The following is a summary of some recent studies on COVID-19. They include research that warrants further study to corroborate the findings and that has yet to be certified by peer review.

High-pressure oxygen treatment may help long COVID

Patients with long COVID may see some improvement after breathing pure oxygen in a high-air-pressure environment, according to data from a small Israeli trial.

Researchers randomly assigned 73 patients with post-COVID symptoms lasting at least three months to receive hyperbaric oxygen therapy (HBOT) or a sham treatment.

Patients in the HBOT group spent 40 sessions breathing pure oxygen in a chamber in which the air pressure was two-to-three times higher than normal, allowing the lungs to receive more oxygen than they normally would.

Shortly after the last treatment, the HBOT group showed “significant improvement” compared to the sham group in thinking skills, energy, sleep, psychiatric symptoms, and pain, according to a report published on Tuesday in Scientific Reports.

Symptomatic improvement was associated with magnetic resonance imaging evidence of structural and functional brain healing and improved delivery of oxygen-carrying blood to the brain, the researchers said.

HBOT is often used to treat wounds that are not healing well and has recently been tested as a treatment for traumatic brain injury, but this is the first randomized trial to test it for long COVID. Larger studies are needed to confirm the findings and to identify patients who might benefit, the researchers said.

COVID-19 vaccines linked with longer periods for some women

COVID-19 vaccination may be associated with short-term lengthening of the menstrual cycle for some women, according to a new study.

The findings are drawn from 3,858 female nurses in the United States and Canada who have been filling out questionnaires about their periods twice a year since 2011.

As of December 2021, 91% of them had been vaccinated against the coronavirus.

Before the pandemic, 15% reported irregular cycles; that rose to 22.7% in 2021, the researchers reported on Wednesday in the American Journal of Obstetrics & Gynecology.

Vaccinated women had a 54% higher risk of increased cycle length compared to unvaccinated women, regardless of vaccine type and even after taking pandemic stress and health-related factors into account, the report said.

On closer analysis, vaccination was only associated with change to longer cycles in the first six months after vaccination and among women whose cycles were short, long or irregular before vaccination, not among women with normal length, regular cycles. — Reuters