Diabetic retinopathy among Brazilian Xavante Indians

Prevalence and incidence of diabetic retinopathy in patients with diabetes of Latin America and the Caribbean: A systematic review and meta-analysis

OBJECTIVES

This systematic review aimed to assess the prevalence and incidence of diabetic retinopathy in patients with diabetes of Latin America and the Caribbean.

METHODS

We searched Web of Science (WoS)/Core Collection, WoS/MEDLINE, WoS/Scielo, Scopus, PubMed/Medline and Embase databases until January 16, 2023. We meta-analyzed prevalences according to type 1 diabetes mellitus (T1DM) and type 2 diabetes mellitus (T2DM).

RESULTS

Forty-three prevalence studies (47 585 participants) and one incidence study (436 participants) were included. The overall prevalence of retinopathy in patients with T1DM was 40.6% (95% CI: 34.7 to 46.6; I2: 92.1%) and in T2DM was 37.3% (95% CI: 31.0 to 43.8; I2: 97.7), but the evidence is very uncertain (very low certainty of evidence). In meta-regression, we found that age (T1DM) and time in diabetes (T2DM) were factors associated with the prevalence. On the other hand, one study found a cumulative incidence of diabetic retinopathy of 39.6% at 9 years of follow-up.

CONCLUSIONS

Two out of five patients with T1DM or T2DM may present diabetic retinopathy in Latin America and the Caribbean, but the evidence is very uncertain. This is a major public health problem, and policies and strategies for early detection and opportunely treatment should be proposed.

Prevalence of diabetic retinopathy in Brazil: a systematic review with meta-analysis

AIMS

To evaluate the prevalence of diabetic retinopathy (DR) in Brazilian adults with diabetes mellitus via a systematic review with meta-analysis.

METHODS

A systematic review using PubMed, EMBASE, and Lilacs was conducted, searching for studies published up to February 2022. Random effect meta-analysis was performed to estimate the DR prevalence.

RESULTS

We included 72 studies (n = 29,527 individuals). Among individuals with diabetes in Brazil, DR prevalence was 36.28% (95% CI 32.66-39.97, I2 98%). Diabetic retinopathy prevalence was highest in patients with longer duration of diabetes and in patients from Southern Brazil.

CONCLUSION

This review shows a similar prevalence of DR as compared to other low- and middle-income countries. However, the high heterogeneity observed-expected in systematic reviews of prevalence-raises concerns about the interpretation of these results, suggesting the need for multicenter studies with representative samples and standardized methodology.

Genetic determinants and absence of breast cancer in Xavante Indians in Sangradouro Reserve, Brazil

Genetic compositions of distinct human populations are different. How genomic variants influence many common and rare genetic diseases is always of great medical and anthropological interest, and understanding of genetic architectures of population groups in relation to diseases can advance our knowledge of medicine. Here, we have studied the genomic architecture of a group of Xavante Indians, an indigenous population in Brazil, and compared them with normal populations from the 1000 Genomes Projects. Principal component analysis (PCA) indicates that the Xavante Indians are genetically distinctive when compared to other ethnic groups. No incidence of breast cancer cases has ever been reported in the population, and polygenic risk analysis indicates extremely low breast cancer risk in this population when compared with germline TCGA (The Cancer Genome Atlas) breast cancer normal control samples. Low germinal mutation burden among this population is also observed. Our findings will help to deepen the understanding of breast cancer and might also provide new approaches to study the disease.

The feasibility of smartphone based retinal photography for diabetic retinopathy screening among Brazilian Xavante Indians

AIMS

To evaluate the feasibility of smartphone based retinal photography for diabetic retinopathy (DR) screening among Brazilian Xavante Indians and the yield of retinal images.

METHODS

A non-probabilistic cluster sample of 170 individuals with and without diabetes was enrolled for ocular examination with a portable retinal camera during DR screening at two Xavante Reservations. Due to operational conditions and to optimize the field work, only the larger Xavante villages were included. Images were obtained after pupil dilation; image analysis included assessment of quality, presence of media opacities and diabetic retinopathy grading whenever possible for individuals with diabetes.

RESULTS

A total of 157 individuals underwent the complete ocular imaging protocol, 95 with diabetes (60.5%). Among those with diabetes, 23 (24.2%) could not have DR graded because of media opacities. For those with gradable images, the frequency of DR was 22.2%; sight-threatening DR was present in 9.7%. The main causes for ungradable images were cataracts and asteroid hyalosis.

CONCLUSIONS

The presence of DR was higher than in previous studies, calling attention for its prevention in this vulnerable population. The screening model with a smartphone-based portable retinal camera is feasible and could increase screening coverage if associated with telemedicine.

Serum SCUBE-1 levels in patients with diabetic retinopathy

PURPOSE

Signal peptide-CUB-Epidermal growth factor-like domain-containing protein 1 (SCUBE-1) is a protein expressed on the cell surface of endothelial cells and platelets. We aimed to determine the alterations in SCUBE-1 levels in patients at different stages of diabetic retinopathy (DR).

MATERIALS AND METHODS

Participants were grouped into 4 regarding the presence and stage of diabetic retinopathy as follows: control group (n 32), patients without DR (n 39), patients with background DR (n 42) and patients with proliferative DR (n 55). Age, gender, duration of diabetes, fasting blood glucose levels, serum hemoglobin A1c (HbA1c), SCUBE-1 and malondialdehyde (MDA) levels of the patients were recorded. Central macular thickness and central macular volume were recorded and compared between groups.

RESULTS

Totally 136 patients with diabetes mellitus and 32 control cases were included in the study. There is a significant increase in SCUBE-1 and MDA levels with an advance in DR. In correlation analysis, there was only a significant correlation present between serum SCUBE-1 and MDA levels (p 0.001) but not with other parameters.

CONCLUSION

For the first time in literature, we determined a significant increase in SCUBE-1 levels in patients with DR. Moreover, with an advance in DR, SCUBE-1 levels were also increasing.