The Role of Food Sensitivity in Psoriasis

The Role of Food Sensitivity in Psoriasis: a 12-week Prospective Correlational Study of the Impact of an Individualized Elimination Diet on Disease Severity

Psoriasis is a common chronic skin disorder that affects over 4 million people. There is no cure for psoriasis and treatment is directed at controlling patients' symptoms. The purpose of this study is to determine whether psoriasis patients are more likely to have food sensitivities than those patients without psoriasis. We will also determine if eliminating certain foods from the diet results in a change in psoriasis symptoms.

Study Overview

• Status: Completed
• Conditions: Psoriasis
• Intervention / Treatment: Other: 12-week elimination diet

Detailed Description

Purpose: To determine the role of food sensitivity in psoriasis and assess the clinical response of an individualized elimination diet on psoriasis.

Design: Up to 50 volunteers with psoriasis and 20 age- and sex-matched controls will be recruited for a 12-week prospective correlational study.

Methods: Venous blood samples for the detection of antibodies against food antigens will be collected and individualized elimination diets will be designed based on the most reactive food antigens.

Assessments: Clinical assessments of objective and subjective parameters will be measured using Psoriasis Area and Severity Index (PASI), Static Physicians Global Assessment (sPGA), Dermatology Life Quality Index (DLQI), and Itch Numeric Rating Scale (Itch NRS).

Objectives: The primary objectives are to determine whether psoriasis patients are more likely to have food sensitivities and assess the clinical response of a 12-week elimination diet on psoriasis.

• Study Type: Interventional
• Enrollment (Actual): 51
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • Michigan
    • Ann Arbor, Michigan, United States, 48109
      • University of Michigan Department of Dermatology

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 8 years and older (Child, Adult, Older Adult)
• Accepts Healthy Volunteers: Yes

Description

Inclusion criteria:

• Male or female subjects, 12 years of age or older.
• Good general health.
• Willingness and ability to follow the protocol.
• Signed Informed Consent Form, written and witnessed.
• Psoriatic group only: Chronic plaque psoriasis (patients must have diagnosis for at least 6 months) or guttate psoriasis involving 2 % or greater total body surface area or 2 plaques, each measuring > 8 cm2.
• Psoriatic group only: Psoriasis is untreated (as defined in Exclusion criteria 4) or subject has been on a stable topical or systemic treatment with no dose alteration or regimen alteration for >12 months.

Exclusion criteria:

• History of drug-induced psoriasis or pustular psoriasis.
• Moderate or severe psoriasis warranting systemic immunosuppression or inpatient admission.
• Pregnant, lactating, history of diabetes mellitus, thyroid disease or inflammatory bowel disease.
• Psoriatic group only: Use of biologic treatment for psoriasis within 3 months of baseline, use of systemic immunosuppressive treatment for psoriasis within 4 weeks of baseline, or use of topical treatment for psoriasis within 2 weeks.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Other
• Allocation: Non-Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Psoriasis; Psoriasis patients will be placed on an individualized 12-week elimination diet	Other: 12-week elimination diet; individualized 12-week elimination diet based on the 4 most reactive foods +/- a gluten-free diet if there is detection of positive anti- tissue transglutaminase (tTG) IgG and IgA and anti-deamidated gliadin peptide (DGP) IgG and IgA
No Intervention: Healthy Control; Healthy Control patients will receive no intervention

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
IgG4 Antibodies	IgG4 Antibodies against Eliminated Food Antigens in Psoriasis Patients vs. Controls	12 weeks
IgE Antibodies	IgE Antibodies against Eliminated Food Antigens in Psoriasis Patients vs. Controls	12 weeks
Anti-Tissue Transglutaminase (tTG) IgG	Anti-Tissue Transglutaminase (tTG) IgG Change from Baseline in Psoriasis Patients vs. Controls	12 weeks
Anti-Tissue Transglutaminase (tTG) IgA	Anti-Tissue Transglutaminase (tTG) IgA Change from Baseline in Psoriasis Patients vs. Controls	12 weeks
Anti-Deamidated Gliadin Peptide (DGP) IgG	Anti-Deamidated Gliadin Peptide (DGP) IgG Change from Baseline in Psoriasis Patients vs. Controls	12 weeks
Anti-Deamidated Gliadin Peptide (DGP) IgA	Anti-Deamidated Gliadin Peptide (DGP) IgA Change from Baseline in Psoriasis Patients vs. Controls	12 weeks

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
IgG4 Antibodies in Subset	IgG4 Antibodies against Eliminated Food Antigens in Subset of Psoriasis Patients with positive test result who participated in dietary elimination intervention	12 weeks
IgE Antibodies in Subset	IgE Antibodies against Eliminated Food Antigens in Subset of Psoriasis Patients with positive test result who participated in dietary elimination intervention	12 weeks
Anti-Tissue Transglutaminase (tTG) IgG in Subset	Anti-Tissue Transglutaminase (tTG) IgG in Subset of Psoriasis Patients with positive test result who participated in dietary elimination intervention	12 weeks
Anti-Tissue Transglutaminase (tTG) IgA in Subset	Anti-Tissue Transglutaminase (tTG) IgA in Subset of Psoriasis Patients with positive test result who participated in dietary elimination intervention	12 weeks
Anti-Deamidated Gliadin Peptide (DGP) IgG in Subset	Anti-Deamidated Gliadin Peptide (DGP) IgG in Subset of Psoriasis Patients with positive test result who participated in dietary elimination intervention	12 weeks
Anti-Deamidated Gliadin Peptide (DGP) IgA in Subset	Anti-Deamidated Gliadin Peptide (DGP) IgA in Subset of Psoriasis Patients with positive test result who participated in dietary elimination intervention	12 weeks

Collaborators and Investigators

• Sponsor: University of Michigan
• Investigators: Principal Investigator: Yolanda Helfrich, MD, University of Michigan

Study record dates

Study Major Dates

• Study Start (Actual): August 28, 2017
• Primary Completion (Actual): October 22, 2023
• Study Completion (Actual): October 22, 2023

Study Registration Dates

• First Submitted: February 23, 2017
• First Submitted That Met QC Criteria: March 13, 2017
• First Posted (Actual): March 20, 2017

Study Record Updates

• Last Update Posted (Actual): May 8, 2024
• Last Update Submitted That Met QC Criteria: May 6, 2024
• Last Verified: May 1, 2024

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Skin Diseases; Skin Diseases, Papulosquamous; Psoriasis
• Other Study ID Numbers: Derm 685/HUM00115672

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

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