Excessive crying at 3 months of age and behavioural problems at 4 years age: a prospective cohort study.
BACKGROUND
Excessive crying in early infancy has been associated with behavioural problems among preschool children from high income countries but studies in low income and middle income countries are scarce.


METHODS
The 2004 Pelotas Birth Cohort is a population-based study planned to enrol all live births occurring in Pelotas that year and comprises 4231 children who so far have been followed up at 3, 12, 24, 48 and 72 months of age. Several familial, maternal and child characteristics were gathered in every follow-up. At the 3-month follow-up, infants whose mothers perceived them as crying more than others of the same age were classified as 'crying babies'. Child behavioural problems were assessed through the Child Behavior Checklist (CBCL) applied to the mother at the 48-month follow-up. Crude and adjusted ORs with 95% CIs were calculated by logistic regression.


RESULTS
Prevalence of excessive crying at 3 months was 11.9% (10.9% to 13.0%). Among children with excessive crying at 3 months the proportion in the clinical range for CBCL total, internalising and externalising problems at 4 years of age was 31.2%, 12.9% and 37.5%, respectively, against 20.6%, 6.8% and 29.6%, respectively, among non-crying babies. After controlling for confounders crying babies presented increased risk of being in clinical range of CBCL total (OR=1.34; 1.03 to 1.74), internalising (OR=1.55; 1.09 to 2.21) and externalising problems (OR=1.29; 1.01 to 1.64) than infants without excessive crying.


CONCLUSIONS
Excessive crying in early infancy may represent one important risk factor for developing behavioural problems in later phases of early childhood.
['Santos|Iná S|IS|', 'Matijasevich|Alicia|A|', 'Capilheira|Marcelo F|MF|', 'Anselmi|Luciana|L|', 'Barros|Fernando C|FC|']
D000293:Adolescent D000328:Adult D001938:Brazil D002653:Child Behavior Disorders D002675:Child, Preschool D003448:Crying D004522:Educational Status D005260:Female D006801:Humans D007223:Infant D016015:Logistic Models D017533:Marital Status D008423:Maternal Age D009035:Mothers D011247:Pregnancy D011256:Pregnancy Outcome D015995:Prevalence D011446:Prospective Studies D012307:Risk Factors D055815:Young Adult
Cohort studies CHILD HEALTH EPIDEMIOLOGY PRIMARY HEALTH CARE PUBLIC HEALTH