Research showing value of exercise before a COVID-19 diagnosis earns special recognition

Being active can lower your risk of getting seriously ill with COVID, regardless of your race or the chronic conditions you may have, according to research published last year in the American Journal of Preventive Medicine.

The Kaiser Permanente Southern California findings were important, impactful, and influential. As a result, the journal editors chose the research article, “Associations of Physical Inactivity and COVID-19 Outcomes Among Subgroups,” as the American Journal of Preventive Medicine 2023 Article of the Year.

“Please accept our congratulations on your achievement and …  formal acknowledgment of your substantial contribution to AJPM and excellence in advancing preventive medicine through written scholarship,” the journal editors wrote to Deborah Rohm Young, the article’s lead author.

Dr. Young is the director of the Kaiser Permanente Southern California Department of Research & Evaluation’s Behavioral Research Division. She focuses much of her research on “the study of physical activity, both the effects of physical activity on health outcomes, and also interventions to encourage more people to be physically active.”

“When the pandemic was at its worst, this study showed that exercise made a difference in people’s health outcomes from COVID-19,” she said. “Even those people most at risk of severe outcomes— people with chronic health conditions, people who live in poorer neighborhoods and people of color—all of these groups did better if they were doing at least a little regular exercise before they got COVID.”

Patients report their exercise

She explained that the foundation of the study started 15  years ago when the paper’s senior author, Robert Sallis, MD, encouraged the region’s leadership to assess physical activity at medical appointments, just as they do blood pressure, weight, and temperature.

Dr. Sallis, a family and sports medicine physician at the Kaiser Permanente Fontana Medical Center said he had seen in his practice “how patients who do regular exercise are so much healthier and need less medication. They’re less likely to become depressed and develop heart disease.”

“A passion of mine has been trying to connect fitness with health care. And as part of that, I conceived of an idea to assess exercise in all our patients,” he said. “Exercise as a Vital Sign was adopted within Kaiser Permanente Southern California in 2009 and now every patient is asked about their level of physical activity at their regular appointments.”

When the pandemic hit, Dr. Sallis said he began to suspect the chances for doing well after contracting COVID-19 would be better for people who exercised regularly.

He and Dr. Young partnered to find out if that was true.  Their first study, published in 2021, showed that patients who were consistently inactive had greater odds of hospitalization, admission to intensive care, and death from COVID-19 than patients who were consistently active by meeting the US Physical Activity Guidelines recommendation of at least 150 minutes per week of moderate or greater exercise.

“In this study, we wanted to take that research another step forward,” Dr. Young said. “When we started this research, scientists hadn’t yet determined whether physical activity is associated with less severe outcomes for those people who have chronic conditions. They also hadn’t delved into whether age or sociodemographic inequities made a difference.”

The study was conducted by looking at electronic health records at Kaiser Permanente Southern California. Between January 2020 and May 2021, 480,000 Kaiser Permanente patients in Southern California had a positive COVID-19 test. After excluding patients who didn’t have at least 3 assessments of physical activity in their electronic health records in the prior 2 years and for other reasons such as not getting tested at a Kaiser Permanente facility or not being a member for very long, researchers included 194,000 patients in the study.

Patients categorized by activity level

The researchers categorized patients based on their Exercise Vital Sign into 5 levels of activity from always inactive, which was less than 10 minutes of physical activity per week, to always active which was 150 minutes or more of physical activity a week.

They found:

  • Physical activity was associated with protection against poor COVID-19 outcomes across a variety of demographic and medical characteristics.
  • Pre-existing chronic conditions, such as obesity, cardiovascular disease, diabetes, and hypertension, were strongly associated with COVID-19‒related deaths, however the study showed that if a person with either hypertension or cardiovascular disease is infected, the odds of hospitalization, inpatient deterioration, and death were lower among those who were engaged in some physical activity before the COVID-19 diagnosis, compared with those in the always-inactive category.
  • The amount of physical inactivity among patients with COVID-19 with the highest risk for severe outcomes were those with common chronic diseases, older people, and people of Asian or Pacific Islander, Black, and Hispanic race and ethnicity.
  • Higher odds of poor COVID-19 outcomes among physically inactive patients were seen in all racial and ethnic categories, in most age categories, in all BMI categories, and for patients with and without a diagnosis of cardiovascular disease or hypertension.

“In my mind, exercise is a medicine that I need to prescribe to all my patients,” Dr. Sallis said. “I need to ask them if they’re taking it at every visit. And if they have a chronic disease or they’re at risk for chronic disease, they need to know that exercise helps.”

Dr. Young and Dr. Sallis said they were grateful for the recognition the work has received, and were especially thankful to the team of “outstanding colleagues” who made it possible, including the co-authors on the research: James F. Sallis, PhD, of the University of California San Diego; Aileen Baecker, PhD, Deborah A. Cohen MD, MPH, and Claudia L. Nau, PhD, of the Department of Research & Evaluation; Gary N. Smith, PhD, of Economics Department, Pomona College, Claremont.