Co-development of anxiety and depression in UK and Brazil youth; a cross-country comparison

Importance

Anxiety and depression frequently co-occur and show developmentally patterned co-development from childhood to adolescence. Adult psychiatric outcomes vary according to the timing, sequencing, and persistence of early symptoms, yet it remains unclear whether patterns of co-development are comparable across high-income and low– and middle-income country contexts.

Objective

Examine joint developmental trajectories of anxiety and depression from childhood to adolescence and their associations with anxiety and depression diagnoses in young adulthood.

Design, Setting and Participants

Population-based prospective cohort studies in the UK (Avon Longitudinal Study of Parents and Children [ALSPAC], N=9,586) and Brazil (Pelotas 2004 Birth Cohort, N=3,815).

Main Outcomes and Measures

Trajectories were derived using parallel-process latent growth models and latent class growth analyses of anxiety and depression using the Development and Well-Being Assessment at early childhood (6–7 years), middle childhood (10–11 years), and adolescence (13–15 years). Diagnoses of anxiety and depression at 18 years were assessed via the Clinical Interview Schedule (ALSPAC) and the Mini International Neuropsychiatric Interview (Pelotas).

Results

Prevalence of anxiety and depression from early childhood to adolescence was similar across cohorts. Co-development was stronger in ALSPAC, with modest increases in both conditions, whereas in Pelotas, anxiety increased rapidly while depression showed little average change. In both cohorts, four trajectory classes were identified: stable-low (ALSPAC, 41%; Pelotas, 54%), increasing (31%; 28%), decreasing (23%; 15%), and persistent-high anxiety/increasing depression (5%; 3%). Compared with the stable-low class, youth in the increasing and persistent-high classes had elevated odds of depression (ALSPAC: OR=2.0 [95% CI, 1.4–2.8] and 4.2 [2.6–6.7]; Pelotas: 2.2 [1.5–3.3] and 2.9 [1.4–6.0]) and anxiety in young adulthood (ALSPAC: 1.6 [1.2–2.2] and 4.8 [3.2–7.0]; Pelotas: 1.7 [1.2–2.6] and 2.9 [1.5–5.8]). No increased risk was observed in the decreasing class.

Conclusions and Relevance

Patterns of anxiety and depression co-development were comparable across the UK and Brazil, suggesting shared developmental pathways. However, more rapid increases in anxiety among Brazilian youth may reflect context-specific risk factors. Persistence or emergence beyond early childhood was critical for identifying later diagnostic risk in both settings, highlighting the importance of early monitoring and intervention.

Key points

Question: How does the co-development of anxiety and depression from early childhood to adolescence differ between high-income (HICs) and low– and middle-income countries (LMICs)?

Findings: In this comparative longitudinal study of two population-based birth cohorts from the UK (N = 9,586) and Brazil (N = 3,815), trajectories of anxiety and depression co-development from childhood through adolescence were broadly similar across settings and were predictive of anxiety and depression diagnoses in young adulthood.

Meaning: Despite substantial socioeconomic and contextual differences between the UK and Brazil, developmental pathways of anxiety and depression co-development appear largely comparable, suggesting shared underlying developmental processes across these contexts.