Tag: inequality

Categories : Diseases, Syndromes and Conditions Environmental EffectsTags :

Wealth Divide, not Vitamin D, Explains Differing MS Rates

On By ModernMedia
Photo by Kyle Glenn on Unsplash

Differences in vitamin D exposure have been thought to explain why people who live farther from the equator are more likely to develop multiple sclerosis (MS). But countries farther from the equator are also more likely to be wealthier. A new analysis published in Neurology shows that the amount a country spends on health care may help explain this relationship between MS and latitude.

According to study author Deanna Saylor, MD, MHS, the results suggest that MS rates may be greatly underestimated in low-income countries with lower health care spending, which means that people have less access to neurologists who have the expertise to diagnose MS and MRI scanners that are needed to make the diagnosis.

Researchers analysed data from scientific studies and databases to determine current rates of MS in 203 countries and territories. Countries were then grouped into world regions and by income levels.

Rates of MS varied by region and income level. For example, in high-income countries an average of 46 of every 100 000 people had MS, compared to 10 people per 100 000 in low-income countries. Health care spending per capita was $2805 for high-income countries, compared to $45 in low-income countries.

For each location, researchers examined gross domestic product per capita, current health expenditure per capita, income levels, the availability of brain scans to diagnose MS, the number of neurologists per capita and universal health care. They also reviewed lifestyle factors such as obesity and tobacco use.

Once the researchers adjusted the data for other factors that could affect the risk of MS, such as age and sex, they found that health care spending and latitude were strongly associated with MS rates. The research showed that, with every increase of one standard deviation in health expenditure per capita, a country’s MS prevalence increased by 0.49. Alternatively, with every increase of one standard deviation in latitude, a country’s MS prevalence increased by 0.65.

Researchers also found that health care spending explained some, but not all, of the link between latitude and MS. After adjusting for other factors, the link between latitude and MS decreased by more than 20% when health care expenditure per capita was considered.

The availability of universal health care was associated with rates of MS in all world regions, except Southeast Asia, with universal health care tied to higher rates of MS.

In high-income countries, rates of MS were linked to most factors, including gross domestic product per capita, current health expenditure per capita, and the number of neurologists, but not tobacco use and obesity or the number of MRI units per capita. However, in low-income countries, there were no associations with any of these factors, which may be explained by a lack of significant variation in data from these countries, Saylor said.

According to Dr Saylor, the finding that current health expenditure per capita was very strongly linked with national rates of MS further supports the hypothesis that greater investment in health care leads to more robust reporting of rates of MS. She also said the minimal links between rates of MS and lifestyle factors such as tobacco use and obesity run counter to prior assumptions that lifestyle and consumption behaviours explain the large portions of regional differences in reported rates of MS.

Dr Saylor said strategies are urgently needed for the accurate assessment of the burden of MS in low-income countries, and these lower reported MS can obscure the need for training and funding regarding MS.

A limitation of the study is that different data sources may have collected information during different time periods or used different methods, which could affect the accuracy of estimates.

Source: American Academy of Neurology

Categories : Gender GeneticsTags :

Study Finds Testosterone’s Importance for Success Overrated

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Ball-and-stick model of the testosterone molecule, C19H28O2, as found in the crystal structure of testosterone monohydrate. Credit: Ben Mills, Wikimedia Commons.

With the Olympics underway, testosterone is again in the spotlight over its role in enhancing physical performance, with rules about its natural level being once again debated. It has also been popularly thought to be involved in success in other endeavours – but its importance in this regard may be overrated.

New research has found little evidence that testosterone exerts a meaningful influence on successes in life for men or women. The study in fact suggests that testosterone’s importance outside of physical endeavours could be even less important than previously believed.

In men, it is known that testosterone is linked to socioeconomic position, such as income or educational qualifications.  Researchers from the University of Bristol’s Population Health Sciences (PHS) and MRC Integrated Epidemiology Unit (IEU) set out to determine whether this is because testosterone has an influence on socioeconomic position, as opposed to socioeconomic circumstances affecting testosterone levels, or if it was a case of health affecting both. The findings are published in Science Advances.

To isolate effects of testosterone itself, the investigators used Mendelian randomisation in a sample of 306,248 UK adults from UK Biobank. They explored testosterone’s influence on socioeconomic position, including income, employment status, neighborhood-level deprivation, and educational qualifications; on health, including self-rated health and BMI, and on risk-taking behaviour.  

Dr Amanda Hughes, Senior Research Associate in Epidemiology in Bristol Medical School: Population Health Sciences (PHS), said: “There’s a widespread belief that a person’s testosterone can affect where they end up in life. Our results suggest that, despite a lot of mythology surrounding testosterone, its social implications may have been over-stated.”

First, the team identified genetic variants linked to higher testosterone levels, and explored their links to outcomes. Since genetic variations are essentially fixed throughout a lifetime, it is highly unlikely that they are affected by socioeconomic circumstances, health, or other environmental factors.

In common with prior studies, multivariate analysis showed men with higher testosterone had higher household income, lived in less deprived areas, and were more likely to have a university degree and a skilled job. Higher testosterone in women was linked to lower socioeconomic position, including lower household income, living in a more deprived area, and lower chance of having a university degree. Consistent with previous evidence, higher testosterone was associated with better health for men and poorer health for women, and greater risk-taking behaviour for men.

In contrast, the Mendelian randomisation method showed there was little evidence that the testosterone-linked genetic variants were associated with any outcome for men or women. The research team concluded that there is little evidence that testosterone meaningfully affected socioeconomic position, health, or risk-taking in men or women. The study suggests that – despite the mythology surrounding testosterone – its importance is much less than previously held.

Since the results for women were less precise than the men’s, the influence of testosterone in women could be further explored with larger sample sizes.  

Dr Hughes added: “Higher testosterone in men has previously been linked to various kinds of social success. A study of male executives found that testosterone was higher for those who had more subordinates. A study of male financial traders found that higher testosterone correlated with greater daily profits. Other studies have reported that testosterone is higher for more highly educated men, and among self-employed men, suggesting a link with entrepreneurship.

“Such research has supported the widespread idea that testosterone can influence success by affecting behaviour. There is evidence from experiments that testosterone can make a person more assertive or more likely to take risks – traits which can be rewarded in the labor market, for instance during wage negotiations. But there are other explanations. For example, a link between higher testosterone and success might simply reflect an influence of good health on both. Alternatively, socioeconomic circumstances could affect testosterone levels. A person’s perception of their own success could influence testosterone: in studies of sports matches, testosterone has been found to rise in the winner compared to the loser.”

Source: University of Bristol

Journal information: Testosterone and socioeconomic position: Mendelian Randomization in 306,248 men and women in UK Biobank’, Science Advances (2021).

Categories : AgeingTags :

Hearing Loss in Older People Can be Prevented While Young

On By ModernMedia
Photo by JD Mason on Unsplash

Based on a new model, researchers have proposed a way to prevent hearing loss in older people by addressing socioeconomic inequalities encountered while young.

The model developed by University of Manchester researchers could have an impact on the estimated 466 million people worldwide with disabling hearing loss, which mostly affects the elderly.

Published in Trends in Hearing, this is the first study examining the mechanisms and explaining the relationship between a lifetime of socioeconomic inequalities and hearing health.

Previous studies have shown that people with hearing loss are more likely to have poorer educational achievement, higher rates of unemployment and lower annual family income compared to those with other health conditions.

They are also more likely to have long-term health conditions and a higher overall disease burden than older people without hearing loss.

Lead researcher Dr Dalia Tsimpida said: “Hearing deterioration is a lifelong process but not an inevitable result of aging. Understanding this process is an essential step in addressing the global burden of hearing loss.”

Dr Tsimpida, a postdoctoral researcher at the University’s Institute for Health Policy and Organization (IHPO), added: “The key determinants of poor hearing health in the course of a life and their interdependency as described by this model is a powerful way to intervene in this major problem.

“Our focus is not simply on the age of older adults but on factors which impact on people earlier in life, which if modified could reduce hearing loss in older age.”

“This approach in hearing health can lead to the development of appropriate interventions and public health strategies that can have significant health policy and practice implications.”

Study co-author Dr Maria Panagioti said: “This model provides now a visual representation of the several modifiable factors of hearing loss in distinct life stages and their evolution over time, which is new thinking in hearing loss research.

“Given the burden of adult-onset hearing loss, such a conceptual tool for hearing health inequalities has the potential of improving the physical, mental and social wellbeing of individuals.”

Source: Medical Xpress

Journal information: Dialechti Tsimpida et al, Conceptual Model of Hearing Health Inequalities (HHI Model): A Critical Interpretive Synthesis, Trends in Hearing (2021). DOI: 10.1177/23312165211002963