Objective:

Mental illness is an important public health concern, often starting early in life and particularly impacting children from low-and middle-income countries. Our aims were to 1) determine, in a representative sample of public preschool 4- to 5-year old children in Brazil, the prevalence of internalizing and externalizing disorders and socioemotional development delays; and 2) to identify modifiable risk factors associated with mental, behavioral, or developmental disorders (MBDD), such as microsystem (i.e., parent-child relationship), mesosystem (social support), and macrosystem contextual factors (neighborhood disadvantage).

Methods:

A random sample of public preschool children was recruited in the city of Embu das Artes (São Paulo metropolitan area) (n=1,292 from 30 public preschools). Six-month prevalence of MBDD was measured using the Child Behavior Checklist (CBCL) and the Ages and Stages Questionnaires: Social-Emotional (ASQ:SE).

Results:

Six-month prevalence estimates were 25.4% for internalizing disorders, 12.1% for externalizing disorders, and 30.3% for socioemotional development delays. MBDD prevalence estimates were higher in families with stressful relationships and parental depression or anxiety, and in families with lower social capital.

Conclusion:

At least 25% of preschool children living in an urban area in Brazil presented a mental health disorder. These mental disorder were associated with modifiable factors such as stressful family relationships and lower social capital. Prevention and intervention measures such as family therapy are needed to decrease such high prevalence.