Increasing knowledge on adolescent mental health in low- and middle-income countries: The National Adolescent Mental Health Surveys

TL;DR

The National Adolescent Mental Health Surveys study mental health in adolescents from Kenya, Indonesia, and Vietnam, revealing low disorder prevalence and highlighting lessons for global mental health.

Contribution

The study provides the first large-scale data on adolescent mental health in LMICs, offering insights into low prevalence and potential protective factors.

Findings

Mental disorder prevalence in adolescents is low in Indonesia and Vietnam.

The study identifies risk and protective factors for adolescent mental health in LMICs.

Baseline data is established for future mental health trend comparisons in these countries.

Abstract

There are limited prevalence data available for mental disorders in adolescents living in low- and middle-income countries (LMICs). The National Adolescent Mental Health Surveys (NAMHS) measured the prevalence of six common mental disorders, along with self-harm and suicidal behaviours, associated risk and protective factors, and service use in adolescents aged 10–17 years in Kenya, Indonesia, and Vietnam. The challenges and opportunities arising from large scale epidemiological mental health research in low resource settings are discussed.

Diagnostic criteria for mental disorders are largely informed by evidence and experiences from high-income countries. NAMHS reports a low prevalence of adolescent mental disorders in Indonesia and Vietnam, suggesting there is much that the Global North can learn from the Global South in relation to population mental health. Improving population mental health requires a public health approach which focuses on promotion of wellbeing, increased community cohesion, and prevention of exposure to risk factors in early life.

NAMHS significantly advances knowledge of adolescent mental health in LMICs. These data provide a baseline from which future trends of mental health in these countries can be compared. This will be increasingly important as the world faces ongoing challenges, such as conflict and climate change, which will inevitably affect global mental health.

Full text

Background

A significant proportion of the global burden of disease in adolescents is attributable to mental disorders [1]. Almost half of all individuals with mental disorders will experience first onset of illness by 18 years of age [2]. However, few studies have examined the prevalence of mental disorders in adolescents living in low- and middle-income countries (LMICs) [3] where more than 90% of the world’s adolescent population live [4].

Utilising the Diagnostic Interview Schedule for Children, Version 5 (DISC-5), the National Adolescent Mental Health Surveys (NAMHS) measured the prevalence of six common mental disorders (social phobia, generalised anxiety disorder, major depressive disorder, posttraumatic stress disorder, attention-deficit/hyperactivity disorder (ADHD), and conduct disorder), along with 12-month and lifetime self-harm and suicidal behaviours, associated risk and protective factors, and service use in adolescents aged 10–17 years in Kenya, Indonesia, and Vietnam. All adolescent participants were provided with short definitions of suicide and self-harm before answering the relevant questions. Self-harm was defined as “deliberately hurting or injuring yourself without trying to end your life” whilst suicide or attempted suicide was “taking some action to try and end your own life”.

Adolescents and their primary caregivers were interviewed from households selected randomly according to sampling frames specifically designed to elicit nationally representative results with very high participation rates in all countries. There were striking differences in the prevalence between countries with mental disorders, self-harm, and suicidal behaviour being much less common in Indonesia and Vietnam compared to Kenya [5]. Key findings presented in this Supplement include:

1. Substantial between-country variation in the prevalence of adverse childhood experiences (ACEs) [6] and bullying victimisation and perpetration [7]. Exposure to ACEs or bullying was associated with increased risk of mental disorders.
2. A significant proportion of adolescents identified as sexually or gender diverse in Indonesia and Vietnam [8]. They had increased odds of depressive and anxiety symptoms, as well as suicidal ideation.
3. A minority of adolescents with mental disorders accessed services for emotional or behavioural problems [9]. Adolescents who were supported by caregivers or peers had significantly lower prevalence of any mental disorder in the past 12 months compared to those who perceived they had limited support [10].

The hitherto absence of national prevalence surveys in LMICs reflects the significant challenges in conducting this type of research. Multiple factors impede large epidemiological studies in LMICs, including a lack of research capacity and infrastructure, scarcity of funding and resources, within-country linguistic and cultural diversity, and the increased likelihood of political instability and conflict. NAMHS was possible through an enduring research collaboration across five countries, enabled by philanthropic financial support [11].

Priorities

Historically, research into physical illnesses has been prioritised over mental health in low-resource settings. Consequently, disease burden estimates of mental disorders for LMICs, which inform government policies, are often modelled using approximations due to the absence of available data, leading to wide uncertainty intervals and a subsequent inability to track changes over time. Without epidemiological evidence, the burden of mental disorders in LMICs will be overlooked and the omission of mental health as a health priority perpetuated.

Challenges of measurement

Measuring mental disorders with instruments such as the DISC-5, which assesses mental disorder diagnoses in accordance with the American Psychiatric Association’s Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) [12], may result in measurement variance between countries. Expressions of distress vary significantly between cultures, influencing the phenomenology of mental illness resulting in differences in illness presentations. Research on the validity of DSM-5 diagnoses in adolescents living in the Global South is limited [13]. Categorical diagnoses have limitations when measuring population mental health. Mental illness is dimensional and diagnostic thresholds are somewhat arbitrary. However, diagnoses have the advantage of identifying those individuals whose mental health symptoms are both persistent and impairing.

Whilst problems in diagnostic validity across cultures may result in an underestimate of adolescent mental disorder prevalence in LMICs, it is less likely that behaviourally-orientated items about self-harm or suicide or questions about ACEs would be misinterpreted. There were very low rates of endorsement of these items in Indonesia and Vietnam as compared to Kenya, suggesting a true prevalence difference between countries, noting that ACEs are risk factors for mental disorders. The between country variation in the prevalence of risk factors, suicidal behaviours, and mental disorders are remarkably consistent and match the relatively low rates of suicidal thoughts previously reported in adolescents from Asian countries [14].

Mental illness is multi-dimensional with many adolescents experiencing sub-diagnostic and transdiagnostic symptoms, which cause significant distress and impairment. The threshold required for the diagnosis of a mental disorder according to DSM-5 may result in under-recognition of a significant proportion of the population who are symptomatic. Responses to individual items on the DISC-5 from NAMHS are available and will be analysed in future studies.

The low prevalence of adolescent mental disorders in Indonesia and Vietnam suggests there is much that the Global North can learn from the Global South. Substantial investment in mental health services in high-resource settings have failed to improve population mental health [15]. A 2011 review reported the effective implementation into primary health care services of mental health care for children living in low resource settings [16]. Improving population mental health requires a public health approach with promotion of strategies to promote wellbeing, prevention of exposure to risk factors particularly in early years of life, and ensuring people living with mental disorders are supported and experience a sense of purpose [17]. Further research is needed to understand factors which are responsible for the inter-country variation in prevalence and identify risk and protective factors which can inform population-based preventative interventions.

Stigma

Stigma, which encompasses the experience of negative attitudes and beliefs resulting from mental illness, may be internalized (self-stigma) or propagated by others including family members, peers, health care workers and the wider community [18]. Stigma is a significant impediment to the measurement of mental disorders in in LMICs, as individuals fear revelations about their illness may bring shame upon themselves or their families or they may be judged negatively by others.

Whilst it is possible that stigma influenced participant responses in NAMHS, strategies were implemented to minimize this risk. Experienced interviewers were comprehensively trained, privacy of all participants ensured (including for the adolescent from the primary caregiver), and substantial community consultation was undertaken in sampled areas prior to the commencement of data collection. Questions on particularly sensitive issues were self-administered by the adolescent.

Importance of measurement

NAMHS provides population-based data on mental disorders that are essential to supporting the 2030 Sustainable Development Agenda. Target 3.4 aims to reduce premature mortality from non-communicable diseases by one third through promotion, prevention, and treatment targeting mental health and well-being [19]. Measurement of adolescent mental disorders has been identified as a priority in improving global adolescent health [20]. Two other initiatives are underway to provide population-based data on mental health in adolescents living in low-resource settings. The United Nations Children’s Fund (UNICEF) has implemented the Measuring Mental Health Among Adolescents at the Population Level (MMAPP) project (20), which aims to use symptom scales to estimate the prevalence of mental health problems in low-resource settings. Additionally, the World Health Organization (WHO) is undertaking the Global Action for Measurement of Adolescent Health (GAMA) Initiative, which aims to identify and define a core set of adolescent health indicators including those related to mental health [21].

Conclusion

NAMHS significantly advances knowledge of adolescent mental health in the Global South. High quality, large-scale epidemiological research is critical to informing health policy. This must be complemented by the development and validation of measures that capture the wide-ranging symptoms of distress experienced in different cultures and health service research to examine the effectiveness and cost effectiveness of interventions in low resource settings [22]. Repeated population-based surveys from over a decade ago revealed a striking increase in the prevalence of mental disorders in female adolescents living in high-income countries [23]. NAMHS will enable trends of mental health in the Global South to be tracked in the years to come. This will be increasingly important as the world faces ongoing challenges such as climate change [24] and unforeseen events such as the COVID-19 pandemic [25] which will inevitably affect global mental health.