Effect of nano-curcumin supplementation on cardiometabolic risk factors, physical and psychological quality of life, and depression in patients with coronary slow flow phenomenon: a randomized double-blind clinical trial

Background Extensive evidence has suggested the cardio-protective properties of the polyphenol curcumin. The aim of this study was to investigate the effects of a highly bioavailable curcumin supplement on cardiometabolic risk factors, health-related quality of life, and depression in patients with coronary slow flow phenomenon (CSFP). Methods This randomized double-blind placebo-controlled clinical trial was conducted in 42 patients with CSFP (age 35-70 years, 25 <= body mass index < 40 kg/m(2)). Patients received either 80 mg/day nano-curcumin or placebo for 12 weeks. Serum levels of visfatin, high-sensitivity C-reactive protein (hs-CRP), and glycemic indices were measured before and after the intervention. The short form 36-item quality of life (SF-36) and Beck's Depression Inventory-II (BDI-II) questionnaires were assessed, as well. Results No significant improvements were observed in circulating hs-CRP and visfatin following the intervention. A significant increase was observed in pre- to post-fasting blood glucose (- 0.9 +/- 12.2 vs. 7.7 +/- 12.4 mg/dl, p = 0.02) and hemoglobin A1C (- 0.1 +/- 0.8 vs. 0.5 +/- 0.8%, p = 0.04) levels, in the placebo compared with the intervention group. Physical (8.2 +/- 8.1 vs. - 1.2 +/- 6.5, p < 0.001) and mental (6.8 +/- 11.8 vs. - 1.1 +/- 10.4, p = 0.02) component summary scores were significantly improved in the nano-curcumin than the placebo group. Additionally, the number of patients with lower degrees of depression was significantly better in the intervention than the placebo group following the supplementation (p = 0.046). Conclusion Curcumin supplementation prevented deterioration of glycemic control and improved physical and psychological quality of life and depression in patients with CSFP. Trial registration Iranian Registry of Clinical Trials (IRCT20131125015536N8), June 19, 2019.