Clinical trial NCT03350568: Dietary Antioxidants and Chronic Diseases-The Swedish National March Cohort
Official title: Study 1: Dietary Non Enzymatic Antioxidant Capacity and the Risk of Myocardial Infarction - The Swedish National March Cohort; Study 2: Dietary Total Antioxidant Capacity and Risk of Osteoarthritis in the Swedish National March Cohort
Study type: OBSERVATIONAL
Overall status: COMPLETED
Conditions: Myocardial Infarction
Diet
Osteoarthritis
Keywords: Antioxidants
Oxidative Stress
Atherosclerosis
Epidemiology
Lead sponsor: Karolinska Institutet
Sponsor class: OTHER
First posted: 2017-11-22
Enrollment: 43880
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Observational model: COHORT
Time perspective: PROSPECTIVE
Sampling method: NON_PROBABILITY_SAMPLE
Study population: Study 1: Study population (n=34,543) was between the age of 18-94 years and free from cancer (except non-melanoma skin cancer) or any cardiovascular disease before the beginning of follow up.

Study 2: Study population (n=29,188) was between the age of 40-94 years and free from osteoarthritis, bone cancer or -metastases , joint injury, or any arthropathy disease other than.

Brief summary: Dietary antioxidants might protect from the development of chronic diseases by reducing levels of oxidative stress. The investigators therefore investigated the effect of dietary Non Enzymatic Antioxidant Capacity, which measures interactions between antioxidants in the whole diet, on the risk of 1) myocardial infarction and 2) osteoarthritis.

Detailed description: Aim: Among an initial sample of 43,880 men and women who participated in the Swedish National March Cohort in 1997 the investigators aimed to investigate the effect of dietary Non Enzymatic Antioxidant Capacity (NEAC), assessed by a validated food frequency questionnaire at baseline, on the risk of 1) myocardial infarction and 2) osteoarthritis.

Identification of cases: Incident cases of myocardial infarction (ICD-10 code I21) and osteoarthritis (ICD-10 M15-19) were identified through exact linkages to the Swedish registries of population, migration, death, cancer, and inpatient care, using the national registration numbers as identifiers.

Main methods: The investigators fitted Cox proportional hazards regression models with age as underlying time scale to estimate hazard ratios (HR) with 95% confidence intervals (95% CI) for each outcome of interest at different levels of dietary NEAC. The investigators fitted multiple imputation models based on chained equations to address missingness of confounder variables.

Eligibility criteria: Exclusion Criteria Study 1:

* Incorrect national registration number
* Subjects who were \<18 years
* Emigration before beginning of follow-up
* Death before beginning of follow-up
* Cancer diagnosis
* Any cardiovascular disease
* Extreme energy intake

Exclusion Criteria Study 2:

* Incorrect national registration number
* Subjects who were \<40 years
* Emigration before beginning of follow-up
* Death before beginning of follow-up
* Osteoarthritis diagnosis
* Bone cancer- or metastases
* Joint injury or any arthropathy disease other than osteoarthritis
* Extreme energy intake

Primary outcomes:
measure: Myocardial Infarction
timeFrame: October 1, 1997-December 31, 2010
measure: Osteoarthritis
timeFrame: October 1, 1997-December 31, 2010
Secondary outcomes:
Other outcomes:
Locations:
city: Stockholm
country: Sweden
facility: Karolinska Institutet
Study officials:
affiliation: Department of Medicine, Clinical Epidemiology, Karolinska Institutet; Department of Medicine, Clinic of Endocrinology, Karolinska University Hospital
name: Ylva Trolle Lagerros, MD, PhD
role: PRINCIPAL_INVESTIGATOR
References: