, Chai W, Chen J, Cheung K, Crothers K, Curtis J, Davis M, Del Monico E, Dobalian A, Doll J, Dominitz J, Eastment M, Fan V, Ferguson J, Floyd B, Fox A, Goetz M, Govier D, Green P, Hastings S, Hauschildt K, Hawkins E, Hebert P, Helfand M, Hickok A, Horowitz D, Hough C, Hu E, Ikuta K, Jones B, Jones M, Kamphuis L, Kaufman B, Knight S, Korpak A, Korpela P, Kumbier K, Langa K, Laundry R, Lavin S, Li Y, Linquist J, McCready H, Michel M, Miles A, Milne J, Monahan M, Morelli D, Mutalik P, Naylor J, Neiderhausen M, Newell S, Nugent S, Ong M, Osborne T, Peterson M, Peterson A, Prescott H, Rajeevan N, Reddy A, Rouse M, Rowneki M, Saha S, Saini S, Shah J, Shahoumian T, Shaukat A, Shepherd-Banigan M, Showalter W, Slatore C, Smith N, Smith B, Suri P, Sussman J, Takata Y, Teo A, Thomas E, Thomas L, Tuepker A, Veigulis Z, Vig E, Vranas K, Wang X, Wicks K, Winchell K, Wong E, Woods C, Wysham K, Yan L, Zulman D. Self-Reported Everyday Functioning After COVID-19 Infection. JAMA Network Open 2024, 7: e240869. PMID: 38427352, PMCID: PMC10907923, DOI: 10.1001/jamanetworkopen.2024.0869.Peer-Reviewed Original ResearchConceptsEveryday functioningActivities of daily livingSelf-reported everyday functioningCOVID-19 infectionImpact of COVID-19 infectionDaily livingVeterans AffairsCOVID-19 cohortDocumented COVID-19Instrumental activities of daily livingMatched pairs of participantsHealth-related quality of lifePairs of participantsCohort studyProportion of veteransControl cohortLife-space mobilityStudy of veteransCohort study of veteransUS Veterans AffairsHealth-related qualityDocumented COVID-19 infectionSelf-reportTarget trial emulationQuality of lifeChanges in Outpatient Health Care Use After COVID-19 Infection Among Veterans
Hebert P, Kumbier K, Smith V, Hynes D, Govier D, Wong E, Kaufman B, Shepherd-Banigan M, Rowneki M, Bohnert A, Ioannou G, Boyko E, Iwashyna T, O’Hare A, Bowling C, Viglianti E, Maciejewski M, Admon A, Akgun K, Anderson L, Anderson S, Aslan M, Au D, Backus L, Bajema K, Baraff A, Batten L, Berkowitz T, Bernstein T, Berry Wyatt K, Bogdan J, Borgerding J, Bosworth H, Boucher N, Burwick N, Byrd K, Cabrales A, Cano J, Chai W, Chen J, Cheung K, Crothers K, Cummin G, Curtis J, Davis M, Del Monico E, Dennis P, Dobalian A, Doll J, Dominitz J, Eastment M, Fan V, Ferguson J, Floyd B, Fox A, Goetz M, Green P, Hastings S, Hauschildt K, Hawkins E, Helfand M, Hickok A, Horowitz D, Hough C, Hu E, Ikuta K, Jones B, Jones M, Kamphius L, Knight S, Korpak A, Korpela P, Langa K, Laundry R, Lavin S, Li Y, Lindquist J, McCready H, Meyer C, Michel M, Miles A, Milne J, Monahan M, Morelli D, Mutalik P, Naylor J, Niederhausen M, Newell S, Nugent S, Ong M, Osborne T, Peterson M, Peterson A, Prescott H, Pura J, Rajeevan N, Reddy A, Rouse M, Saha S, Saini S, Seelye S, Shah J, Shahoumian T, Shaukat A, Showalter W, Slatore C, Smith B, Smith N, Streja E, Suri P, Sussman J, Takata Y, Teo A, Thomas E, Thomas L, Tuepker A, Turner A, Veigulis Z, Vig E, Vranas K, Wang X, Wicks K, Winchell K, Womer J, Woods C, Wysham K, Yan L, Zulman D. Changes in Outpatient Health Care Use After COVID-19 Infection Among Veterans. JAMA Network Open 2024, 7: e2355387. PMID: 38334995, PMCID: PMC10858406, DOI: 10.1001/jamanetworkopen.2023.55387.Peer-Reviewed Original ResearchMeSH KeywordsAgedCOVID-19HumansMaleMedicareMiddle AgedOutpatientsRetrospective StudiesTelemedicineUnited StatesVeteransConceptsOutpatient health care useHealth care useCare useOutpatient useOutpatient visitsPrimary care visitsCounts of outpatient visitsPrimary care patientsOutpatient care utilizationCategories of careVeterans Affairs Corporate Data WarehouseCorporate Data WarehouseIncreased outpatient visitsNegative binomial regression modelsBinomial regression modelsCare visitsCare utilizationPopulation surveillance studyRetrospective cohort studyCare patientsUninfected veteransCOVID-19 infectionMain OutcomesPeri-infection periodCohort study
2023
Metformin prescription for U.S. veterans with prediabetes, 2010–2019
Gulanski B, Goulet J, Radhakrishnan K, Ko J, Li Y, Rajeevan N, Lee K, Heberer K, Lynch J, Streja E, Mutalik P, Cheung K, Concato J, Shih M, Lee J, Aslan M. Metformin prescription for U.S. veterans with prediabetes, 2010–2019. Journal Of Investigative Medicine 2023, 72: 139-150. PMID: 37668313, DOI: 10.1177/10815589231201141.Peer-Reviewed Original ResearchConceptsBody mass indexVeterans Health AdministrationIncident prediabetesHigh riskHealth AdministrationRetrospective observational cohort studyType 2 diabetes mellitusUse of metforminObservational cohort studyProportion of veteransMetformin prescribingGestational diabetesCohort studyMetformin prescriptionDiabetes mellitusDiabetes preventionMass indexCardiovascular diseaseMultivariable modelPrediabetesSubset of individualsMetforminU.S. veteransHealthcare systemVeteransAnti–SARS-CoV-2 Pharmacotherapies Among Nonhospitalized US Veterans, January 2022 to January 2023
Yan L, Streja E, Li Y, Rajeevan N, Rowneki M, Berry K, Hynes D, Cunningham F, Huang G, Aslan M, Ioannou G, Bajema K. Anti–SARS-CoV-2 Pharmacotherapies Among Nonhospitalized US Veterans, January 2022 to January 2023. JAMA Network Open 2023, 6: e2331249. PMID: 37651140, PMCID: PMC10472184, DOI: 10.1001/jamanetworkopen.2023.31249.Peer-Reviewed Original ResearchConceptsCOVID-19 pharmacotherapyVeterans Health AdministrationVeterans Integrated Service NetworkSARS-CoV-2Higher Charlson Comorbidity Index scoresCharlson Comorbidity Index scoreNon-Hispanic veteransComorbidity Index scoreProportion of patientsSymptomatic COVID-19Multivariable logistic regressionCOVID-19 vaccinationCohort studyMedicare databaseVHA careUS veteransMAIN OUTCOMEMedical conditionsHispanic veteransPharmacotherapyHealth AdministrationIndex scoreCommunity careNonhospitalized personsWhite veterans
2021
Polygenic Breast Cancer Risk for Women Veterans in the Million Veteran Program
Minnier J, Rajeevan N, Gao L, Park B, Pyarajan S, Spellman P, Haskell SG, Brandt CA, Luoh SW. Polygenic Breast Cancer Risk for Women Veterans in the Million Veteran Program. JCO Precision Oncology 2021, 5: 1178-1191. PMID: 34381935, PMCID: PMC8345920, DOI: 10.1200/po.20.00541.Peer-Reviewed Original ResearchConceptsBreast Cancer Risk Assessment ToolCancer Risk Assessment ToolIncident breast cancerAbsolute lifetime riskAA womenRisk assessment toolIncident casesLifetime riskBreast cancerMillion Veteran ProgramAccurate breast cancer risk assessmentProstate Cancer Cohort ConsortiumBreast cancer risk assessmentPrior BC diagnosisBreast cancer riskClinical risk modelVeteran ProgramRisk prediction modelCancer risk assessmentAssessment toolIncident BCAfrican ancestryHazard ratioProspective cohortMultiracial cohort
2020
Genome-Wide Association Studies of Schizophrenia and Bipolar Disorder in a Diverse Cohort of US Veterans
Bigdeli TB, Fanous AH, Li Y, Rajeevan N, Sayward F, Genovese G, Gupta R, Radhakrishnan K, Malhotra AK, Sun N, Lu Q, Hu Y, Li B, Chen Q, Mane S, Miller P, Cheung KH, Gur RE, Greenwood TA, Braff DL, on the Genetics of Schizophrenia C, Achtyes ED, Buckley PF, Escamilla MA, Lehrer D, Malaspina DP, McCarroll SA, Rapaport MH, Vawter P, Pato MT, Pato CN, Investigators G, Zhao H, Kosten TR, Brophy M, Pyarajan S, Shi Y, O’Leary T, Gleason T, Przygodzki R, Muralidhar S, Gaziano JM, Program M, Huang GD, Concato J, Siever LJ, Aslan M, Harvey PD. Genome-Wide Association Studies of Schizophrenia and Bipolar Disorder in a Diverse Cohort of US Veterans. Schizophrenia Bulletin 2020, 47: 517-529. PMID: 33169155, PMCID: PMC7965063, DOI: 10.1093/schbul/sbaa133.Peer-Reviewed Original Research
2019
Genome‐wide association study of cognitive performance in U.S. veterans with schizophrenia or bipolar disorder
Harvey PD, Sun N, Bigdeli TB, Fanous AH, Aslan M, Malhotra AK, Lu Q, Hu Y, Li B, Chen Q, Mane S, Miller P, Rajeevan N, Sayward F, Cheung K, Li Y, Greenwood TA, Gur RE, Braff DL, on the Genetics of Schizophrenia C, Brophy M, Pyarajan S, O'Leary TJ, Gleason T, Przygodszki R, Muralidhar S, Gaziano JM, Concato J, Zhao H, Siever LJ. Genome‐wide association study of cognitive performance in U.S. veterans with schizophrenia or bipolar disorder. American Journal Of Medical Genetics Part B Neuropsychiatric Genetics 2019, 183: 181-194. PMID: 31872970, DOI: 10.1002/ajmg.b.32775.Peer-Reviewed Original ResearchMeSH KeywordsAdultAgedAllelesBipolar DisorderCognitionCognition DisordersFemaleGenome-Wide Association StudyGenotypeHumansMaleMiddle AgedNeuropsychological TestsOligonucleotide Array Sequence AnalysisPolymorphism, Single NucleotideSchizophreniaUnited StatesUnited States Department of Veterans AffairsVeteransGenome-wide Association Study of Maximum Habitual Alcohol Intake in >140,000 U.S. European and African American Veterans Yields Novel Risk Loci
Gelernter J, Sun N, Polimanti R, Pietrzak RH, Levey DF, Lu Q, Hu Y, Li B, Radhakrishnan K, Aslan M, Cheung KH, Li Y, Rajeevan N, Sayward F, Harrington K, Chen Q, Cho K, Honerlaw J, Pyarajan S, Lencz T, Quaden R, Shi Y, Hunter-Zinck H, Gaziano JM, Kranzler HR, Concato J, Zhao H, Stein MB, Program D, Program M. Genome-wide Association Study of Maximum Habitual Alcohol Intake in >140,000 U.S. European and African American Veterans Yields Novel Risk Loci. Biological Psychiatry 2019, 86: 365-376. PMID: 31151762, PMCID: PMC6919570, DOI: 10.1016/j.biopsych.2019.03.984.Peer-Reviewed Original ResearchConceptsAdditional genome-wide significant lociRisk lociWide association study (GWAS) analysisAssociation studiesGenome-wide significant lociGenome-wide association studiesGenetic correlationsWide association studyNovel risk lociAlcohol-related traitsStrong statistical supportSmoking-related traitsAdditional genomesSignificant lociPancreatic delta cellsChromosome 4Chromosome 11Protein productsChromosome 8Quantitative phenotypesMillion Veteran ProgramVeterans Affairs Million Veteran ProgramLociCell typesChromosome 17
2018
Suicidal ideation and behavior in US veterans with schizophrenia or bipolar disorder
Harvey PD, Posner K, Rajeevan N, Yershova KV, Aslan M, Concato J. Suicidal ideation and behavior in US veterans with schizophrenia or bipolar disorder. Journal Of Psychiatric Research 2018, 102: 216-222. PMID: 29698922, DOI: 10.1016/j.jpsychires.2018.04.014.Peer-Reviewed Original ResearchConceptsSevere mental illnessSuicidal ideationPsychiatric comorbidityUS veteransHigh riskVeteran populationGreater clinical focusPopulation of patientsVeterans Affairs studyMultiple psychiatric comorbiditiesStudy of veteransLifetime suicidal ideationHigh suicide riskDemographic factorsBetter risk predictionMajority of veteransClinical factorsFunctional statusLifetime riskRisk factorsMajor depressionMultinomial logistic regressionLower riskSCZ patientsClinical attributes
2000
Test-retest reproducibility of extrastriatal dopamine D2 receptor imaging with [123I]epidepride SPECT in humans.
Varrone A, Fujita M, Verhoeff NP, Zoghbi SS, Baldwin RM, Rajeevan N, Charney DS, Seibyl JP, Innis RB. Test-retest reproducibility of extrastriatal dopamine D2 receptor imaging with [123I]epidepride SPECT in humans. Journal Of Nuclear Medicine 2000, 41: 1343-51. PMID: 10945525.Peer-Reviewed Original ResearchConceptsTest-retest variabilityTemporal cortexTest-retest reproducibilityOutcome measuresExtrastriatal regionsD2 receptorsPlasma clearanceExtrastriatal dopamine D2 receptorsGood test-retest variabilityConstant infusion paradigmExtrastriatal D2 receptorsDopamine D2 receptorsBrain radioactivityStriatal radioactivityHealthy volunteersReceptor densityInfusion rateParent tracerSPECT studiesLess test-retest variabilityCortexHigh test-retest variabilityFree fractionReceptor quantificationReceptors
1999
[123I]Iomazenil SPECT benzodiazepine receptor imaging in schizophrenia
Verhoeff N, Soares J, D’Souza C, Gil R, Degen K, Abi-Dargham A, Zoghbi S, Fujita M, Rajeevan N, Seibyl J, Krystal J, van Dyck C, Charney D, Innis R. [123I]Iomazenil SPECT benzodiazepine receptor imaging in schizophrenia. Psychiatry Research 1999, 91: 163-173. PMID: 10641580, DOI: 10.1016/s0925-4927(99)00027-x.Peer-Reviewed Original ResearchConceptsDuration of illnessHealthy control subjectsControl subjectsGamma-aminobutyric acidLeft precentral gyrusSuperior occipital gyrusPANSS scoresPrecentral gyrusOccipital gyrusSignificant differencesTotal brain uptakeNon-smoking patientsGray matter atrophyConstant infusion paradigmPathophysiology of schizophreniaCortical brain regionsSingle photon emissionTypical antipsychoticsAtypical antipsychoticsCigarette smokingInhibitory neurotransmissionBrain uptakeInfusion paradigmMatter atrophyPostmortem studiesEffects of Vigabatrin on the GABAergic System as Determined by [123I]Iomazenil SPECT and GABA MRS
Verhoeff N, Petroff O, Hyder F, Zoghbi S, Fujita M, Rajeevan N, Rothman D, Seibyl J, Mattson R, Innis R. Effects of Vigabatrin on the GABAergic System as Determined by [123I]Iomazenil SPECT and GABA MRS. Epilepsia 1999, 40: 1433-1438. PMID: 10528940, DOI: 10.1111/j.1528-1157.1999.tb02016.x.Peer-Reviewed Original ResearchConceptsEffects of vigabatrinGABA levelsTissue GABA levelsMR imagingCentral gamma-aminobutyric acidGABA magnetic resonance spectroscopyDistribution volumeHealthy age-matched controlsOccipital GABA levelsAge-matched controlsGamma-aminobutyric acidVolume of interestSingle photon emissionMagnetic resonance spectroscopyTotal plasma activityT1-weighted MR imagingPartial seizuresGABAergic systemOccipital cortexConstant infusion methodPlasma activityVigabatrinOccipital activityEffective doseWilcoxon testChanges of benzodiazepine receptors during chronic benzodiazepine administration in humans
Fujita M, Woods S, Verhoeff N, Abi-Dargham A, Baldwin R, Zoghbi S, Soares J, Jatlow P, Krystal J, Rajeevan N, Charney D, Seibyl J, Innis R. Changes of benzodiazepine receptors during chronic benzodiazepine administration in humans. European Journal Of Pharmacology 1999, 368: 161-172. PMID: 10193652, DOI: 10.1016/s0014-2999(99)00013-8.Peer-Reviewed Original ResearchConceptsClinical effectsReceptor levelsReceptor densityReceptor occupancyChronic benzodiazepine administrationBenzodiazepine receptor densityHealthy human subjectsComparison of baselineSingle photon emissionHopkins Verbal Learning TestInduced sedationVerbal Learning TestBenzodiazepine administrationOral administrationBaseline valuesBenzodiazepine receptorsTolerance developmentDay 3Day 17Day 4Day 10Central typeLearning TestReceptorsHuman subjects
1998
Significance of nonuniform attenuation correction in quantitative brain SPECT imaging.
Rajeevan N, Zubal IG, Ramsby SQ, Zoghbi SS, Seibyl J, Innis RB. Significance of nonuniform attenuation correction in quantitative brain SPECT imaging. Journal Of Nuclear Medicine 1998, 39: 1719-26. PMID: 9776276.Peer-Reviewed Original ResearchConceptsHealthy control subjectsHealthy human control subjectsHuman control subjectsControl subjectsDisease patientsGroup of patientsParkinson's disease patientsNonuniform attenuation correctionOutcome measuresParkinson's diseaseSPECT scansBrain SPECTBrain regionsDopamine transporterPatientsBackground activity ratioNonuniform attenuation mapGold standardModerate improvementScansBrain ROIsSPECT imagesAttenuation correctionDiseaseQuantitative brain SPECT