Clinical trial NCT05994313: STARchy Staples: a Randomised Controlled Trial on Cardiometabolic Health
Official title: STARchy Staples: a Randomised Controlled Trial on Cardiometabolic Health
Study type: INTERVENTIONAL
Overall status: RECRUITING
Phase: NA
Conditions: Cardiometabolic Health
Keywords: Sleep efficiency
Glycemic control
Flow mediated dilation
Lead sponsor: King's College London
Sponsor class: OTHER
Collaborators: name: Alliance for Potato Research and Education
name: Maastricht University
First posted: 2023-08-16
Enrollment: 80
Sex: ALL
Minimum age (years): 40
Maximum age (years): 80
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: PARALLEL
Intervention model description: 12-week Randomised controlled trial
Primary purpose: BASIC_SCIENCE

Brief summary: An investigation into habitual potato consumption (mashed, boiled, baked) on sleep quality and chronic glycaemic control, established risk factors for cardiometabolic diseases, versus habitual consumptions of non-nutrient-dense starchy staples (white rice, pasta, and couscous).

Detailed description: In the last few years, researchers have undergone efforts to conduct well-controlled trials to investigate the cardiometabolic health effect of consuming potatoes as part of a healthy diet. None to our knowledge, however, have investigated the harmful dyad of poor sleep and adverse glycaemic control, 2 interrelated factors which can exacerbate cardiometabolic (CM) health outcomes. The nutrient density of potatoes, namely being the single richest source of potassium per serving, provides a plausible mechanism in which the potatoes may act to improve health markers.

The primary objective of this study is to investigate whether consuming a portion of nutrient-dense potatoes in the evening meal, in place of other refined carbohydrates, can improve sleep quality, and improve nocturnal, and 24-hour, glycaemic control, both risk factors for CM diseases. Secondly, this study aims to investigate the effects of potato consumption on endothelium-dependent vasodilation, which can further interrelate to this web of interactions, and other measures of CM health.

Study design: A randomised, two-parallel arm, in-clinic and remote, 12-week dietary intervention study.

Study population: Healthy male and female 40-80-year-olds, who consume ≤4 fruits and vegetables per day and have sub-optimal sleep quality.

The study aims to recruit a total of 80 participants, allowing for an estimated 15% dropout rate, to reach 80% power at a significance level of 0.025 (based on two outcomes). The allocation ratio is 1:1 intervention to control.

Locations:

Metabolic Research Unit, 4th floor, Franklin Wilkins Building, Waterloo campus, Kings College London, SE1 9NH.

Screening assessment: Participants will be initially assessed for suitability against the inclusion-exclusion criteria via an online questionnaire. The outputs of the questionnaire will be assessed by the study team. Some exclusion criteria will be assessed at the baseline clinic visit before any baseline measures are provided.

Study duration: There will be a 2-week run-in period, followed by a 12-week dietary intervention.

Dietary intervention: The intervention (potato group) will consume at least 220 g of white potatoes (25% of energy intake from carbohydrates, or 12.5% of total energy intake, including fresh and frozen baked, boiled, and mashed potato products) in their evening meal, providing \~800 mg potassium, enough to increase national median intakes up to recommended intakes. The control group will consume isoenergetic amounts of non-nutrient-dense starchy staples (white pasta, white rice, or couscous).

Although participants cannot be blinded to what they're consuming, they will be blinded to whether they are in the control or the intervention group, to reduce the risk of bias.

Participants will be required to source the potatoes and make these meals themselves, however, they will be provided with rotating 4-weekly recipe cards, with instructions on how to prepare meals.

Participants will be required to attend several virtual one-to-ones with the study team, including an introductory call, a virtual run-in induction where they will be run through the study equipment, and 2 in-person clinic visits. Participants will be responsible for applying some study equipment from home, to reduce clinic visits and improve study retention.

Compliance: Compliance will be monitored via several methods. Firstly, 24 h urinary potassium excretion, which is shown to recover 75% of potassium intake, secondly self-reported compliance will be measured through evening meal checklists. We also plan to use dietary recalls at weeks 2, 4, and 8 to reinforce dietary advice, and to make adaptations to rotating menus based on individual needs, if participants are struggling with adherence. Detailed dietary intake will be assessed through 4-day food diaries at weeks 0, 6, and 12- this data will be used for analysis.

Flow-mediated dilation: A Doppler ultrasound will be utilised to capture continuous ultrasound videos to measure flow-mediated dilation. These will be analysed with automated software provided by Maastricht University.

Anthropometry: Weight, height, waist and hip circumference, blood pressure, and body fat will be taken using standard procedures, in duplicates by a trained researcher at baseline and endline clinic visits.

Blood samples: Fasting blood samples will be collected from a superficial antecubital vein via venepuncture before and after the dietary intervention, by a trained researcher.

Participants will be asked to record and monitor the following information:

Self-reported compliance with dietary intervention, weekly weight (data diaries), and habitual dietary intake (4-day diet diaries).

Eligibility criteria: Inclusion Criteria:

* Self-reported healthy adults
* Aged 40-80 years old
* Intake of ≤4 portions of fruits and vegetables (excluding potatoes) per day
* Low sleep quality index of \>5 (Pittsburgh sleep quality index).

Exclusion Criteria:

* Shift workers and those with multiple jobs or carers who are required to wake through the night
* Unwilling to refrain from dietary supplements
* Unwilling to follow protocol and/or give informed consent
* Diagnosed with Cardiovascular Disease (CVD), Type 2 Diabetes, Celiac disease, Insomnia, Sleep apnoea
* Presence of gastrointestinal disorder
* Users of drugs that are likely to alter gastrointestinal motility or nutrient absorption
* History of substance abuse or alcoholism
* Currently pregnant, planning pregnancy, breastfeeding, or having had a baby 12 months prior
* Weight change of \>3kg in the preceding 2 months
* BMI \<18.5kg/m2 or \> 35kg/m2,
* Current smokers, or individuals who quit smoking in the last 6-months
* Frequently consume wholemeal products (1-2 times per day, in the short screening FFQ)
* Never consumed refined starchy staples, such as white pasta or rice (rarely or never, in the short screening FFQ)
* High potato consumption (4-6 times per week, in the short screening FFQ)
* High risk of obstructive sleep apnoea (answer yes to \>3 questions, in STOP-Bang questionnaire)
* Vegetarian, Vegan, or pescatarian dietary preferences.
* Diagnosed with mental health disorders, and/or on medicine for their mental health (antipsychotics, antidepressants, beta-blockers)
* Chronic user of antihistamines
* Fasting glucose \>7mmol/l (finger prick test at baseline clinic)
* Is taking weight loss, or glucose regulating medications.
* Has been unstable on blood pressure lowering medications for at least 3-months prior to enrollment.

Primary outcomes:
measure: Change in 7-day sleep efficiency
timeFrame: 12 weeks
measure: Change in 12-day nocturnal glycaemic control
timeFrame: Pre- and post-intervention: 12 weeks
Secondary outcomes:
measure: Change in 12-day daytime glycaemic control
timeFrame: Pre- and post-intervention: 12 weeks
measure: Change in 24-hour nocturnal glycaemic control
timeFrame: Pre- and post-intervention: 12 weeks
measure: Change in heart rate variability during mental stress
timeFrame: Pre- and post-intervention: 12 weeks
measure: Change in 24-hour heart rate variability
timeFrame: Pre- and post-intervention: 12 weeks
measure: Change in Endothelial function
timeFrame: Pre- and post-intervention: 12 weeks
measure: 12-week nighttime continuous blood pressure
timeFrame: Whole 12 week period.
measure: 12-week daytime continuous blood pressure
timeFrame: Whole 12 week period.
measure: Change in blood pressure
timeFrame: Pre- and post-intervention: 12 weeks
measure: Change in plasma lipids
timeFrame: Pre- and post-intervention: 12 weeks
measure: Change in fasting plasma glucose
timeFrame: Pre- and post-intervention: 12 weeks
measure: Change in fasting insulin
timeFrame: Pre- and post-intervention: 12 weeks
measure: Change in fasting HbA1C
timeFrame: Pre- and post-intervention: 12 weeks
measure: Change in sleep duration, in minutes
timeFrame: Pre- and post-intervention: 12 weeks
measure: Change in sleep duration, in %
timeFrame: Pre- and post-intervention: 12 weeks
measure: Change in sleep latency
timeFrame: Pre- and post-intervention: 12 weeks
measure: Change in body fat %
timeFrame: Pre- and post-intervention: 12 weeks
measure: Change in waist circumference (cm)
timeFrame: Pre- and post-intervention: 12 weeks
measure: Change in BMI kg/m2
timeFrame: Pre- and post-intervention: 12 weeks
measure: Change in diet quality
timeFrame: Pre- and post-intervention: 12 weeks
Other outcomes:
measure: Change in meal satiety
timeFrame: Total of 15 satiety scales: 1 pre- and 4 postprandial scales (-1, 1, 2, 3 hours after), in 3 in food diaries (week 0, week 6 and week 12).
Locations:
city: Lambeth
country: United Kingdom
facility: Department of Nutritional Sciences, Franklin Wilkins Building, Waterloo campus.
state: London
Study officials:
affiliation: King's College London
name: Wendy Hall, PhD
role: PRINCIPAL_INVESTIGATOR
References:
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citation: Stone MS, Martin BR, Weaver CM. Short-Term RCT of Increased Dietary Potassium from Potato or Potassium Gluconate: Effect on Blood Pressure, Microcirculation, and Potassium and Sodium Retention in Pre-Hypertensive-to-Hypertensive Adults. Nutrients. 2021 May 11;13(5):1610. doi: 10.3390/nu13051610.
citation: Johnston EA, Petersen KS, Kris-Etherton PM. Daily intake of non-fried potato does not affect markers of glycaemia and is associated with better diet quality compared with refined grains: a randomised, crossover study in healthy adults. Br J Nutr. 2020 May 14;123(9):1032-1042. doi: 10.1017/S0007114520000252. Epub 2020 Jan 22.
citation: Macdonald-Clarke CJ, Martin BR, McCabe LD, McCabe GP, Lachcik PJ, Wastney M, Weaver CM. Bioavailability of potassium from potatoes and potassium gluconate: a randomized dose response trial. Am J Clin Nutr. 2016 Aug;104(2):346-53. doi: 10.3945/ajcn.115.127225. Epub 2016 Jul 13.
citation: D'Elia L, Masulli M, Cappuccio FP, Zarrella AF, Strazzullo P, Galletti F. Dietary Potassium Intake and Risk of Diabetes: A Systematic Review and Meta-Analysis of Prospective Studies. Nutrients. 2022 Nov 12;14(22):4785. doi: 10.3390/nu14224785.