Diabetes and Adverse Outcomes in a First Nations Population: Associations With Healthcare Access, and Socioeconomic and Geographical Factors

doi:10.1016/S1499-2671(07)13009-4

Canadian Journal of Diabetes

Volume 31, Issue 3, 2007, Pages 223-232

https://doi.org/10.1016/S1499-2671(07)13009-4 Get rights and content

ABSTRACT

OBJECTIVE

For Aboriginal on-reserve First Nations populations of Manitoba, Canada, this study explores (i) diabetes and amputation patterns; and (ii) their ecologic associations with geography, income and access to healthcare.

RESEARCH DESIGN AND METHODS

De-identified administrative claims data in the Population Health Research Data Repository were linked to federal Status Verification System files for 1995 to 1999 (n = 48 036 First Nations; 1 054 422 other Manitobans). Directly standardized rates were determined for ages 20 to 79 using International Classification of Diseases, 9th Revision, Clinical Modification codings: (i) treatment prevalence of diabetes, using physician and hospital billing claims with diagnosis 250; (ii) lower limb amputation with diabetes comorbidity (diagnosis 250) using hospitalization procedure codes 84.40 and 84.45 to 84.48. Ecologic correlations at the tribal council level, consisting of 9 First Nations on-reserve groupings, examined associations of diabetes indicators, average household income (1996 Statistics Canada census), ambulatory consult rates and geography (north vs. south).

RESULTS

Comparing First Nations with other Manitobans, rates of diabetes (203 vs. 45 per thousand) and amputation (3.39 vs. 0.19 per thousand) were higher. For on-reserve First Nations, diabetes varied by tribal council (149 to 249 per thousand) and was associated with income (r = —0.82, p = 0.007) and geography (north 186.8, south 227.9, p < 0.04), but not consult rates. First Nations amputation rates varied by tribal council (1.19 to 6.16 per thousand) and were associated with consult rates (r = —0.73, p = 0.025), but not with income or geography.

CONCLUSION

Among First Nations, diabetes prevalence is associated with socioeconomic (income) and geographic gradients, whereas the adverse outcome of amputation is associated with healthcare access (consult rates). Even within universally insured industrialized countries, First Nations barriers to healthcare must be addressed.

RÉSUMÉ

OBJECTIF

Cette étude, menée chez des Autochtones des Premières nations qui habitent dans une resérve du Manitoba, au Canada, explore (i) le diabète et l'amputation et (ii) leur association écologique a la géographie, au revenu et a l'accès aux soins de santé.

PLAN ET MÉTHODES

On a fait un rapprochement entre les données sur les demandes administratives dépersonnalisées tirées du registre Population Health Research Data Repository du Manitoba et celles du registre fédéral des Premiéres nations Status Verification System des annees 1995 à 1999 (n = 48 036 Autochtones; 1 054 422 autres Manitobains). Des taux directement normalisés ont été déterminés pour les personnes de 20 à 79 ans à partir des codes de la Classification internationale des mala-dies (International Classification of Diseases, 9th Revision, Clinical Modification [ICD-9-CM]) : (i) traitement et prévalence du diabéte à partir des factures des medecins et des hôpitaux et du diagnostic 250; (ii) amputation d'un membre inférieur chez une personne diabétique (diagnostic 250) à partir des codes d'intervention des hopitaux 84.40 et 84.45 a 84.48. Les corrélations écologiques au niveau du Conseil tribal, composé de neuf groupes d'Autochtones des Premiéres nations, ont porté sur les liens entre les indicateurs du diabète, le revenu familial moyen (recensement de 1996 de Statistique Canada), les taux de consultation ambulatoire et la géographie (nord vs sud).

RÉSULTATS

La comparaison entre les Autochtones des Prèmieres nations et les autres Manitobains a révélé que la fréquence du diabète (203 par rapport à 45 pour 1000) et des amputations (3,39par rapport à 0,19 pour 1000) était plus éleves chez les Autochtones. Chez les Autochtones habitant dans une reserve, la fréquence du diabète variait d'un Conseil tribal a l'autre (149 à 249 pour 1000) et était associée au revenu (r = -0,82; p = 0,007) et à la géographie (nord : 186,8; sud : 227,9; p < 0,04), mais ne variait pas en fonction des taux de consultation. Les taux d'amputation chez les Autochtones variaient d'un Conseil tribal à l'autre (1,19 à 6,16 pour 1000) et étaient associés aux taux de consultation (r = -0,73; p = 0,025), mais non au revenu ni à la géographie.

CONCLUSION

Chez les Autochtones des Premières nations, la prévalence du diabète est associée à des facteurs socio-économiques (revenu) et géographiques, tandis que les amputations sont associées au manque d'accès aux soins de santé (taux de consultation). Même dans les pays industrialisés ou l'assurance est universelle, les problèmes d'accès aux soins de santé des Autochtones doivent être réglés.

Section snippets

INTRODUCTION

Inequalities in health status of Aboriginal peoples are well documented throughout the world (1) and are also mirrored in population-based comparisons in the province of Manitoba, Canada. Manitoba First Nations people have a life expectancy that is 8 years lower than other Manitobans, both for males (68.4 vs. 76.1 years) and females (73.2 vs. 81.4 years) (2). One of the major health concerns of Canadian First Nations people is type 2 diabetes (also known as adult-onset or noninsulin-dependent

Geographical regions and population counts

In this study, diabetes-related indicators are compared by the 9 tribal council areas (see Figure 1 for location and population size—7 political tribal council geographical areas, plus 2 virtual tribal council areas: "Independent First Nations North" (a contingent geographical area of 3 northern independent/unaffiliated First Nations band communities); and "Independent First Nations South" (a non-contingent virtual "area" of 5 First Nations communities found within other southern tribal council

Diabetes prevalence

The overall age- and sex-adjusted diabetes prevalence for Manitoba Registered First Nations people living on-reserve was 203 per thousand (i.e. 20.3% of the population aged 20 to 79). The crude, unadjusted rate was 150 per thousand, translating to 3582 people with diabetes out of a total Registered First Nations population of 23 844. Age- and sexadjusted diabetes prevalence varied from 149 per thousand in Keewatin Tribal Council to 249 per thousand in the southern Dakota Ojibway Tribal Council (

DISCUSSION

This study had 2 objectives: namely, to determine prevalence of diabetes and rates of lower limb amputation with diabetes comorbidity, and to determine associations between these 2 outcomes and various determinants of health and healthcare access. For the second objective, the limitations of using ecologic data must be underscored. Aggregate group rates, not individual outcomes, have been used to calculate the hypothesized associations, and therefore extreme caution must be exercised in making

AUTHOR CONTRIBUTIONS

PJM was principal investigator, overseeing the conceptualization and design of the study, data acquisition, and analysis and interpretation of the data, as well as being the primary author of the manuscript. JO contributed to the acquisition of data, and MM contributed to the writing of the draft article. BM, JO and MM contributed to the analysis and interpretation of data and to the revision of the draft article for important intellectual content. All authors have seen and approved the final

AUTHOR DISCLOSURES

No dualities of interest declared.

ACKNOWLEDGMENTS

This work was supported as part of a project on First Nations health, one of several projects undertaken each year under contract to Manitoba Health by the Manitoba Centre for Health Policy, a unit of the University of Manitoba's Department of Community Health Sciences. The working group for the study was the Health Information Research Committee of the Assembly of Manitoba Chiefs from 1999 to 2002, comprised of the health directors of each tribal council and independent First Nations

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Diabetes and Adverse Outcomes in a First Nations Population: Associations With Healthcare Access, and Socioeconomic and Geographical Factors

ABSTRACT

OBJECTIVE

RESEARCH DESIGN AND METHODS

RESULTS

CONCLUSION

RÉSUMÉ

OBJECTIF

PLAN ET MÉTHODES

RÉSULTATS

CONCLUSION

Section snippets

INTRODUCTION

Geographical regions and population counts

Diabetes prevalence

DISCUSSION

AUTHOR CONTRIBUTIONS

AUTHOR DISCLOSURES

ACKNOWLEDGMENTS

Lancet.

J Vasc Surg.

Soc Sci Med.

Arch Phys Med Rehabil.

Health Policy.

Mortality comparisons of First Nations to all other Manitobans: a provincial populationbased look at health inequalities by region and gender

Can J Public Health.

Predicting which patients will develop chronic critical leg ischemia

Semin Vasc Surg.

Diabetes-related lower-limb amputations in Australia

Med J Aust.

Risk factors for development of critical limb ischemia — a survey of diabetic vs. nondiabetic population

Prilozi

The relationship between provider coordination and diabetes-related foot outcomes

Diabetes Care.

Diabetes in Canada

A Statistical Profile on the Health of First Nations in Canada for theYear 2000

NDSS Diabetes Data, 2004

Complications of type 2 diabetes among Aboriginal Canadians: prevalence and associated risk factors

Diabetes Care.

Time trends and geographical disparities in acute complications of diabetes in Ontario

Canada. Diabetes Care.

Diabetes: A Manitoba Strategy

Type 2 diabetes mellitus in Canada's First Nations: status of an epidemic in progress

CMAJ.

The epidemiology of diabetes in the Manitoba-Registered First Nation population: current patterns and trends

Diabetes Care.