Perinatal factors and the risk of asthma in childhood--a population-based register study in Finland.
The aim of the study was to assess whether perinatal factors are associated with the risk of asthma in childhood in a register-based, nested case-control study in Finland. All children born between January 1, 1996, and April 30, 2004, who were entitled to a special reimbursement for antiasthmatic drugs (i.e., had diagnosed asthma by 2006 and had purchased inhaled corticosteroids or montelukast at least once), were identified (n = 21,038). For each case, one matched control child was selected. The associations between perinatal factors, derived from the Finnish Medical Birth Register, and the risk of asthma were analyzed by conditional logistic regression. In the final multivariate model, maternal asthma, young age, smoking, previous miscarriages, and a high number of previous deliveries, as well as cesarean section, low gestational age, and low ponderal index, were associated with an increased risk of asthma in children diagnosed before the age of 3 years. Among children diagnosed at the age of 3 years or later, maternal asthma, low gestational age, and low ponderal index were associated with an increased risk, and a high number of previous deliveries was associated with a decreased risk of asthma. In conclusion, perinatal factors play a role in the development of asthma in childhood, but the etiology may differ in early and late-onset asthma.
Department of Health Promotion and Chronic Disease Prevention, National Public Health Institute, Helsinki, Finland. johanna.metsala@ktl.fi
Johanna
J
Metsälä
Annamari
A
Kilkkinen
Minna
M
Kaila
Heli
H
Tapanainen
Timo
T
Klaukka
Mika
M
Gissler
Suvi M
SM
Virtanen
D000328:Adult; D018927:Anti-Asthmatic Agents / Q000627:therapeutic use; D001034:Apgar Score; D001249:Asthma / Q000453:epidemiology*; D001724:Birth Weight; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D036861:Delivery, Obstetric / Q000379:methods; D005260:Female; D005387:Finland / Q000453:epidemiology; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007234:Infant, Premature; D007236:Infant, Small for Gestational Age; D008297:Male; D008423:Maternal Age; D015999:Multivariate Analysis; D010298:Parity; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects; D012307:Risk Factors; D012907:Smoking / Q000009:adverse effects; D018709:Statistics, Nonparametric
D018927:Anti-Asthmatic Agents