Preterm Birth Tied to Lasting Venous Thromboembolism Risk
Increased risk seen in infancy, early childhood, young adulthood; risks persist after adjustment
TUESDAY, July 29, 2014 (HealthDay News) -- Preterm birth is associated with increased long-term risk of venous thromboembolism (VTE), according to a study published online July 28 in Pediatrics.
Bengt Zöller, M.D., Ph.D., from Lund University in Malmö, Sweden, and colleagues examined long-term preterm birth-associated VTE risk. Data were obtained for a national cohort of 3,571,574 individuals who were live born in Sweden from 1973 through 2008 and followed up to 2010. Of these, 206,844 were born preterm (gestational age, <37 weeks).
The researchers observed an association between low gestational age at birth and VTE in infancy (age younger than 1 year; adjusted hazard ratios, 47.16 for 22 to 27 weeks; 5.54 for 28 to 33 weeks; 3.54 for 34 to 36 weeks, compared with 1.00 for 37 to 41 weeks). Low gestational age was also associated with increased risks of VTE in early childhood (ages 1 to 5 years) and young adulthood (age 18 to 38 years: adjusted hazard ratios, 2.76 for 22 to 27 weeks; 1.53 for 28 to 33 weeks; and 1.24 for 34 to 36 weeks, compared with 1.00 for 37 to 41 weeks). This association was not seen in late childhood (ages 6 to 12 years). There was an association for very preterm (before 34 weeks) but not late preterm birth (34 to 36 weeks) with VTE in adolescence. These correlations were attenuated after further adjustment for comorbidities, but most remained significant.
"In this large national cohort, low gestational age at birth was associated with increased risk of VTE in infancy, early childhood, and young adulthood," the authors write.