The prevalence of psychiatric disorders among Vietnamese children and adolescents

Many Vietnamese immigrants have been deeply affected by traumatic post-war and migratory events and the stresses inherent in making the transition between vastly different cultural traditions.1-3 Such experiences may lead to psychological problems. Studies of psychiatric disorders among children and adolescents in the general Australian population4-7 report prevalence rates of 14%–21% and suggest higher rates among refugee than non-refugee children.

In our study we sought to determine the prevalence of psychiatric disorders in Vietnamese children and adolescents living in Perth, Western Australia. Such data are needed in order to plan effectively for the mental health needs of this important ethnic minority population.8

Two previous studies2,3 of the prevalence of psychiatric disorders among the children of Vietnamese refugees have produced somewhat contradictory results. Both studies interviewed children but not parents. Krupinski and Burrows3 reported a prevalence of 18.2% for "definite disorders" and 32.0% for "definite and probable disorders" among a cohort of Vietnamese children, adolescents and young adults newly arrived in Victoria. Initially, these rates were higher than those among native-born Australians. However, two years after resettlement, the rates had fallen to 4.4% and 6.6%, respectively, which were substantially lower than those of the general population.3

Holzer et al2 assessed mental disorders among Vietnamese children aged 10–18 years living in Texas.2 The study reported a 36.0% prevalence of psychiatric disorders, which was higher than that found in community-based populations of children in developed countries (typically about 20%9).

Studies of psychiatric disorders in refugee children from various other countries who have resettled abroad10-13 generally report a higher prevalence rate of psychiatric disorders in these children than in non-refugee children living in the same countries.

For simplicity, we use the term "children" to refer to both children and adolescents in this article.

The 18.3% combined prevalence (DISC-C or DISC-P) of psychiatric disorders in our study was similar to the 17.9% prevalence of psychiatric problems for the general child and adolescent population of Western Australia.6 It is also similar to prevalence rates in other parts of Australia4,5,7 and other Western countries.9 It is substantially lower than the prevalence of disorders found among Vietnamese children in the Texan2 and initial Victorian3 studies. On the other hand, it is much higher than the rate of disorders found at two years' follow-up in the Victorian study.3

Our subjects' more limited exposure to the traumas of war and migration (only 5% had experienced or witnessed traumatic events) and their longer time in Australia may help explain the lower rate of disorders found in our study compared with the Texan study and the Victorian initial sample. Furthermore, our study was conducted about 10 years after the other two. All of the children in the Victorian study and 91% of those in the Texas study were born in Vietnam, compared with 53.8% in ours.2,3 Only 5.3% of participants in our study had lived in their new homeland for two years or less, compared with 21.3% in the Texan study and 100% in the Victorian study. There appears to be a direct and negative correlation between the length of time Vietnamese children have spent in their new homeland and the prevalence of mental disorders experienced by them.3

There are several other possible reasons for the lower rate of psychiatric disorders found in our study. One may have been the relative size of the Vietnamese populations assessed. At the time the Texan study2 was conducted there were about 51 300 Vietnamese living in Texas.2 At the time of our study, there were about 9300 Vietnamese living in Perth.8 Thus, it was more likely that our interviewers would know the people they interviewed, which may have made some parents reluctant to disclose potentially negative information.1,15-17 Another reason may have been the inclusion of more than one child from each household. Parents had to complete a separate DISC-P for each child, and may have learned that saying "no" to interview queries about symptoms would reduce the amount of time required for each interview. Finally, the inclusion in our study of children less than 11 years of age, for whom the DISC may be less reliable, may have affected prevalence rates.18

Given the high rates of disruptive behaviour disorders in Australia (eg, the prevalence rate of attention-deficit hyperactivity disorder is about 7.5%19), it is surprising that only two Vietnamese parents and children reported them. There are several possible explanations for this: Vietnamese parents may not want to acknowledge their children's unacceptable social behaviours, they may be more tolerant of children's mental health problems than parents in Western countries,20 or disruptive behaviour disorders may be less common among Vietnamese children.

Vietnamese parents reported a very low rate (4.4%) of DSM-III-R disorders and an even lower rate (0.5%) of poor mental health in their children. This reinforces previous findings that Vietnamese and non-Vietnamese Australian parents may have different concepts of what behaviours and feelings constitute a "psychiatric problem" in a child.1

The very low concurrence between the disorders reported by parents and children in our study is a problem shared with other studies using the DISC-2.3.21 It is believed to reflect "situation-specific problems, a child's experience of subjective states of distress that is not shared with the parent ... [and] differences in value systems and in the threshold for judging a behavior to be abnormal".21 Unusual, however, is the large discrepancy between child- and parent-reported rates of disorder. This may be related to parental under-reporting. It may also reflect the inclusion of the diagnoses of simple and social phobias — conditions more likely to be recognised and reported by children than parents.

The high rate of anxiety disorders in our study may reflect problems in the DSM-III-R, on which the DISC-2.3 is based.21 Unlike the later version, DSM-IV, whose diagnoses require significant functional impairment in addition to symptom criteria, the DSM-III-R diagnoses do not, and may lead to an overestimation of the prevalence of anxiety disorders.21

Finally, the DISC-2.3 reflects Western concepts of psychiatric disorders. While it has shown considerable utility in cross-cultural populations, it may embody concepts that do not reflect a Vietnamese understanding of child mental illness.1 Furthermore, the Vietnamese people involved in translating and testing the instruments were almost all urban-dwellers and university graduates, unlike the predominantly rural-origin, non-university-educated Vietnamese who were the parents of our subjects.

Our results suggest several important considerations for clinicians treating the children of Vietnamese refugees and immigrants. The prevalence of psychiatric disorders among them is similar to the rate found among native-born children in Australia and other Western countries. In addition, Vietnamese children are more likely to report anxiety disorders than other psychiatric disorders. Finally, Vietnamese parents are unlikely to recognise, or, if recognised, to report, child psychiatric disorders as they are defined in Western countries. These findings emphasise the need to develop clinical services that are sensitive to Vietnamese cultural traditions that may affect the recognition, reporting and treatment of child and adolescent psychiatric disorders.