Perinatal and early life factors associated with symptoms of depression in Brazilian children

Background: Few studies have been conducted on the association between perinatal and early life factors with childhood depression and results are conflicting. Our aim was to estimate the prevalence and perinatal and early life factors associated with symptoms of depression in children aged 7 to 11 years from two Brazilian birth cohorts. Methods: The study was conducted on 1444 children whose data were collected at birth and at school age, in 1994 and 2004/2005 in Ribeirao Preto, where they were aged 10-11 years and in 1997/98 and 2005/06 in Sao Luis, where children were aged 7-9 years. Depressive symptoms were investigated with the Child Depression Inventory (CDI), categorized as yes (score >= 20) and no (score < 20). Adjusted and non-adjusted prevalence ratios (PR) were estimated by Poisson regression with robust estimation of the standard errors. Results: The prevalence of depressive symptoms was 3.9% (95% CI = 2.5-5.4) in Ribeirao Preto and 13.7% (95% CI = 11.0-16.4) in Sao Luis. In the adjusted analysis, in Ribeirao Preto, low birth weight (PR = 3.98; 95% CI = 1.72-9.23), skilled and semi-skilled manual occupation (PR = 5.30; 95% CI = 1.14-24.76) and unskilled manual occupation and unemployment (PR = 6.65; 95% CI = 1.16-38.03) of the household head were risk factors for depressive symptoms. In Sao Luis, maternal schooling of 0-4 years (PR = 2.39; 95% CI = 1.31-4.34) and of 5 to 8 years (PR = 1.80; 95% CI = 1.08-3.01), and paternal age < 20 years (PR = 1.92; 95% CI = 1.02-3.61), were independent risk factors for depressive symptoms. Conclusions: The prevalence of depressive symptoms was much higher in the less developed city, Sao Luis, than in the more developed city, Ribeirao Preto, and than those reported in several international studies. Low socioeconomic level was associated with depressive symptoms in both cohorts. Low paternal age was a risk factor for depressive symptoms in the less developed city, Sao Luis, whereas low birth weight was a risk factor for depressive symptoms in the more developed city, Ribeirao Preto.

CNPq (Conselho Nacional de Desenvolvimento Cientifico e Tecnologico - Brazilian National Research Council) [523474/96-2, 520664/98-1]

FAPEMA (Fundacao de Amparo a Pesquisa e ao Desenvolvimento Cientifico e Tecnologico do Maranhao)

FAPESP (Fundacao de Amparo a Pesquisa do Estado de Sao Paulo - Sao Paulo Research Foundation) [93/0525-0, 97/09517-1, 00/0908-7]