Background: Poverty is associated with poor outcomes, yet exposure to distinct poverty trajectories in early childhood is not well understood. Objective: To understand the prevalence of different trajectories of household poverty and their association with mid childhood and primary parent(mother) indicators of physical health and psychopathology in Ireland. Methods: We used a nationally representative, prospective cohort (Growing up in Ireland Infant Cohort). Household poverty included lowest third income decile, subjective poverty and material deprivation when children were aged 9-months(m),3,5,9 years(y). We used group based multi trajectory cluster modelling to classify trajectories of poverty. Using multivariate logistic regression, adjusted with separate child and mother confounders, we assessed the association of poverty trajectories from 9m to 9y with child outcomes (overweight, any longstanding illness and psychopathology) at age 9y and the same poverty trajectories over the same 9y period with mother outcomes (overweight, any longstanding illness and depression). Results: Of 11,134 participants, four trajectories were identified: never in poverty (43.1%), material/subjective>monetary poverty (16.1%), monetary>material poverty (25.6%), and persistent poverty (15.2%). Children in persistent poverty compared with never in poverty experienced higher odds of being overweight at 9y (adjusted odds ratio aOR 1.70,95% CI 1.34, 2.16), having a longstanding illness (aOR 1.51,95% CI 1.20, 1.91) and psychopathology (aOR 2.06,95% CI 1.42, 2.99). The outcomes for primary parent (99.7% were mothers) had higher odds of being overweight (aOR 1.49,95% CI 1.16, 1.92), having a longstanding illness (aOR 2.13,95% CI 1.63, 2.79), and depression (aOR 3.54,95% CI 2.54, 4.94). Conclusions: Any poverty trajectory was associated with poorer psychopathology and physical wellbeing in late childhood for children and their mothers in Ireland.

The authors have declared no competing interest.

This study did not receive direct funding.

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The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

The authors received approval from the Central Statistics Office to use the AMF Infant Cohort dataset. The GUI study received ethical approval from the Research Ethics Committee within the Irish Department of Health and Children, Ireland. All participants gave informed consent to enrol in the GUI study. This study is in accordance with the ethical standards as per the Declaration of Helsinki (1964) and subsequent amendments. The present analyses did not require additional ethical approval.

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Data may be accessed by applying to the Central Statistics Office of Ireland.