Cardiovascular disease risk profile and microvascular complications of diabetes: comparison of Indigenous cohorts with diabetes in Australia and Canada

Diabetic foot complications among Indigenous peoples in Canada: a scoping review through the PROGRESS-PLUS equity lens

Introduction

Indigenous peoples in Canada face a disproportionate burden of diabetes-related foot complications (DRFC), such as foot ulcers, lower extremity amputations (LEA), and peripheral arterial disease. This scoping review aimed to provide a comprehensive understanding of DRFC among First Nations, Métis, and Inuit peoples in Canada, incorporating an equity lens.

Methods

A scoping review was conducted based on Arksey and O'Malley refined by the Joanna Briggs Institute. The PROGRESS-Plus framework was utilized to extract data and incorporate an equity lens. A critical appraisal was performed, and Indigenous stakeholders were consulted for feedback. We identified the incorporation of patient-oriented/centered research (POR).

Results

Of 5,323 records identified, 40 studies were included in the review. The majority of studies focused on First Nations (92%), while representation of the Inuit population was very limited populations (< 3% of studies). LEA was the most studied outcome (76%). Age, gender, ethnicity, and place of residence were the most commonly included variables. Patient-oriented/centered research was mainly included in recent studies (16%). The overall quality of the studies was average. Data synthesis showed a high burden of DRFC among Indigenous populations compared to non-Indigenous populations. Indigenous identity and rural/remote communities were associated with the worse outcomes, particularly major LEA.

Discussion

This study provides a comprehensive understanding of DRFC in Indigenous peoples in Canada of published studies in database. It not only incorporates an equity lens and patient-oriented/centered research but also demonstrates that we need to change our approach. More data is needed to fully understand the burden of DRFC among Indigenous peoples, particularly in the Northern region in Canada where no data are previously available. Western research methods are insufficient to understand the unique situation of Indigenous peoples and it is essential to promote culturally safe and quality healthcare.

Conclusion

Efforts have been made to manage DRFC, but continued attention and support are necessary to address this population's needs and ensure equitable prevention, access and care that embraces their ways of knowing, being and acting.

Systematic review registration

Open Science Framework https://osf.io/j9pu7, identifier j9pu7.

Indigenous Eye Health in the Americas: The Burden of Vision Impairment and Ocular Diseases

Review of the burden of vision impairment and blindness and ocular disease occurrence in Indigenous Peoples of the Americas. We systematically reviewed findings of the frequency of vision impairment and blindness and/or frequency of ocular findings in Indigenous groups. The database search yielded 2829 citations, of which 2747 were excluded. We screened the full texts of 82 records for relevance and excluded 16. The remaining 66 articles were examined thoroughly, and 25 presented sufficient data to be included. Another 7 articles derived from references were included, summing a total of 32 studies selected. When considering adults over 40 years old, the highest frequencies of vision impairment and blindness in Indigenous Peoples varied from 11.1% in high-income North America to 28.5% in tropical Latin America, whose rates are considerably higher than those in the general population. Most of the ocular diseases reported were preventable and/or treatable, so blindness prevention programs should focus on accessibility to eye examinations, cataract surgeries, control of infectious diseases, and spectacles distribution. Finally, we recommend actions in six areas of attention towards improving the eye health in Indigenous Peoples: access and integration of eye services with primary care; telemedicine; customized propaedeutics; education on eye health; and quality of data.

Breast cancer in Indigenous women living in Canada: a scoping review protocol

OBJECTIVE

The objective of this review is to describe and synthesize the current state of knowledge pertaining to breast cancer in Indigenous women living in Canada. We will examine the continuum of breast cancer care in this population, including breast cancer screening, diagnosis, treatment, and surveillance.

INTRODUCTION

Breast cancer in Indigenous women is an evolving health care concern in Canada, with mounting evidence suggesting that these women present at later stages, and have poorer survival rates compared with the general population. A comprehensive overview of the state of knowledge of breast cancer in this population is required.

INCLUSION CRITERIA

The population of interest will include Indigenous women living in Canada aged 18 years or older who have been screened or require screening for breast cancer, or who have been diagnosed with breast cancer. "Indigenous" will include women who identify as First Nations, Métis, or Inuit. Eligible sources must report on breast cancer risk factors, tumor characteristics, health systems access, screening, diagnosis, treatment, surveillance, or breast cancer outcomes. We will include analytic studies, surveys, case series, reviews, meta-analyses, and gray literature.

METHODS

We will conduct a search of five health sciences databases for relevant studies published in English or French from database inception onward. We will utilize dual independent screening for titles, abstracts, and full-text articles, and will utilize a similar method for gray literature sources. Data will be synthesized using a narrative approach, and outcomes of interest will be compared with data from the general breast cancer population.

REGISTRATION

Open Science Framework https://osf.io/xkde5.

Feasibility of once weekly exenatide-LAR and enhanced diabetes care in Indigenous Australians with type 2 diabetes. (Long-acting-Once-Weekly-Exenatide laR-SUGAR, "Lower SUGAR" study)

AIMS

To assess the feasibility and metabolic effects of once weekly supervised injection of exenatide-LAR in addition to standard care in Indigenous Australians with type 2 diabetes.

METHODS

Two communities in Central Australia with longstanding specialist clinical outreach services were allocated by random coin toss to receive once-weekly exenatide-LAR injection with weekly nurse review and adjustment of medication for 20 weeks (community with exenatide-LAR) or to weekly nurse review in addition to standard care over 20 weeks (community without exenatide-LAR). The primary outcome was the feasibility of the intensive diabetes management model of care with and without weekly supervised exenatide-LAR. Secondary outcomes included change in HbA1c.

RESULTS

13 participants from community with exenatide-LAR and 9 participants from the community without exenatide-LAR were analysed. 85% of individuals in the community with exenatide-LAR and 67% in the community without exenatide-LAR attended more than half of clinic visits. Median difference in the change in HbA1c from baseline to final visit, adjusted for baseline HbA1c, between the community with exenatide-LAR and the community without exenatide-LAR was -3.1%, 95% CI (-5.80%, -0.38%; p = 0.03).

CONCLUSIONS

Weekly exenatide-LAR combined with weekly nurse review demonstrated greater improvements in HbA1c, highlighting its potential for use in remote communities. This article is protected by copyright. All rights reserved.

Differences in retinopathy prevalence and progression between Anglo-Celt and Aboriginal Australians: the Fremantle Diabetes Study Phase II

BACKGROUND

Indigenous populations have higher rates of diabetes and diabetic complications, yet there is a paucity of contemporary data on diabetic retinopathy (DR) prevalence and incidence in urban dwelling Aboriginal Australians.

AIMS

The aim of the study was to compare the prevalence of DR and incidence of new or worsening DR between Aboriginal Australians and Anglo-Celts with Type 2 diabetes.

METHODS

Participants from the community-based Fremantle Diabetes Study Phase II (817 Anglo-Celts, 94 Aboriginal people) recruited between 2008 and 2011 underwent fundus photography at baseline and biennial reviews. The prevalence of any DR and moderate non-proliferative DR (NPDR), and the incidence of new or worsening DR were ascertained using baseline and 4-year follow-up data.

RESULTS

Compared with Anglo-Celts, the Aboriginal participants had a higher prevalence of any DR (33.0% vs 52.1%) and moderate NPDR or worse (5.1% vs 24.4%), and new or worsening DR during follow up (6.7% vs 23.5%). The unadjusted odds ratios (95% confidence interval) of any DR and moderate NPDR at baseline were 2.21 (1.43, 3.39) and 5.98 (3.40, 10.50), respectively, and of new or worsening DR 4.32 (1.33, 13.98). In adjusted models, Aboriginal ethnicity was only associated with the prevalence of moderate NPDR or worse (5.58 (2.44, 12.76)).

CONCLUSIONS

Aboriginal participants had a higher prevalence of DR and new or worsening DR, reflecting conventional risk factors including suboptimal glycaemic control. Their significantly higher odds of moderate NPDR or worse in adjusted models suggest ethnic-specific determinants of DR severity. These findings highlight the need for equitable, culturally appropriate diabetes/ophthalmic care.

Epidemiologic features of medical emergencies in remote First Nations in northern Ontario: a cross-sectional descriptive study using air ambulance transport data

BACKGROUND

For about 25 000 Ontarians living in remote northern First Nations communities, seeing a doctor in an emergency department requires flying in an airplane or helicopter. This study describes the demographic and epidemiologic characteristics of patients transported from these communities to access hospital-based emergency medical care.

METHODS

In this cross-sectional descriptive study, we examined primary medical data on patient transportation from Ornge, the provincial medical air ambulance service provider, for 26 remote Nishnawbe Aski Nation communities in northern Ontario from 2012 to 2016. We described these transports using univariate descriptive statistics.

RESULTS

Over the 5-year study period, 10 538 patients (mean 2107.6 per year) were transported by Ornge from the 26 communities. Transport incidence ranged from 9.2 to 9.5 per 100 on-reserve population per year. Women aged 65 years or more had the highest transport incidence (25.9 per 100). Girls aged 5-9 years had the lowest mean incidence (2.1 per 100). Gastrointestinal issues accounted for 13.3% of transfers. Neurologic issues, respiratory issues and trauma each accounted for about 11% of transfers, and cardiac issues for 9.6%. Patients with obstetric issues accounted for 7.6% of transfers per year, and toxicologic emergencies for 7.5%.

INTERPRETATION

This study provides the epidemiologic foundation to improve emergency care and emergency transport from remote First Nation communities in Ontario.

Opportunistic pathogens and large microbial diversity detected in source-to-distribution drinking water of three remote communities in Northern Australia

In the wet-dry tropics of Northern Australia, drinking water in remote communities is mostly sourced from bores accessing groundwater. Many aquifers contain naturally high levels of iron and some are shallow with surface water intrusion in the wet season. Therefore, environmental bacteria such as iron-cycling bacteria promoting biofilm formation in pipes or opportunistic pathogens can occur in these waters. An opportunistic pathogen endemic to northern Australia and Southeast Asia and emerging worldwide is Burkholderia pseudomallei. It causes the frequently fatal disease melioidosis in humans and animals. As we know very little about the microbial composition of drinking water in remote communities, this study aimed to provide a first snapshot of the microbiota and occurrence of opportunistic pathogens in bulk water and biofilms from the source and through the distribution system of three remote water supplies with varying iron levels. Using 16s-rRNA gene sequencing, we found that the geochemistry of the groundwater had a substantial impact on the untreated microbiota. Different iron-cycling bacteria reflected differences in redox status and nutrients. We cultured and sequenced B. pseudomallei from bores with elevated iron and from a multi-species biofilm which also contained iron-oxidizing Gallionella, nitrifying Nitrospira and amoebae. Gallionella are increasingly used in iron-removal filters in water supplies and more research is needed to examine these interactions. Similar to other opportunistic pathogens, B. pseudomallei occurred in water with low organic carbon levels and with low heterotrophic microbial growth. No B. pseudomallei were detected in treated water; however, abundant DNA of another opportunistic pathogen group, non-tuberculous mycobacteria was recovered from treated parts of one supply. Results from this study will inform future studies to ultimately improve management guidelines for water supplies in the wet-dry tropics.

Defining the gap: a systematic review of the difference in rates of diabetes-related foot complications in Aboriginal and Torres Strait Islander Australians and non-Indigenous Australians

BACKGROUND

The Aboriginal and Torres Strait Islander community has an increased risk of developing chronic illnesses including diabetes. Among people with diabetes, foot complications are common and make a significant contribution to the morbidity and mortality associated with this disease. The aim of this review was to systematically evaluate the literature comparing the rates of diabetes related foot complications in Aboriginal and Torres Strait Islander Australians to non-Indigenous Australians.

METHODS

MEDLINE, EMBASE, The Cochrane Library; PUBMED and CINAHL were searched from inception until August 2016. Inclusion criteria were: published cross-sectional or longitudinal studies reporting the prevalence of diabetes related foot complications in both a cohort of Aboriginal and Torres Strait Islander Australians and a cohort of one other Australian population of any age with diabetes. Risk of bias was assessed using the STROBE tool.

RESULTS

Eleven studies including a total of 157,892 participants were included. Studies were set in Queensland, the Northern Territory and Western Australia, primarily in rural and remote areas. Aboriginal and Torres Strait Islander Australians experienced substantially more diabetes related foot complications with the mean age up to 14 years younger than non-Indigenous Australians. Aboriginality was associated with increased risk of peripheral neuropathy, foot ulceration and amputation. In several studies, Aboriginal and Torres Strait Islander Australians accounted for the vast majority of diabetes related foot complications (up to 91%) while comprising only a small proportion of the regional population. Reporting quality as assessed with the STROBE tool showed underreporting of: methods, sample description and potential sources of bias. There are no data available for some Australian states and for specific types of diabetes related foot complications.

CONCLUSIONS

Aboriginal and Torres Strait Islander Australians have a 3-6 fold increased likelihood of experiencing a diabetes related foot complication compared to non-Indigenous Australians. Evidence-based, culturally appropriate screening and intervention programs and improved access to effective health care services are required to prevent a widening of the gap in diabetes related foot complications between Aboriginal and Torres Strait Islander and non-Indigenous Australians.

Residential Location and Kidney Transplant Outcomes in Indigenous Compared With Nonindigenous Australians

BACKGROUND

Indigenous Australians experience significantly worse graft and patient outcomes after kidney transplantation compared with nonindigenous Australians. It is unclear whether rural versus urban residential location might contribute to this.

METHODS

All adult patients from the Australia and New Zealand Dialysis and Transplant Registry who received a kidney transplant in Australia between January 1, 2000, and December 31, 2012, were investigated. Patients' residential location was classified as urban (major city + inner regional) or rural (outer regional - very remote) using the Australian Bureau of Statistics Remoteness Area Classification.

RESULTS

Of 7826 kidney transplant recipients, 271 (3%) were indigenous. Sixty-three percent of indigenous Australians lived in rural locations compared with 10% of nonindigenous Australians (P < 0.001). In adjusted analyses, the hazards ratio for graft loss for Indigenous compared with non-Indigenous race was 1.59 (95% confidence interval [95% CI], 1.01-2.50; P = 0.046). Residential location was not associated with graft survival. Both indigenous race and residential location influenced patient survival, with an adjusted hazards ratio for death of 1.94 (95% CI, 1.23-3.05; P = 0.004) comparing indigenous with nonindigenous and 1.26 (95% CI, 1.01-1.58; P = 0.043) comparing rural with urban recipients. Five-year graft and patient survivals were 70% (95% CI, 60%-78%) and 69% (95% CI, 61%-76%) in rural indigenous recipients compared with 91% (95% CI, 90%-92%) and 92% (95% CI, 91%-93%) in urban nonindigenous recipients.

CONCLUSIONS

Indigenous kidney transplant recipients experience worse patient and graft survival compared with nonindigenous recipients, whereas rural residential location is associated with patient but not graft survival. Of all groups, indigenous recipients residing in rural locations experienced the lowest 5-year graft and patient survivals.

Non-traumatic lower limb amputation in patients with end-stage renal failure on dialysis: an Australian perspective

BACKGROUND

End-stage renal failure (ESRF) and dialysis have been identified as a risk factor for lower limb amputations (LLAs). High rate of ESRF amongst the Australian population has been reported, however till date no study has been published identifying magnitude and risk factors of LLA in subjects on renal dialysis.

OBJECTIVE

The study aims to document trends in the prevalence and identify risk factors of non-traumatic LLA in Australian patients on dialysis.

METHODS

A retrospective review of all patients (218) who attended the regional dialysis center between 1st January 2009 and 31st December 2013 was conducted. Demographic, clinical and biochemical data were analyzed.

RESULTS

We identified a high prevalence of 13.3% of LLAs amongst Australian patients with ESRF on dialysis at our center. The associated risk factors were the presence of diabetes (OR 1.67 [1.49-1.88] p < 0.001), history of foot ulceration (OR 81 [18.20-360.48] p < 0.001), peripheral arterial disease (OR 31.29 [9.02-108.56] p < 0.001), peripheral neuropathy (OR 31.29 [9.02-108.56] p < 0.001), foot deformity (OR 23.62 [5.82-95.93] p < 0.001), retinopathy (OR 6.08 [2.64-14.02] p < 0.001), dyslipidemia (OR 4.6 [1.05-20.05] p= 0.049) and indigenous background (OR 3.39 [1.38-8.33] p= 0.01). 75% of the amputees had aboriginal heritage. We also identified higher HbA1c and CRP levels as well as low serum albumin, hemoglobin and vitamin D levels to have a strong association with LLAs (p < 0.05).

CONCLUSION

There is high prevalence of LLAs amongst Australian indigenous patients with diabetes on dialysis in North Queensland. Other strongly associated risk factors include history of foot ulceration, foot deformity and peripheral neuropathy as well as high HbA1c levels and low serum albumin levels.

Health needs of older Aboriginal people in Taiwan: a community-based assessment using a multidimensional instrument

AIMS AND OBJECTIVES

To explore the health needs of older Aboriginal people, using a multidimensional instrument. The gender differences related to their health needs were also addressed.

BACKGROUND

Health status and life expectancy between Aborigines and non-Aborigines have been shown to differ. The investigation of the health needs of Aboriginal people is however scarce, particularly among the older adult population. There is a need to address unmet health needs and improve information on the health needs assessment of the older Aboriginal population.

DESIGN

A cross-sectional design was used.

METHODS

Aboriginal people aged 65 and over were randomly sampled to take part in the present study. A multidimensional instrument consisting of eight domains and three cross-domain categories was used to assess their health needs.

RESULTS

A group of older Aboriginal people was recruited (n = 90, mean age = 73·5). The top three identified needs were 'mental health and well-being', 'staying healthy' and 'social participation'. The female participants had statistically significant higher scores for the 'mental health and well-being', 'getting around' domains and in the 'risk of falls' than the male ones. A regression model demonstrated that the health need of 'looking after oneself' was associated with all cross-domain categories of health need, which are 'independence', 'risk of breakdown in care' and 'risk of falls'.

CONCLUSIONS

The present study has revealed major health needs among older Aboriginal people and found that older female Aborigines have more health needs than older male Aborigines. Further study to identify effective approaches to address these needs among this group is warranted.

RELEVANCE TO CLINICAL PRACTICE

The findings can be used to identify effective approaches to addressing health needs among older Aboriginal people with a consideration of gender. Only then can resources be allocated and prioritised in a culturally sensitive and gender-specific manner nationally and globally.

Australia's seizure divide - indigenous versus non-indigenous seizure hospitalization

Indigenous Australians suffer the highest mortality and morbidity rates of any ethnic minority in the developed world. To determine if the health outcome gulf between indigenous and non-indigenous Australians also applied to seizures, we conducted a retrospective analysis of seizure hospitalization (1998-2004) based on ethnicity (indigenous (I) and non-indigenous (NI)) for four Australian jurisdictions - Northern Territory (NT), Queensland (Qld), South Australia (SA), and Western Australia (WA). Total admissions were converted to age-standardized rates (ASR) and I/NI ASR ratios (I/NIRR) and compared across multiple variables. The summed admission (combined jurisdictions over six years) was 71,185 (I=11,593 and NI=59,592). Seizure hospitalization rate was always higher in the indigenous population (six-year I/NIRR - NT=5.6, Qld=4.0, SA=6.4, and WA=10.9; combined jurisdictions=5.6). Disparity was greatest for ages 40-64years (13.8) and 15-39years (7.0) and for indigenous males (7.4). As socioeconomic status rose, non-indigenous admission rates fell (ASR=1.7 to 1.1), yet indigenous admission rates rose (ASR=7.9 to 14.0). Indigenous emergency to elective admission ratios were higher (I=27 and NI=8), as were readmissions (1.5-2 fold), self-discharge separations (I=9.4% and NI=1.4%), bed days (I/NIRR=5.1), and admissions with an additional diagnosis (I/NIRR=3.3) or procedure (I/NIRR=3.4). Indigenous Australians maintained disproportionately high rates of emergency seizure hospitalization; from 1998 to 2004, the combined jurisdiction rate was more than five times the mean non-indigenous rate. Indigenous males aged 15-64years were overrepresented. Indigenous patients had lengthier admissions but higher self-discharge and readmission rates. The socioeconomic data raise the concern that social disadvantage restricts access to hospital-based seizure care for indigenous patients.

Total and high molecular weight adiponectin and ethnic-specific differences in adiposity and insulin resistance: a cross-sectional study

Background

Ethnic-specific differences in insulin resistance (IR) are well described but the underlying mechanisms are unknown. Adiponectin is an insulin sensitizing adipocytokine that circulates as multiple isoforms, with high molecular weight (HMW) adiponectin associated with greatest insulin sensitivity. The objective of this study is to determine if plasma total and HMW adiponectin concentrations underlie ethnic-specific differences in IR.

Methods

Healthy Canadian Aboriginal, Chinese, European, and South Asian adults (N = 634) were assessed for sociodemographics; lifestyle; fasting plasma insulin, glucose, and total and HMW adiponectin; and adiposity measures [BMI, waist circumference, waist-to-hip ratio, percent body fat, and subcutaneous and visceral adipose tissue (quantified by computed tomography)]. The homeostasis model assessment-insulin resistance (HOMA-IR) assessed IR.

Results

South Asians had the greatest HOMA-IR, followed by Aboriginals, Chinese, and Europeans (P < 0.001). Plasma total and HMW adiponectin concentrations were lower in Chinese and South Asians than Aboriginal and Europeans (P < 0.05). Total and HMW adiponectin were inversely associated with HOMA-IR (P < 0.001). Ethnicity modified the relationship between HMW adiponectin and HOMA-IR with stronger effects observed in Aboriginals (P = 0.001), Chinese (P = 0.002), and South Asians (P = 0.040) compared to Europeans. This was not observed for total adiponectin (P = 0.431). At mean total adiponectin concentrations South Asians had higher HOMA-IR than Europeans (P < 0.001).

Conclusions

For each given decrease in HMW adiponectin concentrations a greater increase in HOMA-IR is observed in Aboriginals, Chinese, and South Asians than Europeans. Ethnic-specific differences in HMW adiponectin may account for differences in IR.

Similarities and differences in cardiometabolic risk factors among remote Aboriginal Australian and Canadian cohorts

AIM

Indigenous populations of Australia and Canada experience disproportionately high rates of chronic disease. We hypothesized that despite the common outcome of increased diabetes prevalence, differences in cardiometabolic risk profile may exist between these populations.

METHODS

We compared community-based data on cardiometabolic risks in Aboriginal Australians (n=297 without, 45 with diabetes), and Aboriginal Canadians (n=409 without, 87 with diabetes).

RESULTS

Despite strikingly lower weight (62 vs 83 kg, p<0.0001) and body mass index (BMI, 22 vs 29 kg/m(2), p<0.0001), Aboriginal Australians without diabetes had similar waist-hip ratio (WHR, 0.91 vs 0.91, p=0.732), lower HDL-cholesterol (0.97 vs 1.25 mmol/L, p<0.0001) and higher HbA1c (5.4 vs 5.2%, p<0.0001) than Aboriginal Canadians without diabetes. Waist was the obesity measure most strongly related to diabetes or cardiometabolic risk in Australians while BMI performed similarly to other obesity measures only in Canadians. Multiple regression of HbA1c revealed age and fasting glucose as independent predictors in each study group, with the addition of WHR in Aboriginal Australians.

CONCLUSION

The notable finding was that waist or WHR are preferred obesity measures to appropriately reflect cardiometabolic risk in Aboriginal Australians, who although leaner by BMI criteria, displayed a similarly adverse risk profile to Aboriginal Canadians. Waist or WHR should be routinely included in clinical assessment in these high-risk populations.