Cardiometabolic Effects of Pecans as a Snack

Phase 2

Completed

Conditions: Cardiovascular Diseases

Interventions: Other: Usual Care
Drug: Pecans

Registration Number: NCT05071807

Lead Sponsor: Penn State University

Brief Summary: A randomized, 2-arm, parallel trial will be conducted to examine the effect of pecans on markers of peripheral vascular health, lipids and lipoproteins, blood pressure, and glycemic control.

Detailed Description: A randomized, 2-arm, parallel trial will be conducted to examine the effect of including 2 oz./day of pecans, as a snack, compared to a diet typically consumed by participants intake (devoid of nuts) on markers of peripheral vascular health, lipids and lipoproteins, blood pressure, and glycemic control. Participants will be randomized to pecans or control for 12-weeks. Outcome assessments will be measured at baseline and 12-weeks.

Recruitment & Eligibility

Status: COMPLETED

Sex: All

Target Recruitment: 138

Inclusion Criteria

BMI 25-40 kg/m2
≥ 1 criterion for metabolic syndrome (i.e., waist circumference ≥ 94 cm men or ≥ 80 cm women; triglycerides ≥150 mg/dL; HDL-cholesterol ≤ 40 mg/dL men or ≤ 50 mg/dL women; systolic blood pressure ≥130 mmHg or diastolic blood pressure ≥85 mmHg; fasting plasma glucose ≥100 mg/dL) at screening

Exclusion Criteria

Current use of tobacco-containing products or (≤6 months) cessation
Allergy/sensitivity/intolerance/dislike of study foods
Women who are pregnant, lactating, planning to become pregnant or have given birth in the past year
Individuals who have had a cardiovascular event (heart attack, revascularization, stroke), or have a history of heart failure, liver, kidney, autoimmune diseases or inflammatory conditions such as gastrointestinal disorders or rheumatoid arthritis.
Type 1 or type 2 diabetes
Unstable weight ≥10% body weight for 6 months prior to enrollment
Systolic Blood pressure >160 mmHg for systolic pressure and/or diastolic blood pressure >/100 mmHg for diastolic pressure at screening
Fasting blood glucose ≥126 mg/dL at screening
Triglycerides ≥350 mg/dL at screening
Taking any medications known to affect lipids, blood pressure, or blood glucose levels
Diagnosed inflammatory conditions or taking prescribed , taking any chronic anti-inflammatory medications (>1 time per week over the past 3 months)
Use of antibiotics within the prior 8 weeks
Taking supplements (e.g., psyllium, fish oil, soy lecithin, and phytoestrogens) and botanicals known to affect study outcomes and not willing to cease for the duration of the study
Individuals consuming >14 alcoholic drinks/week, and not willing to avoid alcohol consumption for 48 hours prior to test visit
Pre-menopausal women who do not have a regular menstrual cycle of 25-35 days
PI discretion

Study & Design

Study Type: INTERVENTIONAL

Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Usual Care Group	Usual Care	Participants will consume their usual diet devoid of nuts
Pecan Group	Pecans	Participants will consume their usual diet, but replace one snack with unsalted raw pecans incorporated as a snack

Primary Outcome Measures

Name	Time	Method
Flow Mediated Dilation	12 weeks	Measured by brachial ultrasound and expressed as percentage points of change in arterial diameter

Secondary Outcome Measures

Name	Time	Method
Triglycerides	12 weeks	Assessed from fasting blood draw expressed in mg/dL
Brachial Systolic and Diastolic Blood Pressure	12 weeks	Blood pressure measured assessed using a SphygmoCor Xcel (Atcor Medical)
LDL-cholesterol Concentration	12 weeks	Assessed from fasting blood draw expressed in mg/dL
HDL-cholesterol Concentration	12 weeks	Assessed from fasting blood draw expressed in mg/dL
HDL Lipoprotein Subclasses	12 weeks	Assessed from fasting blood draw expressed in µmol/L; Measure Description: Size classifications of HDL subclasses are as follows: large (size 9.4-14.0 nm), medium (8.3-9.3 nm), and small (7.3-8.2 nm). Higher levels of large HDL may be inversely related to cardiovascular risk.
LDL Lipoprotein Subclasses	12 weeks	Assessed from fasting blood draw expressed in nmol/L. Data were log transformed and back transformed to improve residual distribution; Measure Description: LDL particle size classifications are as follows: 22-25.5 nm is small, 25.6-26.5 nm medium, and 26.6-28.5 nm large. Typically, smaller LDL is associated with increased cardiovascular risk compared to larger.
HbA1c	12-weeks	HbA1c assessed in whole blood collected during fasting
Total Cholesterol Concentration	12-weeks	Assessed from fasting blood draw expressed in mg/dL
LDL Subclasses	12 weeks	LDL subclasses with normal distribution; Measure Description: LDL particle size classifications are as follows: 22-25.5 nm is small, 25.6-26.5 nm medium, and 26.6-28.5 nm large. Typically, smaller LDL is associated with increased cardiovascular risk compared to larger.
HDL Subclass-Large	12 weeks	Measure was log transformed and back transformed to improve distribution; results for large HDL subclass are presented; Measure Description: Size classifications of HDL subclasses are as follows: large (size 9.4-14.0 nm), medium (8.3-9.3 nm), and small (7.3-8.2 nm). Higher levels of large HDL may be inversely related to cardiovascular risk.
Central Systolic and Diastolic Blood Pressure	12 weeks	Blood pressure measured assessed using a SphygmoCor Xcel (Atcor Medical)
Carotid-femoral Pulse Wave Velocity	12 weeks	A measure of arterial stiffness assessed using a SphygmoCor Xcel (Atcor Medical). Expressed in meters/second. Higher values indicate greater arterial stiffness
Augmentation Index@75bpm	12 weeks	A measure of arterial stiffness assessed using a SphygmoCor Xcel (Atcor Medical). Expressed as a percentage. A higher percentage value is indicative of greater arterial stiffness. Measure Description: Augmentation index is a measure of arterial stiffening that correlates with CVD risk. Higher augmentation index, used as a surrogate for wave reflection, is indicative of additional load on the left ventricle. Augmentation index is calculated as augmentation pressure/pulse pressure\*100 to provide a percent. We utilized the Sphymocor Xcel for this measure. We used standardized augmentation index at 75 bpm for heart rate.
Fasting Plasma Glucose Concentration	12 weeks	Fasting blood glucose assessed by blood draw and expressed in mg/dL
Serum Insulin Concentration	12 weeks	Fasting serum insulin levels assessed by blood draw and expressed in micro IU/m
Diet Quality: Healthy Eating Index 2020	12-weeks	Diet quality measured by 24-hour recalls will be assessed using Health Eating Index 2020 (HEI-2020) scores range from 0-100 with 100 indicating perfect adherence to dietary guidelines and 0 indicating no adherence. The HEI-2020 includes 13 components; 9 components are adequacy (i.e., consuming more results in a higher score), and 4 are moderation (i.e., consuming less results in a higher score). The HEI-2020 was calculated with the Statistical Analysis System (SAS) code from the National Cancer Institute.