Featured Publications
Effectiveness of Nirmatrelvir-Ritonavir Against the Development of Post-COVID-19 Conditions Among U.S. Veterans : A Target Trial Emulation.
Ioannou G, Berry K, Rajeevan N, Li Y, Mutalik P, Yan L, Bui D, Cunningham F, Hynes D, Rowneki M, Bohnert A, Boyko E, Iwashyna T, Maciejewski M, Osborne T, Viglianti E, Aslan M, Huang G, Bajema K. Effectiveness of Nirmatrelvir-Ritonavir Against the Development of Post-COVID-19 Conditions Among U.S. Veterans : A Target Trial Emulation. Annals Of Internal Medicine 2023, 176: 1486-1497. PMID: 37903369, PMCID: PMC10620954, DOI: 10.7326/m23-1394.Peer-Reviewed Original ResearchConceptsAcute COVID-19Veterans Health AdministrationUntreated comparatorsThromboembolic eventsCOVID-19Severe COVID-19Target trial emulationSARS-CoV-2Post COVID-19 conditionIndex dateVenous thromboembolismBaseline characteristicsCumulative incidencePulmonary embolismAcute infectionMedian ageOral antiviralsTrial emulationVHA careOutpatient treatmentInternational ClassificationHealth AdministrationU.S. veteransVeterans AffairsOrgan systems
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 vaccinesIdentifying Veterans Who Benefit From Nirmatrelvir-Ritonavir: A Target Trial Emulation
Yan L, Bui D, Li Y, Rajeevan N, Rowneki M, Berry K, Argraves S, Huang Y, Hynes D, Cunningham F, Huang G, Aslan M, Ioannou G, Bajema K. Identifying Veterans Who Benefit From Nirmatrelvir-Ritonavir: A Target Trial Emulation. Clinical Infectious Diseases 2024, 79: 643-651. PMID: 38864601, DOI: 10.1093/cid/ciae202.Peer-Reviewed Original ResearchRisk quartileVeterans Health AdministrationLowest risk quartileHighest risk quartileTarget trial emulationRisk prediction modelUntreated veteransRisk of deathOlder veteransYounger veteransHealth AdministrationTrial emulationMeasure incidenceNirmatrelvir-ritonavirVeteransHospitalUntreated participantsCOVID-19QuartileRiskSevere coronavirus disease 2019ParticipantsPersonsCoronavirus disease 2019Severe COVID-19
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 veteransEffectiveness of COVID-19 Treatment With Nirmatrelvir–Ritonavir or Molnupiravir Among U.S. Veterans: Target Trial Emulation Studies With One-Month and Six-Month Outcomes
Bajema K, Berry K, Streja E, Rajeevan N, Li Y, Mutalik P, Yan L, Cunningham F, Hynes D, Rowneki M, Bohnert A, Boyko E, Iwashyna T, Maciejewski M, Osborne T, Viglianti E, Aslan M, Huang G, Ioannou G. Effectiveness of COVID-19 Treatment With Nirmatrelvir–Ritonavir or Molnupiravir Among U.S. Veterans: Target Trial Emulation Studies With One-Month and Six-Month Outcomes. Annals Of Internal Medicine 2023, 176: m22-3565. PMID: 37276589, PMCID: PMC10243488, DOI: 10.7326/m22-3565.Peer-Reviewed Original ResearchConceptsVeterans Health AdministrationCOVID-19 symptom onsetCOVID-19-related outcomesSevere COVID-19Six-month outcomesCOVID-19 vaccinationCOVID-19 treatmentCOVID-19SARS-CoV-2Percent of participantsUntreated control participantsCause mortalitySymptom onsetMedian ageOral antiviralsVHA careOutpatient treatmentHospitalizationHealth AdministrationDay 31U.S. veteransVariant transmissionMost veteransVeterans AffairsOne month