The Effect of Curcumin Plus Piperine on Mental Health Status, Sleep Quality, and Anthropometric Indices in Patients with Non-Proliferative Diabetic Retinopathy: A Randomized Double-Blind Placebo-Controlled Trial

Abstract

Background: Diabetic retinopathy (DR) is a significant complication of diabetes that can adversely affect the quality of life and anthropometric indices of individuals. This study aimed to investigate the impact of a combination of curcumin and piperine on mental health status (stress, anxiety, and depression), sleep quality, and anthropometric indices in patients with non-proliferative diabetic retinopathy. Methods: This was a 12-week randomized, placebo-controlled, double-blind, parallel-arm clinical trial. A total of 60 patients with DR, aged 30-65 years, were randomly assigned to two groups. The intervention group received 1010 mg/day of curcumin-piperine (2 tablets/day, each containing 500 mg curcumin and 5 mg piperine) (n = 30), while the placebo group received matched placebo tablets (n = 30). Mental health status was assessed using the modified Depression, Anxiety, and Stress Scale-21 (DASS-21), and sleep quality was evaluated using the Pittsburgh Sleep Quality Index (PSQI). Anthropometric indices, including body mass index (BMI) and waist circumference (WC), were also measured. Results: Twenty-seven patients in the intervention group and 29 patients in the placebo group completed the trial. However, using the intention-to-treat (ITT) method, the analysis was conducted on 60 patients. The curcumin-piperine combination demonstrated significant improvements in sleep quality (-0.91 +/- 1.28 vs. -0.34 +/- 0.95; P = 0.025), depression (-1.61 +/- 2.23 vs. 0.39 +/- 1.61; P < 0.001), anxiety (-1.31 +/- 2.23 vs. 0.32 +/- 1.97; P = 0.005), and stress (-1.54 +/- 1.73 vs. -0.67 +/- 1.09; P = 0.024). Furthermore, it led to reductions in BMI (-0.08 +/- 0.15 vs. 0.01 +/- 0.06; P = 0.003), and WC (-0.35 +/- 1.33 vs. 0.22 +/- 0.57; P = 0.038), compared to the placebo. No adverse effects were reported in response to the intervention. Conclusions: The combination of curcumin and piperine appears to be effective in enhancing mental health status, sleep quality, and anthropometric factors in patients with DR. Further clinical trials are necessary to validate these promising findings. Clinical Trial Registration Number: IRCT, IRCT20201129049534N5. Registered 11 September 2021, https://en.irct.ir/trial/56564