Iodinated Contrast Agents and Risk of Hypothyroidism in Young Children in the United States

This study will estimate the incidence of hypothyroidism in a pediatric population of children under age 4, based on data from the US-based Kaiser Permanente Northern California database, which were exposed to iodinated contrast agent through having a diagnostic procedure.

Study Overview

• Status: Completed
• Conditions: Hypothyroidism
• Intervention / Treatment: Drug: Iodinated contrast agents

• Study Type: Observational
• Enrollment (Actual): 2320

Contacts and Locations

Study Locations

• United States
  • California
    • Oakland, California, United States, 94612
      • Oakland

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: No older than 3 years (Child)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

• Sampling Method: Non-Probability Sample

Study Population

Children under age 4 in the Kaiser Permanente Northern California database, who had a diagnostic procedure with an iodinated contrast agent

Description

Inclusion Criteria:

• Children under age 4 in the Kaiser Permanente Northern California (KPNC) database, who had a diagnostic procedure with an iodinated contrast agent.
• Participants should be member of the KPNC for at least 3 months before the iodinated contrast exposure, except where the child is under 3 months of age at time of initial exposure, and 2 weeks after the exposure.

Exclusion Criteria:

• Diagnosis of hypothyroid any time prior to the iodine contrast exposure.
• Lab values for low thyroid (TSH > 5 mU/L for children) any time before the exposure
• Thyroid replacement therapy, Hashimoto thyroiditis, or congenital hypothyroidism any time prior to exposure.

Study Plan

How is the study designed?

Design Details

• Observational Models: Cohort
• Time Perspectives: Retrospective

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Iodinated contrast agents; Children under age 4 in the Kaiser Permanente Northern California database, who had a diagnostic procedure with an iodinated contrast agent	Drug: Iodinated contrast agents; Use of iodine contrast agents and doses following the decision of the treating physician.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Incidence Rate of Hypothyroidism Detected in Routine Clinical Practice	Incidence density rates (IDR) were calculated as the number of cases over the person time at risk where the numerator was the number of cases and the denominator was the person years at risk.	In the 365 days post exposure to an iodinated contrast agent

Secondary Outcome Measures

Outcome Measure	Time Frame
Baseline Characteristics (Age) of the Cases With Hypothyroidism and of the Rest of the Cohort	Up to 365 days after a diagnostic scan with iodinated contrast agent
Baseline Characteristics (Sex) of the Cases With Hypothyroidism and of the Rest of the Cohort	Up to 365 days after a diagnostic scan with iodinated contrast agent
Baseline Characteristics (Year of Hypothyroidism Diagnosis) of the Cases With Hypothyroidism and of the Rest of the Cohort	Up to 365 days after a diagnostic scan with iodinated contrast agent
Baseline Characteristics (Type of Iodine Contrast Exposure) of the Cases With Hypothyroidism and of the Rest of the Cohort	Up to 365 days after a diagnostic scan with iodinated contrast agent
Baseline Characteristics (Race/Ethnicity) of the Cases With Hypothyroidism and of the Rest of the Cohort	Up to 365 days after a diagnostic scan with iodinated contrast agent
Time From First Iodinated Contrast to First Hypothyroidism Event	Up to 365 days after a diagnostic scan with iodinated contrast agent
Classification of Subclinical/Manifest Hypothyroidism by Type of Exposure	Up to 365 days after a diagnostic scan with iodinated contrast agent
Classification of Hypothyroidism by Etiology	Up to 365 days after a diagnostic scan with iodinated contrast agent

Collaborators and Investigators

• Sponsor: Bayer

Study record dates

Study Major Dates

• Study Start (Actual): October 15, 2016
• Primary Completion (Actual): June 15, 2017
• Study Completion (Actual): June 15, 2017

Study Registration Dates

• First Submitted: October 11, 2016
• First Submitted That Met QC Criteria: November 7, 2016
• First Posted (Estimate): November 9, 2016

Study Record Updates

• Last Update Posted (Actual): January 30, 2019
• Last Update Submitted That Met QC Criteria: January 29, 2019
• Last Verified: January 1, 2019

More Information

Terms related to this study

• Keywords: database; Hypothyroidism,; children,; iodinated contrast agents,; retrospective cohort,
• Additional Relevant MeSH Terms: Endocrine System Diseases; Thyroid Diseases; Hypothyroidism
• Other Study ID Numbers: 19185

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No