ANZCTR - Registration

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Trial registered on ANZCTR

Registration number

ACTRN12615000070538

Ethics application status

Approved

Date submitted

9/01/2015

Date registered

27/01/2015

Date last updated

8/08/2017

Type of registration

Prospectively registered

Titles & IDs

Public title

Effects of timing of protein ‘preloads’ on appetite and energy intake in healthy older individuals

Scientific title

Effects of timing of oral protein 'preloads', on energy intake, appetite, hormones, glucose and blood pressure in healthy older individuals

Secondary ID [1]

Nil

Universal Trial Number (UTN)

Nil

Trial acronym

Nil

Linked study record

Health condition

Health condition(s) or problem(s) studied:

Anorexia of ageing

Condition category

Condition code

Diet and Nutrition

Other diet and nutrition disorders

Oral and Gastrointestinal

Normal oral and gastrointestinal development and function

Intervention/exposure

Study type

Interventional

Description of intervention(s) / exposure

16 healthy older subjects (65+ years) will be included in the study. In a randomised intervention order, the subjects will be studied on 5 occasions after an overnight fast. The study visits will be seperated by at least 3 days. Drink ingestion at 0, 60, 120 and 180 min of either whey protein isolate drink P or iso-palatable control drink C (~0kcal): i) P/C/C/C, ii) C/P/C/C, iii) C/C/P/C, iv) C/C/C/P and v) C/C/C/C (control study day). The protein drink will contain 30 g food-grade whey protein isolate powder dissolved in 70 mL distilled water and 50 mL low-calorie lime cordial (Bickfords diet lime cordial). The control drink will contain 90 mL distilled water and 40 mL low calorie lime cordial. The drinks will be equivolaemic (130 mL), and matched for taste. A baseline venous blood sample will be taken and the subject will complete a visual analogue scale (VAS) to assess appetite-related sensations. VAS questionnaires will be collected at t=-2 min (baseline) and t= 2, 27, 57, 62, 87, 117, 122, 147, 177, 182 and 212 min. Blood samples (11.4 mL each) will be collected at 7 time points t = -5 min (baseline) and t = 25, 55, 85, 115, 145, and 175 min). Blood pressure and heart rate will be measured prior to the drink (baseline) and at 3 minute intervals from t = 0 - 180 minutes and after the buffet meal t = 210 min. At t = 180 min, the intravenous cannula will be removed and subjects will be presented with a cold, buffet-style meal. Subjects will be allowed 30 min to freely consume food until they feel comfortably full. 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.

Intervention code [1]

Prevention

Comparator / control treatment

Placebo: a single 130mL water and diet lime cordial preload.

Control group

Placebo

Outcomes

Primary outcome [1]

Total energy intake of a standard buffet meal (quantified using Foodworks software).

Timepoint [1]

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).

Primary outcome [2]

Appetite sensations using a Visual Analogue Scale (VAS) (nausea, hunger, fullness, desire to eat, thirst).

Timepoint [2]

VAS is administered at baseline (t=-2) and at time points 2, 27, 57, 62, 87, 117, 122, 147, 177, 182 and 212 min after preload consumption

Secondary outcome [1]

Macronutrient intake of a standard buffet meal (quantified using Foodworks software).

Timepoint [1]

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).

Secondary outcome [2]

Systolic blood pressure is determined using an automatic sphygmomanometer.

Timepoint [2]

Systolic blood pressure is measured prior to the drink (i.e. baseline mean of three samples, t = -9, -6, -3) and at 3 minute intervals from t = 0 – 180 minutes and after the buffet meal t = 210 min.

Secondary outcome [3]

Diastolic blood pressure is determined using an automatic sphygmomanometer.

Timepoint [3]

Diastolic blood pressure is measured prior to the drink (i.e. baseline mean of three samples, t = -9, -6, -3) and at 3 minute intervals from t = 0 – 180 minutes and after the buffet meal t = 210 min.

Secondary outcome [4]

Heart rate is determined using an automatic sphygmomanometer.

Timepoint [4]

Heart rate is measured prior to the drink (i.e. baseline mean of three samples, t = -9, -6, -3) and at 3 minute intervals from t = 0 – 180 minutes and after the buffet meal t = 210 min.

Secondary outcome [5]

Cholecystokinin concentrations (CCK)

Timepoint [5]