Health Reports
Acute care hospitalization of Aboriginal children and youth

by Anne Guèvremont, Gisèle Carrière, Evelyne Bougie and Dafna Kohen

Release date: July 19, 2017

Research has shown less favourable health outcomes for Aboriginal children and youth compared with their non-Aboriginal contemporaries.Note 1Note 2Note 3Note 4Note 5Note 6 Analyses of provincial administrative data have also found higher rates of hospitalization for young Aboriginal people.Note 7Note 8Note 9Note 10Note 11Note 12Note 13 Two studiesNote 7Note 8 reported an elevated rate of hospitalization for injury (intentional and unintentional) among children in areas with higher percentages of Aboriginal residents for all of Canada (excluding Quebec). However, geographic approaches tend to underestimate hospitalizations among subpopulations.Note 14

Information about hospitalization rates among Aboriginal children is needed to document causes and disparities, and to better understand resource use and service requirements. This study provides national counts (excluding Quebec) of acute care hospitalizations and the leading diagnoses for Aboriginal and non-Aboriginal children (ages 0 to 9) and youth (ages 10 to 19). Data are presented for First Nations people living on and off reserve, Métis, and Inuit living in Inuit Nunangat. The analysis is based on socio-demographic information (including Aboriginal identity) from the 2006 Census that was linked to hospital discharge records.Note 15

Data and methods

Data sources

Data from the 2006 CensusNote 16 for nine provinces (excluding Quebec) and the three territories were linked to the Canadian Institute for Health Information’s 2006/2007-to-2008/2009 Discharge Abstract Database (DAD). Long-form census respondents (about 20% of the non-institutional population) provided detailed socio-demographic information, including Aboriginal identity.Note 16 As well, rather than sampling households, all households in Nunavut, the Northwest Territories (excluding Yellowknife), Yukon (excluding Whitehorse), and all Indian reserves and settlements were asked to complete the long-form questionnaire.

Every year, the DAD consolidates about 3 million hospital records from all acute care facilities and some psychiatric, chronic rehabilitation, and day surgery facilities in Canada,Note 17Note 18Note 19 except Quebec. Because of that exclusion, residents of Quebec (including Inuit in Nunavik) are not represented in the linked data, nor are hospitalizations in Quebec of residents of other provinces and territories.

Hierarchical deterministic linkage was conducted using identifiers common to both the census and the DAD: date of birth, sex, and postal code. A validation study concluded that the linked file is suitable for health-related research and is broadly representative of the population of Canada.Note 15

An important limitation is the lower rate of census coverage, and also, eligibility to link to the DAD, for groups relevant to this analysis: individuals who identified as Aboriginal, children younger than age one, and youth aged 15 to 19.Note 15 Lower coverage means that Aboriginal children and youth tend to be underrepresented. Statistics Canada estimates that 10.6% of Aboriginal people living on reserve were missed by the 2006 Census.Note 20 About 94% of non-Aboriginal census respondents were eligible for linkage, compared with 89% of First Nations respondents, 93% of Métis respondents, and 92% of Inuit respondents. The likely impact is underestimation of hospitalization rates of Aboriginal children and youth and a possible downward bias. Because ages of the cohort were not adjusted (that is, “aged”) across the three years of combined hospital data, hospitalization rates for certain conditions are more likely underestimated, for example, respiratory-related among youth for some age-specific strata.

Linkage was conducted in accordance with the Directive on Record LinkageNote 21 and approved by Statistics Canada’s Executive Management Board.Note 22 Details about the linkage methodology are available elsewhere.Note 15

Statistics Canada ensures respondent privacy during linkage and subsequent use of linked files.Note 21 Only employees directly involved in the process have access to the unique identifying information (such as name and sex) required for linkage and do not access health-related information. When linkage is completed, an analytical file is created from which identifying information has been removed. Analysts are given access only to this de-identified file.

Aboriginal identity

The 2006 Census question on Aboriginal identity was: “Is this person an Aboriginal person, that is, North American Indian, Métis, or Inuit (Eskimo)?” The household member who completed the census responded for each household member and marked all that applied. Answers were classified as: North American Indian (only), Métis (only), Inuit (only), other Aboriginal (multiple or indeterminate), or non-Aboriginal. The present analysis includes only single-identity respondents; about 3% of the Aboriginal identity population reported other Aboriginal (multiple or indeterminate) identitiesNote 23 and were excluded.

The geographical location of census respondents was used to identify Inuit in Inuit Nunangat and First Nations people living on reserve (Indian reserves or settlements) or off reserve. Inuit counts are provided only for Inuit Nunangat, comprising the communities in the four Inuit land claim regions: Nunatsiavut (northern coastal Labrador), Nunavik (Northern Quebec), the territory of Nunavut, and the Inuvialuit Settlement Region of the Northwest Territories. Inuit Nunangat represents 78% of the total Inuit population. Inuit counts for this analysis exclude those in Nunavik because hospital discharges were not available for Quebec. As a result, 9,565 Inuit (19% of the total Inuit population, 24% of total Inuit in Nunangat)Note 23 were excluded.

The 2006 Census on-reserve population comprises residents of any of eight census subdivision (CSD) types legally affiliated with First Nations Indian bands, as well as other types of CSDs in northern Saskatchewan, the Northwest Territories, and the Yukon that have large concentrations of First Nations people. “On reserve” comprises legally defined Indian reserves, Indian settlements, other land types created by ratification of Self-Government Agreements, and other northern communities affiliated with First Nations according to criteria established by Indigenous and Northern Affairs Canada.

This study pertains to First Nations living on reserve, First Nations living off reserve, Métis, Inuit in Inuit Nunangat (excluding Nunavik), and the non-Aboriginal population. “Aboriginal” refers to members of these four Aboriginal groups; “Inuit” refers to Inuit in Inuit Nunangat excluding Nunavik.

Hospitalization

The frequency of hospitalizations by diagnostic category/chapter, based on “the most responsible diagnosis,” was compiled for each Aboriginal group and for non-Aboriginal children and youth. Individuals could be represented more than once if they were hospitalized multiple times during the 2006/2007-to-2008/2009 period.

Acute care DAD hospital discharge records linking to eligible long-form census respondents were classified based on the person’s census-reported Aboriginal identity and geographic location rather than the province where the submitting hospital was located. This enabled inclusion of hospitalizations that occurred in a province different from the respondent’s province/territory of residence at the time of the 2006 Census.

Most responsible diagnosis

Each hospital discharge record contains up to 25 diagnoses based on the International Statistical Classification of Diseases and Related Health Problems, 10th Revision, Canada (ICD-10-CA).Note 24 The “most responsible diagnosis,” which is the most significant diagnosed condition and/or accounts for the longest length of stay, was used to sort hospital records into chapters pertaining to specific diseases or injuries, etiology of the disease, conditions specific to body systems, or conditions and situations that are risk factors.Note 25 The first three characters of each most responsible diagnosis were used to classify hospitalizations by chapter. In accordance with previously used methods,Note 7Note 8Note 10Note 26 hospitalizations for injuries were categorized as unintentional or intentional injuries; intentional injuries among 10- to 19-year-olds were divided into assaults and self-inflicted injuries.

A frequency ranking was first applied to all in-scope linked census–DAD records to determine the most common diagnoses. The highest-ranking chapter codes, in addition to hospitalizations for all chapters combined, with and without pregnancy and child-birth-related hospitalizations, were selected to report hospitalization rates for each Aboriginal group and for non-Aboriginal children and youth.

Analytical techniques

Age-standardized hospitalization rates (ASHRs) per 100,000 population, age-standardized rate ratios (RRs) and 95% confidence intervals were calculated for each Aboriginal group and for the non-Aboriginal population. To reduce wide variations that can occur with small numbers, discharge records for the three fiscal years linked to 2006 Census long-form respondents were combined.

ASHRs used the sum of linked hospitalizations for a given identity group as numerators, divided by the denominator—unweighted person counts from the Census study cohort for the same identity group, multiplied by three (number of DAD years). Age standardization used the direct method, based on the age structure of the Aboriginal population according to the 2006 Census.

Age-standardized 95% confidence intervals for the ASHRs and RRs were derived with the Spiegelman method.Note 27 The non-Aboriginal population was the reference for RRs.

Results

All-cause hospitalization rates

Age-standardized acute care hospitalization rates among Aboriginal children and youth consistently surpassed those of their non-Aboriginal contemporaries. At ages 0 to 9, the overall hospitalization rate was highest for First Nations children living on reserve (839 per 100,000), which was 1.8 times that for non-Aboriginal children (478 per 100,000) (Table 1). Compared with non-Aboriginal 0- to 9-year-olds, rates were 1.4 times higher for First Nations living off reserve, 1.3 times higher for Métis, and 1.4 times higher for Inuit in Inuit Nunangat.

Among 10- to 19-year-olds, the overall hospitalization rate (including births) was highest for Inuit in Inuit Nunangat (1,866 per 100,000), which was 3.8 times that for non-Aboriginal youth (497 per 100,000) (Table 2). The rate was almost as high (1,806 per 100,000) for First Nations youth living on reserve—3.6 times that for non-Aboriginal youth. Rates for First Nations youth living off reserve and Métis youth were 2.3 and 2.0 times higher, respectively, than rates for non-Aboriginal youth. When hospitalizations related to births were excluded, overall rates at ages 10 to 19 were reduced but remained well above those for non-Aboriginal youth: 2.6 times higher for Inuit, 2.5 times higher for First Nations living on reserve, 1.8 times higher for First Nations living off reserve, and 1.6 times higher for Métis.

Leading causes

At ages 0 to 9, the top three causes of hospitalization were the same for each Aboriginal group and for non-Aboriginal children. The leading cause was “diseases of the respiratory system.” The second leading cause for children in all Aboriginal groups was “injuries, poisoning and other consequences of external causes,” followed by “diseases of the digestive system; among non-Aboriginal children, these causes ranked third and second.

For 10- to 19-year-olds in each Aboriginal group, the leading cause of hospitalization was “pregnancy, childbirth, and the puerperium,” followed by “injuries, poisoning and other consequences of external causes.” For non-Aboriginal youth, the ranking of these two causes was reversed. The third leading cause of hospitalization for First Nations (living on or off reserve) and Inuit youth was “mental and behavioural disorders.” For Métis and non-Aboriginal youth, “diseases of the digestive system” ranked third.

Rate ratios for children aged 0 to 9

At ages 0 to 9, the greatest disparities from non-Aboriginal hospitalization rates were among First Nations living on reserve, whose rate ratios were more than twice as high for “diseases of the respiratory system” (RR = 2.5), “unintentional injuries” (2.4), and “diseases of the genitourinary system” (2.2) (Figure 1).

For First Nations children living off reserve, the highest RRs were for “diseases of the genitourinary system” (1.8), “diseases of the respiratory system” (1.7), and “unintentional injuries” (1.7). The ranking and magnitude of RRs for Métis children were similar: “diseases of the genitourinary system” (1.9), “unintentional injuries” (1.8), and “diseases of the respiratory system” (1.7).

Among Inuit children, RRs for the top two conditions were similar to those for First Nations children living on reserve: “diseases of the respiratory system” (2.2) and “unintentional injuries” (2.0). Owing to the small sample size, RRs could not be reported for diseases of the genitourinary system; diseases of the endocrine, nutritional and metabolic systems; diseases of the circulatory system; and mental and behavioural disorders.

Rate ratios for youth aged 10 to 19

For First Nations 10- to 19-year-olds living on reserve, the highest RR was for “intentional injury (assaults),” with a rate 10.0 times that for non-Aboriginal youth (Figure 2). The next highest RRs were for “pregnancy, childbirth, and the puerperium” (9.3), “intentional injuries (self-inflicted)” (5.9), and “mental and behavioural disorders” (3.0).

RRs for First Nations youth living off reserve were lower, but the ranking was the same: “intentional injuries (assaults)” (6.9), “pregnancy, childbirth, and the puerperium” (4.9), “intentional injuries (self-inflicted)” (3.6), and “mental and behavioural disorders” (2.5).

For Métis youth, this ranking persisted: “intentional injuries (assaults)” (4.8), “pregnancy, childbirth and the puerperium” (4.1), “intentional injuries (self-inflicted)” (2.7), and “mental and behavioural disorders” (1.9).

For Inuit youth, RRs tended to be high, and the rank order differed. The highest RR was 14.4 for “intentional injuries (self-inflicted),” followed by “pregnancy, childbirth and the puerperium” (9.8), “intentional injuries (assaults)” (5.9), and “mental and behavioural disorders” (4.4).

Discussion

According to results from the 2006 Census-DAD linkage, Aboriginal children and youth were more likely than their non-Aboriginal contemporaries to be hospitalized. For 0- to 9-year-olds, overall age-standardized hospitalization rates were about 1.5 times higher. At ages 10 to 19, rates were 2.0 to 3.8 times higher. Rates were generally highest for First Nations living on reserve and for Inuit in Inuit Nunangat. These differences demonstrate the importance of examining hospitalization of children and youth for each Aboriginal group.

The leading cause of hospitalization at ages 0 to 9 was “diseases of the respiratory system” for each Aboriginal group and for non-Aboriginal children. However, First Nations children living on reserve and Inuit children were more than twice as likely as non-Aboriginal children to have been hospitalized for this reason. Housing conditions such as crowding and poor indoor air quality have been associated with respiratory problems among Aboriginal children and adults.Note 5Note 28

In the present analysis, “pregnancy, childbirth, and the puerperium” ranked high as a cause of hospitalization among First Nations, Métis, and Inuit youth. This is consistent with research showing that Aboriginal women are more likely than non-Aboriginal women to be teen mothers.Note 29Note 30 Teen motherhood has implications not only for the use of health care services, but also for educational and economic outcomes,Note 29 and has been associated with poorer physical and mental health of children.Note 31Note 32Note 33

The widest differences in hospitalization rates between Aboriginal and non-Aboriginal 10- to 19-year-olds were for intentional injuries: assaults among First Nations and Métis, and self-inflicted injuries among Inuit. Analyses that used geographic approaches also found elevated rates of unintentional injuries among children and of intentional injuries among youth in areas with higher percentages of Aboriginal residents.Note 7Note 8 Provincial studies, too, reported higher rates of both intentionalNote 12 and unintentionalNote 10Note 12Note 34Note 35 injuries among Aboriginal children and youth. The high RR for self-inflicted injuries among Inuit (14.2) reinforces the need for health prevention strategies.

Disparities in hospitalization rates between Aboriginal and non-Aboriginal children were apparent for “diseases of the genitourinary system,” particularly for First Nations living off reserve and Métis, although the overall number of hospitalizations was relatively small. In children, problems of the urinary system include acute and chronic kidney failure, urinary tract infections, obstructions along the urinary tract, and abnormalities present at birth.Note 36

High rates of hospitalization for Aboriginal children and youth may be associated with factors that were not taken into account in the present study and warrant consideration in future analyses. For instance, some differences could be related to less favourable socioeconomic conditions for Aboriginal children and youth.Note 37 The results could also reflect differences in access and barriers to care.Note 38 As well, differences in intentional injuries and mental disorders have been attributed to intergenerational effects of residential schools.Note 34Note 35

Limitations

Several limitations should be considered when interpreting the results. The lack of data for Quebec and for residents of 22 incompletely enumerated reserves suggests possible underestimation. In addition, mental health hospitalizations in Ontario were not comprehensively reported to the DAD, but instead, to the Ontario Mental Health Reporting System. Also, the census-DAD linked data under-represent children younger than age one. For these reasons, studies using other datasets are warranted.

The analyses were based on counts of hospitalizations and do not consider readmissions or reflect the number of persons hospitalized. Research exploring readmissions would be valuable in understanding resource use and health promotion strategies.

Although hospitalizations of children and youth do not place the largest burden on the health care system (about one-fifth of all hospitalizationsNote 39), they are important for long-term health and use of health care services.

Hospitalizations are a limited indicator of health status. These results cannot be interpreted as representing the prevalence of health conditions or injuries.

Conclusion

Unlike area-based estimates, this study presents national (excluding Quebec) information on acute care hospitalization of Aboriginal children and youth at the individual level. Age-standardized hospitalization rates were consistently higher among each Aboriginal identity group relative to non-Aboriginal children and youth. Future research could examine reasons for these disparities and how the rates and reasons vary by factors such as gender and geographic location.

Acknowledgements

The authors acknowledge the support of First Nations and Inuit Health Branch, Health Canada and the comments of the peer and institutional reviewers.

References
Date modified: