The Biden administration has announced new measures to track down people who defrauded COVID-19 relief programs, researchers have identified three potential post-COVID cognitive trajectories, and more in this week's roundup of COVID-19 news.

• COVID-19 patients who were treated early with the diabetes drug metformin were less likely to develop long COVID, according to results from a new clinical trial. The trial enrolled 1,323 patients, with 1,125 consenting to long-term follow up. To be included in the trial, participants had to be between ages 30 and 85, overweight or obese, have symptoms for less than seven days, and enroll within three days of having a documented infection. In the trial, participants randomly received metformin, ivermectin, fluvoxamine, or a placebo. Overall, 6.3% in the metformin group developed long COVID compared to 10.6% in the placebo group — a 42% reduction in risk. In addition, the researchers noted that the potential benefit may be greater in individuals who took metformin less than four days from symptom onset. On the other hand, neither fluvoxamine nor ivermectin showed any benefit in reducing the risk of long COVID. "Long COVID is a significant public health emergency that may have lasting health, mental health, and economic sequelae, especially in socioeconomically marginalized groups, and metformin is safe, low-cost, and widely available," the researchers wrote. (Hein, MedPage Today, 3/8; Hou, The Hill, 3/8)

• Last week, FDA issued the first emergency use authorization (EUA) for an at-home COVID-19 and flu combination test developed by Lucira Health. Although Lucira CEO Erik Engelson called the authorization a "major milestone," the company has had to file for bankruptcy and cited delays in the test's EUA as one of the reasons. In response to this, FDA on Wednesday released a rare comment to clarify what happened during the EUA process. According to Jeff Shuren, director of FDA's Center for Devices and Radiological Health, the agency ultimately authorized Lucira's test with fewer samples than it would typically require since an NIH program showed that the test would be of appropriate quality even without more samples. Shuren also noted that FDA had initially identified a "toxic substance" in one of the test's components, which was addressed through a redesign. Home test company executives, such as Michael Mina, chief science officer of eMed, have praised FDA's decision to be more flexible with the data it requires for authorization or approval. However, some test manufacturers have also criticized FDA for not being consistent or transparent about the data needed for authorization. "To me, that [decision] makes sense from an industry standpoint. I applaud that," said Nelson Patterson, president and CEO of Anavasi Diagnostics. But, "[d]o I feel cheated? I wish I had known that that would be the standard, because I would have applied last summer." (Trang, STAT, 3/8)

• A new longitudinal study published in Alzheimer's & Dementia has identified three cognitive trajectories for patients who were hospitalized with severe COVID-19. In the study, researchers evaluated COVID-19 patients who were hospitalized between March and December 2020 at the Hospital das Clinicas of the University of Sao Paulo Medical School. The mean age of the participants was 64.9 years, 44% were women, and 63% were white. The participants were assessed at one, three, six, nine, and 12 months to determine their cognitive function. Overall, out of 946 patients, 69% had no cognitive impairment a month after being discharged, 20.3% had short-term impairment that resolved within a few months, and 10.7% had long-term impairment a year later. Cognitive impairment was also associated with older age, less education, and experiencing delirium while hospitalized. According to Tamara Fong, from Harvard Medical School and Beth Israel Deaconess Medical Center, who was not involved in the study, the findings provide researchers with a better understanding of the long-term effects of severe COVID-19. "From early on in the pandemic, it was observed that delirium rates among patients with COVID-19 ranged between 25% and 30%, and up to 65% in ICU patients," Fong said. "Delirium is known to accelerate the rate of cognitive decline and be an independent risk factor for long-term cognitive decline and dementia; furthermore, patients with underlying dementia have a 2- to 5-fold increased risk for developing delirium." (George, MedPage Today, 3/6)

• The Biden administration last week announced new measures to track down and punish individuals who fraudulently used billions of COVID-19 relief funds. According to a report from the Government Accountability Office, the full extent of COVID-19 relief fraud is not yet known, but there were more than $60 billion in fraudulent payments from the Unemployment Insurance program alone. Between March 2020 and January 2022, at least 1,044 people either pleaded guilty or were convicted of defrauding COVID-19 relief programs. Currently, charges are pending for another 609 individuals or entities. President Joe Biden has pledged $1.6 billion to increase law enforcement manpower and implement new programs that will help prevent fraud, prosecute scammers, and assist victims of identity theft. "We want to not only capture them and get their funds, we want to send a signal to them that you can run, but you cannot hide," said Gene Sperling, a senior advisor to the Biden administration who is overseeing the implementation of the COVID-relief plan. (Collins, USA Today, 3/2)

• COVID-19 may be associated with lower brain oxygen and lead to other cognitive impairment, according to a new study published in Brain, Behavior, & Immunity – Health. For the study, researchers combined the results from two parallel studies on how COVID-19 may impact cognitive function. In the first study, researchers compared oxygen saturation in the prefrontal cortex to cognitive function on computer tasks in 120 participants, 52 of whom had a prior COVID-19 infection. Overall, the researchers found that a previous infection most significantly affected executive functioning, and participants in this group had lower oxygen than expect on the right side of the frontal cortex. In the second study, the researchers conducted two waves of surveys between September 2021 and March 2022. Participants in the survey who reported a prior COVID-19 infection also self-reported cognitive issues and psychiatric symptoms. "Our two studies, using very different methods, highlight the need to understand the full range of harms of COVID-19 illness," said Peter Hall, a researcher in the School of Public Health Sciences at the University of Waterloo and the study's lead author. "We still need to know more about how factors like vaccination affect the course of long COVID.We also need to know about how some physical conditions like diabetes, obesity and hypertension might impact these mechanisms and outcomes." (Hou, "Changing America," The Hill, 3/3; University of Waterloo press release, 3/1)