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Trial registered on ANZCTR


Registration number
ACTRN12616001216404
Ethics application status
Approved
Date submitted
18/08/2016
Date registered
2/09/2016
Date last updated
8/08/2017
Type of registration
Retrospectively registered

Titles & IDs
Public title
Effects of whey protein, on energy intake, appetite, antral area, gastric emptying, amino acids, gut hormones and glucose in healthy, undernourished and obese, young and older, individuals
Scientific title
Effects of whey protein, on energy intake, appetite, antral area, gastric emptying, amino acids, gut hormones and glucose in healthy, undernourished and obese, young and older, individuals
Secondary ID [1] 289960 0
Nil known
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Ageing 299947 0
Obesity 299948 0
Undernourishment 299949 0
Condition category
Condition code
Diet and Nutrition 299847 299847 0 0
Obesity
Diet and Nutrition 299848 299848 0 0
Other diet and nutrition disorders
Oral and Gastrointestinal 299849 299849 0 0
Normal oral and gastrointestinal development and function

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
The study will involve healthy, undernourished and obese, younger (18-50 years, n=16 in each group) and older (older than 65 years, n=16 in each group) adults. Healthy subjects will have a BMI of 22-30kg/m2, undernourished of <22 kg/m2 and obese subjects of 30-40kg/m2.

The participant receives a single 450mL preload per study visit in a randomised, crossover fashion of: i) 30 grams Whey Protein Isolate with diet lime cordial flavouring or ii) Water control with diet lime cordial flavouring. All preloads contain 100 microliter of 13C sodium acetate to enable measurement of gastric emptying via 13CO2 in the breath. Gastric emptying rate and intragastric meal distribution will be determined using 3D ultrasound.

Appetite sensation questionnaires in the form of a Visual Analog Scale (VAS) are measured and blood samples are collected for concentrations of gut hormones, amino acids and glucose.

A standard buffet meal is provided at 180 minutes following the preload and the participant has 30 minutes to eat until comfortably full. The buffet meal consists of 300ml orange juice, 600ml water, 375ml iced coffee, 4 slices white bread, 4 slices brown bread, 100g deli leg ham, 100g virginian chicken, 4 slices cheese, 100g tomato, 100g cucumber, 100g lettuce, 2 portions mayonnaise, 2 portions margarine, 1 medium apple, 1 medium banana, 200g chocolate custard, 150g fruit salad, 200g strawberry yoghurt, and a 14g milky way bar. Energy intake from this meal will be quantified.

Each volunteer receives one of each of the 2 treatments on each of the 2 study days. Each study visit is separated by no less than 3 days. Each visit lasts approximately 4 hours.
Intervention code [1] 295647 0
Prevention
Comparator / control treatment
Placebo: a single 450mL water and diet lime cordial preload.
Control group
Placebo

Outcomes
Primary outcome [1] 299326 0
Energy intake at buffet meal
Timepoint [1] 299326 0
Buffet meal is presented at 180 minutes after preload consumption and the subject is allowed to freely consume food until comfortably full for 30 minutes (until t= 210 minutes). The weight of the foods will be recorded before and after it is offered to the subjects and energy intake and macronutrient composition calculated subsequently using commercially available software (Foodworks 3.01, Xyris Software, Highgate Hill, QLD, Australia).
Primary outcome [2] 299327 0
Gastric emptying rate assessed by three-dimensional (3D) ultrasonography
Timepoint [2] 299327 0
3D ultrasound defines the fraction of the meal emptied from the stomach, including 50% emptying time (T1/2), during the study. Ultrasound images will be taken at t= -15, 0, 15, 30, 45, 60, 75, 90, 105, 120, 135, 150, 165 and 180 min, where t=0 is at just after drink consumption.
Primary outcome [3] 299328 0
Gastric emptying rate assessed by 13C sodium acetate breath test.
Timepoint [3] 299328 0
The 13C sodium acetate breath test assesses gastric emptying of the protein drink through measurement of 13CO2 in the breath via mass spectrometry. Half-emptying time and gastric emptying coefficient will also be calculated and compared to those obtained using 3D ultrasonography. Breath samples will be taken at t= -15, 0, 5, 10, 15, 20, 25, 30, 45, 60, 75, 90, 105, 120, 135, 150, 165 and 180 min, where t=0 is at just after drink consumption.
Secondary outcome [1] 326844 0
Blood pressure is determined using an automatic sphygmomanometer.
Timepoint [1] 326844 0
Blood pressure is measured at -15 minutes, 0 minutes (straight after drink consumption) and every three minutes thereafter until 180 minutes. The final measurement is at 210 minutes after the buffet meal has been consumed.
Secondary outcome [2] 326845 0
Heart rate is determined using an automatic sphygmomanometer.
Timepoint [2] 326845 0
Heart rate is measured at -15 minutes, 0 minutes (straight after drink consumption) and every three minutes thereafter until 180 minutes. The final measurement is at 210 minutes after the buffet meal has been consumed.
Secondary outcome [3] 326846 0
Plasma PYY concentrations
Timepoint [3] 326846 0
Blood samples will be taken at t= -15, 0, 15, 30, 45, 60, 90, 120, 150 and 180 min, where t=0 is at just after drink consumption.
Secondary outcome [4] 326847 0
Plasma ghrelin concentrations
Timepoint [4] 326847 0
Blood samples will be taken at t= -15, 0, 15, 30, 45, 60, 90, 120, 150 and 180 min, where t=0 is at just after drink consumption.
Secondary outcome [5] 326848 0
Plasma GLP-1 concentrations
Timepoint [5] 326848 0
Blood samples will be taken at t= -15, 0, 15, 30, 45, 60, 90, 120, 150 and 180 min, where t=0 is at just after drink consumption.
Secondary outcome [6] 326849 0
Plasma GIP concentrations
Timepoint [6] 326849 0
Blood samples will be taken at t= -15, 0, 15, 30, 45, 60, 90, 120, 150 and 180 min, where t=0 is at just after drink consumption.
Secondary outcome [7] 326850 0
Plasma CCK concentrations
Timepoint [7] 326850 0
Blood samples will be taken at t= -15, 0, 15, 30, 45, 60, 90, 120, 150 and 180 min, where t=0 is at just after drink consumption.
Secondary outcome [8] 326851 0
Plasma insulin concentrations
Timepoint [8] 326851 0
Blood samples will be taken at t= -15, 0, 15, 30, 45, 60, 90, 120, 150 and 180 min, where t=0 is at just after drink consumption.
Secondary outcome [9] 326852 0
Plasma glucagon concentrations
Timepoint [9] 326852 0
Blood samples will be taken at t= -15, 0, 15, 30, 45, 60, 90, 120, 150 and 180 min, where t=0 is at just after drink consumption.
Secondary outcome [10] 326853 0
Blood glucose concentrations
Timepoint [10] 326853 0
Blood samples will be taken at t= -15, 0, 15, 30, 45, 60, 90, 120, 150 and 180 min, where t=0 is at just after drink consumption.
Secondary outcome [11] 326854 0
Appetite sensations using a Visual Analog Scale (VAS) ( hunger, fullness, desire to eat, prospective food consumption, thirst).
Timepoint [11] 326854 0
VAS is administered at time points: -15 minutes, 0 minutes (straight after drink consumption) and every fifteen minutes thereafter until 180 minutes. The final VAS is administered at 210 minutes after the buffet meal has been consumed.
Secondary outcome [12] 326855 0
Gastrointestinal symptoms using a Visual Analog Scale (VAS) (bloating, nausea)
Timepoint [12] 326855 0
VAS is administered at time points: -15 minutes, 0 minutes (straight after drink consumption) and every fifteen minutes thereafter until 180 minutes. The final VAS is administered at 210 minutes after the buffet meal has been consumed.
Secondary outcome [13] 326861 0
Amino acid concentrations
Timepoint [13] 326861 0
Blood samples will be taken at t= -15, 0, 15, 30, 45, 60, 90, 120, 150 and 180 min, where t=0 is at just after drink consumption.

Eligibility
Key inclusion criteria
Healthy: BMI 22-30 kg/m2
Undernourished: BMI <22 kg/m2
Obese: BMI >30 kg/m2
Minimum age
18 Years
Maximum age
No limit
Sex
Males
Can healthy volunteers participate?
No
Key exclusion criteria
smokers of cigarettes/cigars/marijuana;

intake of >2 standard drinks on >5 days per week;

intake of >4 cups of caffeinated drinks per day;

intake of any illicit substance;

vegetarians;

lactose intolerance;

Use of prescribed or non-prescribed medications (including vitamins and herbal supplements) which may effect gastrointestinal function or appetite - if subjects are willing, and able, to stop using medications, vitamins and/or supplements which affect gastrointestinal or energy metabolism during the study a washout period of at least 14 days prior to the first test day will apply;

food allergy(s), diabetes mellitus (fasting glucose >6.9 mmol/L), epilepsy, or gallbladder, pancreatic, cardiovascular or respiratory diseases;

significant gastrointestinal symptoms, disease or surgery (apart from uncomplicated appendectomy), as determined by a questionnaire;

impaired cognitive function (score <25 on Mini-Mental State Examination) for older subjects;

depression (a score >11 on the Geriatric Depression Questionnaire) for older subjects;

any other illness deemed significant by the investigator (including chronic illnesses not explicitly listed above);

low ferritin levels (<20ug/l) and plasma Hb levels (<130g/l), or blood donated in the 12 weeks prior to taking part in the study, in line with current Australian Red Cross Guidelines;

individuals who are found to be unable to comprehend the study protocol.

Study design
Purpose of the study
Prevention
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Central randomisation by computer. The study has a within subjects design - all participants receive all interventions in randomised order. The allocation is blinded to the participant and the researcher who performs the screening and who decides whether a subject is eligible to participate. The conditions were coded by a researcher who is not involved in the acquiring the data.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Subjects were randomised by a computer to either receive treatment (A) or placebo (B) on their first visit. The randomisation was designed to create random permutations of treatments for situations where subjects are to receive all of the treatments in random order. The randomisation table was created using http://www.randomization.com/
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?
The people receiving the treatment/s
The people administering the treatment/s
The people assessing the outcomes
The people analysing the results/data
Intervention assignment
Crossover
Other design features
Phase
Not Applicable
Type of endpoint/s
Statistical methods / analysis

Recruitment
Recruitment status
Recruiting
Date of first participant enrolment
Anticipated
Actual
Date of last participant enrolment
Anticipated
Actual
Date of last data collection
Anticipated
Actual
Sample size
Target
Accrual to date
Final
Recruitment in Australia
Recruitment state(s)
SA

Funding & Sponsors
Funding source category [1] 294337 0
Charities/Societies/Foundations
Name [1] 294337 0
Royal Adelaide Hospital Research Foundation - Clinical Project Grant
Country [1] 294337 0
Australia
Primary sponsor type
Individual
Name
Stijn Soenen
Address
Discipline of Medicine, University of Adelaide
Attn.: Stijn Soenen
Level 6 Eleanor Harrald Building,
Frome Road,
Adelaide, SA 5000
Country
Australia
Secondary sponsor category [1] 293175 0
University
Name [1] 293175 0
The University of Adelaide
Address [1] 293175 0
North Terrace
Adelaide, SA, 5000
Country [1] 293175 0
Australia

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 295757 0
Royal Adelaide Hospital Research Ethics Committee
Ethics committee address [1] 295757 0
Level 3, Hanson Institute, North Terrace
Adelaide, South Australia, 5000
Ethics committee country [1] 295757 0
Australia
Date submitted for ethics approval [1] 295757 0
05/08/2016
Approval date [1] 295757 0
08/08/2016
Ethics approval number [1] 295757 0
R20120503

Summary
Brief summary
Ageing is associated with a physiological reduction of appetite and energy intake, which has been called the “anorexia of ageing”. Dietary supplementation with liquid protein preparations is now used frequently to increase energy and protein intake in older adults in both institutionalized and community-dwelling populations. Although the latter would appear a logical approach, evidence for success of increased energy intake in older individuals is limited. Urgent investigation is warranted to determine the optimal load of protein that can be incorporated into their diet to assist in sparing muscle mass without reducing their appetite. Moreover, weight loss protein-rich diets are often recommended for obese older adults in the same manner as for younger adults. In young adults, obese individuals exhibit a less precise compensatory response to ingested energy than lean individuals. Although only a limited number of studies have examined the effects of state of nutrition in elderly on the regulation of appetite, there is persuasive evidence of substantial differences between undernourished and healthy older people, which may potentially represent an outcome of and/or contribute to the undernourished state. A common strategy to increase energy intake and body weight in undernourished elderly is the use of nutritional supplements, and this is now almost standard practice. Usually such supplements are provided as mixed macronutrient high-energy drinks. Because of the increasing awareness of the major muscle loss that preferentially accompanies weight loss in older people, and its particular adverse effects, there has been a recent, marked, increase in the preferential administration of protein in these supplements and the use of protein-enriched supplements in an attempt to preserve, or even increase, muscle mass, in both institutionalized and community-dwelling populations. Such recommendations and use are, however, largely empirical. Our understanding of the feeding responses, and mechanisms underlying them, of undernourished and obese older people to protein is very limited and will be increased greatly by the proposed study.

To aim of the study is to characterise in undernourished and obese, young and older individuals, the effect of different oral protein loads on energy intake, appetite, antral area, gastric emptying, plasma concentrations of amino acids, hormones (i.e. CCK, PYY, ghrelin, GLP-1, GIP, glucagon and insulin) and glucose, and to determine the relationship between the suppression of appetite and energy intake by protein with ‘intragastric’ and ‘small intestinal’ mechanisms.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 68350 0
Dr Stijn Soenen
Address 68350 0
Discipline of Medicine, University of Adelaide Attn.: Stijn Soenen Level 6 Eleanor Harrald Building, Frome Road, Adelaide, SA 5000
Country 68350 0
Australia
Phone 68350 0
+61 8 8313 3638
Fax 68350 0
Email 68350 0
Contact person for public queries
Name 68351 0
Dr Stijn Soenen
Address 68351 0
Discipline of Medicine, University of Adelaide Attn.: Stijn Soenen Level 6 Eleanor Harrald Building, Frome Road, Adelaide, SA 5000
Country 68351 0
Australia
Phone 68351 0
+61 8 8313 3638
Fax 68351 0
Email 68351 0
Contact person for scientific queries
Name 68352 0
Dr Stijn Soenen
Address 68352 0
Discipline of Medicine, University of Adelaide Attn.: Stijn Soenen Level 6 Eleanor Harrald Building, Frome Road, Adelaide, SA 5000
Country 68352 0
Australia
Phone 68352 0
+61 8 8313 3638
Fax 68352 0
Email 68352 0

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No Supporting Document Provided



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