VCSIP Follow-up Study (VCSIPRenewal)

Vitamin C to Decrease the Effects of Smoking in Pregnancy on Infant Lung Function (VCSIP): Follow-up of a Randomized Trial

The overall aims of this protocol are to determine whether prenatal supplementation with vitamin C to pregnant smokers can improve pulmonary function and decrease wheeze at 5 years of age in their offspring. This is a continuation of the VCSIP trial, to follow the offspring through 5 years of age. The hypothesis for this protocol is an extension of the VCSIP trial that supplemental vitamin C in pregnant smokers can significantly improve their children's PFTs and decrease the incidence of wheeze.

Study Overview

• Status: Completed
• Conditions: Asthma; Pulmonary Function; Wheezing; In Utero Nicotine
• Intervention / Treatment: Other: No active intervention

Detailed Description

The overall aims of this protocol are to determine whether prenatal supplementation with vitamin C to pregnant smokers can improve pulmonary function and decrease wheeze at 5 years of age in their offspring. This is a continuation of the VCSIP trial, to follow the offspring through 5 years of age. The hypothesis for this protocol is an extension of the VCSIP trial that supplemental vitamin C in pregnant smokers can significantly improve their children's PFTs and decrease the incidence of wheeze. The reasons for this protocol are to follow the children born to mothers randomized in the VCSIP to the age of 5 to differentiate the patients with transient versus recurrent wheeze (and therefore more likely to develop asthma); to determine if early protective effects of vitamin C are sustained to this older age; and to continue to collect biologic samples from the children for future mechanistic studies of vitamin C action.

The primary aim of this study is to demonstrate improved pulmonary function at 5 years of age in the offspring of pregnant smokers randomized to vitamin C (500 mg/day) versus placebo. The investigators hypothesize that vitamin C supplementation in pregnancy will block the adverse effects of maternal smoking on offspring pulmonary function measured at 5 years of age by spirometry. Impulse oscillometry (IOS) will also be used at 3-5 years of age to assess pulmonary function.

Specific Aim 2 (Secondary Outcome): The secondary aim of this study is to demonstrate a decreased incidence of wheeze at 5 years of age in offspring of pregnant smokers randomized to vitamin C (500 mg/day) versus placebo. The investigators hypothesize that vitamin C supplementation during pregnancy will decrease the incidence of wheeze at 5 years of age in offspring of smokers. Respiratory health will be assessed by quarterly validated respiratory questionnaires and clinician report.

• Study Type: Observational
• Enrollment (Actual): 242

Contacts and Locations

Study Locations

• United States
  • Indiana
    • Indianapolis, Indiana, United States, 46202-5167
      • Indiana University
  • Oregon
    • Portland, Oregon, United States, 97239
      • Oregon Health and Science University

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 6 months to 4 years (Child)
• Accepts Healthy Volunteers: N/A

• Sampling Method: Probability Sample

Study Population

This is a follow up of NCT01723696. In that study, pregnant smokers were recruited at obstetric clinics delivering at OHSU, PeaceHealth Southwest Washington Medical Center in Vancouver, Washington or Indiana University in Indianapolis, Indiana. We are now following the offspring of those pregnant smokers (and control group non-smokers).

Description

Inclusion Criteria:

• Women and their offspring randomized to vitamin C versus placebo during pregnancy as well as pregnant nonsmokers and their offspring enrolled as the reference group in the current RCT.

Exclusion Criteria:

• Patients specifically withdrawing consent.

Study Plan

How is the study designed?

Number of groups / cohorts

3

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Offspring of smokers who got vitamin C; Offspring of pregnant smokers randomized to vitamin C during the initial randomized portion of the VCSIP study	Other: No active intervention; This is a follow-up of a randomized trial. No active intervention is being given in the follow-up.
Offspring of smokers who got placebo; Offspring of pregnant smokers randomized to placebo during the initial randomized portion of the VCSIP study	Other: No active intervention; This is a follow-up of a randomized trial. No active intervention is being given in the follow-up.
Offspring of pregnant non-smokers; Offspring of pregnant non-smokers who were followed in a similar fashion during pregnancy as the randomized pregnant smokers	Other: No active intervention; This is a follow-up of a randomized trial. No active intervention is being given in the follow-up.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Improved pulmonary function, spirometry	The primary aim of this study is to demonstrate improved pulmonary function at 5 years of age in the offspring of pregnant smokers randomized to vitamin C 500 mg/day versus placebo.	5 years of age

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Decreased incidence of wheeze	The secondary aim of this study is to demonstrate a decreased incidence of wheeze at 5 year of age in offspring of pregnant smokers randomized to vitamin C (500 mg/day) versus placebo	5 years of age

Collaborators and Investigators

• Sponsor: Oregon Health and Science University
• Collaborators: National Institutes of Health (NIH); Indiana University
• Investigators: Principal Investigator: Cindy McEvoy, MD, MCR, Oregon Health and Science University

Publications and helpful links

General Publications

• McEvoy CT, Schilling D, Clay N, Jackson K, Go MD, Spitale P, Bunten C, Leiva M, Gonzales D, Hollister-Smith J, Durand M, Frei B, Buist AS, Peters D, Morris CD, Spindel ER. Vitamin C supplementation for pregnant smoking women and pulmonary function in their newborn infants: a randomized clinical trial. JAMA. 2014 May;311(20):2074-82. doi: 10.1001/jama.2014.5217.

Study record dates

Study Major Dates

• Study Start (Actual): March 27, 2017
• Primary Completion (Actual): December 31, 2021
• Study Completion (Actual): December 31, 2024

Study Registration Dates

• First Submitted: March 28, 2017
• First Submitted That Met QC Criteria: June 27, 2017
• First Posted (Actual): June 29, 2017

Study Record Updates

• Last Update Posted (Actual): March 25, 2025
• Last Update Submitted That Met QC Criteria: March 20, 2025
• Last Verified: March 1, 2025

More Information

Terms related to this study

• Keywords: asthma; antioxidants; pulmonary function testing; vitamin C; wheeze; forced expiratory flows
• Additional Relevant MeSH Terms: Signs and Symptoms, Respiratory; Respiratory Sounds
• Other Study ID Numbers: VCSIP-Renewal

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED

Drug and device information, study documents

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