N/A N=11,234 Randomized Triple-blind Supportive Care

Evaluation of a Letter Intervention Promoting a Plant-based Diet

Cardiovascular Diseases · Diabetes Mellitus · Obesity

Bottom Line

View on ClinicalTrials.gov: NCT03880838 ↗

Enrolled (actual)

11,234

Serious AEs

—

Results posted

Sep 2023

Primary outcome: Primary: Medical Cost in US Dollars From One Year Before to One Year After Intervention — 6123.39; 5863.82; 5901.99; 5630.26 dollars

Study Design & Population

Study type: Interventional
Phase: N/A
Interventions: Personal testimonial (Behavioral); Forks Over Knives Documentary (Behavioral); Commitment nudge (Behavioral); Prevention nudge (Behavioral)
Age: Adult, Older Adult · 18+ yrs
Sex: All
Sponsor: Geisinger Clinic
Primary completion: Jun 2020

Outcome Measures

Outcome	Result	p-value
PRIMARY Medical Cost in US Dollars From One Year Before to One Year After Intervention	6123.39; 5863.82; 5901.99; 5630.26; 6427.50; 6343.24	—
PRIMARY Number of Visits From One Year Before to One Year After Intervention	5.59; 5.57; 5.17; 5.66; 5.69; 5.77	—
PRIMARY Number of Prescriptions From One Year Before to One Year After Intervention	48.96; 48.02; 47.44; 50.85; 50.50; 49.66	—
PRIMARY Number of Unique Prescribed Medication From One Year Before to One Year After Intervention	8.12; 8.15; 7.90; 8.50; 8.47; 8.48	—
PRIMARY Body Mass Index From One Year Before to One Year After Intervention	36.44; 36.48; 36.46; 36.20; 37.26; 36.58	.391
PRIMARY Systolic Blood Pressure From One Year Before to One Year After Intervention	130.00; 129.88; 130.47; 131.4; 130.72; 129.27	.436
PRIMARY Diastolic Blood Pressure From One Year Before to One Year After Intervention	72.91; 72.79; 72.95; 73.48; 72.93; 72.27	.357
SECONDARY Triglyceride Levels From One Year Before to One Year After Intervention	—	—
SECONDARY Low-density Lipoprotein (LDL) Levels From One Year Before to One Year After Intervention	—	—
SECONDARY Five Years Before to Two Years After Intervention in Depressed Mood and Anhedonia as Assessed by the Patient Health Questionnaire-2 (PHQ-2) (Extended Time Frame)	—	—
SECONDARY Hemoglobin A1c (hbA1c) From Five Years Before to Two Years After Intervention (Extended Time Frame)	—	—
SECONDARY Low-density Lipoprotein/High-density Lipoprotein (LDL/HDL) Ratios From Five Years Before to Two Years After Intervention (Extended Time Frame)	—	—
SECONDARY High-density Lipoprotein (HDL) Levels From Five Years Before to Two Years After Intervention (Extended Time Frame)	—	—
SECONDARY Low-density Lipoprotein (LDL) Levels From Five Years Before to Two Years After Intervention (Extended Time Frame)	—	—
SECONDARY Triglyceride Levels From Five Years Before to Two Years After Intervention (Extended Time Frame)	—	—
SECONDARY Diastolic Blood Pressure From Five Years Before to Two Years After Intervention (Extended Time Frame)	—	—
SECONDARY Systolic Blood Pressure From Five Years Before to Two Years After Intervention (Extended Time Frame)	—	—
SECONDARY Body Mass Index From Five Years Before to Two Years After Intervention (Extended Time Frame)	—	—
SECONDARY Number of Unique Prescribed Medication From Five Years Before to Two Years After Intervention (Extended Time Frame)	—	—
SECONDARY Number of Prescriptions From Five Years Before to Two Years After Intervention (Extended Time Frame)	—	—
SECONDARY Number of Visits From Five Years Before to Two Years After Intervention (Extended Time Frame)	—	—
SECONDARY Medical Cost in US Dollars From Five Years Before to Two Years After Intervention (Extended Time Frame)	—	—
SECONDARY Values From One Year Before to One Year After Intervention of Depressed Mood and Anhedonia as Assessed by the Patient Health Questionnaire-2 (PHQ-2)	—	—
SECONDARY Hemoglobin A1c (hbA1c) From One Year Before to One Year After Intervention	—	—
SECONDARY Low-density Lipoprotein/High-density Lipoprotein (LDL/HDL) Ratios From One Year Before to One Year After Intervention	—	—
SECONDARY High-density Lipoprotein (HDL) Levels From One Year Before to One Year After Intervention	—	—

Summary

The researchers' mission is to promote healthier eating behavior and to reduce costs associated with healthcare. The purpose of this study is to evaluate the effects of mailing randomly selected participants a letter promoting a plant-based diet. Depending on the experimental condition, participants may additionally receive a free documentary, Forks Over Knives, and they may also get letters which use commitment- or prevention-focused messages to encourage watching the documentary and changing their eating behavior. The researchers hypothesize that receiving the documentary will be associated with lower insurance claims and improved health outcomes one and two years later. The researchers also hypothesize that using either commitment- or prevention-focused messages will also contribute to lower insurance claims and improved health outcomes compared to experimental conditions where materials did not include these messages. This study will help the researchers design evidence-supported programs that can improve people's health.

Eligibility Criteria

Inclusion Criteria

Has two out of the three following conditions:
Body mass index over 30
Diagnosis of type 2 diabetes (specifically with at least one medication)
Diagnosis of cardiovascular disease
Has health insurance through Geisinger Health Plan (is an active member with a full 12-month enrollment in the previous year) under one of the following categories:
Medicare with required primary care provider
Medicaid
Individual policy under the Affordable Care Act
Has visited their primary care provider in the past 12 months

Exclusion Criteria

Is institutionalized
Has active cancer, cirrhosis, renal failure, dementia, or active psychosis
Is in the same household as another selected participant

View full record on ClinicalTrials.gov →

Data sourced from ClinicalTrials.gov (NCT03880838). Outcome figures and adverse-event rates are extracted automatically from the registry's posted results and are provided for clinician reference, not as a substitute for the primary publication.