A population-based study analysing over one million individuals suggests that babies born via caesarean section delivery may face a higher risk of developing Crohn’s disease later in life. The findings, published in Acta Obstetricia et Gynecologica Scandinavica, add to a growing body of evidence on long-term impacts of caesarean section delivery.
More and more people are being delivered by caesarean section, and there is interest in understanding possible long-term health consequences of this mode of delivery. One possible route is through a lack of the early exposure of the infant to colonising bacteria via a vaginal delivery. Previous studies suggest that infants delivered by CS are at increased risks of disorders involving the immune system, such as asthma and allergies, type 1 diabetes, celiac disease, obesity, immune deficiencies, and leukaemia and other malignancies affecting young people.
In this study, all full-term individuals registered in the Medical Birth Register in Sweden between 1990 and 2000 were followed until 2017. Among 1 102 468 individuals, of whom 11.6% were delivered by caesarean section and 88.4% were vaginally delivered, caesarean section was associated with a 14% higher risk of developing Crohn’s disease after adjusting for confounding factors. No associations between delivery mode and appendicitis, ulcerative colitis, cholecystitis, or diverticulosis were found.
“Our study is the largest in this field, showing new interesting associations between caesarean section and increased risk later in life for Crohn’s disease. We hypothesise that the underlying mechanism could be the gut microbiome, but further studies will have to confirm this,” said senior author Anna Löf Granström, of the Karolinska Institute.
Adults with low blood levels of urate, the end-product of the purine metabolism in humans, may be at higher risk of sarcopenia and may face a higher risk of early death, according to a new study published in Arthritis & Rheumatology.
Whether or nor low serum urate (SU) levels contribute to adverse outcomes has been the subject of controversy. The study involved 13 979 participants aged 20 years and older, sourced from the National Health and Nutrition Examination Survey from 1999–2006.
Low serum urate concentrations (<2.5 mg/dL in women; <3.5 mg/dL in men) were associated with low lean mass, underweight BMI (<18.5 kg/m2), and higher rates of weight loss. While low SU was associated with increased mortality (61%) before adjusting for body composition, its effect was reduced and non-significant after adjustment for body composition and weight loss.
“These observations support what many have intuited, namely that people with low serum urate levels have higher mortality and worse outcomes not because low urate is bad for health, but rather that low urate levels tend to occur among sicker people, who have lost weight and have adverse body composition,” explained lead author Joshua F. Baker, MD, MSCE, of the University of Pennsylvania. “While this observational study doesn’t disprove a causal association, it does suggest that great care is needed in interpreting epidemiologic associations between urate levels and health outcomes.”
In a study published in the New England Journal of Medicine, researchers have found that metformin, a commonly prescribed diabetes medication, lowers the odds of emergency department visits, hospitalisations, or death due to COVID by over 40%; and over 50% if prescribed early in onset of symptoms. The study also found no positive effect from treatment with either ivermectin or low-dose fluvoxamine.
“Our trial suggests that metformin may reduce the likelihood of needing to go to the emergency room or be hospitalised for COVID,” said Carolyn Bramante, MD, principal investigator of the study.
The primary outcome was in fact low oxygen on a home oxygen monitor, which none of the medications in the trial prevented.
The COVID-OUT trial studied whether metformin, low-doses of the antidepressant fluvoxamine, the controversial antiparasitic ivermectin, or their combinations could serve as possible treatments to prevent ER visits or hospitalisation, as well as Long COVID.
Patients were randomised to receive one of the three drugs individually: placebo, or a combination of metformin and fluvoxamine or metformin and ivermectin. Although the study was placebo-controlled with exact-matching placebo pills, Dr Bramante said that 83% of volunteers received medications supported by existing data because of the six-arm design. Each participant received 2 types of pills to keep their treatment assignment masked, for 3 to 14 days of treatment. Each volunteer tracked their symptoms, and after 14 days, they completed a survey.
The 1323 participants in the trial were limited to adults with a body mass index greater than or equal to 25 kg/m2, which qualifies as overweight. To qualify for the study, volunteers enrolled within three days after receiving a positive COVID test. It was among the first randomised clinical trials for COVID to include pregnant women.
The study included those who were vaccinated and those who were not. This is the first published trial where the majority of participants were vaccinated.
“Although we know COVID vaccines are highly effective, we know that some new strains of the virus may evade immunity and vaccines may not be available worldwide. So we felt we should study safe, available and inexpensive outpatient treatment options as soon as possible,” said Dr Bramante. “Understanding whether outpatient treatments could ensure more people survive the illness if they contract it and have fewer long-term symptoms is an important piece of the pandemic response.”
The clinical trial launched in January 2021 after researchers noticed that outpatient metformin use appeared to decrease the likelihood of mortality from, or being hospitalised for COVID. Their research was published in the Journal of Medical Virology and in The Lancet Healthy Longevity. Test-tube studies also found that metformin inhibited the -CoV-2 in lab settings. These findings, along with additional prospective studies supporting the use of higher-dose fluvoxamine and ivermectin, provided the evidence to include all three medications as well as combination arms.
The majority of people who were likely infected with the Omicron variant were unaware they had the virus, according to a new study published in JAMA Network Open.
“More than one in every two people who were infected with Omicron didn’t know they had it,” said Susan Cheng, MD, MPH, corresponding author of the study. “Awareness will be key for allowing us to move beyond this pandemic.”
Previous work estimated that between 25% and 80% of people infected with SARS-CoV-2 may be asymptomatic. Compared to other variants, Omicron is associated with generally less severe symptoms that may include fatigue, cough, headache, sore throat or a runny nose.
“Our study findings add to evidence that undiagnosed infections can increase transmission of the virus,” said Sandy Y. Joung, MHDS, an investigator at Cedars-Sinai and first author of the study. “A low level of infection awareness has likely contributed to the fast spread of Omicron.”
As part of research into the effects of COVID and the impact of vaccines, the investigators began collecting blood samples from healthcare workers more than two years ago. In the second half of 2021, just before the start of the Omicron variant surge, the investigators were able to expand enrolment to include patients. Of the healthcare workers and patients who have participated in the research, investigators identified 2479 people who had contributed blood samples just prior to or after the start of the Omicron surge. The investigators identified 210 people who likely were infected with the Omicron variant based on newly positive levels of SARS-CoV-2 antibodies.
Study participants were invited to provide health status updates through surveys and interviews. Only 44% of study participants testing positive were aware of their infection. Of the 56% of study participants who were unaware, only 10% reported having any recent symptoms that they attributed to a common cold or other type of infection.
More studies involving larger numbers of people from diverse ethnicities and communities are needed to learn what specific factors are associated with a lack of infection awareness, according to the investigators.
Cheng and colleagues are also studying patterns and predictors of reinfections and their potential to offer long-lasting immunity to SARS-CoV-2. In addition to raising awareness, this information could help people manage their individual risk.
Maintaining excellent cardiovascular health may lower the risk for abnormalities in the small vessels of the brain, a new study suggests.
Scientists aren’t sure what causes the condition, known as cerebral small vessel disease, or CSVD. Previous research shows CSVD contributes to about half of dementia cases, a quarter of clot-caused strokes and most bleeding strokes.
For the new study, researchers looked at data from 3067 older adults in Lishui, China. The study team ranked each person’s cardiovascular health as “poor,” “intermediate” or “ideal” based on three medical factors (blood pressure, cholesterol and blood sugar) and four modifiable behaviours (not smoking, maintaining a healthy weight, eating healthy and being physically active).
Next, they compared cardiovascular health to brain MRI scans that looked for signs of CSVD, such as cerebral microbleeds – remnants of blood that has leaked out of small vessels – and lesions called white matter hyperintensities.
The study found participants with ideal cardiovascular health had 26% lower odds of having CSVD than those with poor cardiovascular health. The research was published Wednesday in the journal Stroke.
“The findings were somewhat expected, since a healthy lifestyle can benefit both the arteries and the brain,” said study co-author Yuesong Pan, a researcher of neurological diseases at Capital Medical University’s Beijing Tiantan Hospital in China.
“This suggests that in clinical practice, the target is to attain an ideal (cardiovascular health) score, not just an intermediate score,” he said. “Patients can use a simple self-measuring scale to adjust their lifestyle, assess the risk of CSVD and reduce their CSVD burden.”
Researchers used the American Heart Association’s tool for scoring cardiovascular health that was recently updated to add sleep duration as an eighth factor for ideal heart and brain health. Pan suggested people use the tool, now known as Life’s Essential 8, to find out their risk for cardiovascular disease.
Dr. José Rafael Romero, a neurologist who wasn’t involved in the research, said CSVD is important because “it does not have a specific treatment and it is such a strong contributor to stroke and dementia, which are epidemic conditions around the world.”
In 2020, 7.1 million people worldwide died of stroke, according to AHA statistics. In the US, stroke ranks fifth among all causes of death, with more than 160 000 deaths in 2020, based on data from the Centers for Disease Control and Prevention.
Alzheimer’s disease – the main cause of dementia – is the seventh-leading cause of death in the US. An estimated 6.5 million people age 65 and older have the condition, according to the Alzheimer’s Association. That number is expected to reach 12.7 million by 2050.
“The study is important because it gives additional information on how to lower CSVD risk, which may have an enormous public health benefit,” said Romero, an associate professor of neurology at Boston University School of Medicine who wrote an editorial published alongside the new research.
“It shows that we shouldn’t stop halfway. We should aim for achieving all the goals and achieving ideal cardiovascular health.”
Pan said the study was limited by incomplete dietary data and because it didn’t follow participants over a period of time. He called for larger, long-term observational studies to learn more about the relationship between CSVD and cardiovascular disease risk factors.
Romero said randomised clinical studies are needed to see whether controlling cardiovascular disease risk does indeed lower small vessel disease risk. He also called for future studies to evaluate the usefulness of screening high-risk people for CSVD using brain MRI.
In general, he said, health care professionals and health organisations need to come up with a clearer plan on how to fight CSVD.
“Often, there is no dedicated effort to control risk factors and track this consistently, particularly in patients that have high risk,” Romero said. “We really need to develop programs for effective and sustained implementation of these guidelines for preventing cardiovascular disease.”
