Social and environmental factors such as poverty or violence modulate the risk and course of schizophrenia. However, how they affect the brain in patients with psychosis remains unclear.

We studied how environmental factors are related to brain structure in patients with schizophrenia and controls in Latin America, where these factors are large and unequally distributed.

This is a multicentre study of magnetic resonance imaging in patients with schizophrenia and controls from six Latin American cities. Total and voxel-level grey matter volumes, and their relationship with neighbourhood characteristics such as average income and homicide rates, were analysed with a general linear model.

A total of 334 patients with schizophrenia and 262 controls were included. Income was differentially related to total grey matter volume in both groups (P = 0.006). Controls showed a positive correlation between total grey matter volume and income (R = 0.14, P = 0.02). Surprisingly, this relationship was not present in patients with schizophrenia (R = −0.076, P = 0.17). Voxel-level analysis confirmed that this interaction was widespread across the cortex. After adjusting for global brain changes, income was positively related to prefrontal cortex volumes only in controls. Conversely, the hippocampus in patients with schizophrenia, but not in controls, was relatively larger in affluent environments. There was no significant correlation between environmental violence and brain structure.

Our results highlight the interplay between environment, particularly poverty, and individual characteristics in psychosis. This is particularly important for harsh environments such as low- and middle-income countries, where potentially less brain vulnerability (less grey matter loss) is sufficient to become unwell in adverse (poor) environments.

Psychotropics are overprescribed for adults with intellectual disabilities; there are few studies in children and young people.

To investigate antipsychotic and antidepressant prescribing in children and young people with and without intellectual disabilities, and prescribing trends.

Scotland's annual Pupil Census, which identifies pupils with and without intellectual disabilities, was record-linked to the Prescribing Information System. Antidepressant and antipsychotic data were extracted. Logistic regression was used to analyse prescribing between 2010 and 2013.

Of the 704 297 pupils, 16 142 (2.29%) had a record of intellectual disabilities. Antipsychotic and antidepressant use increased over time, and was higher in older pupils; antipsychotic use was higher in boys, and antidepressant use was higher in girls. Overall, antipsychotics were prescribed to 281 (1.74%) pupils with intellectual disabilities and 802 (0.12%) without (adjusted odds ratio 16.85, 95% CI 15.29–18.56). The higher use among those with intellectual disabilities fell each year (adjusted odds ratio 20.19 in 2010 v. 14.24 in 2013). Overall, 191 (1.18%) pupils with intellectual disabilities and 4561 (0.66%) without were prescribed antidepressants (adjusted odds ratio 2.28, 95% CI 2.03–2.56). The difference decreased each year (adjusted odds ratio 3.10 in 2010 v. 2.02 in 2013).

Significantly more pupils with intellectual disabilities are prescribed antipsychotics and antidepressants than are other pupils. Prescribing overall increased over time, but less so for pupils with intellectual disabilities; either they are not receiving the same treatment advances as other pupils, or possible overprescribing in the past is changing. More longitudinal data are required.