Diabetes epidemic detected among Xavante indigenous community in Central Brazil

November 10, 2020

The Xavante, one of the indigenous communities most vulnerable to SARS-CoV-2 in Brazil, are suffering from an epidemic of diabetes, a "silent" disease considered a risk factor for severe COVID-19.

A group of researchers affiliated with the Federal University of São Paulo's Medical School (EPM-UNIFESP) and the University of São Paulo's Ribeirão Preto Medical School (FMRP-USP) examined the retinas of 157 individuals before the COVID-19 pandemic and found a high prevalence of type 2 diabetes and eye disorders caused by the disease.

The study was supported by São Paulo Research Foundation - FAPESP (https://bv.fapesp.br/en/auxilios/28693), and the results are published (https://www.sciencedirect.com/science/article/abs/pii/S0168822720306331) in Diabetes Research and Clinical Practice, the official journal of the International Diabetes Federation.

"Ninety-five of the 157 Xavante we examined [60.5%] were diagnosed with diabetes," Fernando Korn Malerbi (https://bv.fapesp.br/en/pesquisador/47115/fernando-korn-malerbi), a postdoctoral researcher in the Ophthalmology Department of EPM-UNIFESP and first author of the article published on the study.

According to Malerbi, diabetes can cause ocular problems such as retinopathy. Diabetic retinopathy develops when high blood sugar levels damage blood vessels in the retina, leading to vision loss if left untreated.

To diagnose cases of diabetic retinopathy and other possible eye disorders, the researchers examined members of the Xavante community on the Volta Grande and São Marcos Reservations in the state of Mato Grosso in Brazil's Center-West region. They used a smartphone-controlled retinal photography system developed by Phelcom Technologies (https://phelcom.com.br/en/company/) via a project (https://bv.fapesp.br/en/auxilios/105359) supported by FAPESP's Innovative Research in Small Business Program (PIPE (https://bv.fapesp.br/en/3/)).

Called the Eyer, the handheld retinograph is an optical device that produces precise images of the retina to detect back-of-the-eye (fundus) disease at a far lower cost than conventional methods. In addition, it has the advantage of being usable for remote diagnosis by an ophthalmologist via telemedicine.

The optical device is connected to a smartphone. It lights up and images the retina, and a specially written software application sends the images over the internet to Eyer Cloud, which stores and manages patient files.

In the absence of Wi-Fi or a 3G or 4G network, the images are stored in the smartphone and sent to the cloud when a broadband internet connection becomes available (read more at: agencia.fapesp.br/30784 (https://agencia.fapesp.br/portable-device-can-be-used-to-diagnose-eye-disease-remotely/30784/)).

Malerbi personally examined the Xavante volunteers and promptly gave them his diagnosis. "When retinal damage suggesting a risk of blindness was observed via the handheld retinograph, we informed the subjects via an interpreter and referred them to the local indigenous health service for follow-up and treatment," he said.

Of the 95 individuals with diabetes who underwent the complete ocular imaging protocol, 23 (24.2%) had ungradable images owing to cataract-caused media opacities that precluded evaluation of retinopathy in at least one eye.

Images from the remaining 72 subjects (75.8%) were good enough for diabetic retinopathy to be detected. The researchers found that 16 had the disease, and it was severe enough to be sight-threatening in seven.

"We proved that screening for diabetic retinopathy with a portable retinograph is feasible and economically viable because the technology is inexpensive and can be used in remote communities such as Indian reservations, where the population is usually dispersed in several villages," Malerbi said.

Deteriorating health

A previous study of eye problems among the Xavante reported diabetic retinopathy prevalence of 19.3% in the same locations. The higher level of prevalence found in this latest study may be due to the superior quality of the retinal camera images compared with the indirect ophthalmoscopy method used in the earlier study.

Another hypothesis is that the health of this indigenous population - one of the largest in Brazil, comprising some 17,000 Indians living on nine reservations - has deteriorated in the intervening years, the researchers surmised.

A previous study showed that 66.1% of 932 members of the Xavante community had metabolic syndrome, defined as a condition in which risk factors for cardiovascular disease and diabetes mellitus occur in the same individual.

For the researchers, the situation reflected changes in health profile and diet in recent decades, especially the consumption of industrialized foods and sedentary living (read more at: agencia.fapesp.br/22624 (https://agencia.fapesp.br/two-thirds-of-an-indigenous-community-have-metabolic-syndrome-and-are-obese/22624/)).

"The Xavante were traditionally hunter-gatherers but have become more sedentary. They've also changed their diet in recent decades, consuming new foodstuffs with high sugar content," Malerbi said.

Besides the Xavante, the researchers also examined the retinas of 33 Bororo - another community endangered by both COVID-19 and the bush fires that destroyed much of the Pantanal this year. Seven Bororo were found to have diabetes. One of these was diagnosed with severe diabetic retinopathy and referred to a health service for treatment.
-end-
About São Paulo Research Foundation (FAPESP)

The São Paulo Research Foundation (FAPESP) is a public institution with the mission of supporting scientific research in all fields of knowledge by awarding scholarships, fellowships and grants to investigators linked with higher education and research institutions in the State of São Paulo, Brazil. FAPESP is aware that the very best research can only be done by working with the best researchers internationally. Therefore, it has established partnerships with funding agencies, higher education, private companies, and research organizations in other countries known for the quality of their research and has been encouraging scientists funded by its grants to further develop their international collaboration. You can learn more about FAPESP at http://www.fapesp.br/en and visit FAPESP news agency at http://www.agencia.fapesp.br/en to keep updated with the latest scientific breakthroughs FAPESP helps achieve through its many programs, awards and research centers. You may also subscribe to FAPESP news agency at http://agencia.fapesp.br/subscribe.

Fundação de Amparo à Pesquisa do Estado de São Paulo

Related Diabetes Articles from Brightsurf:

New diabetes medication reduced heart event risk in those with diabetes and kidney disease
Sotagliflozin - a type of medication known as an SGLT2 inhibitor primarily prescribed for Type 2 diabetes - reduces the risk of adverse cardiovascular events for patients with diabetes and kidney disease.

Diabetes drug boosts survival in patients with type 2 diabetes and COVID-19 pneumonia
Sitagliptin, a drug to lower blood sugar in type 2 diabetes, also improves survival in diabetic patients hospitalized with COVID-19, suggests a multicenter observational study in Italy.

Making sense of diabetes
Throughout her 38-year nursing career, Laurel Despins has progressed from a bedside nurse to a clinical nurse specialist and has worked in medical, surgical and cardiac intensive care units.

Helping teens with type 1 diabetes improve diabetes control with MyDiaText
Adolescence is a difficult period of development, made more complex for those with Type 1 diabetes mellitus (T1DM).

Diabetes-in-a-dish model uncovers new insights into the cause of type 2 diabetes
Researchers have developed a novel 'disease-in-a-dish' model to study the basic molecular factors that lead to the development of type 2 diabetes, uncovering the potential existence of major signaling defects both inside and outside of the classical insulin signaling cascade, and providing new perspectives on the mechanisms behind insulin resistance in type 2 diabetes and possibly opportunities for the development of novel therapeutics for the disease.

Tele-diabetes to manage new-onset diabetes during COVID-19 pandemic
Two new case studies highlight the use of tele-diabetes to manage new-onset type 1 diabetes in an adult and an infant during the COVID-19 pandemic.

Genetic profile may predict type 2 diabetes risk among women with gestational diabetes
Women who go on to develop type 2 diabetes after having gestational, or pregnancy-related, diabetes are more likely to have particular genetic profiles, suggests an analysis by researchers at the National Institutes of Health and other institutions.

Maternal gestational diabetes linked to diabetes in children
Children and youth of mothers who had gestational diabetes during pregnancy are at increased risk of diabetes themselves, according to new research published in CMAJ (Canadian Medical Association Journal).

Two diabetes medications don't slow progression of type 2 diabetes in youth
In youth with impaired glucose tolerance or recent-onset type 2 diabetes, neither initial treatment with long-acting insulin followed by the drug metformin, nor metformin alone preserved the body's ability to make insulin, according to results published online June 25 in Diabetes Care.

People with diabetes visit the dentist less frequently despite link between diabetes, oral health
Adults with diabetes are less likely to visit the dentist than people with prediabetes or without diabetes, finds a new study led by researchers at NYU Rory Meyers College of Nursing and East Carolina University's Brody School of Medicine.

Read More: Diabetes News and Diabetes Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.