Tag: 10/9/21

Rare Diseases in South Africa: A Neglected Topic

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An article in Spotlight examines the challenges faced by South Africans with rare diseases.

A rare disease is a health condition affecting a small number of people compared with other diseases commonly identified in the population. According to the World Health Organization (WHO), there are between 5000 and 8000 known rare diseases worldwide, affecting an estimated 400 million people.

According to the advocacy group Rare Disease South Africa (RDSA), about 3.6 million people in SA have a rare disease. In South Africa, the ability to diagnose a rare disease is hindered by a lack of capacity and resources, according to research, putting the time to diagnosis for rare diseases in general higher than the estimated 5.5 to 7.5 years in high-income countries.
“There is still low recognition of genetic disorders among specialists. And when they are recognised, testing remains expensive and requires sophisticated levels of training which are relatively limited,” says Prof Karen Fieggen, a medical geneticist at the University of Cape Town (UCT).

According to her, costs, skills, training, and human resource factors are all barriers to effective testing and diagnosis. But she says the rationale to build an effective system is solid.

“We have capable people and expertise to build this system, but until you invest in it, it won’t be big enough to be self-sustaining,” she says.

Prof Fieggen acknowledges that resources are stretched in the public sector, where specialists who carry out genetic testing for rare diseases must meet the needs of a larger part of the population. However, she notes, “there’s no guarantee you’re better off in the private sector”.

“There are very few genetic referral options, and none of the medical geneticists are kept in work full time,” she says. In Cape Town, for example, she says that all patients seeking genetic testing had to come to the private sector until recently. “We have the capacity to train seven specialists a year, but posts aren’t available for them to take,” she says.

At one per 4.5 million population, available medical geneticists in the public healthcare sector fall far short of the 21 per 2 million recommended by the WHO. These services are also spread unevenly through the country. The country’s heavy burden of HIV and TB is partly responsible for this lack of coverage.

While healthcare training must focus on these public health needs, Prof Fieggen says rare diseases need a sensible approach. “It doesn’t help to throw huge resources at something that will have minimal management impact,” she says. “But the way in which rare diseases have been relatively ignored isn’t constructive.”

Helping the recognition of rare diseases and referral pathways in physician training may make a difference. “One thing that could be instilled in training is to recognise that if things are atypical in their presentation, there should be a discussion with a referral centre,” says Associate Professor Ian Ross, a senior consultant endocrinologist at UCT and Groote Schuur Hospital.

Only 2.5-5% of rare diseases have approved treatments, some of which are prohibitively expensive.

The most expensive drug in the world is Zolgensma (generic name onasemnogene abeparvovec), a once-off treatment costing a mind-blowing USD $2.1 million (R 30m). Used to treat inherited spinal muscular atrophy, where infants with the condition are unlikely to see their second birthday. However, even this is available through the UK’s National Health Service, which struck a deal to bring prices down.

Du Plessis says these drugs are not on the essential medicines list because of the small group of patients they would serve. “The essential medicines list is dedicated to treatments that are procured in large numbers. Rare diseases will never be mass-market drugs.”

Such drugs can be purchased by hospital pharmacists so they can be available at a certain hospital, making for a haphazard situation.
To help address this inequality, RDSA held a Rare Disease Symposium on 25 August, inviting feedback on a draft policy framework from various medical sector and political stakeholders.

The framework has a definition for rare disease in SA, namely a condition affecting one in 2000 people or fewer. It also recommends including rare diseases in the NHI benefit package. The NHI bill also includes a Benefits Advisory Committee, which will determine what diseases get coverage,

However, Dr Nicolas Crisp, Acting Director General for Health, said that the NHI would not ring-fence funding. As medical insurance will be done away with, it will be crucial to secure funding for those extremely expensive drugs unaffordable to the private sector.

Source: Spotlight

Study Highlights Role of Sex Hormones in Behavioural Development

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A new study shows that sex hormones are important for developing gender role behaviours in boys, such as active play.

In laboratory animals, sex differences in behaviour arise from different hormone levels produced by males and females influence patterns of gene expression in the developing brain. However, the origins of sex differences in human behaviour are not as well understood.

“In the lab, you can do experiments on how these hormones affect animal brains and perform other experimental manipulations. We can’t do those things to people, so we looked to a natural experiment,” explained study leader David Puts, associate professor of anthropology.

Prof Puts and his collaborators made use of a natural experiment called isolated GnRH deficiency (IGD), a rare endocrine disorder. Individuals with IGD lack sex hormones from the second trimester of development right through until they begin hormone replacement therapy to induce puberty. However, as the external genitals develop earlier, during the first trimester, people with IGD are clearly male or female at birth, and are raised according to their sex. 

IGD therefore presents the chance to study the behaviour of those raised as boys but exposed to low testicular hormones, or raised as girls but exposed to low ovarian hormones.

The researchers compared 97 individuals with IGD (a small number due to its rarity) to 1665 individuals with typical hormonal development. Differences in behaviour were investigated; boys being encouraged toward active play, girls pushed to more passive pursuits. The researchers asked subjects to recall behaviours they had as children.

“We asked them, ‘When you read a book, were you the male or female in the story?’, ‘Where your friends boys or girls?’, ‘Did you play with dolls or trucks?’,” said Talia N Shirazi, doctoral recipient in anthropology now working in the reproductive health industry.

These childhood gender role behaviours are among the largest differences in behaviour between sexes, Prof Puts said. Typically, males will say they were the male character, played with other boys and preferred trucks, while females will say they were the female character, played with other girls and preferred dolls.

However, males with IGD reported more gender non-conforming in this regard. The researchers found in that men with IGD recalled a higher level of childhood gender non-conformity than typical men, while women with IGD did not differ from typical women in childhood gender conformity.

‘”We don’t see this effect in the women with IGD,” said Shirazi, indicating that low levels of ovarian hormones does not significantly impact childhood gender role behaviours.

“Our results suggest that in humans, androgens, such as testosterone produced by the testes, influence male brain development directly as they do in other mammals, rather than only indirectly by influencing external appearance and consequently gender socialisation,” said Prof Puts. “Both the direct influence of androgens on the developing brain and gender socialisation probably play important roles in producing sex differences in childhood behaviour.”

Prof Puts and Shirazi agree that despite their modest sample of participants with IGD, they are encouraged that the results were very similar in subjects who came from a clinical setting and those recruited from support groups.

“It would be nice to be able to identify people with IGD when they are younger, before they reach what should be puberty,” said Shirazi. “We need to focus on recruitment for our studies because there is a lot that can be learned about the cause of gender behaviours.”

Source: Penn State

Common Chemical in Medical Products Linked to Breast Cancer

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Researchers in Japan have found that widely used chemicals called photoinitiators cause breast tumours to accelerate in mice. 

Photoinitiators, which release reactive molecules in response to UV radiation,  are used in a wide range of products, including plastics, paints, inks, and adhesives. Photoinitiators are present in common objects as well as in medical products and instruments such as dental fillers and containers.

Recent studies have demonstrated several health hazards associated with photoinitiators, raising safety concerns. In particular, the presence of these compounds in clinical instruments, routinely used for treating high-risk individuals such as cancer patients, has become a major cause for concern. Previous research has shown that three photoinitiators commonly found in plastics and paints 1-HCHPK, MBB, and MTMP show oestrogen-like effects on cultured breast cancer cells, increasing their proliferation. Found in marketed injection solutions, the clear link between oestrogen activity and breast cancer made determining their effect a priority.

In a study published in Current Research in Toxicology, lead researcher Dr Yoichi Kawasaki and Prof Toshiaki Sendo from Okayama University examined how exposure to 1-HCHPK, MBB, and MTMP affected the growth of transplanted breast cancer tumours in mice. They found that all three compounds caused a faster increase in the growth of breast tumors, within 13 weeks of treatment. “This study extends our previous findings and shows that in addition to promoting the proliferation of breast cancer cells in culture, these photoinitiators also increase the growth of breast tumours in live animals. This implies that they could also potentially hasten disease progression in breast cancer patients,” explained Dr Kawasaki.    

The study results show that 1-HCHPK, MBB, and MTMP have oestrogen-like activity and could thus act as hormonal disruptions. Given oestrogen’s role in regulating reproductive function in both men and women, such disruptions could affect not only patients with breast cancer, but also healthy individuals. While the researchers intend to explore the effects of photoinitiators on reproduction in future research, the present study informs breast cancer management, as well as making urgent call-to-action to eliminate toxic materials from medical equipment.

“Photoinitiators have helped us improve the quality of several commonly used products. But it is time we reconsider whether their benefits outweigh their risks, and our findings are an important milestone in encouraging this conversation. We hope that it will prompt more intensive research and stricter regulations on what materials can be adopted for commonly used products, especially those with medical applications,” said Dr Kawasaki.

Source: EurekAlert!

New Effort to Improve Diversity in Clinical Trials

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Columbia University and Pfizer Inc. have established the Columbia-Pfizer Clinical Trials Diversity Initiative, which aims to reduce health disparities by increasing the number of minorities in clinical trials and making clinical researchers more diverse.

In the United States, 12% of the population is Black and 18% is Hispanic or Latino but in 2020, only 8% were Black and 11% were Hispanic among the 32 000 patients who participated in clinical trials that led to FDA approval of new drugs. For example, a review of clinical trials between 1999 and 2015 for cystic fibrosis only had a representation of 2.0% for Latinos, 1.0% for Black individuals, and 0.1% for Asians.

“People of different ethnicities can have different responses to the same medicine or treatment, so a lack of diversity among clinical trial participants means doctors cannot know if the treatment will be effective in all the patients they treat,” said Anil K Rustgi, MD, Interim Executive Vice President and Dean of the Faculties of Health Sciences and Medicine at Columbia University and director of the Herbert Irving Comprehensive Cancer Center. “Increasing diversity in trials will improve the treatment of patients from underrepresented groups and is a moral imperative as well as a fundamental medical issue.”

Rod MacKenzie, PhD, Executive Vice President and Chief Development Officer at Pfizer, said, “Diversity of representation in clinical trials is a matter of equity, which is a core Pfizer value. We are deeply committed to ensuring our clinical trials reflect the diversity of the communities like New York in which they are conducted. We look forward to working with Columbia University both to offer any willing individual, regardless of background, the opportunity to participate in and contribute to clinical research, and to expand the roster of diverse clinical researchers who are helping us conduct studies.”

Pfizer will provide a three-year, $10 million grant to Columbia to help establish and expand the Initiative, which will improve the diversity of participants in clinical trials by looking at the barriers that prevent participation by marginalised individuals. The Initiative will expand Columbia’s Community Health Workers Program network to connect with underserved populations and create culturally sensitive engagement tools. The efforts will include researching new ways to increase the accessibility of clinical trials through telemedicine, wearable technology, and home visits.

The Initiative also aims to improve diversity among clinical research faculty and staff. Columbia will help build an additional pipeline of diverse clinical investigators through a new National Diversity Clinical Trials Leadership Program to increase the number of faculty and staff from underrepresented groups as well.

“A diverse research staff not only helps to improve trust in clinical trials among participants from underserved groups but improves the entire clinical trial enterprise by bringing different questions, experience, and perspective to the table,” Dr Rustgi said.

Source: Columbia University Irving Medical Center

Glasses Boosts Academic Performance for Students Who Need Them

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Students receiving eyeglasses through a school-based initiative scored higher on reading and math tests, found in the largest clinical study of the impact of glasses on education ever conducted in the US. Students struggling the most academically showed the greatest improvement.

The study by Johns Hopkins researchers from the Wilmer Eye Institute and School of Education is published in JAMA Ophthalmology.

“We rigorously demonstrated that giving kids the glasses they need helps them succeed in school,” said senior author Megan Collins, a paediatric ophthalmologist at the Wilmer Eye Institute. “This collaborative project with Johns Hopkins, Baltimore City and its partners has major implications for advancing health and educational equity all across the country.”

The team studied students who received eye examinations and glasses through the Vision for Baltimore program. The effort was launched in 2016 after an acute need for vision care among the city’s public school students was identified: as many as 15 000 of the city’s 60 000 pre-K (age 2 to 4) through 8th-grade (age 13 to 14) students likely needed glasses though many were unaware or were unable to get them.

Over five years, Vision for Baltimore has tested the vision of more than 64 000 students and distributed more than 8000 pairs of glasses. The Johns Hopkins study represents the most robust work thus far evaluating whether having glasses affects a child’s performance in school.

The three-year randomised clinical trial, conducted from 2016 to 2019, analysed the performance of 2304 students in grades 3 to 7 who received screenings, eye examinations and eyeglasses from Vision for Baltimore. The team looked at their scores on standardised reading and math tests, measuring both 1-year and 2-year impact.

After one year, reading scores increased significantly for students who got glasses, compared to those getting glasses later. There was also significant improvement in maths for students in primary grades.

There were particularly striking improvements for girls, special education students, and students who had been among the lowest performing.

Megan Collins, senior author said, “The glasses offered the biggest benefit to the very kids who needed it the most – the ones who were really struggling in school.”

The gains were about the same as two to four months of extra education compared to students with glasses, said lead author Amanda J Neitzel, deputy director of evidence research at the Johns Hopkins Center for Research and Reform in Education. For students performing in the lowest quartile and students in special education, wearing glasses equated to four to six months of additional learning.

“This is how you close gaps,” Neitzel said.

However, the academic improvements seen after one year were not sustained over two years. Researchers suspect this could be a result of students starting to wear their glasses less, perhaps from loss or breakage.

To keep up the academic achievement boost, the researchers recommend that school-based vision initiatives should also try to ensure children are wearing the glasses and to replace them if needed.

Source: Johns Hopkins University