Please select the arm or intervention descriptions that belong to the clinical trial below.
Title: Dietary Linoleic Acid for Secondary Prevention of Coronary Heart Disease and Death in the Sydney Heart Study: a Randomized Controlled Dietary Trial
Brief Summary: The substitution of polyunsaturated fatty acids (PUFA) for saturated fatty acids (SFA) is a cornerstone of worldwide dietary advice for coronary heart disease (CHD) risk reduction. However, clinical CHD benefits specific to the omega-6 PUFA linoleic acid (LA), and distinct from omega-3 PUFAs, have not been established. The Sydney Diet-Heart Study (SDHS; 1966-1973) was a randomized controlled secondary CHD prevention trial testing whether selectively increasing omega-6 LA from safflower oil in place of SFA reduced CHD and improved survival. A full analysis of mortality outcomes has not been published. The investigators recovered the original SDHS dataset, which included detailed longitudinal dietary, smoking and coded mortality data, permitting evaluation of smoking relapse rates, and all-cause, CVD and CHD mortality outcomes by nutrient intake and duration of diet exposure. Data recovery also permitted the first complete meta-analysis of LA intervention trials on mortality outcomes.

Objectives are (1) to evaluate whether increasing dietary linoleic acid alters CVD and CHD mortality, and (2) to assess whether changes in smoking relapse rates contribute to observed mortality differences.


Options:
A: Arm Label: Synbiotic; Type: ACTIVE_COMPARATOR; Interventions: Dietary Supplement: Synbiotic | Arm Label: Maltodextrin; Type: PLACEBO_COMPARATOR; Interventions: Dietary Supplement: Maltodextrin | Intervention Type: DIETARY_SUPPLEMENT; Name: Synbiotic; Assigned to Arm(s): Synbiotic | Intervention Type: DIETARY_SUPPLEMENT; Name: Maltodextrin; Assigned to Arm(s): Maltodextrin
B: Arm Label: Lower fat diet; Type: EXPERIMENTAL; Interventions: Behavioral: Weight loss | Arm Label: Lower carbohydrate diet; Type: EXPERIMENTAL; Interventions: Behavioral: Weight loss | Arm Label: Walnut-rich diet; Type: EXPERIMENTAL; Interventions: Behavioral: Weight loss | Intervention Type: BEHAVIORAL; Name: Weight loss; Assigned to Arm(s): Lower carbohydrate diet, Lower fat diet, Walnut-rich diet
C: Arm Label: Safflower oil; Type: EXPERIMENTAL; Interventions: Other: Safflower oil | Arm Label: Control group (no diet instruction); Type: NO_INTERVENTION; Interventions: N/A | Intervention Type: OTHER; Name: Safflower oil; Assigned to Arm(s): Safflower oil
D: Arm Label: Vitamin D + fish oil; Type: ACTIVE_COMPARATOR; Interventions: Dietary Supplement: vitamin D3, Drug: omega-3 fatty acids (fish oil) | Arm Label: Vitamin D + fish oil placebo; Type: ACTIVE_COMPARATOR; Interventions: Dietary Supplement: vitamin D3, Dietary Supplement: Fish oil placebo | Arm Label: Vitamin D placebo + fish oil; Type: ACTIVE_COMPARATOR; Interventions: Drug: omega-3 fatty acids (fish oil), Dietary Supplement: Vitamin D3 placebo | Arm Label: Vitamin D placebo + fish oil placebo; Type: PLACEBO_COMPARATOR; Interventions: Dietary Supplement: Vitamin D3 placebo, Dietary Supplement: Fish oil placebo | Intervention Type: DIETARY_SUPPLEMENT; Name: vitamin D3; Assigned to Arm(s): Vitamin D + fish oil, Vitamin D + fish oil placebo | Intervention Type: DRUG; Name: omega-3 fatty acids (fish oil); Assigned to Arm(s): Vitamin D + fish oil, Vitamin D placebo + fish oil | Intervention Type: DIETARY_SUPPLEMENT; Name: Vitamin D3 placebo; Assigned to Arm(s): Vitamin D placebo + fish oil, Vitamin D placebo + fish oil placebo | Intervention Type: DIETARY_SUPPLEMENT; Name: Fish oil placebo; Assigned to Arm(s): Vitamin D + fish oil placebo, Vitamin D placebo + fish oil placebo

Answer: C