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Trial details imported from ClinicalTrials.gov

For full trial details, please see the original record at https://clinicaltrials.gov/show/NCT01771042




Registration number
NCT01771042
Ethics application status
Date submitted
15/01/2013
Date registered
18/01/2013
Date last updated
18/01/2013

Titles & IDs
Public title
The Effects of Weight Loss on Neuroadrenergic Function
Scientific title
Neuroadrenergic Dysfunction Along the Diabetes Continuum: Benefits of Weight Loss Within Different Strata of Metabolic Risk
Secondary ID [1] 0 0
1/13
Secondary ID [2] 0 0
1/13
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Obesity 0 0
Type 2 Diabetes 0 0
Metabolic Syndrome 0 0
Condition category
Condition code
Metabolic and Endocrine 0 0 0 0
Metabolic disorders

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Other interventions - Dietary weight loss at 25% energy deficit

Experimental: Normal glucose tolerant - Weight loss attained by 25% caloric restriction.
This arm will be both a glycemic and time control. Initially they will undergo a 4-month weight maintenance phase (acting as time control), followed by 4 month weight loss.

Experimental: Impaired glucose tolerant - Weight loss using 25% caloric restriction.
Impaired glucose tolerant subjects will undergo 4 months weight loss (25% caloric deficit) followed by 3 months weight loss maintenance

Experimental: Type 2 diabetic hyperinsulinemic - Weight loss using 25% caloric restriction.
This group will undergo 4 months weight loss (25% caloric deficit) followed by 3 months weight loss maintenance

Experimental: Type 2 diabetic hypoinsulinemic - Weight loss via 25% caloric restriction.
This group will undergo 4 months weight loss (25% caloric deficit) followed by 3 months weight loss maintenance


Other interventions: Dietary weight loss at 25% energy deficit
Dietary weight loss at 25% energy deficit. Dietary macronutrient content will comprise 25% protein, 30% fat and 45% carbohydrate.

Intervention code [1] 0 0
Other interventions
Comparator / control treatment
Control group

Outcomes
Primary outcome [1] 0 0
Change in whole-body norepinephrine kinetics - The study will examine the dynamic processes of norepinephrine spillover into and removal from the central plasma compartment using the isotope dilution technique.Measurements will be made at baseline, after 4 months active weight loss, and again after 3 months weight loss maintenance. The weight loss maintenance phase will permit differentiation of the effects of active weight loss (incorporating both negative energy balance and weight loss per se) and stable lower body weight on sympathetic neural parameters.
Timepoint [1] 0 0
4 months and 7 months
Secondary outcome [1] 0 0
Change in muscle sympathetic nerve activity - Muscle sympathetic nerve firing will be quantified by the technique of mirconeurography at baseline and after 4 months active weight loss and 3 months weight loss maintenance. The weight loss maintenance phase will permit differentiation of the effects of active weight loss (incorporating both negative energy balance and weight loss per se) and stable lower body weight on sympathetic nerve firing and pattern.
Timepoint [1] 0 0
4 months and 7 months

Eligibility
Key inclusion criteria
Men and postmenopausal women (n=120), untreated, weight-stable, non-smoking, aged 45-65
years, BMI 27-45 kg/m2, will be recruited. Glucose tolerance status will be determined by a
75-g oral glucose tolerance test (OGTT), using WHO criteria (53): normal glucose tolerance,
fasting plasma glucose < 7.0 mmol/L and 2-h plasma glucose < 7.8 mmol/L; IGT, fasting
plasma glucose < 7.0 mmol/L and 2-h plasma glucose > 7.8 and < 11.1 mmol/L; T2D, fasting
plasma glucose > 7.0 mmol/L or 2-h plasma glucose > 11.1 mmol/L. Hyper-insulinemia will be
defined as an insulin area under the curve during OGTT > 8000 mU/L · min-1 and
hypo-insulinemia as < 8000 mU/L · min-1.
Minimum age
45 Years
Maximum age
65 Years
Gender
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
Prior history of cardiovascular disease (previous myocardial infarction, angina, stroke,
heart failure, secondary hypertension), renal (serum creatinine >0.12 mmol/L or estimated
GFR <60 ml/min/1.73 m2) or hepatic disease or diseases which may affect measured parameters
(e.g. thyroid disease); severe hypertension; a history of surgical weight loss; CPAP
therapy; and >4 alcoholic drinks/day. T2D individuals with moderate hyperglycemia (HbA1c
>9%) will be excluded so that hypoglycaemic pharmacotherapy may be instituted (54).
Participants will be sought through newspaper advertising and poster displays in primary
health care centres (General Practices). Newly diagnosed T2D subjects

Study design
Purpose of the study
Treatment
Allocation to intervention
Non-randomised trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Masking / blinding
Open (masking not used)
Who is / are masked / blinded?



Intervention assignment
Parallel
Other design features
Phase
Not Applicable
Type of endpoint(s)
Statistical methods / analysis

Recruitment
Recruitment status
Unknown status
Data analysis
Reason for early stopping/withdrawal
Other reasons
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)
VIC
Recruitment hospital [1] 0 0
Baker IDI Heart & Diabetes Institute - Melbourne
Recruitment postcode(s) [1] 0 0
8008 - Melbourne

Funding & Sponsors
Primary sponsor type
Other
Name
Baker Heart Research Institute
Address
Country

Ethics approval
Ethics application status

Summary
Brief summary
Elevated subconscious nervous system activity is a characteristic of the obese state and
contributes importantly to the risk of heart disease and diabetes. This project will compare
sympathetic nervous system activity and function in a group of obese persons with differing
levels of sugar tolerance (normal, impaired and type 2 diabetic). Inter-relationships with
insulin action, blood pressure, heart and kidney function will be determined before and after
a 4-month weight loss and 3-month weight loss maintenance program.

It is hypothesized that the transition from normal sugar tolerance to impaired sugar
tolerance to type 2 diabetes will be accompanied by escalating sympathetic nervous system
dysfunction. Furthermore, that weight loss will favorably improve sympathetic function, with
greatest benefits occurring in those subjects who are insulin resistant with high blood
insulin concentration.
Trial website
https://clinicaltrials.gov/show/NCT01771042
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 0 0
Dr Nora E Straznicky, PhD MPH
Address 0 0
Baker IDI Heart & Diabetes Institute
Country 0 0
Phone 0 0
Fax 0 0
Email 0 0
Contact person for public queries
Name 0 0
Dr Nora E Straznicky, PhD MPH
Address 0 0
Country 0 0
Phone 0 0
61 3 8532 1371
Fax 0 0
Email 0 0
nora.straznicky@bakeridi.edu.au
Contact person for scientific queries

Summary results
For IPD and results data, please see https://clinicaltrials.gov/show/NCT01771042