The effects of black seed supplementation on metabolic profiles in type 2 diabetic patients with coronary heart disease

Objective: The aim of this study is to determine the effects of black seed supplementation on metabolic profiles in type 2 diabetic patients with coronary heart disease (CHD).

Study design: Randomized double-blind placebo-controlled trial. Patients will be assigned into two groups to receive black seed supplements (n=35) or placebo (n=35).

Among patients with coronary heart disease referred to cardiology clinic, 70 patients will be selected according to inclusion and exclusion criteria. Participants, investigators or the assessors of the outcomes are unaware of the study groups. Supplements and placebos are similar in shape and size. Fasting blood samples will be taken at baseline and 24 weeks after the intervention. Intervention period: 24 weeks.

Inclusion Criteria: Patients aged 45-85 years diagnosed with type 2 diabetes and coronary heart disease. Non-inclusion criteria: Patients with thyroid disorders, severe renal insufficiency, hepatic failure, those experiencing an acute myocardial infarction within the past 3 months, patients undergoing cardiac surgery within the past 3 months.

Intervention group: Four N. Sativa containing capsules (Barij Essence, Kashan, Iran), 500 mg each capsule, daily, for 24 weeks orally. Control group: Placebo (Barij Essence, Kashan, Iran) daily for 24 weeks orally.

Outcomes: Markers of insulin metabolism (primary outcomes) and lipid profiles, inflammatory markers, and oxidative stress parameters (secondary outcomes) will be quantified at study baseline and end-of-trial

Patients will be randomly assigned into two groups. A randomization list will be generated from 1 to 70 by SPSS software (version 16) and participants will be randomly assigned into each intervention group by their numbers. The block randomization technique with 1:1 ratio will be used to achieve balanced group sizes.

Randomization and allocation will be concealed from the researchers and participants until the final analyses are completed. Another person at the Cardiology clinic, who is not involved in the trial and not aware of random sequences, will be assigned the participants to the numbered bottles of supplements. Supplements and placebo are in the same packaging at the Barij Essence pharmaceutical company. Only the code is written on the packages. Patients and researcher do not know the type of drug and after analyzing the data, packet codes are decoded.