Transient Hypothyroidism at 3-Year Follow-Up among Cases of Congenital Hypothyroidism Detected by Newborn Screening

Abstract

Objective To investigate the rate of transient thyroid deficiency and treatment compliance among cases with congenital hypothyroidism diagnosed and followed-up after age 3 years by newborn screening (NBS). Study design Cases detected by Michigan NBS between October 1, 2003, and December 31, 2007, and followed-up after age 3 years were included. The X2 and Fisher exact tests were used to test differences among followed and lost cases. Logistic regression models were used to investigate predictors of treatment cessation. Results Roughly 45% of eligible cases were lost to follow-up, and disease state (transient or permanent congenital hypothyroidism) could not be determined for 12 cases (7.9%). Of the 72 followed cases, 34 (47%) were considered permanent congenital hypothyroidism based on thyroid imaging findings (n = 7) or an increase in medication dosage over time (n = 27). One-quarter of followed cases with congenital hypothyroidism were no longer being treated, and of these, just over 83% stopped treatment without medical supervision. Of 23 cases that underwent a medically supervised trial without thyroid hormone medication, treatment was reinstated in 20. Laboratory confirmation of euthyroidism was available for 6 of 18 cases clinically deemed transient. After adjustment, black race was the strongest predictor of treatment cessation (OR, 9.86; 95% CI, 1.82–53.31). Treatment cessation was also more common among low birth weight infants and those admitted to the neonatal intensive care unit at birth. Conclusion We recommend that NBS programs include long-term follow-up through at least age 3 years to determine treatment compliance and disease permanence. Further research is needed to determine ideal follow-up program operations and reassessment methods for congenital hypothyroidism disease permanence. Guidelines that provide evidence-based reassessment methods would be beneficial for the healthcare providers of children with congenital hypothyroidism.

Evolution to permanent or transient conditions in children with positive neonatal TSH screening tests in Sergipe, Brazil

“…Our rate of evolution to a permanent condition (86.5%) in the children diagnosed with initial CH is similar to that of the state of Michigan (USA), in which 75% of the diagnosed children progressed to permanent CH (16). In Paris, an analysis of 79 children with milder cases of CH and in-situ thyroid with less strict diagnostic criteria than ours (transient CH, TSH less than 6 µU/mL after cessation of treatment for at least 4 weeks and permanent CH, TSH greater than 7 µU/mL) revealed permanent CH in 62% and transient CH in 38% of the children (17).…”

“…If we take into account loss of follow-up in general, including cases with a completed final diagnosis, this figure rises to 38.0%, similar to two different reports (44.7% and 38.0%) from the USA. These problems are linked to financial constraints and other barriers (16,29). In addition, few screening programs followup routinely detected cases beyond the diagnosis.…”

Hipotireoidismo congênito: recomendações do Departamento de Tireoide da Sociedade Brasileira de Endocrinologia e Metabologia

“…If slightly elevated TSH persists during the first month of life, even with T 4 in the normal range, some researchers suggest treatment and re-evaluation at 3 years of age (19,43) (B,D).…”

Congenital Hypothyroidism 3-Year Follow-Up Project: Region 4 Midwest Genetics Collaborative Results

“…Initial presentation and rise in TSH levels during infancy were the two most common reasons provided for this decision. Previous reports have raised concerns over parental non-compliance, including discontinuation of thyroid medication without clinician supervision, as a significant issue in children managed for CH [6]. In our sample, we had one clinician report parental non-compliance and three children were lost to follow-up.…”

“…Made up of pediatric endocrinologists, state laboratory personnel, public health follow-up specialists, and parents of children with CH, the CH Workgroup sought to identify management and education patterns of pediatric endocrinologists and primary care providers for children diagnosed with CH by state NBS within the region. In light of reports that some children with CH were discontinuing thyroid hormone replacement without appropriate medical advice and were being lost to follow-up, the CH Workgroup specifically sought to identify management practices for re-evaluating the diagnosis of CH at or before three years of age [5,6].…”