Posts tagged with "University College London"

The big chill: Low indoor temperatures are linked to higher blood pressure

March 5, 2019

If you are the one in your household who surreptitiously turns the heat down in order to save a little “cold cash,” think again. You soon could be paying the difference at the pharmacy.

It turns out that, while keeping your thermostat at 68 degrees (F) or lower during the daytime might reduce your financial burden, it could be straining your cardiovascular system. A recent study has linked cooler indoor temperatures to higher blood pressure.

According to a report by Study Finds, researchers at the University College London recently determined that for every one degree Celsius (1.8 degree Fahrenheit) decrease in indoor temperature, systolic blood pressure rises by an average of 0.48 mmHg, and diastolic blood pressure jumps about 0.45 mmHg. Systolic blood pressure measures the pressure in your blood vessels when your heart beats, whereas diastolic blood pressure measures the pressure in between beats. A blood pressure under 120/80 mmHg is considered normal.

“Our research has helped to explain the higher rates of hypertension, as well as potential increases in deaths from stroke and heart disease, in the winter months, suggesting indoor temperatures should be taken more seriously in diagnosis and treatment decisions, and in public health messages,” notes senior author Dr. Stephen Jivraj, of the UCL Institute of Epidemiology and Health Care, in a media release, adding, “Among other diet and lifestyle changes people can make to reduce high blood pressure, our findings suggest that keeping homes a bit warmer could also be beneficial.”

For the study, Dr. Jivraj’s team, evaluated data from 4,659 participants in the Health Survey for England. Individuals completed questionnaires on their general health and lifestyle choices; then, nurses followed up on the questionnaire by visiting the participants in their homes to measure their blood pressure and take indoor temperature readings. They found that average blood pressure for residents in the coolest homes was 126.64/74.52, whereas those in the warmest homes averaged 121.12/70.51 mmHg.

Researchers had to account for other factors such as social deprivation and outdoor temperature to identify independent associations between blood pressure and indoor temperature. The effect was especially notable in people who were less physically active.

Though the authors didn’t pinpoint a temperature for a “warm enough home,” they do suggest that 21 degrees (C) or about 70 degrees (F), is ideal.

“We would suggest that clinicians take indoor temperature into consideration, as it could affect a diagnosis if someone has borderline hypertension, and people with cooler homes may also need higher doses of medications,” says co-author Hongde Zhao.

The study was published in the Journal of Hypertension.

Research contact: @uclnews

Lost cause: Why do some people lack a sense of direction?

June 27, 2018

Could you get lost in a paper bag? Some of us have no “inner MapQuest.” We have such a poor sense of direction that one wrong turn can take us off the beaten path for hours.

Why can’t we navigate? In 2014, neuroscientist John O’Keefe won a Nobel Prize for Medicine, along with two of his students (May-Britt Moser and Edvard Moser) for a study on this very subject, conducted at University College London.

The research team discovered what they called “place cells” in the hippocampus, a part of the brain associated with memory. These place cells are activated when we go to a new area, forming a map of the environment. They combine with “grid cells” in the entorhinal cortex— which is next to the hippocampus—to tell us where we are, in relation to where we started out. In addition, the University College London researchers found a third type of “head-direction” cell in the entorhinal region, which fires off when we face in a certain direction.

In fact, the entorhinal cortex has been called the brain’s GPS system, based on a report on O’Keefe’s work in Scientific American. Together, these three types of specialized neurons—place cells, grid cells, and head-direction cells—enable each of us to navigate, but precisely how they do this is unclear.

What’s more, they may work differently in each of us. While our built-in compass is supposed to tell us which way we are facing—and then to provide directions on which way to turn in order to arrive at our chosen destination—if a person has a poor sense of direction, the signals are fuzzier. While the compass is supposed to readjust as a person moves through the environment, if he or she makes too many turns, the brain may not be able to keep up and may provide incorrect directions.

The researchers believe that men may have a slight directional advantage over women. Indeed, Dr. Martin Chadwick who did a follow-up study at University College London, told The Daily Mail UK, “Some studies have shown that women have a better visual memory: You can show them a scene and they will remember it better than men. Men, in contrast, can work with the geometry and rotate things in their mind better.”

Interestingly enough, the Daily Mail reported, when MRI brain scans were used to study the posterior hippocampus of candidates who were ready to take a test to qualify as London cabbies, those who had fully memorized London’s 25,000 streets and landmarks had a larger amount of gray matter in that region of the brain. The scientists think that their brains had changed in order to accommodate an internal “map” of the city, which would be used to direct them to the destinations requested by their riders.

Research contact: j.okeefe@ucl.ac.uk

Marriage may reduce the risk of dementia

November 30, 2017

Those of us who at some time in our lives have been “head over heels” for a partner or spouse probably are not headed for dementia in the future, according to findings of a study released on November 28.

Indeed, a paper published this week in the Journal of Neurology, Neurosurgery and Psychiatry asserts that individuals who always have been single have a 42% higher risk of developing dementia than people who are married or in a committed relationship. The study was based on 15 analyses with a cumulative cohort of over 800,000 patients.

Dementia—a decline in memory or cognition severe enough to reduce a person’s ability to perform everyday activities—usually occurs in older age. The most common form is Alzheimer’s disease.

Those who are widowed could have a 20% higher risk, the researchers determined. They could not examine whether the duration of being widowed or divorced had any influence on the findings.There was no similar risk found for those who had been divorced.

Marital status has the potential to affect dementia risk by increasing daily social interaction, the researchers found. Specifically, marriage may offer more opportunities for communications and contacts within the local community, which is associated with reduced dementia risk and reduced harmful lifestyle behaviors, they said.

They also determined that bereavement or divorce in people who have been married may promote dementia development through stress, which is pathogenic and associated with increased dementia risk.

By comparison, the health of unmarried Americans is worse than that of couples; being married is related to improved cancer survival; and widowhood is associated with disability in older people.13

That higher risk for singles remained even after researchers accounted for a person’s physical health, said Andrew Sommerlad, a research fellow and psychiatrist at University College London in Britain. That increased risk appeared to be similar to other known dementia risks, such as having diabetes or high blood pressure, he said.

“We don’t think that it is marriage itself or wearing a wedding ring which reduces people’s risk of dementia,” he told CNN recently.

“Instead, our research suggests that the possible protective effect is linked to various lifestyle factors which are known to accompany marriage, such as living a generally healthier lifestyle and having more social stimulation as a result of living with a spouse or partner,” he said.

Such factors as diet, physical activity, smoking and sleep also affect the risk.

The good news? As being unmarried becomes more of a social norm, it is likely that lifestyle differences between married and unmarried people are lessening, he researchers believe.

Research contacta.sommerlad@ucl.ac.uk