Although we have no Indigenous comparison groups in this age range (13 – 15 years), we can compare the adolescents to current prevalence rates in the general population. In the National Comorbidity Survey Replication (NCSR), the lifetime prevalence for psychiatric disorder (ages 18 and older) was 46.4% for a single disorder and 27.7% for two or more disorders.16
The American Indian Service Utilization, Psychiatric Epidemiology, Risk and Protective Factors Project (AI-SUPERPFP) reported a lifetime prevalence rate for a single disorder of 41.% in a Southwest culture and 44.5% in a Northern Plains culture among Indigenous adult samples aged 15 – 54 years.15
Among the caretaker adults in Wave 1 of this study, we found a prevalence rate of 43% for a single lifetime disorder and 31.6% met criteria for two or more of five disorders (alcohol abuse, alcohol dependence, drug abuse, MDE, GAD). Our findings for the 13 – 15 year olds are similar (44.8 lifetime; 26.6% 12-month) to the adult prevalence rates reported in all of these adult samples.17
The high rates of psychiatric disorders are reflected in atypically high rates of SUD and externalizing disorders among the Wave 4 adolescents. Estimates of CD for adolescents in Western industrialized countries aged 8 – 16 years are between 5% and 10%.18–19
The rates we are reporting for lifetime CD (23.4%) are more than twice the highest rates expected in the general population. Similarly, SUD rates among adolescents are higher than those found in general population surveys. For example, the 2004 National Survey on Drug Use and Health (NSDUH) estimated that 9.4% of the population 12 years or older met criteria for substance dependence or abuse in the past year.20
The 12-month SUD rate (25.5%) reported in this study is nearly three times that of the NSDUH. Rates of lifetime alcohol abuse among adolescents range from 0.4% in the Great Smoky Mountain Study1
to 9.6% in the National Comorbidity Study.21
The lifetime rate for this study 13 – 15 year olds is 13.8%. General population rates of lifetime alcohol dependence range from 0.6%1
to 4.3% in the OADP.4
The lifetime prevalence of alcohol dependence in the current study is 7.2%. The life-time prevalence of drug abuse or dependence in general populations studies ranges from 3.3% in 15-year-olds to 9.8% in 17-to 19-year-olds. 22–24
The lifetime marijuana dependence rate for this cohort of adolescents is 12.4%, however, rates of abuse and dependence of drugs other than marijuana are very low.
General population studies of depression among children and adolescents under 18 years yield prevalence rates ranging between 1.6% and 8.9%.25
The rates of 12-month MDE (7.2%) for the Wave 4 adolescents were well within that range. Prevalence rates from population studies for childhood GAD range from 0.6 to 4.2% with a median of 2%.26
The 12-month rates among this cohort of adolescents (4.6%) fall at the high end of the reported range.
Impairment rates indicate at least moderate impairment for the majority of adolescents who met 12-month diagnostic criteria. Severe impairment decreased to about one-half of those who met 12-month criteria. These impairment estimates suggest that the prevalence rates represent serious deficits in psychosocial functioning at a critical stage in the adolescents’ development.
According to Kessler and colleagues17
estimates of age of onset vary widely by type of disorder. For example, they estimate the median age of onset for anxiety disorders and impulse-control disorders at 11 years, SUDs at 20 years and mood disorders at 30 years. Of particular interest here: “the median age of onset was earlier for each impulse-control disorder (7–15 years) than for any substance (age 19 – 23 years) or mood (age 25 –32 years) disorder” (p. 595). In contrast to the NCSR estimates, the 13 – 15 year old adolescents in our sample are manifesting about the same lifetime rates of externalizing disorders and SUDs. They are within the age range set by Kessler and colleagues for the onset of externalizing disorders but four to eight years earlier for onset of SUDs. They are also well below Kessler’s estimates for median age of onset for MDE.
The prevalence rates suggest two critically important trends among Indigenous children in mid-adolescence. First, the high percentage of SUD and CD children portend difficult late adolescent and early adult adjustment for about one-fourth of the young people. This is complicated by the fact that these are likely to be dual-diagnosis children. Comorbidity for lifetime CD with any lifetime SUD (combined caretaker and child reports) was 62%. These are the adolescents who are likely to perform poorly in school, who are at risk for school leaving, and who are likely to engage in risky sexual behaviors. They are also likely to be involved in the criminal justice system, and at risk for intentional and unintentional injuries. The reservations/reserves in the study are small, economically disadvantaged, and lack sufficient health, education, and social services resources to cope with such large numbers of severely troubled adolescents.
Second, those who met criteria for SUD and MDE were significantly “off time” for age of onset. The early onset of SUDs particularly may augur later life substance abuse problems and, perhaps, the transition in later adolescence and early adulthood to harder drugs or polydrug use.27
Early onset MDE tends to recur later during adolescence and in adulthood.28
Indeed, Kovacs found that five years after the first depressive episode, 72% had a recurrence.29
Numerous studies have shown a relationship between childhood onset of depression and adult depressive episodes.30–32
We are already noticing the effects of early disorders on later disorders in the multivariate analyses with odds ratios for pre-existing disorders ranging from 2.03 to 8.65.
Moreover, the multivariate analyses suggest intergenerational continuity of mental and substance use disorders. Having a biological mother who met lifetime criteria for SUD or an internalizing disorder about doubles the odds of her child meeting criteria for a psychiatric disorder. If the mother was comorbid for SUD and an internalizing disorder at Wave 1, the odds her child met criteria for an externalizing disorder at Wave 4 increased to over three times. Families in which the mother has a history of psychiatric disorder will likely to be those who will have the most difficulty coping with a child with a psychiatric disorder. The effects of social location are cumulative. Reservations lack resources to respond the high numbers of emotional and behavioral problems among the adolescents, and the families in which they reside may well be those least able to cope without support.
The cultural context of development
Growing up on a reservation/reserve represents a unique developmental context for these adolescents historically and socially. If the Indigenous nation was lucky enough not to be completely removed from their home territory, reservations/reserves represent the remnant “homeland.” However, this “homeland” often occupies the least productive, least desirable area of what was once their vast territory. Contemporary reservations are often economically disadvantaged, rural, and socially isolated from surrounding communities. As a social context, reservations/reserves are at once a symbol of what was and the representation of what has occurred. Simply living on reservations/reserves can be a reminder of ethnic cleansing, broken promises, continual encroachment on tribal lands, and continuing pressures of assimilation. At the same time, reservations/reserves may be a refuge from discrimination and the land a symbol of the living culture.
The adolescents in this study were subject to all of the known risk factors associated with economic disadvantage. However, there are also culturally unique protective factors such as traditional spirituality, traditional extended family and community support, and community elders available to them that are often overlooked in majority research. This is a unique cultural context that is not well understood by majority researchers and practitioners. More work needs done to identify and understand the interplay between majority and culturally specific risk and protective factors. We urgently need this work to guide therapeutic and prevention interventions.
The major limitation of this research is the is the sensitivity of DISC-R and UM-CIDI measures for assessing American Indian and Canadian First Nations people. For example, definitions of depression may vary across Indigenous cultures.33
and drinking patterns among Indigenous adults may include sporadic binge drinking at irregular intervals that may not be represented adequately by diagnostic criteria.34
However, this study uses the same measures as recent population studies of American Indian people to provide the best estimates possible.15
A related measurement issue is that cultural variations in the expression of some symptoms, particularly internalizing symptoms may be poorly represented in diagnostic interview schedules. 33, 34
Externalizing symptoms on the other hand are more overt and easier to identify. This may lead to under estimating prevalence of internalizing disorders in comparison to externalizing disorders.
Although we interviewed a broad range of American Indian and Canadian First Nations adults and children on multiple reservations and Canadian reserves that are dispersed geographically across two Midwestern states and one Canadian province, these results pertain to a single culture and capture variations within this culture. We believe the findings represent the culture well, but they cannot be generalized to other Indigenous cultures. However, if we are to obtain sound psychiatric epidemiological information pertaining to Indigenous people, it will be necessary to proceed nation by nation with comparable measures.35
A final concern is that this report is limited to 11 diagnoses for children and only 4 diagnoses for the biological mothers. This limitation was dictated by time, subject burden, and sensitivity of the nations to certain diagnostic questions (e.g., antisocial personality disorders, posttraumatic stress disorder; psychoses).
This research has important clinical and policy implications for Indigenous communities. It is the only diagnostic longitudinal study of which we are aware that addresses change in prevalence rates from early to mid-adolescence among Indigenous youth. The findings show a dramatic increase in prevalence rates for SUD and CD between ages 10 – 12 years and 13 – 15 years among Indigenous adolescents, with these disorders affecting more than one-fourth of the children. We have long known that Indigenous adolescents begin substance use earlier than their counterparts from other ethnic groups.36
This research charts the trajectory of those most at risk.
These results call attention to the critical need for mental health services on Indigenous reservations and reserves. These numbers would overwhelm any pediatric health system, but these communities are among the least prepared in the Nation to respond effectively. Indeed, these findings are one more blow to communities that are struggling to overcome the psychological effects of three hundred years of systematic ethnic cleansing. Though beyond the scope of this paper, empirical evidence is beginning to emerge linking historical losses to mental health and substance use symptoms of Indigenous people.37
Such high rates of mental and substance abuse disorders are indicative of this historical legacy.
Few services exist to address these mental health disparities, distances are great, there is distrust about confidentiality, and there are very few well-trained mental health workers on the reservations and reserves and almost none of these are Indigenous. As we have reported elsewhere, parents do not have a high regard for existing reservation/reserve mental health and SUD services and prefer traditional helpers to those within the formal health system. As mental health systems on the reservations/reserves evolve, it will be important to include traditional healers, and mental health workers who are knowledgeable and sensitive to traditional cultures.38
The findings also indicate the need for parent and teacher training in structuring and providing limits for children and adolescents manifesting early disruptive behaviors. CD at Wave 1 of the study was just a little higher than that found in general population studies, but doubled in the following three years. It may be that we have a window of opportunity during early adolescence to prevent the rapid increase in serious behavior problems through family and school interventions. We must work to understand the specific mechanisms that contribute to this upsurge in disruptive behaviors. The odds ratios in multivariate analyses for Wave 1 SUD and CD on Wave 4 SUD and CD attest to the importance of identifying and treating those with early onset problem behaviors. The strong effects of maternal psychopathology on child outcomes also denote the risks of intergenerational effects and the need for effective family interventions.
Such high rates of mental and substance use disorders at these early ages should alarm state and national mental health policy makers. Tribal members see the consequences daily in early drug use, violence, suicides, and unintentional injuries among their young people. These findings attest to their sense of urgency for the health and safety of the next generation and the need for immediate policy changes to address the mental health disparities associated with rural reservation life.