title: Increasing supplemental thyroid hormone use among premature infants born at 23 to 32 weeks' gestation.
abstract: We assessed the pattern of levo-thyroxine (l-thyroxine) therapy in very premature newborns over a 10-year period. We analyzed the electronic database of a large private neonatal practice group (Pediatrix, Ft. Lauderdale, FL) for 23- to 32-week gestation neonates ( N = 96,813) managed during 1997 to 2006. L-thyroxine use was analyzed by birth year and by gestational age (GA). L-thyroxine use increased with decreasing GA (nadir 0.3% at 32 weeks, peak 8.4% at 24 weeks). L-thyroxine supplementation increased 2.6-fold over time among infants ≤26 weeks' GA (3.4% in 1997 to 1999 to 8.7% in 2004 to 2006), but did not change among infants born at ≥29 weeks' GA. The highest rate of l-thyroxine supplementation (12.8%) occurred among 24-week GA infants in 2006. Median age at start of l-thyroxine was 23 days (25 to 75%, 15 to 38 days). Only 2% of treated infants were started on day of life 1. Despite no clear evidence from randomized trials supporting thyroid supplementation, l-thyroxine treatment of very preterm infants has significantly increased over the past decade. As l-thyroxine treatment was not consistent with protocols from published randomized trials, new focused randomized controlled trials are needed.
authors.affiliation: Department of Pediatrics, University of Utah, Salt Lake City, Utah 84158-1289, USA.
authors.forename: Megan
authors.initials: M
authors.lastname: Linn
authors.forename: Bradley A
authors.initials: BA
authors.lastname: Yoder
authors.forename: Reese H
authors.initials: RH
authors.lastname: Clark
mesh_terms: D002648:Child; D002675:Child, Preschool; D003409:Congenital Hypothyroidism / Q000097:blood / Q000150:complications / Q000453:epidemiology / Q000628:therapy; D002658:Developmental Disabilities / Q000097:blood / Q000453:epidemiology / Q000628:therapy; D020249:Hormone Replacement Therapy; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007234:Infant, Premature; D009422:Nervous System Diseases / Q000209:etiology / Q000517:prevention & control; D016032:Randomized Controlled Trials as Topic; D012189:Retrospective Studies; D013974:Thyroxine / Q000627:therapeutic use
chemical_list: D013974:Thyroxine