The Heart Institute of Spokane Diet Study

The Heart Institute of Spokane Diet Intervention and Evaluation Trial (THIS DIET)

The purpose of this study is to determine whether a Mediterranean style diet, enriched in monounsaturated and omega-3 fats, is superior to the American Heart Association Step 2 diet, a traditional low fat diet, for improving rates of survival and cardiovascular complications in persons who have had a first myocardial infarction (heart attack).

Study Overview

• Status: Completed
• Conditions: Myocardial Infarction
• Intervention / Treatment: Behavioral: Mediterranean diet; Behavioral: American Heart Association Step 2 diet

Detailed Description

Cardiovascular diseases (heart attack, stroke, and other vascular diseases) are major causes of mortality in developed countries. Although medicines and revascularization procedures prolong lives, rates of death and disability remain high. Lifestyle factors greatly contribute to risk. Yet, scientific data regarding the role of lifestyle change in prevention and treatment are limited. In the nutrition area, limitations include observational or uncontrolled study design, and focus on surrogate markers rather than on clinical outcomes.

Excess dietary fat has long been associated with cardiovascular diseases. Increased risk is related both to types of fat and calories from fat. Saturated fat, cholesterol, and trans-fatty acids have all been associated with adverse outcomes. Because fat is calorie-laden, high fat diets are commonly associated with weight gain and obesity. Low-fat diets have traditionally been recommended to control lipids and weight. However, these diets are high in carbohydrate and may actually be associated with weight gain if calories are not limited. Such diets have also been associated with worsening of hyperinsulinemia and insulin resistance and an adverse lipid pattern (low HDL cholesterol and high triglyceride levels). In contrast, increased intake of monounsaturated and omega-3 fats is associated with favorable effects on cardiovascular risk factors and markers including: endothelial function, lipids, and levels of insulin and glucose. Results have been consistent across various groups of high-risk patients, including those with hypercholesterolemia, diabetes, and hypertension. Most importantly, a Mediterranean style diet enriched in monounsaturated and omega-3 fats reduced death and cardiovascular complications after myocardial infarction (MI) in the Lyon Heart study.

The American Heart Association (AHA) Step 2 is a low-fat diet traditionally recommended for people with cardiovascular disease. The Mediterranean and AHA Step 2 diets differ primarily in the amount of monounsaturated and omega-3 fats, both of which are higher in the Mediterranean diet. Both diets are low in saturated fat (less than 7%) and cholesterol (less than 200 mg/d). Although the Lyon Heart Study compared a Mediterranean diet to a "prudent Western diet," a low fat diet similar to the AHA diet, the latter group did not achieve recommended intake levels of saturated fat or cholesterol. Furthermore, there was no longitudinal nutritional intervention in the low fat diet group. Therefore, the effect of nutritional intervention per se was not addressed.

Comparison(s): In survivors of a first MI, two longitudinal nutritional interventions, a Mediterranean style diet and an AHA Step 2 diet, will be compared. Both intervention groups will be compared to an untreated control group from our clinical database.

• Study Type: Interventional
• Enrollment (Actual): 202
• Phase: Phase 3

Contacts and Locations

Study Locations

• United States
  • Washington
    • Spokane, Washington, United States, 99204
      • Providence Medical Research Center

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 16 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• First myocardial infarction

Exclusion Criteria:

• Prior myocardial infarction
• Uncontrolled or secondary hypertension
• New York Heart Association heart failure stage III or IV
• Ventricular arrythmias requiring medical or defibrillatory intervention
• Other diseases that may make study completion difficult or unlikely

Study Plan

How is the study designed?

Design Details

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

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Mediterranean diet,	Behavioral: Mediterranean diet; Mediterranean style diet with patient education and diet analysis
Experimental: American Heart Association Step 2 diet	Behavioral: American Heart Association Step 2 diet; Low fat diet with patient education and diet analysis; Other Names: Low fat diet
No Intervention: Case controlled

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Fatal/non-fatal myocardial infarction	The primary outcome was a composite of end points including all-cause and cardiac deaths, MI, hospital admissions for heart failure, unstable angina, or stroke.	3,6,12,18,24,36,48,60,72 months
Cardiovascular death		3,6,12,18,24,36,48,60,72 months
Non-cardiovascular death		3,6,12,18,24,36,48,60,72 months
Stroke/TIA		3,6,12,18,24,36,48,60,72 months
Admission for congestive heart failure or unstable angina		3,6,12,18,24,36,48,60,72 months

Secondary Outcome Measures

Outcome Measure	Time Frame
Cardiovascular revascularization	3,6,12,18,24,36,48,60,72 months
Peripheral revascularization or amputation	3,6,12,18,24,36,48,60,72 months
Doubling of serum creatinine,dialysis,or kidney transplant	3,6,12,18,24,36,48,60,72 months
New hypertension	3,6,12,18,24,36,48,60,72 months
New diabetes	3,6,12,18,24,36,48,60,72 months
Risk factors (traditional and novel)	3,6,12,18,24,36,48,60,72 months

Collaborators and Investigators

• Sponsor: Providence Health & Services
• Collaborators: The Heart Institute of Spokane; Providence Medical Research Center; Washington State Attorney General's Office; Deaconess Medical Center, Spokane, Washington
• Investigators: Principal Investigator: Katherine R. Tuttle, MD,FASN,FACP, Providence Medical Research Center

Study record dates

Study Major Dates

• Study Start: October 1, 2000
• Primary Completion (Actual): January 1, 2008
• Study Completion (Actual): January 1, 2008

Study Registration Dates

• First Submitted: December 22, 2005
• First Submitted That Met QC Criteria: December 22, 2005
• First Posted (Estimate): December 23, 2005

Study Record Updates

• Last Update Posted (Estimate): August 24, 2010
• Last Update Submitted That Met QC Criteria: August 23, 2010
• Last Verified: December 1, 2005

More Information

Terms related to this study

• Keywords: Cardiovascular disease; Nutrition; Outcomes; Mediterranean diet; Low fat diet; American Heart Association diet; Monounsaturated fats; Omega-3 fats
• Additional Relevant MeSH Terms: Ischemia; Pathologic Processes; Necrosis; Myocardial Ischemia; Heart Diseases; Cardiovascular Diseases; Vascular Diseases; Myocardial Infarction; Infarction
• Other Study ID Numbers: THIS-A20010724157261