Multiple exposures to anaesthesia may affect your child’s memory

Agencies
June 1, 2017

Jun 1: A recent study has found that repeated exposure to a common anaesthesia drug early in life results in visual recognition memory impairment, which emerges after the first year of life and may persist long-term.child

The research from the Icahn School of Medicine at Mount Sinai is among the first to address the question of whether repeated postnatal anaesthesia exposure, in and of itself, results in memory impairment in a highly translationally relevant rhesus monkey model.

Rhesus monkeys at birth are at a stage of neurodevelopment that is more similar to that of human infants than are neonatal rodents; with respect to brain growth, a six-week-old rhesus monkey corresponds to a human 6 to 12 months of age.

Because these kinds of controlled studies cannot be carried out in humans, it is essential to use a comparable animal model to discover if anaesthesia is affecting the brain. Unlike previous research, the study was conducted in the absence of a surgical procedure, co-morbidities that may necessitate surgical intervention, or the psychological stress associated with illness.

“The major strength of this study is its ability to separate anaesthesia exposure from surgical procedures, which is a potential complication in the studies conducted in children,” said researcher Mark Baxter. “Our results confirm that multiple anaesthesia exposures alone result in memory impairment in a highly translational animal model. Interestingly, the anaesthesia-exposed group had normal visual memory at six months of age. Visual memory impairment didn’t emerge until the second year of life, corresponding roughly to the age of three to six years old in humans.”

Specifically, the study team exposed 10 non-human primate subjects to a common paediatric aesthetic called sevoflurane for four hours, the length of time required for a significant surgical procedure in humans. They were exposed to the aesthetic at postnatal day 7 and then again two and four weeks later, because human data indicate that repeated anaesthesia results in a greater risk of cognitive disability relative to a single aesthetic exposure.

They found the anaesthesia-exposed infants displayed no memory impairment when tested at 6-10 months, but demonstrated significant memory impairment (reduced time looking at the novel image) after the first year of life compared with the control group.

This primate model may be used by researchers for future studies to develop a new aesthetic agent or prophylactic treatment to counteract the impact of anaesthesia on behaviour in children. The findings also suggest that additional work is required to identify the mechanisms by which anaesthetics may cause long-term changes in central nervous system function that impact behaviour.

The study is published in The British Journal of Anaesthesia.

Comments

Add new comment

  • Coastaldigest.com reserves the right to delete or block any comments.
  • Coastaldigset.com is not responsible for its readers’ comments.
  • Comments that are abusive, incendiary or irrelevant are strictly prohibited.
  • Please use a genuine email ID and provide your name to avoid reject.
Agencies
January 11,2020

Europe, Jan 11: Researchers have revealed the people who drink tea at least three times a week have healthy years of life and longer life expectancy.

The research was published in the European Journal of Preventive Cardiology, a journal of the European Society of Cardiology (ESC).

Dr Xinyan Wang, who is the author of the study, said: "Habitual tea consumption is associated with lower risks of cardiovascular disease and all-cause death. The favourable health effects are the most robust for green tea and for long-term habitual tea drinkers."
The analysis that was conducted included about 100,902 participants of the China-PAR project2 with no history of heart attack, stroke, or cancer.

Participants were classified into two groups: Habitual tea drinkers and never or non-habitual tea drinkers and followed-up for a median of 7.3 years.

The analyses estimated that 50-year-old habitual tea drinkers would develop coronary heart disease and stroke 1.41 years later and live 1.26 years longer than those who never or seldom drank tea. Compared with never or non-habitual tea drinkers, the habitual tea consumers had a 20 per cent lower risk of incident heart disease and stroke, 22 per cent lower risk of fatal heart disease and stroke, and 15 per cent decreased risk of all-cause death.

The potential influence of changes in tea drinking behaviour was suspected in a subset of 14,081 participants with assessments at two-time points. The average duration between the two surveys was 8.2 years, and the median follow-up after the second survey was 5.3 years.

Habitual tea drinkers who maintained their habit in both surveys had a 39 per cent lower risk of incident heart disease and stroke, 56 per cent lower risk of fatal heart disease and stroke, and 29 per cent decreased risk of all-cause death compared to consistent never or non-habitual tea drinkers.

Senior author Dr Dongfeng Gu said: "The protective effects of tea were most pronounced among the consistent habitual tea drinking group. Mechanism studies have suggested that the main bioactive compounds in tea, namely polyphenols, are not stored in the body long-term. Thus, frequent tea intake over an extended period may be necessary for the cardioprotective effect."

In a subanalysis by type of tea, drinking green tea was linked with approximately 25 per cent lower risks for incident heart disease and stroke, fatal heart disease and stroke, and all-cause death. However, no significant associations were observed for black tea.
Dr Gu noted that a preference for green tea is unique to East Asia.

Two factors may be at play. First, green tea is a rich source of polyphenols which protect against cardiovascular disease and its risk factors including high blood pressure and dyslipidaemia. Black tea is fully fermented and during this process, polyphenols are oxidised into pigments and may lose their antioxidant effects. Second, black tea is often served with milk, which previous research has shown may counteract the favourable health effects of tea on vascular function.

Gender-specific analyses showed that the protective effects of habitual tea consumption were pronounced and robust across different outcomes for men, but only modest for women. Dr Wang said: "One reason might be that 48 per cent of men were habitual tea consumers compared to just 20 per cent of women. Secondly, women had a much lower incidence of, and mortality from, heart disease and stroke. These differences made it more likely to find statistically significant results among men."

She said: "The China-PAR project is ongoing, and with more person-years of follow-up among women the associations may become more pronounced."

In conclusion, the authors have found that randomised trials are required to validate the results and to illustrate nutritional guidelines and advice for lifestyle.

Comments

Add new comment

  • Coastaldigest.com reserves the right to delete or block any comments.
  • Coastaldigset.com is not responsible for its readers’ comments.
  • Comments that are abusive, incendiary or irrelevant are strictly prohibited.
  • Please use a genuine email ID and provide your name to avoid reject.
News Network
March 6,2020

Mar 6: The spread of the new coronavirus is shining the spotlight on a little-discussed gender split: men wash their hands after using the bathroom less than women, years of research and on-the-ground observations show.

Health officials around the world advise that deliberate, regular handwashing is one of the best weapons against the virus which causes a flu-like respiratory illness that can kill and has spread to around 80 countries.

The Centers for Disease Control and Prevention's online fact sheet "Handwashing: A corporate activity," cites a 2009 study that finds "only 31% of men and 65% of women washed their hands" after using a public restroom.

Social media comments about men's handwashing lapses forced an august British institution to caution visitors about bathroom behaviour this week.

After author Sathnam Sanghera complained on Twitter about "grown," "educated" men in the British Library toilets not washing their hands, the library responded, putting up additional signs reminding patrons to wash their hands in men's and women's bathrooms.

Thanks to "visitor feedback," a spokesman told Reuters, "we have increased further the number of posters in public toilets so that visitors are reminded of the importance of good hygiene at exactly the point where they can wash their hands."

Men and women approach handwashing after using the restroom differently, according to multiple surveys and field studies.

"Women wash their hands significantly more often, use soap more often, and wash their hands somewhat longer than men," according to a 2013 Michigan State University field study conducted by research assistants who observed nearly 4,000 people in restrooms around East Lansing, Michigan.

The study found 14.6% of men did not wash their hands at all after using the bathroom and 35.1% wet their hands but did not use soap, compared to 7.1% and 15.1% of women, respectively.

"If you stand in the men's bathroom at work, and watch men leave, they mostly don't wash their hands if they used the urinal," said one New York City public relations executive, who did not want to be identified for fear of alienating his colleagues.

Since the virus's spread, he's seen an uptick in men's handwashing at work, he noted. "I, for the record, do wash my hands all the time," he added.

Female medical staff in critical care units "washed their hands significantly more often than did their male counterparts after patient contact," a 2001 study published in the American Journal of Infection Control found.

Middle-aged women with some college education had the highest level of knowledge about hand hygiene, a survey published in 2019 by BMC Public Health, an open access public health journal, found.

Early information about coronavirus infection in China shows that men may be more susceptible to the disease. Just over 58% of the more than 1,000 COVID-19 patients reported in China through Jan. 29, 2020, were male, research published in the New England Journal of Medicine shows.

Researchers have not linked the difference to hand hygiene.

Comments

Add new comment

  • Coastaldigest.com reserves the right to delete or block any comments.
  • Coastaldigset.com is not responsible for its readers’ comments.
  • Comments that are abusive, incendiary or irrelevant are strictly prohibited.
  • Please use a genuine email ID and provide your name to avoid reject.
Agencies
June 29,2020

Washington DC, Jun 29: Young children with narrow retinal artery diameters were more likely to develop higher blood pressure, and children with higher blood pressure levels were more likely to develop retinal microvascular impairment during early childhood, according to a new study.

The first study to show this connection in children was published today in Hypertension, an American Heart Association journal.

High blood pressure, the main risk factor for the development of cardiovascular disease (CVD), can manifest as early as childhood, and the prevalence of high blood pressure among children continues to rise. In previous studies, analysis of blood vessels in the retina has shown promise as a predictor of CVD risk among adults. In the study titled, "Retinal Vessel Diameters and Blood Pressure Progression in Children," researchers sought to predict the development of high blood pressure in children over four years based on retinal blood vessel measurements.

"Hypertension continues as the main risk factor for the development of cardiovascular diseases and mortality," says Henner Hanssen, M.D., the study's lead author and a professor in the department of sport, exercise and health at the University of Basel in Switzerland. 

"Primary prevention strategies are needed to focus on screening retinal microvascular health and blood pressure in young children in order to identify those at increased risk of developing hypertension. The earlier we can provide treatment and implement lifestyle changes to reduce hypertension, the greater the benefit for these children."

Researchers screened 262 children ages six to eight from 26 schools in Basel, Switzerland, in 2014, for baseline blood pressure and retinal arterial measurements. Both measures were taken again in 2018. Blood pressure measurements at both baseline and follow-up were performed in a sitting position after a minimum of five minutes of rest and were categorized based on the American Academy of Pediatrics' blood pressure guidelines. These guidelines utilize the same measurements as the American Heart Association/American College of Cardiology 2017 Guideline for the Prevention, Detection, Evaluation, and Management of High Blood Pressure in Adults.

Results from the analysis indicate: children with narrower retinal vessel diameters at baseline developed higher systolic blood pressure at follow-up; retinal vessel diameters could explain 29 -31 per cent of the changes in systolic blood pressure progression between 2014 and 2018; children with higher blood pressure levels at baseline developed significantly narrower arteriolar diameters at follow-up, depending on weight and cardiorespiratory fitness; and initial blood pressure measures explained 66-69 per cent of the change in retinal arteriolar diameter from baseline to follow-up.

"Early childhood assessments of retinal microvascular health and blood pressure monitoring can improve cardiovascular risk classification. Timely primary prevention strategies for children at risk of developing hypertension could potentially counteract its growing burden among both children and adults," said Hanssen.

Researchers noted limitations of their study include that they could not confirm blood pressure measurements over a single 24-hour period, so they would not account for "white coat" hypertension, a condition where patients have high blood pressure readings when measured in a medical setting.

Developmental stage including puberty status of each child was not accounted for in the study, as well as genetic factors or birth weight - variables that could impact blood pressure development and microvascular health.

In addition, reference values for appropriate retinal vessel diameters in children do not currently exist, so future studies are needed to determine age-related normal values during childhood.

Comments

Add new comment

  • Coastaldigest.com reserves the right to delete or block any comments.
  • Coastaldigset.com is not responsible for its readers’ comments.
  • Comments that are abusive, incendiary or irrelevant are strictly prohibited.
  • Please use a genuine email ID and provide your name to avoid reject.