Cardiovascular and Renal Effects of Hibiscus Sabdariffa Linnaeus. in Patients with Diabetic Nephropathy: A Randomized, Double-Blind, Controlled Trial

Background: Hibiscus sabdariffa linnaeus (HSL) is a tropical plant with a high content of anthocyanin, traditionally found to have beneficial biological activities. This randomized, double-blind, placebo-controlled, and parallel trial was conducted to assess some renal and cardiovascular effects of supplementation with HSL in patients with diabetic nephropathy. Methods: The study protocol was completed by 60 patients (38 females and 22 males) who were randomly assigned into the supplemented (SG) and Placebo groups (PG). The SG was treated with 425 mg of HSL twice daily and the PG received the placebo. Anthropometric and dietary information as well as fasting blood and urine samples were collected at the baseline and end of an 8-week intervention period. Results: Compared with the PG, supplementation with HSL significantly reduced systolic blood pressure (P = 0.01) and high-sensitivity C-reactive protein (P = 0.004). A significant increase was observed in total antioxidant capacity levels in the SG (P = 0.03). Moreover, we found a significant reduction in the levels of blood urea nitrogen (P < 0.001), blood creatinine (P = 0.002), urine creatinine (P < 0.001), and urine albumin (P < 0.001) in the SG compared with the PG. However, no significant change was observed in diastolic blood pressure, fasting blood glucose, and glomerular filtration rate following intervention between two groups. Conclusions: HSL supplementation seems to be beneficial in improving the outcomes of patients with diabetic nephropathy; however, no considerable effect was observed on fasting glucose levels. Large-scale trials are needed to better understand its efficiency and safety for long-term use.