Medical Bulletin 20/ December/ 2024 - Video

A recent study from National Hospital Organization Kyoto Medical Center explored the connection between subjective walking speed and metabolic diseases risk, particularly in individuals with obesity. The study’s findings, published in Scientific Reports suggest that assessing how a person perceives their walking pace relative to peers could become a vital tool for public health.

The study involved 8,578 individuals with obesity, 9,626 individuals with high waist circumference, and 6,742 meeting both criteria. The participants were asked a single question in a health questionnaire: “Is your walking speed faster than that of your age and sex?” Based on their responses, they were categorized as either “fast” or “slow” walkers. The results showed that individuals who identified as faster walkers had significantly lower risks of diabetes (30% lower) and smaller but notable reductions in the risks of hypertension and dyslipidemia.

The simplicity and accessibility of this measure makes it ideal for application in clinical and public health settings. Subjective walking speed is self-reported and readily incorporated into standard examinations unlike objective walking speed, which needs resources, time, and space to assess.

The researchers attributed their findings to the relationship between walking speed and overall health. Faster walkers often demonstrate better cardiorespiratory fitness, which is associated with lower levels of inflammation and oxidative stress—two key drivers of metabolic diseases.

According to the study, individuals who walk quickly may be more fit and have a lower risk of metabolic diseases. In addition to lowering the risk of metabolic diseases, encouraging faster walking, even subjectively, could help prevent the “metabolic domino effect,” where obesity leads to lifestyle-related diseases. Obesity is the first step in this cascade, which then advances to diseases like dementia and cardiovascular disease.

Reference: Yamamoto, Y., Ikeue, K., Kanasaki, M. et al. Association between subjective walking speed and metabolic diseases in individuals with obesity: a cross-sectional analysis. Sci Rep 14, 28228 (2024). https://doi.org/10.1038/s41598-024-78541-w

A new study pinpoints the age when cardiovascular health (CVH) trajectories begin to decline, revealing a crucial window for targeted interventions to improve cardiovascular health into adolescence and adulthood.

The findings are published in JAMA Cardiology.

Key Takeaways from the study are:

A new study led by the Harvard Pilgrim Health Care Institute sheds light on the trajectory of cardiovascular health (CVH) early in life, which may contribute to its disparities in adulthood.

Across demographic subgroups, cardiovascular health scores begin to decline at approximately 10 years of age and appear driven by health behaviors rather than health factors.

Key health behaviors to target for improving early-life cardiovascular health include better sleep, healthier diet, and reducing smoking.

“Though we know that better heart health in childhood is linked to lower risks of coronary issues later in life, the current state of cardiovascular health in US children is less than ideal,” said lead author Izzuddin Aris, Harvard Medical School assistant professor of population medicine at the Harvard Pilgrim Health Care Institute. “Our study provides insight into the trajectory of cardiovascular health in early life, establishing a clear window of opportunity to improve the health of the nation’s children now and into the future.”

The American Heart Association’s recently introduced Life’s Essential 8 guidelines assess cardiovascular health based on four behavioral (diet, smoking, physical activity, sleep duration) and four health factors (body mass index, blood pressure, blood sugar and cholesterol levels). Using the Life’s Essential 8 construct, the research team studied data from over 1,500 children from the Project Viva pre-birth cohort in eastern Massachusetts. Participant inclusion required information on at least 3 cardiovascular health metrics in early childhood or at least 4 metrics in mid-childhood, early adolescence, or late adolescence. The team assessed 6 CVH metrics in early childhood (diet, smoking, physical activity, sleep duration, BMI, and BP), and up to 8 from mid-childhood to late adolescence.

The authors found that cardiovascular health scores start to decline around age 10 across all demographic groups, driven by health behaviors rather than health factors. This decline may reflect social and/or developmental changes that typically occur at this age—such as changes in school schedules that may interfere with meeting guidelines for healthy sleep duration and/or diet—and may affect health behaviors. Improving these health behaviors, especially between mid-childhood and early adolescence, could help optimize cardiovascular health.

They also noted small but significant differences in cardiovascular health trajectories based on maternal socioeconomic status and child race and ethnicity.

Reference: Aris IM, Rifas-Shiman SL, Perng W, et al. Trajectory of Cardiovascular Health Across Childhood and Adolescence. JAMA Cardiol. Published online December 18, 2024. doi:10.1001/jamacardio.2024.4022

A new study in Journal of Dental Research that examines how cognitive development among young children is affected by early exposure to fluoride. The study aimed to investigate potential effects of fluoride exposure on cognitive neurodevelopment assessed with the Wechsler Adult Intelligence Scale 4th edition (WAIS-IV) in an Australian population-based sample.

“The fluoridation of drinking water has been enormously beneficial to oral health over the decades, and to public health more generally,” said AADOCR President Effie Ioannidou. “It is crucial that a wealth of scientific evidence always be available should the public ever need reminding of this fact.”

The sample was selected from the National Child Oral Health Study (NCOHS) 2012-14. NCOHS collected data on socioeconomic factors, oral health behaviors, and residential history to estimate percent lifetime exposure to fluoridated water during the first five years of life. NCOHS children were also examined by trained and calibrated examiners to assess dental fluorosis. The sample was followed up in 2022-23 to collect data on cognitive neurodevelopment using the WAIS-IV, which was administered by trained and calibrated qualified psychologists.

Multivariable regression models were generated to investigate associations between the two exposure measurement with full-scale IQ scores, controlling for important confounding effects.

The study provided consistent evidence that early childhood exposure to fluoride does not have effects on cognitive neurodevelopment.

Reference: Do LG, Sawyer A, John Spencer A, et al. Early Childhood Exposures to Fluorides and Cognitive Neurodevelopment: A Population-Based Longitudinal Study. Journal of Dental Research. 2024;0(0). doi:10.1177/00220345241299352

A review of some 3,000 studies suggests that minute plastic air particles may cause serious health problems. These include male and female infertility, colon cancer and poor lung function. The particles also may contribute to chronic pulmonary inflammation, which can increase the risk of lung cancer. The findings are published in environmental science and technology.

“These microplastics are basically particulate matter air pollution, and we know this type of air pollution is harmful,” said Tracey J. Woodruff, PhD, MPH, a professor of obstetrics, gynecology and reproductive sciences at UCSF.

Microplastics are less than 5 millimeters – smaller than a grain of rice – and they are ubiquitous in the environment. Each year, companies around the world produce nearly 460 million metric tons of plastic. That is projected to reach 1.1 billion by 2050.

A major source of plastic in the air is driving. Friction wears down tires along with the road surface, sending plastic fragments into the air. The paper is the first systematic review of microplastics using gold standard methods approved by the National Academy of Sciences.

Most of the studies in the review were based on animals. But the researchers said the conclusions likely also apply to humans since they share many of the same exposures.

Reference: Effects of Microplastic Exposure on Human Digestive, Reproductive, and Respiratory Health: A Rapid Systematic Review, Nicholas Chartres, Courtney B. Cooper, Garret Bland, Katherine E. Pelch, Sheiphali A. Gandhi, Abena BakenRa, and Tracey J. Woodruff, Environmental Science & Technology Article ASAP, DOI: 10.1021/acs.est.3c09524