About

Kristen Harris Nwanyanwu, MD, MBA, MHS, is an Associate Professor of Ophthalmology and Visual Science at Yale School of Medicine. She is also the Associate Director of Community Engaged Research and Participant Recruitment at the Yale Center for Clinical Investigation (YCCI). Her educational background includes graduating with highest honors from the University of Michigan, where she earned degrees in African-American Studies and Biochemistry. She obtained her medical degree and MBA from the University of Pennsylvania, and completed her residency in ophthalmology at the University of Michigan, followed by a vitreoretinal surgery fellowship at the Illinois Eye and Ear Infirmary at the University of Illinois at Chicago. She is a board-certified ophthalmologist and practicing vitreoretinal surgeon. Her research focuses on health disparities, access to care, and the surgical management of diabetic retinopathy. She is the principal investigator for the NIH-funded Sight-Saving Engagement and Evaluation in New Haven (SEEN) Program, which aims to identify and address health disparities in diabetic retinopathy through a multi-method approach. Dr. Nwanyanwu has lectured nationally on topics related to health disparities and ophthalmic care. Her work includes developing social needs-based patient navigation in diabetic retinopathy and investigating ocular symptoms in Long COVID, among other projects. She has contributed significantly to research on health equity, federal funding impact on vision research, and disparities in eye health.

Research topics

• Medicine
• Political Science
• Family medicine
• Environmental health
• Nursing
• Gerontology
• Internal medicine
• Medical education
• Optometry
• Demography
• Law

Selected publications

• Interrogating a framework for diabetic retinopathy screening adherence: Qualitative insights from a severely affected and under-adherent population

  PLOS Global Public Health · 2026-04-02

  articleOpen accessSenior author

  To validate and expand upon a framework of diabetic retinopathy (DR) screening adherence by examining barriers and facilitators among individuals with severe DR and those under-adherent to screening. From March 2021 to February 2022, we conducted eight remote semi-structured interviews with adults with diabetes across two participant populations: (1) participants with severe DR who had undergone procedures (n = 4) and (2) participants under-adherent to screening, defined as no eye exam in >1 year (n = 4). We recruited participants from the Yale Eye Center and community referrals. During the interviews, we collected demographic data and presented participants with a DR screening adherence framework previously developed by our group. We transcribed all interviews and conducted analyses using a hybrid deductive-inductive analytic approach informed by grounded theory techniques to identify recurring themes. Themes across both participant populations aligned with the existing framework, including vision status, emotional context, competing concerns, resource availability, cues to action, knowledge-creating experiences, and in-clinic experiences. The patient-doctor relationship emerged as a sub-theme of in-clinic experiences, highlighting the role of trust and communication in supporting sustained eye care engagement. At the individual level, participants with stable vision often perceived no need for screening. At the institutional and structural level, participants identified lack of insurance and transportation as significant barriers. These findings support the robustness of the DR screening adherence framework across varying levels of disease severity and engagement. Interventions that improve patient education, address structural barriers, and strengthen patient-doctor relationships may enhance screening adherence among populations at high risk for vision loss.

  PublisherDOI

• Ocular Symptoms in Long COVID: A Cross-Sectional Study

  Clinical ophthalmology · 2026-03-01 · 2 citations

  articleOpen access

  Introduction: This study compared demographics, socioeconomic characteristics, pre-pandemic health conditions, newly diagnosed health conditions, and long COVID symptoms between participants with and without self-reported new-onset ocular symptoms after COVID-19 infection. Material and Methods: We performed a cross-sectional analysis of the Listen to Immune, Symptom, and Treatment Experiences Now (LISTEN) study. Adults who self-reported long COVID, completed surveys between May 2022 and October 2023, and did not report post-vaccination syndrome were included. Ocular symptoms were defined as self-reported new-onset blurring or loss of vision, dry eyes, or floaters/flashes of light attributed to long COVID. Group comparisons used percentages for categorical variables and median and interquartile range (IQR) for continuous variables as well as Bonferroni-adjusted P-values. A gradient-boosted tree model was used to identify symptoms that differentiated groups. Results: Among 595 participants (median age 46 years [IQR 38-56]; 73% female), 341 (57%) reported ocular symptoms. Pre-pandemic comorbidities were similar between groups. Participants with ocular symptoms had lower EuroQoL visual analogue scale health scores (median 40 [IQR 30-59] vs 51 [IQR 39-70], P < 0.001), greater financial difficulties (20% vs 8.8%, P < 0.001), increased worry about housing stability (16% vs 5.4%, P < 0.001), and higher rates of new-onset dysautonomia (38% vs 15%, P < 0.001) and myalgic encephalomyelitis/chronic fatigue syndrome (21% vs 9.1%, P = 0.005). Key differentiating symptoms included dizziness, cold intolerance, pressure at the base of the head, tinnitus, and tremors. Conclusion: Individuals with long COVID with self-reported new-onset ocular symptoms after infection may represent a more severe phenotype, with poorer health status and greater socioeconomic challenges despite similar pre-pandemic health profiles.

  PublisherOA PDFDOI

• Risk Factors and Consequences of Lapses in Proliferative Diabetic Retinopathy Care in a National Cohort

  Diabetes Care · 2025-09-16 · 2 citations

  article

  OBJECTIVE: To identify prevalence, risk factors, and visual outcomes associated with occurrence and duration of lapses in proliferative diabetic retinopathy (PDR) care. RESEARCH DESIGN AND METHODS: This was a retrospective national cohort study (2008-2023) of adults with PDR and ≥6 months of follow-up who were participating in the Sight Outcomes Research Collaborative. We used multivariable regressions to assess factors associated with lapse occurrence and duration, and compared post-lapse visual acuity by lapse duration. RESULTS: Among 15,211 individuals, 71.8% experienced a lapse in care; 14.2% of the lapses lasted >24 months. Lapses were more common among non-Hispanic Black, younger, and individuals with disability, and less common in those with poor vision or prior PDR treatment. Older age and PDR treatment predicted shorter lapses, and residence in distressed areas predicted longer lapses. Visual acuity worsened after lapses, with greater declines after longer lapses. CONCLUSIONS: Prolonged lapses in PDR care are common, disproportionately affect vulnerable groups, and are associated with persistent vision loss.

  PublisherDOI

• Risk factors and consequences of lapses in proliferative diabetic retinopathy care in a national cohort

  2025-09-16

  articleOpen accessSenior author

  &lt;p dir="ltr"&gt;Objective&lt;/p&gt;&lt;p dir="ltr"&gt;To identify prevalence, risk factors, and visual outcomes associated with occurrence and duration of lapses in proliferative diabetic retinopathy (PDR) care.&lt;/p&gt;&lt;p&gt;&lt;br&gt;&lt;/p&gt;&lt;p dir="ltr"&gt;Research Design and Methods&lt;/p&gt;&lt;p dir="ltr"&gt;Retrospective national cohort study (2008-2023) of adults with PDR and ≥6 months of follow-up in the Sight Outcomes Research Collaborative (SOURCE). We used multivariable regressions to assess factors associated with lapse occurrence and duration, and compared post-lapse visual acuity by lapse duration. &lt;/p&gt;&lt;p&gt;&lt;br&gt;&lt;/p&gt;&lt;p dir="ltr"&gt;Results&lt;/p&gt;&lt;p dir="ltr"&gt;Among 15211 individuals, 71.8% experienced a lapse in care; 14.2% lasted &gt;24 months. Lapses were more common among non-Hispanic Black, younger, and disabled individuals, and less common in those with poor vision or prior PDR treatment. Older age and PDR treatment predicted shorter lapses, and residence in distressed areas predicted longer lapses. Visual acuity worsened following lapses, with greater declines after longer lapses.&lt;/p&gt;&lt;p&gt;&lt;br&gt;&lt;/p&gt;&lt;p dir="ltr"&gt;Conclusions&lt;/p&gt;&lt;p dir="ltr"&gt;Prolonged lapses in PDR care are common, disproportionately affect vulnerable groups, and associated with persistent vision loss.&lt;/p&gt;

  PublisherDOI

• Social Determinants Associated with Diabetic Retinopathy Awareness: National Health and Nutrition Examination Survey (2005-2008)

  American Journal of Ophthalmology · 2025-06-21 · 3 citations

  articleOpen access1st authorCorresponding
  PublisherOA PDFDOI

• Duration and Frequency of Lapses in Care Among Patients with Proliferative Diabetic Retinopathy

  Ophthalmic Epidemiology · 2025-03-25 · 2 citations

  articleOpen accessSenior authorCorresponding
  PublisherOA PDFDOI

• BEnchmarking LLMs for Ophthalmology (BELO) for Ophthalmological Knowledge and Reasoning

  ArXiv.org · 2025-07-21 · 1 citations

  articleOpen access

  Current benchmarks evaluating large language models (LLMs) in ophthalmology are limited in scope and disproportionately prioritise accuracy. We introduce BELO (BEnchmarking LLMs for Ophthalmology), a standardized and comprehensive evaluation benchmark developed through multiple rounds of expert checking by 13 ophthalmologists. BELO assesses ophthalmology-related clinical accuracy and reasoning quality. Using keyword matching and a fine-tuned PubMedBERT model, we curated ophthalmology-specific multiple-choice-questions (MCQs) from diverse medical datasets (BCSC, MedMCQA, MedQA, BioASQ, and PubMedQA). The dataset underwent multiple rounds of expert checking. Duplicate and substandard questions were systematically removed. Ten ophthalmologists refined the explanations of each MCQ's correct answer. This was further adjudicated by three senior ophthalmologists. To illustrate BELO's utility, we evaluated six LLMs (OpenAI o1, o3-mini, GPT-4o, DeepSeek-R1, Llama-3-8B, and Gemini 1.5 Pro) using accuracy, macro-F1, and five text-generation metrics (ROUGE-L, BERTScore, BARTScore, METEOR, and AlignScore). In a further evaluation involving human experts, two ophthalmologists qualitatively reviewed 50 randomly selected outputs for accuracy, comprehensiveness, and completeness. BELO consists of 900 high-quality, expert-reviewed questions aggregated from five sources: BCSC (260), BioASQ (10), MedMCQA (572), MedQA (40), and PubMedQA (18). A public leaderboard has been established to promote transparent evaluation and reporting. Importantly, the BELO dataset will remain a hold-out, evaluation-only benchmark to ensure fair and reproducible comparisons of future models.

  PublisherOA PDF

• Interrogating a framework for diabetic retinopathy screening adherence: qualitative interviews of a severe disease and unengaged population

  medRxiv · 2025-05-31

  preprintOpen accessSenior authorCorresponding

  Abstract Background To interrogate a framework of diabetic retinopathy (DR) screening adherence by conducting qualitative interviews with individuals with severe DR and those unengaged in eye care. Methods From March 2021 to February 2022, we conducted eight remote semi-structured interviews with participants diagnosed with diabetes divided into two cohorts: those with severe DR who had undergone procedures (n=4) and those unengaged in eye care for &gt;1 year (n=4). We recruited participants from an academic faculty practice, community referrals, and word of mouth. During the interviews, we collected demographic data and presented participants with a DR screening utilization framework previously developed by our group. We transcribed all interviews and conducted analyses using grounded theory and the constant comparative method to identify recurring themes. Results In the unengaged cohort, seven recurring themes emerged: vision status , emotional context , competing concerns , resource availability , cues to action , knowledge-creating experiences , and in-clinic experiences . These themes also emerged in the severe disease cohort, with the addition of the patient-doctor relationship . At the individual level, participants with stable vision often perceived no need for screening. At the interpersonal level, participants identified powerful patient-doctor relationships that empowered them to seek care. At the institutional and structural level, participants identified lack of insurance and transportation as significant barriers. Conclusions Improving education about DR, increasing resource accessibility, and strengthening the patient-doctor relationship may mitigate barriers to DR screening in populations at highest-risk for vision loss. To do so, we must implement innovative strategies, such as co-designed educational videos and digital health tools.

  PublisherOA PDFDOI

• Proliferative Diabetic Retinopathy Disproportionately Impacts Distressed Communities Near a Northeastern Academic Center

  Ophthalmology Science · 2025-07-02 · 1 citations

  articleOpen accessSenior author

  <h2>Abstract</h2><h3>Purpose</h3> To identify associations between social determinants of health (SDoH) and progression of proliferative diabetic retinopathy (PDR). <h3>Design</h3> Secondary analysis of a retrospective cohort study. <h3>Participants</h3> We extracted data from electronic medical records of individuals at the Yale Eye Center or Dana Eye Clinic, ages 18 and over, who had a documented diagnosis of non-proliferative diabetic retinopathy (NPDR) at their first recorded (index) ophthalmology visit within the study period. <h3>Methods</h3> We identified participants with NPDR whose disease progressed to PDR during the study time period. We assigned Distressed Communities Index (DCI) scores using participants' zip codes and created a visualized geographic distribution of scores using ArcGIS. We assessed differences in sociodemographic and health characteristics between participants whose disease progressed to PDR and those whose disease did not progress using 2-sample t-tests, Chi-square, and Fisher's exact tests where appropriate. We used logistic regression to assess the associations between SDoH and progression to PDR. We conducted a time-to-event analysis using Cox proportional hazards regression, adjusting for relevant confounders. Main Outcome Measures: The primary outcome was the progression from NPDR to PDR. <h3>Results</h3> Among 1,354 participants, 137 (10%) developed PDR within the study's seven-year period. Of the 137, 54% were male, 46% were age 65 and older, 35% identified as White or Caucasian, and 34% identified as Black or African American. Those whose disease progressed to PDR had significantly worse DCI scores compared to those whose disease did not progress (mean (SD) 64 (26) vs. 58 (27), P=0.015). Unadjusted logistic regression revealed a significant association between DCI and progression to PDR (P = 0.037), while the adjusted model did not (P = 0.124). <h3>Conclusions</h3> Participants with disease progression to PDR were more likely to live in disadvantaged areas. Using socioeconomic data and geographic mapping to identify high-risk populations may help healthcare professionals implement early screening and provide better resources for those at risk of retinal disease progression.

  PublisherOA PDFDOI

• Risk factors and consequences of lapses in proliferative diabetic retinopathy care in a national cohort

  2025-09-16

  articleOpen accessSenior author

  &lt;p dir="ltr"&gt;Objective&lt;/p&gt;&lt;p dir="ltr"&gt;To identify prevalence, risk factors, and visual outcomes associated with occurrence and duration of lapses in proliferative diabetic retinopathy (PDR) care.&lt;/p&gt;&lt;p&gt;&lt;br&gt;&lt;/p&gt;&lt;p dir="ltr"&gt;Research Design and Methods&lt;/p&gt;&lt;p dir="ltr"&gt;Retrospective national cohort study (2008-2023) of adults with PDR and ≥6 months of follow-up in the Sight Outcomes Research Collaborative (SOURCE). We used multivariable regressions to assess factors associated with lapse occurrence and duration, and compared post-lapse visual acuity by lapse duration. &lt;/p&gt;&lt;p&gt;&lt;br&gt;&lt;/p&gt;&lt;p dir="ltr"&gt;Results&lt;/p&gt;&lt;p dir="ltr"&gt;Among 15211 individuals, 71.8% experienced a lapse in care; 14.2% lasted &gt;24 months. Lapses were more common among non-Hispanic Black, younger, and disabled individuals, and less common in those with poor vision or prior PDR treatment. Older age and PDR treatment predicted shorter lapses, and residence in distressed areas predicted longer lapses. Visual acuity worsened following lapses, with greater declines after longer lapses.&lt;/p&gt;&lt;p&gt;&lt;br&gt;&lt;/p&gt;&lt;p dir="ltr"&gt;Conclusions&lt;/p&gt;&lt;p dir="ltr"&gt;Prolonged lapses in PDR care are common, disproportionately affect vulnerable groups, and associated with persistent vision loss.&lt;/p&gt;

  PublisherDOI

Recent grants

• Undiagnosed Diabetic Retinopathy: Using Participatory Science to Design an Intervention for Patients at High-Risk for Blindness

  NIH · $1.3M · 2019–2024

Frequent coauthors

• Joshua D. Stein

  University of Michigan–Ann Arbor

  12 shared

• Evan M. Chen

  University of California, San Francisco

  10 shared

• Joana E. Andoh

  8 shared

• Christopher C. Teng

  Visual Sciences (United States)

  7 shared

• Tahreem A. Mir

  Vanderbilt Health

  6 shared

• Adrienne W. Scott

  Office of Diversity and Inclusion

  6 shared

• Jennifer I. Lim

  University of Illinois Chicago

  6 shared

• Nidhi Talwar

  University of Michigan–Ann Arbor

  6 shared

Labs

• Ophthalmology Interest Group (OIG)PI

Education

• B.A., African-American Studies

  University of Michigan

• B.S., Biochemistry

  University of Michigan