Congenital heart diseases: population-based cross-sectional study and spatial analysis, São Paulo, 2012-2022.

Of 1,777,316 live births recorded in São Paulo between 2012 and 2022, 9,293 presented congenital heart diseases.

• Data were sourced from the Live Birth Information System (SINASC) for the municipality of São Paulo.
• Congenital heart diseases were classified using ICD-10 codes Q20-Q28.
• The comparison group consisted of all other live births without congenital heart disease diagnoses.
• Study design was a population-based cross-sectional study with ecological spatial analysis.

Spatial analysis identified a cluster of congenital heart disease cases in the northern area of São Paulo municipality.

• Spatial scan analysis was used to identify geographic clusters of risk.
• Residence in areas of spatial clustering was associated with significantly increased odds of congenital heart disease (OR 2.97; 95%CI 2.82; 3.12).
• The northern zone cluster represented the strongest single factor associated with congenital heart disease occurrence in the study.

Preterm pregnancy and multiple-order pregnancies were associated with increased odds of congenital heart disease.

• Preterm pregnancy was associated with OR 2.61 (95%CI 2.45; 2.78).
• Triple or higher-order pregnancy was associated with OR 2.60 (95%CI 1.57; 4.31).
• Twin pregnancies were associated with OR 1.14 (95%CI 1.00; 1.30).
• These obstetric factors were identified through logistic regression analysis.

Maternal sociodemographic characteristics including marital status, education level, age, and race/skin color were associated with congenital heart disease occurrence.

• Stable union (as opposed to other marital statuses) was associated with OR 1.44 (95%CI 1.37; 1.53).
• Maternal education of 1 to 7 years was associated with OR 1.26 (95%CI 1.14; 1.39), and 8 to 11 years with OR 1.20 (95%CI 1.11; 1.29).
• Maternal age between 35 to 49 years was associated with OR 1.19 (95%CI 1.11; 1.28).
• Asian race/skin color was associated with OR 1.81 (95%CI 1.47; 2.24) and Black race/skin color with OR 1.16 (95%CI 1.06; 1.27).
• Logistic regression was used to estimate odds ratios and 95% confidence intervals for all maternal factors.