High Incidence and Recall Rate of Congenital Hypothyroidism in Zanjan Province, a Health Problem or a Study Challenge?

authors:

avatar Majid Valizadeh 1 , avatar Saeideh Mazloomzadeh 1 , avatar Ali Niksirat 1 , avatar Zahra Shajari ORCID 2 , *

Department of Internal Medicine, Faculty of Medicine, Zanjan University of Medical Sciences, IR Iran
Zanjan Metabolic Disease Research Center, Zanjan University of Medical Sciences, adz.shajari@gmail.com, IR Iran
International Journal of Endocrinology and Metabolism: Vol.9, issue 4; 338-342
article type: Original Article
received: May 3, 2011
accepted: July 30, 2011
DOI: https://doi.org/10.5812/Kowsar.1726913X.3639

how to cite: Valizadeh M, Mazloomzadeh S, Niksirat A, Shajari Z. High Incidence and Recall Rate of Congenital Hypothyroidism in Zanjan Province, a Health Problem or a Study Challenge?. Int J Endocrinol Metab. 2011;9(4): 338-342. https://doi.org/10.5812/Kowsar.1726913X.3639.

Abstract

Background: In Iran, congenital hypothyroidism (CH) screening programs to prevent mental retardation have been started recently. In this national program, all neonates with thyroid-stimulating hormone (TSH) level ≥ 5mIU/L are required to be recalled for a confirmatory test (venous sampling).
Objectives: This study was designed to investigate the incidence of CH and the patient recall rate on the basis of the above mentioned cutoff value for TSH and to compare the results with those obtained in other studies.
Patients and Methods: According to the screening protocol for CH, we assessed neonates born from February 2007 to January 2008 and registered details on the birth date, sex, birth weight, maternal gestational age, and parental consanguinity. TSH was measured from heel-prick blood samples obtained from neonates aged between 3 and 7 days. Neonates showing a TSH level of ≥ 5mIU/L were recalled for undergoing confirmatory tests.
Results: Among 18008 neonates screened for CH, 730 (4.1%) were recalled (TSH, ≥ 5mIU/L). Out of the recalled neonates, 96% were full-term neonates with a mean age of 5.0 ± 3.2 days and a mean TSH level of 8.6 ± 11.4mIU/L. CH was detected in 20 (2.7%) recalled neonates (incidence ratio of 1 in 895 live births) and subclinical hypothyroidism in 45 (6.1%) recalled neonates (incidence ratio of 1 in 398 live births).
Conclusions: Investigations have shown that Asian and Iranian neonates show a high CH prevalence. The recall rate in our study on the basis of the TSH cutoff value of more than 5mIU/L was higher (4%) than that in other studies. Therefore, in addition to emphasizing the importance of neonatal screening, we suggest that the cutoff level of TSH in the national screening program be reassessed and revised to reduce the recall rate for neonates.

  • Implication for health policy/practice/research/medical education:
    High incidence of congenital hypothyroidism and the recall rate was up to us to arrange a study in our area.While reviewing these data, the possible causes ranging from populaation issues to the sampling and measurment method etc were reviewed once.
  • Please cite this paper as:
    Valizadeh M, Mazlomzadeh S, Nicsirat A, Shajari Z. High Incidence and Recall Rate of Congenital Hypothyroidism in Zanjan Province, a Health Problem or a Study Challenge? Int J Endocrinol Metab. 2011;9(4):338-42. DOI: 10.5812/Kowsar.1726913X.3639

Copyright  © 2012 Kowsar M. P. Co. All rights reserved.

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