Fiona Gispen, MD, MS

HIV Primary Care Physician & Infectious Diseases Researcher

Weill Cornell Medicine | NewYork-Presbyterian

I am a physician specializing in HIV primary care and infectious diseases, and a health services researcher studying how clinical care unfolds in real-world systems.

In clinic, I care for adults longitudinally, focusing on prevention, chronic disease management, and building durable partnerships.

In research, I use large-scale data and causal inference methods to understand treatment patterns, health system gaps, and how to design care that is both clinically effective and practically deliverable.

My work sits at the intersection of infectious diseases, addiction, and health systems.

For Patients For Research Collaborators

Clinical Care

Clinical Practice

I provide HIV primary care and general infectious diseases care for adults at Weill Cornell Medicine.

Who I Care For

Adults living with HIV
Patients seeking preventive sexual health care (PrEP)
Individuals with complex infectious diseases
Patients navigating chronic conditions alongside infection

What You Can Expect

My approach to care is structured but personal.

I focus on:

Evidence-based prevention and treatment
Clear explanations and shared decision-making
Attention to mental health, substance use, and social context
Practical plans that fit real life

Health is shaped by genetics, environment, behavior, access, and stress. My goal is to understand what matters most to you and build a care plan that is realistic, sustainable, and aligned with your priorities.

Care Philosophy

Health is more than the absence of disease. It is a state of balance: biological, psychological, and social.

This includes:

Vaccination and cancer screening
Chronic disease management
Sleep, nutrition, movement
Community and stress regulation

Practice Information

I practice at Weill Cornell Medicine in New York City.

I am not currently accepting new patients, but please contact the office directly through Weill Cornell Medicine to see one of my colleagues.

Research

Research Program

My research examines how health systems deliver care to patients with infectious diseases, particularly at the intersection of infection and substance use, with a focus on understanding treatment completion, care fragmentation, and long-term outcomes using large-scale administrative data.

Core Research Areas

1. Infectious Diseases & Addiction

Drug use-associated infective endocarditis
Serious injection-related infections (SIRIs)
Post-discharge antibiotic treatment patterns

2. Implementation & Health Systems

Care fragmentation following hospitalization
Post-discharge treatment completion
Long-acting antimicrobial strategies
Real-world effectiveness of guideline-based care

3. Causal Inference & Data Science

Target trial emulation
Claims-based cohort studies (Medicaid)
Cost-effectiveness modeling
Decision analysis

Current Focus

My current work uses national Medicaid data to:

Identify drivers of post-hospital care fragmentation
Quantify treatment completion gaps
Model the impact of scalable interventions
Inform policy for populations affected by substance use

Methods

I use:

Longitudinal claims data
Target trial emulation frameworks
Multivariable and causal modeling approaches

Selected Work

Gispen FE, Kapadia SN, et al. Antibiotic Fills and Readmissions After Patient-Directed Discharge in Drug Use-Associated Endocarditis. IDWeek 2025. Oral abstract presented at IDWeek 2025 reporting a national Medicaid analysis of outpatient treatment patterns after high-risk discharges.
Gispen F, Marks K. Update on Vaccination Recommendations for Adults with HIV. Current HIV/AIDS Reports. 2025. Practice-focused review translating evolving preventive care evidence for HIV clinicians.
Gispen F, Luetkemeyer AF, Marks KM. Hepatitis B Virus Vaccination in People with HIV: What's New? Current Opinion in HIV and AIDS. 2025. Updated vaccine strategy synthesis for routine HIV primary care implementation.
Chirunomula S, Muscarella A, Whelchel K, Gispen FE, et al. Hepatitis C cascade of care in a multidisciplinary substance use bridge clinic model in Tennessee. Open Forum Infect Dis. 2024;11(5):ofae205. Evaluation of care delivery pathways for hepatitis C within a multidisciplinary substance use model.

Collaborations

I welcome collaboration in:

Infectious diseases outcomes research
Addiction and infection overlap
Analysis of large administrative datasets

For research inquiries, please use the contact form below.

About

Background

My training includes:

BA & MS - Stanford
MD - Johns Hopkins
Psychiatry Internship - MGH/McLean
Internal Medicine Residency - MGH
Infectious Diseases Fellowship - Weill Cornell

Experience

Assistant Professor of Medicine (Hospitalist), Vanderbilt University Medical Center (2020-2022)
Instructor in Medicine, Division of Infectious Diseases, Weill Cornell Medicine (current)

Outside of Medicine

Outside of work, I play classical piano, swim, practice aerial silks, and am a certified yoga instructor. These pursuits bring joy and community, and remind me that progress is not linear and that no state is permanent.

Contact

For patient, collaboration, or professional inquiries.