Sympathetic Activity in Individuals With the Metabolic Syndrome: Benefits of Lifestyle Interventions

NCT00163943 | Unknown

• 1 other identifier: 7/05
• Study Type: interventional
• Target: 66
• Locations: 1 country
• Sites: 1

Brief Summary

An abdominal distribution of fat is associated with the greatest heart disease risk, because commonly, several risk factors of metabolic origin (high blood pressure, unfavourable cholesterol profile, elevated blood sugar, impaired insulin action) cluster in these individuals. When this occurs the condition is called the 'metabolic syndrome' (MetS). The cause of the MetS is yet to be fully elucidated. Increased activity of the nervous system resulting in enhanced release of the stress hormone 'norepinephrine', may be one mechanism by which adverse cardiovascular and metabolic sequelae of the MetS might be mediated. Dietary weight loss, and exercise are first-line treatments for the MetS and provide an opportunity to prevent or delay the development of type 2 diabetes and heart disease in this high risk group. However, there is a paucity of data regarding the effects of these lifestyle factors on the nervous system. Furthermore, it is also unknown whether active weight loss ('negative energy balance') or a stable lower weight (weight loss maintenance) is more important in modifying MetS components and nervous system activity. The aims of the proposed project are:

1. 1.To determine whether dietary weight loss in combination with aerobic exercise is more beneficial than dietary weight loss alone in reducing nervous system activity and improving metabolic and cardiovascular parameters in middle-aged men and women with abdominal obesity and the MetS.
2. 2.To determine whether weight loss maintenance four months after active weight loss is associated with a preservation of clinical benefits.
3. 3.To study biological determinants of successful weight loss and weight loss maintenance.

Conditions

Metabolic Syndrome X

Keywords

Metabolic syndrome; Sympathetic nervous system activity; Insulin sensitivity; weight loss; aerobic exercise

Outcome Measures

Primary Outcomes (2)

• Whole-body sympathetic activity

• Muscle sympathetic activity

Secondary Outcomes (6)

• Insulin sensitivity

• Lipid profile

• Adipocytokines

• Blood pressure

• Baroreflex function

Interventions

Dietary weight loss +/- aerobic exercise BEHAVIORAL

Eligibility Criteria

• Age: 45 Years - 65 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Sixty six (33 male and 33 postmenopausal female) weight-stable (body mass index 26 to 39 kg/m2), sedentary, non-smoking subjects, aged 45 to 65 years will be recruited on the basis of having \> 3 indices of the MetS as defined by Adult Treatment Panel (ATP) III criteria:
• waist circumference \> 102 cm for men and \> 88 cm for women;
• fasting plasma glucose level \> 6.1 mmol/L, but nondiabetic (\< 7.1 mmol/L);
• fasting plasma triglyceride level \> 1.69 mmol/L;
• plasma high-density lipoprotein (HDL) level \< 1.04 mmol/L (males) and \< 1.29 mmol/L (females);
• supine resting blood pressure \> 130/85 mmHg and \< 165/105 mmHg, at least 4 weeks off blood pressure lowering medications.

You may not qualify if:

• A history of diabetes, secondary hypertension, sleep apnoea, cardiovascular, cerebrovascular, renal, liver, or thyroid disease
• Inability to cease medications which may affect measured parameters
• Inability or contraindication to exercise

Sponsors & Collaborators

• Bayside Health: lead

Study Sites (1)

Baker Heart Research Institute

Melbourne, Victoria, 8008, Australia

RECRUITING

Related Publications (2)

• Khan AA, Mundra PA, Straznicky NE, Nestel PJ, Wong G, Tan R, Huynh K, Ng TW, Mellett NA, Weir JM, Barlow CK, Alshehry ZH, Lambert GW, Kingwell BA, Meikle PJ. Weight Loss and Exercise Alter the High-Density Lipoprotein Lipidome and Improve High-Density Lipoprotein Functionality in Metabolic Syndrome. Arterioscler Thromb Vasc Biol. 2018 Feb;38(2):438-447. doi: 10.1161/ATVBAHA.117.310212. Epub 2017 Dec 28.

  PMID: 29284607 DERIVED

• Nestel PJ, Straznicky N, Mellett NA, Wong G, De Souza DP, Tull DL, Barlow CK, Grima MT, Meikle PJ. Specific plasma lipid classes and phospholipid fatty acids indicative of dairy food consumption associate with insulin sensitivity. Am J Clin Nutr. 2014 Jan;99(1):46-53. doi: 10.3945/ajcn.113.071712. Epub 2013 Oct 23.

  PMID: 24153346 DERIVED

MeSH Terms

Conditions

Metabolic Syndrome; Insulin Resistance; Weight Loss

Condition Hierarchy (Ancestors)

Hyperinsulinism; Glucose Metabolism Disorders; Metabolic Diseases; Nutritional and Metabolic Diseases; Body Weight Changes; Body Weight; Signs and Symptoms; Pathological Conditions, Signs and Symptoms

Study Officials

• Nora E Straznicky, BPharm, PhD, MPH

  Baker Heart Research Institute

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Nora E Straznicky, BPharm, PhD, MPH

CONTACT

61 3 8532 1371; Nora.Straznicky@baker.edu.au

Elisabeth A Lambert, Bsc, MSc, PhD

CONTACT

61 8532 1345; Elisabeth.Lambert@baker.edu.au

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER GOV

Study Record Dates

• First Submitted: September 12, 2005
• First Posted: September 14, 2005
• Study Start: April 1, 2005
• Study Completion: December 1, 2007
• Last Updated: August 1, 2007

Record last verified: 2005-09

Locations

AU (1)