Iodine Status: is there a public health issue on the Island of Ireland

• Research type

  Research Study

• Full title

  Iodine Status: is there a public health issue on the Island of Ireland -Neonatal blood spot thyroid stimulating hormone as a proxy measure of iodine status to determine the seasonality of iodine status and trends over the last 20 years in neonates on the island of Ireland.

• IRAS ID

  161970

• Contact name

  Jayne Woodside

• Contact email

  j.woodside@qub.ac.uk

• Duration of Study in the UK

  0 years, 10 months, 31 days

• Research summary

  The aim of this study is to use neonatal blood spot thyroid stimulating hormone (TSH) as a proxy (i.e. approximate representation) measure of iodine status to determine the seasonality of iodine status and trends over the last 20 years in neonates on the island of Ireland.
  
  The United Kingdom (UK) and Republic of Ireland (ROI) both have a national screening program – all newborn babies have a bloodspot TSH measured from a heel prick sample taken on day 2-8 after birth. Where an elevated (high) TSH level is found (>20 mIU/l), it is confirmed and thyroid hormone treatment is started within the first 18 days of life. Recently researchers in Dublin have found a trend towards increasing TSH within the normal range over several years alongside a decline of urinary iodine concentration among the pregnant population. They also found seasonality in neonatal TSH results taken in January versus August, which may reflect the seasonality of dietary iodine demonstrated in the UK. Other small studies give conflicting results and this area of iodine status and neonatal TSH requires clarification, as the season of birth could then be relevant to the nutritional advice given to mothers.

  We propose examining the possible seasonality of TSH in neonates throughout the island of Ireland and explore the trends of the neonatal TSH estimation over 20 years, during which time iodine intake is thought to have declined.

  Results will be examined anonymously for the last 20 years (a) to look for seasonality of results; (b) to explore the trends of the neonatal TSH estimation over 20 years and (c) to look at the frequency of congenital hypothyroidism over time and during different seasons.

• REC name

  South Central - Berkshire Research Ethics Committee

• REC reference

  14/SC/1331

• Date of REC Opinion

  15 Oct 2014

• REC opinion

  Favourable Opinion