The Definition of Clinician-Scientist

An Interview with Charlotte Enns Joslin (OD’97, PhD)
Dr. Charlotte Enns Joslin
Dr. Charlotte Enns Joslin

Those of us serving patients on the front lines of eye care are uniquely positioned to identify clinical questions that can only be answered through research. It is the rare clinician who has the means and the skill set to propose a research question and can set out to find the answer. Meet Buckeye graduate Charlotte Enns Joslin (OD’97, PhD).

Question How did you find your way to The Ohio State University College of Optometry?

I grew up in the northern suburbs of Chicago, and The Ohio State University College of Optometry was my top choice! On paper, I was very impressed with its reputation, and in person, I was even more impressed with its physical and academic presence within the larger medical and health sciences campus.  Prior to attending Ohio State, I was totally naïve with zero connections to Ohio State; after matriculating, I quickly became a fully engaged Buckeye! And I continue to be so, despite my husband (MD) and brother-in-law (PhD) both being Michigan grads – hah!

Question You are Director of the Contact Lens Service, Professor of Ophthalmology, Department of Ophthalmology and Visual Sciences, College of Medicine and Departmental Affiliate, Epidemiology & Biostatistics, School of Public Health at the University of Illinois

As a student at Ohio State, my interests were in medically-necessary contact lenses. I also had the opportunity while at Ohio State to work on the Collaborative Longitudinal Evaluation of Keratoconus (CLEK) Study, which exposed me to clinical research. Subsequently, I completed residency training at Chicago’s Jesse Brown and Hines Veteran Affairs Medical Centers; together, these experiences led me to practicing at an academic medical center, which I have loved due to the complicated patients, the collaborations, and the opportunities. After a couple years of practicing and refining my clinical skills, and continuing efforts as an investigator with the CLEK Study, I realized how much clinical research piqued my curious nature and that my tendency toward an introverted personality was better suited to a balance between clinical practice and research. I recognized I needed more research training, and pursued a National Institutes of Health/National Eye Institute (NIH/NEI) K23 Mentored Career Development Award. With this award, I completed my PhD in epidemiology at UIC and embarked on the road of a clinician-scientist. I haven’t looked back!

Dr. Charlotte Joslin
Charlotte Joslin, OD, PhD reviewing SOL Ojos LOCS II lens grading protocol images (photo by Lauren Kalinowski).
Question Do you consider yourself primarily a clinician, a researcher, or a teacher?

For me, the balance between patient care and research is most rewarding. My patients almost exclusively require medically necessary contact lenses. Probably 70% of them have a diagnosis of keratoconus (the rest have corneal irregularity, limbal stem cell deficiency, neurotrophic, severe dry eyes, etc.), which means I have enjoyed longstanding relationships with most of them, as they have significant chronic disease. In contrast, I especially enjoy the intellectual challenges associated with research:  the discipline, curiosity, adrenaline, and extreme persistence required to succeed. The balance weekly between the two keeps work rewarding. Moreover, as a clinician-scientist I feel I can more readily bring real-life issues back-and-forth between clinic and research, to make a meaningful difference beyond treating the patient directly in front of me.

As I become more established, I have enjoyed becoming more involved with mentoring. For example, under my tenure as Director of UIC’s Contact Lens Service, we established a fellowship in medically-necessary contact lenses, with our eighth trainee beginning this summer.  I also have mentored multiple individuals in research, especially with our current project, Study of Latinos SOL Ojos.

Question I know just enough Spanish to recognize “ojos” means “eyes.” Tell us about the study and how it came to be.

It is a multi-center NIH-NEI funded ancillary study to the Hispanic Community Health Study/Study of Latinos (HCHS/SOL) in Chicago and Miami. HCHS/SOL is a national resource of extensive, high-quality data, and is the largest ever, population-based, longitudinal, multicenter cohort study of Hispanic/Latino adults of diverse backgrounds, including those of Mexican, Cuban, Dominican, Puerto Rican, Central and South American, and other origins.

HSHC/SOL recruited 16,415 participants and has more than 900 accepted manuscript proposals, of which nearly 500 are published. Put simply, HCHS/SOL is the “Framingham Study” of Hispanic/Latinos, and one of the largest NIH/NHLBI-funded longitudinal cohort studies.

After formal proposal of an ancillary study to HCHS/SOL, SOL Ojos received approval, with NIH/NEI funding beginning in September 2019 and participant recruitment to start in March 2020. Needless to say, COVID-19 delayed recruitment; hence, we decided to accelerate the recruitment period to two years as opposed to the planned three years. I am proud that we completed our two-year recruitment on June 30, 2023 and delighted to say we over-recruited by nearly 10%!

Question I know recruitment for studies can be a major challenge. Congratulations on your success!

Thank you. SOL Ojos has a strong emphasis on health disparities/health equity, with the Primary Aims to assess the prevalence of chronic eye disease and the leading causes of blindness (e.g., diabetic retinopathy, glaucoma, macular degeneration, cataracts, visual impairment/blindness) across diverse backgrounds, as well as the novel associations between systemic disease including biomarkers and chronic eye disease.

Question I recall that you were one of the key players to help us “crack the code” to what was happening during the Acanthamoeba Keratitis crisis in 2007. Please tell us your perspective on what happened.

On a national level, the Environmental Protection Agency updated regulations shortly before the increase in Acanthamoeba keratitis cases to reduce the allowable amount of disinfection byproducts in the drinking water supply, as they might be carcinogenic at high levels. Disinfection byproducts form when disinfectants, like chlorine, are added to the water supply to kill microbial pathogens and react with organic materials in the water. Surface waters such as rivers, lakes, and streams are more likely to have organic materials, and disinfection byproducts are of greater concern for systems that use surface water, including Lake Michigan. Methods to reduce disinfection byproducts include adjusting the type and amount of disinfectant used. If any contact lens solution is “permissive” of the survival of an Acanthamoeba organism, then an increase in the overall load of an organism would result in an increase in the absolute number of cases, with the most “permissive” solution resulting in the greatest number of cases.  

Question Did living in Chicago make you ideally suited in some way to be a player in the Acanthamoeba Keratitis study?

Acanthamoeba keratitis is an incredibly rare eye infection. Statistically, most optometrists who provide care to the general population are unlikely to ever see a single case in their entire career. At UIC, as a tertiary care academic institution, we had a strong local corneal referral pattern due in part to the fact that UIC had the second installation of a commercial confocal microscope unit in the entire US, meaning UIC captured nearly all local cases. If the exact same scenario, including the referral pattern, occurred in a smaller metropolitan area, the sample size and study power to detect a statistically significant increase in disease would have been inadequate and the results non-significant. A strength of our study was the fact that this occurred in Chicago, with a unique referral pattern, a large enough population to study, and relative homogeneity in how the Lake Michigan water supply was treated. 

Question What an incredible career you have had and continue to enjoy! Anything else you’d like to share?

As I look back, my career path started at Ohio State with numerous individuals that provided important guidance, and two incredible mentors, Joe Barr (OD’77, MS’79) and Karla Zadnik, OD, PhD. Additionally, I am proud to serve as a mentor to future generations, including recent Buckeye graduate Mary “Araba” Otoo (MPH, OD’22). To the currently enrolled student body, this is your opportunity to seek mentors and collegial relationships that can offer guidance and sage wisdom throughout your career. I am incredibly proud of, and fortunate for, all my experiences with the entire Ohio State Optometry community and look back fondly on my years at Ohio State. Go Buckeyes!