Karen C. Johnson, MD, Named Chair of the Department of Preventive Medicine at UTHSC

Karen C. Johnson, MD

Karen C. Johnson, MD, MPH, College of Medicine Endowed Professor in Women’s Health and a principal investigator for several groundbreaking national and international public health research studies, is the new chair of the Department of Preventive Medicine at the University of Tennessee Health Science Center.

A tenured professor in the Departments of Preventive Medicine and Medicine in the UTHSC College of Medicine, Dr. Johnson has brought more than $50 million in National Institutes of Health (NIH) funding as a principal investigator to UTHSC over more than two decades at the university, and more than $45 million in NIH and Department of Defense funding as a co-investigator.

“Karen is a brilliant scientist, whose work is deeply rooted in improving the lives and well-being of people in our communities,” said Scott Strome, Robert Kaplan Executive Dean of the UTHSC College of Medicine. “She is a national and international leader in her field. She is also a tremendous mentor to colleagues and students. I have no doubt that she will expand an already vibrant department, increasing its national stature by addressing medical problems that affect the citizens of our region, our state, and our country.”

Dr. Johnson is the principal investigator for the UTHSC site of the Women’s Health Initiative (WHI), a 40-site clinical trial and cohort study of more than 161,000 women that began in 1993 to look at diseases that affect women and how to help them stay healthier. The study, funded by the National Heart, Lung, and Blood Institute (NHLBI) and expected to continue to 2020, is best known for its recommendation that menopausal hormone therapy should not be started or continued for the purpose of preventing cardiovascular disease. The study found estrogen plus progestin increased the risk of breast cancer, prompting a warning on all estrogen products for postmenopausal women. The use of these products fell 50 percent afterward, and the rates of breast cancer fell worldwide.

Dr. Johnson was the principal investigator at UTHSC for the landmark Systolic Blood Pressure Intervention Trial (SPRINT) funded by the NHLBI to determine the best blood pressure for reducing risk of cardiovascular disease. She was the national vice chair of the steering committee for the study.

In August 2015, the SPRINT trial was stopped early, when the beneficial effects of intensive blood pressure management on mortality and cardiovascular disease were discovered. The findings have spurred worldwide revision of the definition of hypertension and the clinical practice guidelines for treatment.

In January 2019, The SPRINT MIND clinical trial, an offshoot of the SPRINT study, released findings showing that intensive lowering of blood pressure reduced the risk of mild cognitive impairment, a known risk factor for dementia.

As the principal investigator for the Memphis site of the ongoing Look AHEAD (Action for Health in Diabetes) study funded by the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), Dr. Johnson has played a major role in helping to show that long-term, sustained weight loss is possible for people with diabetes.

She is also the principal investigator for the UTHSC site of the TARGIT (Treating Adults at Risk for Weight Gain with Interactive Technology) study aimed at finding ways to help smokers stop smoking without gaining weight by using interactive technology.

Dr. Johnson is the principal investigator for the UTHSC site of the D2d (Vitamin D and Type 2 Diabetes) study funded by the NIDDK to determine if vitamin D can prevent those at risk of diabetes from getting the disease. Earlier this month, the study reported findings that vitamin D supplementation does not reduce likelihood of developing diabetes for those at high risk for the disease, despite observational studies that had indicated otherwise.

Dr. Johnson has been named to the Thomson Reuters list of “The World’s Most Influential Scientific Minds.”

A native Memphian and graduate of Memphis Preparatory School and Lambuth University, Dr. Johnson received her medical degree from the UT College of Medicine and completed an internal medicine residency at the university. A residency in preventive medicine and a master’s degree at Johns Hopkins University in Baltimore cemented her interest in clinical research and prevention.

Dr. Johnson joined the UTHSC faculty in 1990 and served as interim chair for the Department of Preventive Medicine from 2010-2014. She is the co-director of the Tennessee Clinical and Translational Science Institute at UTHSC formed to address health inequities in the Southern United States.