Clinical trial NCT00520819: Oslo Antioxidant Study
Official title: Dietary Antioxidant Intervention in Smoking Middle-Aged and Elderly Men
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: PHASE1
PHASE2
Conditions: Cardiovascular Disease
Keywords: Antioxidants
Phytochemicals
Oxidative stress
Inflammation
Endothelial function
Lead sponsor: University of Oslo
Sponsor class: OTHER
Collaborators: name: Ullevaal University Hospital
First posted: 2007-08-27
Enrollment: 102
Sex: MALE
Minimum age (years): 45
Maximum age (years): 75
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: PREVENTION

Brief summary: The primary objective of this study is to test whether increasing the total intake of antioxidants to middle-aged smoking men increases the antioxidant defence, reduces oxidative damage, and improves biomarkers for oxidative stress.

The secondary objectives is to test whether this strategy improves other cardiovascular risk markers including platelet function, lipid levels, inflammation, and markers of endothelial damage.

Detailed description: In this study men smoking 5 or more cigarettes daily will be invited to participate. We will only include individuals with high cardiovascular risk (men rather than women, smokers rather than nonsmokers, middle-aged to elderly rather than young individuals), in order to recruit people with presumed high oxidative stress who might be most likely to show an effect and benefit from our intervention.

at the time of inclusion, participants will be randomized to three groups; control group, kiwi group or phytochemical group. The kiwi group will consume three kiwis a day, whereas the phytochemical group will consume an array of antioxidant-rich food stuffs. The intervention period is eight weeks.

Blood samples will be collected before and after the intervention period.

Eligibility criteria: Inclusion Criteria:

* Men aged 45-75 years
* Daily smoker of a minimum of 5 cigarettes a day
* BMI \<35 kg/m2 (because of difficulties that may be experienced by morbidly obese individuals in following the diet)
* Stable weight range of 4 kg or less during the previous 12 weeks

Exclusion Criteria:

* Any symptomatic CVD (myocardial infarction, angina pectoris, CABG, PCI, CHF, NYHA class III-IV)
* Diabetes type I or type II taking drugs for diabetes
* Following a vegetarian diet or near-vegetarian diet currently
* Allergy to nuts, kiwi fruits, chocolate, strawberries or tomatoes
* Clinical disorders including gastrointestinal disease impairing compliance with dietary recommendations
* History of serious or unstable medical or psychiatric disorder
* Current use of or need of lipid lowering drug treatment, aspirin or non-steroidal anti-inflammatory drugs (NSAID), according to assessment of the primary clinical investigator. Any "over the counter" headache/ pain or cold remedies taken during the study must not contain aspirin or aspirin like drugs such as ibuprofen. These are classed as and will interfere with platelet function, making them unresponsive for a period of 10-14 days. Paracetamol, however, can be taken as an alternative if required
* History of alcohol/or drug abuse
* Participation in a drug trial during the previous 30 days
* Use of drugs (Xenical, Reductil), nutritional supplements or herbs for weight loss within the 4 weeks prior to visit 2 or participation in an active weight reduction program
* Use of single vitamin or other antioxidants (must be stopped 4 weeks prior to visit 2)
* Individuals judged by the clinical investigator to be unable to follow instructions and procedures of the study.

Primary outcomes:
measure: Biomarkers cardiovascular risk including platelet function, lipid levels, inflammation, and markers of endothelial damage.
timeFrame: 8 weeks
Secondary outcomes:
measure: Biomarkers cardiovascular risk including platelet function, lipid levels, inflammation, and markers of endothelial damage.
timeFrame: 8 weeks
Other outcomes:
Locations:
city: Oslo
country: Norway
facility: Ullevål University Hospital
Study officials:
affiliation: University of Oslo
name: Rune Blomhoff, PhD
role: PRINCIPAL_INVESTIGATOR
affiliation: Ullevaal University Hospital
name: Serena Tonstad, MD
role: PRINCIPAL_INVESTIGATOR
affiliation: University of Oslo
name: Anette Karlsen, MSc
role: PRINCIPAL_INVESTIGATOR
References:
citation: Karlsen A, Svendsen M, Seljeflot I, Sommernes MA, Sexton J, Brevik A, Erlund I, Serafini M, Bastani N, Remberg SF, Borge GI, Carlsen MH, Bohn SK, Myhrstad MC, Dragsted LO, Duttaroy AK, Haffner K, Laake P, Drevon CA, Arnesen H, Collins A, Tonstad S, Blomhoff R. Compliance, tolerability and safety of two antioxidant-rich diets: a randomised controlled trial in male smokers. Br J Nutr. 2011 Aug;106(4):557-71. doi: 10.1017/S0007114511000353.
citation: Bohn SK, Myhrstad MC, Thoresen M, Holden M, Karlsen A, Tunheim SH, Erlund I, Svendsen M, Seljeflot I, Moskaug JO, Duttaroy AK, Laake P, Arnesen H, Tonstad S, Collins A, Drevon CA, Blomhoff R. Blood cell gene expression associated with cellular stress defense is modulated by antioxidant-rich food in a randomised controlled clinical trial of male smokers. BMC Med. 2010 Sep 16;8:54. doi: 10.1186/1741-7015-8-54.