'Simple steps' to improve sleep could help prevent long COVID

Key takeaways:

• Healthy sleep habits before SARS-CoV-2 infection may reduce the risk for long COVID.
• One researcher told Healio the healthy sleep components that were most strongly associated with lower risk for long COVID.

Having healthy sleep before being infected with SARS-CoV-2 may help protect against long COVID, according to the results of research published in JAMA Network Open.

Long COVID, which encompasses a wide range of symptoms like brain fog and depression, affects 20% to 70% of those who have been infected with SARS-CoV-2, Siwen Wang, MD, a research fellow at the Harvard T.H. Chan School of Public Health’s department of nutrition, and colleagues wrote. Sleep problems are also prevalent, affecting an estimated one in three people worldwide.

Unhealthy sleep dimensions like daytime sleepiness, snoring and sleep apnea, late chronotype or a short or long duration of sleep have been prospectively linked to COVID-19 mortality, susceptibility and severity, the researchers wrote. Additional research has also linked excessive daytime sleepiness, extreme sleep duration and insomnia as causal risk factors for the severity of COVID-19.

“The association between sleep and long COVID is bidirectional,” Wang told Healio.

Hypothesizing that healthier sleep is connected to a lower risk for long COVID, Wang and colleagues conducted a prospective cohort study to assess if multidimensional sleep health before SARS-CoV-2 infection was associated with long COVID risk.

The study included 1,979 participants, all of whom were women, and 97.2% of whom were white, from the Nurses’ Health Study II (2015-2021) who reported testing positive for SARS-CoV-2 infection. Later, 40% developed long COVID.

Sleep health was measured before (from 2015 to 2017) and early into the COVID-19 pandemic (April to August 2020). The researchers defined pre-pandemic sleep scores according to five characteristics: morning chronotype; low insomnia symptoms; no snoring; 7 to 8 hours of sleep per day; and no frequent daytime dysfunction.

Wang and colleagues found that having healthy sleep before being infected with SARS-CoV-2 may help prevent long COVID. For example, those who followed most aspects of healthy sleep before being infected with SARS-COV-2 had about a 30% lower risk for long COVID compared with people who did not have healthy sleep, they found.

The healthy sleep components "most strongly associated with a lower risk for long COVID were having enough sleep every day and good sleep quality," Wang said. “Chronic diseases, such as asthma and heart diseases, or hospitalization due to COVID-19 did not explain these findings.”

Good sleep quality during the pandemic and little to no daytime dysfunction pre-pandemic were independently linked to a lower risk for long COVID, with respective relative risk values of 0.82 (95% CI, 0.69-0.99) and 0.83 (95% CI, 0.71-0.98).

“Our study raises the possibility that simple steps such as setting a regular bedtime; shutting off screens and removing electronic devices before bedtime; avoiding caffeine, large meals, and alcohol late in the day to improve sleep hygiene may reduce risk of long COVID,” Wang said.