data on the adult ( over 20 years ) population has been reported elsewhere ( 5 ) . the present analysis focused on albertan youth < 20 years of age .
flagged in the databases and were defined as any alberta inhabitant registered under the federal indian act and entitled to treaty status with the canadian government .
the status aboriginal identifier captures first nations and inuit peoples both on- and off - reserve with treaty status , but not mtis individuals or aboriginal individuals without treaty status who are included in the general population comparison group .
alberta law requires that all residents and dependants register with the alberta health care insurance plan , thus the alberta central stakeholder registry functioned as a denominator .
diabetes cases were identified by applying the national diabetes surveillance system ( ndss ) algorithm ( 13 ) , which has recently been validated for the determination of pediatric diabetes rates ( 14 ) .
the ndss methodology of identifying has been validated in non - aboriginal populations that include persons of varying geographical locations ( 15,16 ) , and also within an aboriginal community in alberta ( 17 ) .
the algorithm requires an individual to have either 2 physician visits or 1 hospitalization for diabetes ( icd-9 codes starting with 250 and icd-10 codes e10e14 ) within 2 years to be labelled as case of diabetes ( 13 ) .
in contrast to the ndss case definition , pregnant women that may have had gestational diabetes were not excluded in the current analysis due to the elevated risk of subsequent diabetes ( 18 ) . also , since the numbers of diabetes cases are small among this population , only crude , unadjusted rates are provided . for both populations ,
the denominators were based on the health insurance registry ( which provincial law requires all residents and dependants to register ) for the entire population as of june 30 in each year .
the first year in which an individual met the criteria for diabetes ( with no diabetes claims in the preceding 2 years ) was considered an incident year , and considered a prevalent case in subsequent years .
prevalence was determined using the following group - specific formula : total number of youth with diabetes in the calendar year / the total population for the calendar year .
incidence was determined using the following formula : total number of youth with a diabetes incident date for in calendar year/(total population count for calendar year)(prevalent diabetes cases)+(incident diabetes cases ) .
odds ratios ( or ) and 95% confidence intervals were calculated and used to compare the likelihood of being a prevalent case and incident case of diabetes for the 2 populations in 2007 . or 95% confidence intervals that did not include the null value of 1.00 were considered statistically significant with a 5% error . to examine trends over time , average annual percent changes ( aapc ) in prevalence and incidence from 1995 to 2007 were determined and compared using joinpoint version 3.4.2 ( rockville , md ) for crude values .
the aapc provides a relative summary measure of the trend over a pre - specified fixed interval .
tests of parallelism were then performed to determine if trends over time differed by group or sex .
the denominators were based on the health insurance registry ( which provincial law requires all residents and dependants to register ) for the entire population as of june 30 in each year . the first year in which an individual met the criteria for diabetes ( with no diabetes claims in the preceding 2 years )
prevalence was determined using the following group - specific formula : total number of youth with diabetes in the calendar year / the total population for the calendar year .
incidence was determined using the following formula : total number of youth with a diabetes incident date for in calendar year/(total population count for calendar year)(prevalent diabetes cases)+(incident diabetes cases ) .
odds ratios ( or ) and 95% confidence intervals were calculated and used to compare the likelihood of being a prevalent case and incident case of diabetes for the 2 populations in 2007 . or 95% confidence intervals that did not include the null value of 1.00 were considered statistically significant with a 5% error . to examine trends over time , average annual percent changes ( aapc ) in prevalence and incidence from 1995 to 2007 were determined and compared using joinpoint version 3.4.2 ( rockville ,
the aapc provides a relative summary measure of the trend over a pre - specified fixed interval .
tests of parallelism were then performed to determine if trends over time differed by group or sex .
based on alberta health and wellness administrative databases , 853,733 youth ( 51.2% male ) were living in the province as of 2007 , of which 50,930 were status aboriginal ( 51.2% male ) . among these youth
a total of 2,589 prevalent diabetes cases were apparent in 2007 , with 140 cases occurring amongst status aboriginal youth .
the 2007 crude prevalence rate of diabetes was 0.27 and 0.31% in the status aboriginal and general population youth populations respectively ( fig . 1 , table i ) .
incidence was 0.59 per 1,000 for status aboriginal and 0.49 per 1,000 for general population .
no discernible differences were seen in diabetes prevalence or incidence with respect to group or sex in 2007 ( fig . 1 ,
crude rates of diabetes among status aboriginal and general population youth in alberta , 19952007 ( adss ) . a = prevalence ; b = incidence .
crude diabetes prevalence and incidence among status aboriginal and general population youth , 2007 crude rates of both diabetes prevalence and incidence increased in status aboriginal and general population youth over the observation period ( fig . 1 , table ii ) .
however , prevalence grew to a greater extent among status aboriginal youth ( aapc 6.98 ) compared to those in the general population ( aapc 3.93 ; p < 0.01 ) , with status aboriginal males experiencing the largest increase in diabetes prevalence ( aapc 9.18 ) .
ethnic differences in diabetes incidence trends were only observed among the male population , which saw a significantly larger rise in incidence for status aboriginal ( aapc 11.65 ) compared to general population males ( aapc 4.62 ; p < 0.01 ) .
male youth , regardless of group , experienced greater increases in both prevalence and incidence over time than that of respective female youth ( table ii ) .
age - specific crude prevalence and incidence of diabetes by group are shown in fig .
2 . age specific crude rates of diabetes among status aboriginal and general population youth , 1995 and 2007 .
ethnicity comparisons of aapc ( average annual percent change ) in diabetes prevalence and incidence among status aboriginal and general population youth , 19952007 p < 0.05 for aapc ethnicity comparison .
paralleling adult populations , diabetes among youth is increasing worldwide ( 20 ) . while type 1 diabetes remains
the majority of cases in youth , type 2 diabetes ( a disease typically regarded as an adult phenomenon ) is becoming progressively more common in children and adolescents ( 20 ) .
we report that youth - onset diabetes is an increasing problem in alberta , especially among status aboriginals .
though our results are in line with international data showing increasing trends ( 20,21 ) , they contradict the recent ndss reports ( 12,22 ) , which found diabetes prevalence and incidence rates remained stable at 0.3 and 0.4 ( per 1,000 ) respectfully among general population youth between 20012006 .
it is possible that differences in ethnicities and/or socioeconomic parameters contribute to these differences . among indigenous populations
especially , including american indian / alaskan natives , australian aborigines , the maori of new zealand , and canadian aboriginals , youth - onset diabetes is increasingly being identified ( 14,2327 ) . in canada
, longitudinal trends of diabetes in aboriginal youth had previously only been explored in manitoba .
dean and colleagues ( 10 ) showed the crude type 2 diabetes incidence rate rose to 0.55/1,000 ( for ages 019 ) in 2001 . similarly ,
crude diabetes incidence increased from 0.22 per 1,000 to 0.59 per 1,000 over a 12 year time span in the current analysis .
the observed accelerated increase in diabetes among status aboriginal youth is consistent with reports of a decrease in the age of diagnosis of diabetes among aboriginal adults . in saskatchewan
type 2 diabetes incidence was highest among status aboriginal adults aged 4049 , while most new diabetes cases among the general population were in those > 70 years of age ( 4 ) .
also , as indicated by the first nations and inuit regional health survey , the majority ( 53% ) of those with diabetes in aboriginal communities were < 40 years of age ( 28 ) . compared to general population , diabetes grew approximately twice as much among status aboriginal youth .
ethnic comparisons have remained largely unexplored in youth , despite numerous studies documenting the divergence in diabetes epidemiology in adult populations . in the beginning of adss observation 1995 , incidence and prevalence of diabetes were distinctly higher among general population . by 2007
however , status aboriginal youth have  caught up to the point where no detectable differences were apparent , likely ( as mentioned above ) due to type 2 diabetes . reinforcing this notion ,
a recent national surveillance study amongst practicing physicians found the incidence of type 2 diabetes among aboriginal children ( 0.23/1,000 ) was strikingly 46-fold higher than caucasian children ( 0.005/1,000 ) over a 24 month period ( 29 ) .
we observed an increased rise of diabetes among young status aboriginal males , confirming earlier studies .
sex ratios of prevalence and incidence ( female : male ) of approximately 4:1 and 2:1 in 1995 decreased to 1:1 and 1:1 respectively in 2007 .
additionally , the aapc in prevalence was highest amongst status aboriginal males ( aapc 9.18 ) compared to females ( aapc 5.70 ) . over a 15 year time period in manitoba , the early predominance of youth diabetes cases among aboriginal females ( 8-fold compared to males ) disappeared by 2001 ( 10 ) . from 1990 to 1998
, american indian and alaskan native young males also experienced relative increases in diabetes prevalence almost double that of their female counterparts ( 30 ) .
similarly , the gap in diabetes prevalence between adult status aboriginal females and males is also diminishing ( 4,5 ) .
reasons for the accelerated rise of diabetes among status aboriginal males have not been explored , but may be due in - part to escalating childhood overweight and obesity ( 31 ) with a possible gender - based lag in the obesity epidemic where it may have occurred earlier in time amongst females . in countries with universal healthcare , administrative data have become common and invaluable sources for the population - based surveillance of many chronic diseases .
ndss methodology has been validated in adults and youth , and is a standard for diabetes monitoring at the population level ( 16,18,32,33 ) .
for instance , guttmann et al . ( 33 ) recently found the ndss algorithm in youth ( 019 years of age ) in ontario was associated with 100% sensitivity and 94% specificity . using a similar algorithm ( 4
physician claims over a 2-year period ) , diabetes prevalence rose from 0.18 to 0.24 and incidence ( per 1,000 ) increased from 0.25 to 0.32 among ontarian youth between 1994 and 2003 ( 32 ) . in support , general population youth in the current study experienced nearly identical increases in prevalence and incidence between 1995 and 2003 : 0.19 to 0.25 and 0.22 to 0.32 ( per 1,000 ) respectively , with rates progressively increasing until the end of the study period in 2007 .
we are unable to distinguish the type of diabetes in our administrative data . however , our clinical experience suggest that the majority of the diabetes in aboriginal youth is type 2 diabetes , whereas in the non - aboriginal population it is heavily dominated by type 1 diabetes .
moreover , rates of type 1 diabetes are much lower among american indian and canadian aboriginal youth compared to the general population historically ( 34 ) .
future research aimed at describing the contribution of both type 1 and type 2 diabetes to the observed trends is warranted .
possible gestational diabetes cases were included and may have inflated rates in status aboriginal as gestational diabetes has been shown to be more common in adult aboriginal populations ( 35 ) .
it is possible that increased awareness and screening in youth may have contributed to the observed increases , however for various projects ( http//:www.braiddm.ca ) we have screened 799 youth at risk ( mostly aboriginal ) in rural alberta since 2001 and have found only 3 ( 0.4% ) of those had undiagnosed diabetes ( unpublished ) . by contrast , the rates of undiagnosed diabetes are approximately 4% in at risk adults .
thus , it appears that diabetes in youth is not often asymptomatic , and therefore is less likely to be detected by increased awareness and screening .
our results can not be generalized to non - registered aboriginal or mtis youth , whom could not be identified and were included in the general population group .
also , due to the small number of diabetes cases in youth , age - standardized prevalence and incidence rates were not calculated and only crude rates were reported .
lastly , amendments to the indian act in 1985 are possibly increasing the status aboriginal denominator ( bill c-31 ) and likewise some descendants of status aboriginal people are losing their status through the  three generations  rule ( 36 ) . taken together , prudence is needed when interpreting the observed epidemiological findings . in conclusion
, diabetes prevalence and incidence has increased among all alberta youth from 1995 to 2007 .
status aboriginal youth , males in particular , experienced a disproportionate growth in diabetes . if unabated , increasing diabetes in youth will likely only further perpetuate the diabetes epidemic in the status aboriginal population .
type 2 diabetes is typically the  tip of the iceberg as it is often preceded by several co - morbidities ( obesity , hypertension , metabolic syndrome , pre - diabetes , etc ) , rendering its increased diagnosis in youth a potential public health crisis .
this work was supported in part by a team grant to the alliance for canadian health outcomes research in diabetes ( achord ; reference # : otg-88588 ) , sponsored by the canadian institutes for health research institute of nutrition , metabolism and diabetes .
this study is based in part on de - identified data provided by the alberta health and wellness .
 objectivesto track and compare trends in diabetes rates from 1995 to 2007 for status aboriginal and general population youth.study designlongitudinal observational research study ( quantitative ) using provincial administrative data.methodsde-identified data was obtained from alberta health and wellness administrative databases for status aboriginal ( first nations and inuit people with treaty status ) and general population youth ( < 20 years ) . 
 diabetes cases were identified using the national diabetes surveillance system algorithm . 
 crude annual diabetes prevalence and incidence rates were calculated . 
 the likelihood of being a prevalent case and incident case of diabetes for the 2 populations was compared for the year 2007 . 
 average annual percent changes ( aapc ) in prevalence and incidence from 1995 to 2007 were determined and compared between the 2 groups to examine trends over time.resultswhile the prevalence of diabetes was higher in the general population in 1995 , by 2007 there were no between group differences , reflected in the significantly higher aapc of 6.98 for status aboriginal youth . status aboriginal males had a lower diabetes risk in 1995 compared with females , and experienced a greater increase in prevalence over the 13 years ( aapc 9.18 ) so that by 2007 their rates were equivalent to those of the females . 
 differences in diabetes incidence trends were only observed among male youth , where increases in incidence were greater for status aboriginal ( aapc 11.65 ) compared to general population males ( aapc 4.62 ) ( p = 0.03).conclusionyouth - onset diabetes is an increasing problem in alberta , especially among young status aboriginal males . 
Methods
Statistical analysis
Results
Discussion
Conflict of interest and funding