Having a healthy lifestyle before being infected with the SARS-CoV-2 virus may help protect against long COVID, suggest results from the Nurses’ Health Study II cohort.
Many studies have assessed risks associated with serious COVID-19 infection, but it is less clear why some people develop post–COVID-19 condition, also known as “long COVID.”
This condition, defined in this study as having COVID-19 symptoms for at least four weeks after an initial infection with SARS-CoV-2, is estimated to impact 20-40 percent of all people who are infected with SARS-CoV-2. However, the risk is higher in unvaccinated individuals and those requiring hospitalization during their initial infection (50-70 percent).
To investigate this further, Andrea Roberts, a senior researcher at the Harvard T.H. Chan School of Public Health, and colleagues assessed lifestyle and health factors that might be linked to long COVID in 1981 women from the Nurses’ Health Study II cohort. The study describing their findings is published in JAMA Internal Medicine.
Pre-COVID lifestyle and health factors were measured in participants in 2015 and 2017. These were: body mass index (BMI), smoking status, level of physical activity, alcohol intake, diet quality, and average sleep duration. Individuals were assessed to see if they met ‘healthy’ status for each of the six factors. Namely, a BMI of 18.5-24.9, never smoking, completing at least 150 minutes per week of moderate to vigorous physical activity, having moderate alcohol intake (5 to 15 g/d), high diet quality (upper 40% of Alternate Healthy Eating Index–2010 score), and having adequate sleep (7 to 9 h/d).
The researchers included 1981 women with a positive SARS-CoV-2 test in the study who were followed-up for 19 months to assess long-COVID status. The average age was 65 years, most were White and around 43% were still working in health care.
Overall, 871 (44%) developed long COVID. Having a healthy lifestyle prior to infection was linked to lower risks of developing extended symptoms. Women with five to six healthy lifestyle factors had a 49% lower risk of developing long COVID compared with women with no healthy lifestyle factors. Notably, results were comparable if the definition of long COVID was changed to having symptoms for at least two months after initial infection.
Sleep level and BMI were independently linked to long COVID risk, with healthy versus non-healthy status of these two factors reducing risk by 17% and 15%, respectively.
“With ongoing waves of COVID-19, long COVID has created a serious public health burden. Our findings raise the possibility that adopting more healthy behaviors may reduce the risk of developing long COVID,” said Roberts in a press statement.