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Trial registered on ANZCTR


Registration number
ACTRN12612000497808
Ethics application status
Approved
Date submitted
8/05/2012
Date registered
8/05/2012
Date last updated
8/05/2012
Type of registration
Retrospectively registered

Titles & IDs
Public title
Efficacy of vitamin A and zinc supplementation on pathogen-specific diarrheal disease.
Scientific title
Are pathogen-specific diarrhoeal disease rates lower among young children who receive vitamin A and zinc supplements separately or in combination compared to children receiving a placebo
Secondary ID [1] 280449 0
Nil
Universal Trial Number (UTN)
U1111-1130-4765
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Paediatric diarrhoeal disease 286428 0
Condition category
Condition code
Infection 286679 286679 0 0
Studies of infection and infectious agents
Oral and Gastrointestinal 286683 286683 0 0
Other diseases of the mouth, teeth, oesophagus, digestive system including liver and colon
Inflammatory and Immune System 286684 286684 0 0
Normal development and function of the immune system

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Children were assigned to 1 of 4 groups: 1) a vitamin A group that received 20 000 IU retinol every 2 mo for children aged <1 y or 45 000 IU for children aged >1 y, 2) a group that received a daily dose equivalent to 20 mg elemental Zn as zinc methionine, 3) a group that received both the zinc supplement and the vitamin A supplement as above, and 4) a placebo group and followed for 12 months. The vitamin A, zinc, and vitamin A - zinc supplements were prepared by personnel at the National Institute of Nutrition in 5-mL solutions that contained the supplements were similar in taste and appearance. Children in the placebo or control (sham) group received the same solution without any supplement. These solutions were packaged in consecutively numbered, color-coded, opaque plastic droplet bottles. During the 12-mo follow-up period, field personnel administered the solution containing the respective supplements twice a week to all children in the 3 treatment arms and placebo group and left bottles for the remaining days of the week with instructions on how to administer the solution.
Intervention code [1] 284810 0
Treatment: Other
Intervention code [2] 284816 0
Prevention
Comparator / control treatment
Vitamin A & zinc supplementation/placebo.

Children in the placebo group received the same solution as children in the treatment arms but without any supplement.
Control group
Placebo

Outcomes
Primary outcome [1] 287077 0
Pathogen-specific diarrhoea

A stool sample was collected twice a month for healthy children, and up to 3 stool samples were collected during the week after a diarrheal episode. Stool samples were plated onto Salmonella-Shigella, MacConkey, and MacConkey-tellurite agars for the identification of Salmonella species, Shigella species, and E. coli. The presence of ova and parasites in stool were determined by the Kato-Katz technique, to identify gastrointestinal infections with Entamoeba histolytica, A lumbricoides and G. lamblia. Five lactose-fermenting colonies with a morphological appearance resembling that of E. coli (when present) were selected from the MacConkey agar plates and speciated biochemically. Diarrheagenic E. coli ( DEC) were characterized by a single multiplex technique that detects pathogenic genes for each type of DEC. The primary end points for the study were the prevalence and duration of infections with G. lamblia, E. histolytica, and diarrheagenic E. coli among children and the incidence and duration of the diarrhea and fever episodes associated with these infections. An infection with G. lamblia or E. histolytica was defined as a stool sample that was positive for the given parasite. Infection with any of the specific diarrheagenic E. coli was defined as any lactose-positive bacteria isolated from stool that had the pathogenic genes for the respective pathogens. Durations of pathogen infections were defined as encompassing the time between the first and last sequentially collected stool samples that were positive for the pathogen. A single positive stool sample was assigned a duration of 1 day.
Timepoint [1] 287077 0
One year after randomization
Primary outcome [2] 287087 0
Pathogen-associated diarrhoea and fever

Episodes of fever or diarrhea were defined as pathogen associated if the episode occurred within 7 days before or after a positive stool sample. A diarrheal episode was defined as the mother?s reporting of symptoms in the child and was confirmed by the passage of 3 or more liquid stools in 1 day. The duration of a diarrheal episode was defined as encompassing the sequential days of reported diarrheal symptoms in the child followed by 3 or more symptom-free days.
Timepoint [2] 287087 0
One year after randomization
Secondary outcome [1] 297332 0
Cytokine responses in stool

Stool samples were extracted by homogenization and centrifugation and then the supernatants were assayed for the proinflammatory cytokine IL-6, the Th1 cytokine IFN-g, and the Th2 cytokine IL-4 by an ELISA using paired ELISA specific capture and biotinylated detecting antibody. Peroxidases conjugated to steptavidin were used to detect the capture of Ab; peroxidase activity was measured using ABTS substrate and read at a wavelength of 405 nm. Recombinant cytokines were used to generate a standard curve, and levels of these cytokines from the stool extracts were determined using the standard curve in 96-well plates according to the manufacturer's protocol.
Timepoint [1] 297332 0
One year after randomization

Eligibility
Key inclusion criteria
Children 6-15 months of age living in peri-urban communities of Mexico City
Minimum age
6 Months
Maximum age
15 Months
Gender
Both males and females
Can healthy volunteers participate?
Yes
Key exclusion criteria
Children with immuno-suppression or any congenital or acquried alteration of the digestive tract that could alter the absorption of micronutrients were excluded. Children were also excluded when they had received a vitamin A supplement from a source outside the project.

Study design
Purpose of the study
Prevention
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Caretakers of children identified through a community census were invited to participate in the study. Assignment of children to treatment or placebo group carried out by project personnel at the Centre for Childhood and Adolescent Health within the Mexican Ministry of Health to assure that caretakers, field personnel and the Principla Inivestigator were blinded.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
The randomization sequence was generated using a random-number table by project personnel at the Centre for Childhood and Adolescent Health
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?



Intervention assignment
Parallel
Other design features
Phase
Not Applicable
Type of endpoint(s)
Efficacy
Statistical methods / analysis

Recruitment
Recruitment status
Completed
Date of first participant enrolment
Anticipated
Actual
Date of last participant enrolment
Anticipated
Actual
Date of last data collection
Anticipated
Actual
Sample size
Target
Accrual to date
Final
Recruitment outside Australia
Country [1] 4290 0
Mexico
State/province [1] 4290 0
Federal District (Mexico City)

Funding & Sponsors
Funding source category [1] 285210 0
Government body
Name [1] 285210 0
National Institute of Diabetes and Digestive and Kidney Diseases
Address [1] 285210 0
NIDDK, NIH
Bldg 31, Rm 9A06
31 Center Drive, MSC 2560
Bethesda, MD 20892-2560
USA
Country [1] 285210 0
United States of America
Primary sponsor type
University
Name
University of Queensland
Address
Brisbane St Lucia, QLD 4072
Country
Australia
Secondary sponsor category [1] 284082 0
None
Name [1] 284082 0
Address [1] 284082 0
Country [1] 284082 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 287215 0
Medical Research Ethics Committee
Ethics committee address [1] 287215 0
Research & Training Division
Cumbrae-Stewart Building
University of Queensland
The University of Queensland
Brisbane QLD 4072
Ethics committee country [1] 287215 0
Australia
Date submitted for ethics approval [1] 287215 0
Approval date [1] 287215 0
19/06/2008
Ethics approval number [1] 287215 0
2008000895

Summary
Brief summary
The project is evaluating the impact of vitamin A and zinc supplementation on the on the epidemiology and clinical history of bacterial, parasitic and viral diarrheal pathogen infections among children living in marginalized communities of Mexico City. The study hypothesis is that these two micronutrient supplements will have distinct and contrasting effects on pathogen infections compared to children in the placebo group. The project was randomized, double-blind, placebo-controlled trial that was carried out among 800 children 6-15 mo. of age in peri-urban areas of Mexico City from 2000 to 2003. Enrolled children were assigned to either a group receiving vitamin A every two months, a group receiving a daily zinc supplement, a group receiving both the zinc and vitamin A supplements, or a placebo group. Stools collected once a month and following diarrheal episodes from children in the 12 month follow-up are being screened for diarrheal E. coli, enteric viral pathogens and helminthes and gut protozoa. Pathogen-specific diarrhoeal rates among children in the different treatment arms and placebo group are now being compared in the 707 children who remained in the study.
Trial website
Trial related presentations / publications
PUBLICATIONS

Long KZ, Garcia C, Ko GP, Santos JI, Mamun AA, Rosado JL, DuPont HL, Nathakumar N. Vitamin A modifies the intestinal chemokine and cytokine responses to Norovirus (NoV) infection in Mexican children. J Nutr 2011; 141 957-963.

Long KZ, Santos JI, Rosado JL, Estrada T, Haas M, Firestone M, DuPont HL, Nanthakumar N. Vitamin A supplementation modifies the association between mucosal innate and adaptive immune responses and enteric pathogen-specific outcomes. Am J Clin Nutr 2011; 93 578-585.

Long KZ, Rosado JL, Santos JI, Haas M, Al Mamun A, DuPont HL, Nanthakumar N, Estrada T. Associations between mucosal innate and adaptive immune responses and resolution of diarrheal pathogen infections. Infect Immun 2010;78:1221–1228.

Rosado JL, Caamaño MC, Montoya YA, de Lourdes Solano M, Santos JI, Long KZ. Interaction of zinc or vitamin A supplementation and specific parasite infections on Mexican infants' growth: a randomized clinical trial. Eur J Clin Nutr. 2009; 63:1176–1184.

Estrada-Garcia T, Lopez-Saucedo C, Thompson-Bonilla R, Abonce M, Lopez-Hernandez D, Santos JI, Rosado JL, DuPont HL, Long KZ. Association of diarrheagenic Escherichia coli Pathotypes with infection and diarrhea among Mexican children and association of atypical Enteropathogenic E. coli with acute diarrhea. J Clin Microbiol. 2009;47:93-8.

Long KZ, Rosado JL, Montoya Y, Solano ML, Hertzmark E and Santos JI. Impact of vitamin A and zinc supplementation on G. lamblia, E. histolytica, and A. lumbricoides infections among Mexican children in a randomized clinical trial. Pediatrics. 2007 120; e846-e855.

Long KZ, García C, Santos JI, Rosado JL, Hertzmark E, DuPont HL, Ko GP. Vitamin A Supplementation has divergent effects on Norovirus Infections and Clinical Symptoms among Mexican Children. J Infect Dis 2007;196:978-985.

Long KZ, Rosado JL and Fawzi W. The comparative impact of iron, the B complex vitamins, vitamins C and E and selenium on diarrheal pathogen outcomes relative to the impact produced by vitamin A and zinc. Nutrition Rev 2007;65:218-232

Long KZ, Santos JI, Fawzi W, DuPont HL, Hertzmark E, Rosado JL. Supplementation with vitamin A reduces watery diarrhea and respiratory infections in Mexican Children.
Br J Nutr 2007;97:337-343.

Long KZ, Santos JI, Rosado JL, Lopez-Saucedo C, Thompson-Bonillo R, Abonce M, DuPont HL, Hertzmark E, Estrada T. Impact of Vitamin A on selected gastrointestinal pathogen infections and associated diarrheal episodes among children in Mexico City, Mexico. J Infect Dis 2006;194:1217-1225.

Long KZ, Santos JI, Estrada T, Haas M, Firestone M, Bhagwat J, DuPont HL, Rosado JL, Hertzmark E, , and Nanthakumar N. Vitamin A supplementation reduces the monocyte chemoattractant protein-1 intestinal immune response of Mexican children, J Nutr 2006;136: 2600-2605.

García C, DuPont HL, Long KZ, Santos JI, Ko GP. Asymptomatic Excretion and Genetic Diversity of Noroviruses in Mexican Children. J Clinical Micro 2006; 44: 2997-3000.

Long KZ, Estrada T, Santos JI, Haas M, Rosado JL, Firestone M, Bhagwat J, Young C, DuPont HL, Hertzmark E, and Nanthakumar N. The impact of vitamin A supplementation on the intestinal immune response in Mexican children is modified by pathogen infections and diarrhea. J Nutr 2006; 136:1365-70.

Long KZ, Montoya Y, Hertzmark E, Santos JI, Rosado JL. A double-blind randomized clinical trial of the impact of vitamin A and zinc supplementation on diarrheal disease and respiratory tract infections among children in Mexico City, Mexico. Am J Clin Nutr 2006; 83:693-700.

Long KZ and Nanthakumar N. Energetic and nutritional regulation of the adaptive immune response and trade-offs in Ecological Immunology. Amer J Human Biol 2004; 16:499-50.


PAPERS PRESENTED AT TECHNICAL AND PROFESSIONAL MEETINGS:

Sanchez J, Rosado J, Caamano M, Marks G, Long KZ. Interactions of nutritional status with vitamin a or zinc supplementation on gastrointestinal parasite infections in Mexican children. Experimental Biology Meetings, Washington, DC 2011.

Long KZ, Rosado JL, Ko G. Effect of vitamin A supplementation on fecal cytokine levels following norovirus (NoV) infections in Mexican infants. International Congress of Nutrition, Bangkok, Thailand. 2009

Sanchez J, Rosado J, Caamano M, Marks G, Long KZ. Interactions of nutritional status with vitamin a or zinc supplementation on gastrointestinal parasite infections in Mexican children. International Congress of Nutrition, Bangkok, Thailand 2009.

Long KZ, Santos JI, Rosado JL, Estrada T, Haas M, Firestone M, DuPont HL, Nanthakumar N. Vitamin A supplementation modifies associations between intestinal immune responses and enteric pathogen infections among Mexican children. Experimental Biology Meetings, San Diego CA 2008.

Rosado JL, Caamaño MC, Montoya YA, Frongillo E, Santos JI, Long KZ. Impact of vitamin A and zinc supplementation on growth among Mexican children. Experimental Biology Meetings, San Franciso CA 2006.

Long KZ, Garcia C, Santos JI, Rosado JL, Hertzmark E, DuPont HL, Ko GP. Impact of vitamin A supplementation on norovirus infections and diarrhea in Mexican children. Experimental Biology Meetings, San Franciso CA 2006.

Long KZ, Rosado JL, Hertzmark E, Estrada T, DuPont HL, Santos JI. Impact of vitamin A on gastrointestinal pathogen infections and associated diarrheal disease episodes among children in Mexico City, Mexico. Poster. Experimental Biology Meetings, San Diego. 2005.

Long KZ, Rosado JL, Montoya Y, et al. Vitamin A and zinc have distinct effects on gastro-intestinal parasite infections among children in Mexico City, Mexico. Experimental Biology Meetings, Washington DC. 2004.

Long KZ, Haas M, Young C, et al. Impact of vitamin A on the intestinal immune response in pathogen induced diarrhea of children in Mexico City, Mexico. Experimental Biology Meetings, Washington DC. 2004.
Public notes

Contacts
Principal investigator
Name 34146 0
Address 34146 0
Country 34146 0
Phone 34146 0
Fax 34146 0
Email 34146 0
Contact person for public queries
Name 17393 0
Dr. Kurt Long
Address 17393 0
Nutrition and Environmental Health Unit
School of Population Health
University of Queensland
Herston Road
Herston QLD 4006
Country 17393 0
Australia
Phone 17393 0
61 7 3665 5404
Fax 17393 0
Email 17393 0
k.long@uq.edu.au
Contact person for scientific queries
Name 8321 0
Dr. Kurt Long
Address 8321 0
Nutrition and Environmental Health Unit
School of Population Health
University of Queensland
Herston Road
Herston QLD 4006
Country 8321 0
Australia
Phone 8321 0
61 7 3665 5404
Fax 8321 0
Email 8321 0
k.long@uq.edu.au

No information has been provided regarding IPD availability
Summary results
Have study results been published in a peer-reviewed journal?
Other publications
Have study results been made publicly available in another format?
Results – basic reporting
Results – plain English summary