Archive for month: November, 2024

A vigorous workout does more to suppress hunger levels in healthy adults than does moderate exercise, and females may be especially susceptible to this response, according to a small study published in the Journal of the Endocrine Society.

The study examines the effects of exercise intensity on ghrelin levels and appetite between men and women. Ghrelin is known as the “hunger hormone” and is associated with perceptions of hunger.

“We found that high intensity exercise suppressed ghrelin levels more than moderate intensity exercise,” said lead author Kara Anderson, Ph.D., of the University of Virginia and the University of Virginia Health System in Charlottesville, Va. “In addition, we found that individuals felt ‘less hungry’ after high intensity exercise compared to moderate intensity exercise.”

Ghrelin circulates in acylated (AG) and deacylated (DAG) forms, which are known to affect appetite. Data on the impact of exercise intensity on AG and DAG levels, and their effects on appetite, is sparse and primarily limited to males, the study noted.

To address this shortfall, the study examined eight males and six females. Participants fasted overnight and then completed exercises of varying intensity levels, determined by measurements of blood lactate, followed by self-reported measurements of appetite.

Females had higher levels of total ghrelin at baseline compared with males, the study noted. But only females demonstrated “significantly reduced AG” following the intense exercise, according to the findings.

“We found that moderate intensity either did not change ghrelin levels or led to a net increase,” the study noted. These findings suggest that exercise above the lactate threshold “may be necessary to elicit a suppression in ghrelin.”

Researchers also acknowledged that more work is needed to determine the extent to which the effects of exercise differ by sex.

Ghrelin has been shown to have wide-ranging biological effects in areas including energy balance, appetite, glucose homeostasis, immune function, sleep, and memory.

“Exercise should be thought of as a ‘drug,’ where the ‘dose’ should be customized based on an individual’s personal goals,” Anderson said. “Our research suggests that high-intensity exercise may be important for appetite suppression, which can be particularly useful as part of a weight loss program.”

Reference:

Kara C Anderson, Tana Mardian, Benjamin Stephenson, Emily E Grammer, Macy E Stahl, Nathan R Weeldreyer, Zhenqi Liu, Kaitlin M Love, Sibylle Kranz, Jason D Allen, Arthur Weltman, The Impact of Exercise Intensity and Sex on Endogenous Ghrelin Levels and Appetite in Healthy Humans, Journal of the Endocrine Society, Volume 8, Issue 11, November 2024, bvae165, https://doi.org/10.1210/jendso/bvae165

AI-based model may help in early detection of ectopic tooth eruptions, suggests a study published in the Journal of Dentistry.

 A study was conducted to construct a diagnostic model for mixed dentition using a multistage deep-learning network to predict potential ectopic eruption in permanent teeth by integrating dentition segmentation into the process of automatic classification of dental development stages. A database was established by reviewing 1576 anonymous panoramic radiographs of children aged 6–12 years, collected at the Stomatology Hospital, xxxxxx. These radiographs were categorised as normal or ectopic eruption, with expert diagnoses serving as a benchmark for training and evaluating artificial intelligence (AI) models. Furthermore, tooth boundaries and dental development stages were manually annotated by three pediatric dentistry experts. The dataset was split into training, validation, and test sets at an 8:1:1 ratio.Results: The diagnostic performance of the deep-learning model was rigorously evaluated. The model demonstrated accuracy in tooth segmentation, with Intersection over Union, precision, sensitivity, and F1 scores of 0.959, 0.993, 0.966, and 0.979, respectively. Furthermore, its ability to identify tooth ectopic eruptions on panoramic radiographs, when compared to evaluations by three dentists. Based on McNemar’s test, the model’s specificity and accuracy in identifying ectopic tooth eruptions on the test dataset surpassed that of Dentist 1 (P < 0.05), while no significant difference was observed compared to the other two dentists. Besides, the deep learning model also showed its potential in classifying dental development stages, as tested against three different standards.

When older adults have significant year-to-year fluctuations in their cholesterol levels without changes in medication, it could indicate an increased risk of developing dementia or cognitive decline, according to a preliminary study to be presented at the American Heart Association’s Scientific Sessions 2024.

The meeting, Nov. 16-18, 2024, in Chicago, is a premier global exchange of scientific advancements, research and evidence-based clinical practice updates in cardiovascular science.

“Older people with fluctuating cholesterol levels unrelated to whether they were taking lipid-lowering medications – particularly those experiencing big year-to-year variations — may warrant closer monitoring and proactive preventive interventions,” said lead author Zhen Zhou, Ph.D., a postdoctoral research fellow in the School of Public Health and Preventive Medicine at Monash University in Melbourne, Australia.

The current project used the in-trial and post-trial data of participants enrolled in a randomized clinical trial called ASPirin in Reducing Events in the Elderly (ASPREE) that determined low-dose aspirin was not effective for reducing heart disease risk in Australian and American adults. While one-third were taking cholesterol-lowering medication, none of the almost 10,000 participants started, stopped or changed lipid-lowering medication during the follow-up period.

All participants were relatively healthy adults without dementia who had been having their cholesterol levels monitored annually. The first three cholesterol measurements taken in the ASPREE study were used to determine how much each person’s lipid levels varied from year to year.

During almost six years of follow-up after the yearly assessments, 509 participants developed dementia and another 1,760 developed cognitive decline without dementia.

Compared with those who had the most stable cholesterol levels, the study found:

High fluctuations (in the top 25%) in total cholesterol were associated with a 60% increase in dementia and a 23% increase in cognitive decline.

Low-density lipoprotein cholesterol (LDL cholesterol or “bad” cholesterol) and total cholesterol fluctuations were associated with significantly faster declines in overall cognitive health test scores and tests involving memory and reaction speed.

High fluctuations in high-density lipoproteins (HDL “good” cholesterol) or triglycerides were not associated with dementia or cognitive decline. Triglycerides are the most common type of fat in the body, storing excess energy from food.

“We need future studies to help us understand the relationship between cholesterol variability and dementia risk,” Zhou said. “Are cholesterol variability levels a real risk factor, a precursor or a biomarker of dementia risk? One possible explanation is that significant fluctuations in total and LDL cholesterol levels may destabilize atherosclerotic plaques, which are mostly composed of LDL cholesterol. This destabilization can raise the risk of plaque growth, rupture and subsequent obstruction of blood flow in the brain, which may therefore impact brain function.”

The study had some limitations, including that cholesterol readings can vary for many reasons, and the connection between cholesterol variability and dementia risk may be affected by these unanalyzed factors. In addition, the study participants were mostly white adults (96%), so, the findings may not apply to people in other population groups. As an observational study, it cannot prove a cause-and-effect relationship between cholesterol fluctuations and dementia risk.

“If future research confirms a cause-and-effect relationship, reducing cholesterol variability could potentially be a promising therapeutic target for dementia,” Zhou said. “Importantly, our results should not be misinterpreted as suggesting that lowering cholesterol through lifestyle modification or lipid-lowering medications is harmful for brain health.”

Based on data from 2017 to 2020, 63.1 million or 25.5%, of U.S. adults had high “bad” cholesterol levels (130 mg/dL or higher). Globally, in 2021, 3.72 million deaths were attributed to excessive “bad” cholesterol levels, according to the American Heart Association’s Heart Disease and Stroke Statistics 2024 Update.

“In the past, studies have focused on the connection between individual vascular risk factors and cognitive decline. However, there is evidence that an increase in the variability of certain functions in the body, such as blood pressure or blood sugar levels, can be harmful to both the heart and the brain,” said American Heart Association volunteer expert, Fernando D. Testai M.D., Ph.D., FAHA, a professor of neurology and rehabilitation at the University of Illinois Chicago, who also served as chair for the Association’s recent “Cardiac Contributions to Brain Health” scientific statement. “This study adds an important piece to the puzzle of preserving brain health by providing evidence that increasing variability in cholesterol levels is associated with cognitive decline. The study did not include people who started or stopped taking lipid-lowering medications during the study period. So, the results cannot be explained by the effect of statins. From a practical standpoint, not sticking to strategies that improve the lipid profile, such as following a healthy diet and exercising, can worsen the negative impact of harmful lipids on the brain.”

Taiwan: A recent study published in the European Heart Journal confirmed the link between pregnancy and an increased risk of aortic events. The study revealed that pregnant women face an increased risk of aortic events from the onset of pregnancy through the first year postpartum.

A new study revealed that Mesalamine, an anti-inflammatory drug, can effectively treat postinfectious irritable bowel syndrome (PI-IBS) symptoms and improve the quality of life. The study results were published in the journal Neurogastroenterology & Motility. 

Irritable bowel syndrome (IBS) is a common gastrointestinal disorder characterized by abdominal pain and alteration in bowel frequency or consistency in the absence of a gross structural or biochemical abnormality. Postinfectious irritable bowel syndrome ((PI-IBS) is a condition associated with low-grade intestinal inflammation. It develops in a subset of patients after gastroenteritis. Previous studies showed that long-acting Mesalamine can be used to treat IBS. Hence, researchers conducted a study to investigate the efficacy of long-acting Mesalamine in individuals with PI-IBS particularly those with diarrhea-predominant IBS (IBS-D) following gastroenteritis, as PI-IBS is linked to low-grade intestinal inflammation.

Also Read: IBS following gastroenteritis may last more than four years in around half of those affected, reveals research.

A Randomized double-blind placebo-controlled study was carried out on a total of 61 patients who developed IBS-D after gastroenteritis. Individuals were randomly assigned to receive either 2.4 g of long-acting mesalamine or a placebo daily for 8 weeks. The study assessed symptoms including abdominal pain, bloating, stool frequency, stool consistency, severity of diarrhea and constipation, satisfaction with bowel habits, and how much IBS affected or interfered with life. Quality of life (QOL) was measured using the IBS-QOL questionnaire. The primary outcome was the overall bowel symptom score (BSS) after 8 weeks of treatment. Effect sizes were quantified using standardized mean differences (Cohen’s d).

Findings:

• Of the 61 participants, 54 completed the 8-week study with 28 in the mesalamine group and 26 in the placebo group.
• The majority of participants (91%) were male, with an age range of 23–71 years (mean ± SD: 43 ± 13 years).
• Mesalamine showed greater efficacy than placebo in reducing overall BSS, with a medium effect size (Cohen’s d = 0.57, p = 0.042).
• A significant improvement in the secondary outcomes was noticed on how IBS affects daily life (d = 0.72, p = 0.01).
• For the individual IBS symptoms, all seven symptoms assessed showed trends favoring mesalamine, and eight of nine IBS-QOL subscales also showed trends indicating mesalamine’s superiority.

Also Read: Exposure to rotavirus-associated hospitalization tied to heightened autoimmune disease risk

In patients with PI-IBS, long-acting mesalamine was effective in reducing IBS symptoms and improving quality of life suggesting that mesalamine could be a promising treatment option for managing PI-IBS.

Take-home Points:

• This placebo-controlled randomized trial assessed the efficacy of 2.4 g of long-acting mesalamine for the treatment of postinfectious diarrhea-predominant IBS.
• Among 54 patients who underwent 8-week treatment, mesalamine resulted in greater improvements on the Bowel Symptoms Score (change, −13 vs −4; P = .042); however, the difference between mesalamine and placebo was no longer significant when the constipation subscore was removed.
• Apart from the Bowel Symptoms Score, mesalamine largely failed to demonstrate superiority to placebo for other measures of symptom severity and QoL measures.
• Mesalamine may have some role in improving overall symptom severity in postinfectious IBS; however, additional larger studies are needed.

Further reading: Tuteja, Ashok K et al. “Randomized double-blind placebo-controlled study to evaluate the effect of long-acting mesalamine on postinfectious irritable bowel syndrome with diarrhea.” Neurogastroenterology and motility, e14889. 5 Aug. 2024, doi:10.1111/nmo.14889