Healthy lifestyle tied to lower long COVID risk

Having a healthy lifestyle, particularly a healthy BMI and adequate sleep, before becoming infected with SARS-CoV-2 helped stave off the development of long COVID, according to a prospective cohort study published in JAMA Internal Medicine.

“In the past decades, scientists have accumulated evidence that healthy lifestyle is good for overall health. However, in the U.S. for example, 70% of the population do not have a healthy body weight and 30% do not sleep enough,” Siwen Wang, MD, a research fellow in the department of nutrition at the Harvard T.H. Chan School of Public Health, said in a press release. “Findings from this study suggest that simple lifestyle changes, such as having adequate sleep, may be beneficial for the prevention of long COVID.”

Previous research has indicated that physical activity may lower the risk for both COVID-19 and severe outcomes from the disease. Additionally, it may help boost the effectiveness of COVID-19 vaccination.

Wang and colleagues conducted a prospective cohort study to better understand associations between lifestyle factors before SARS-CoV-2 infection and the risk for post-COVID-19 condition (PCC) — also known as long COVID — which may affect millions of Americans.

The researchers included data from 32,249 women in the Nurses’ Health Study II cohort who reported their lifestyle habits in 2015 and 2017 and history of COVID-19 from April 2020 to November 2021. The researchers then estimated the relative risk for long COVID in association with the number of healthy lifestyle factors — between zero and six — with Poisson regression, adjusting for comorbidities and demographic factors.

The healthy lifestyle factors included:

• moderate to vigorous physical activity (at least 150 minutes per week);
• high-quality diet (measured as the upper 40% of Alternate Healthy Eating Index–2010 score);
• healthy BMI (18.5 to 24.9 kg/m²);
• adequate sleep (7 to 9 hours per night);
• never smoking; and
• moderate alcohol intake.

Of the nearly 2,000 women who tested positive for COVID-19 during the 19 months of follow up — 97.4% of whom were white and 42.8% of whom were active health care workers — 44% developed long COVID.

Wang and colleagues found that a healthy lifestyle was associated with a reduced risk for long COVID in a dose-dependent manner: women with five to six healthy lifestyle factors had a 49% lower risk for long COVID (RR = 0.51; 95% CI, 0.33-0.78) compared with women who did not have any healthy lifestyle factors.

“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,” Andrea Roberts, PhD, senior research scientist in the department of environmental health at the Harvard T.H. Chan School of Public Health and senior author of the study, said in the release.

Additionally, the researchers noted that sleep (RR= 0.83; 95% CI, 0.72-0.95) and BMI (RR = 0.85; 95% CI, 0.73-1) were both independently associated with long COVID risk.

“While our results suggest that each of the 6 healthy lifestyle factors measured were broadly associated with a lower risk of PCC, in analyses mutually adjusted for all lifestyle factors and comorbidities, BMI and sleep were most strongly associated with lower risk of PCC,” the researchers wrote.

They also reported that, if the associations were, in fact, causal, about 36% of long COVID cases would have been prevented if the participants incorporated five to six healthy lifestyle factors before SARS-CoV-2 infection (population attributable risk percentage, 36%; 95% CI, 14.1-52.7).

The researchers additionally noted that “several biological mechanisms may explain the associations” they observed:

1. each unhealthy lifestyle factor examined has been previously linked to an increased risk for chronic inflammation, which may predispose people to long-term complications in multiple organs after infection;
2. unhealthy lifestyle factors may dysregulate adaptive autoimmunity, which has been found in people with long COVID; and
3. unhealthy lifestyle factors could “predispose to blood clotting abnormalities, another pathophysiological change observed” in those with long COVID.

Wang, Roberts and colleagues concluded that future research should assess whether lifestyle interventions could help mitigate the risk for and symptoms of long COVID.

References:

• Following healthy lifestyle may reduce risk of long COVID. https://www.eurekalert.org/news-releases/978570. Published Feb. 6, 2023. Accessed Feb. 3, 2023.
• Wang S, et al. JAMA Intern Med. 2023;doi:10.1001/jamainternmed.2022.6555.