The effects of Ramadan fasting on endothelial function in patients with cardiovascular diseases

BACKGROUND/OBJECTIVES: Endothelial dysfunction, which can be manifested by loss of nitric oxide bioavailability, is an increasingly recognized cause of cardiovascular diseases. Previous studies showed that diets affect endothelial function and modify cardiovascular risks. This study aimed to assess the effects of Ramadan fasting, as a diet intervention, on endothelial function. SUBJECTS/METHODS: The study population consisted of 21 male patients (mean age: 52 +/- 9 years) with cardiovascular risks (coronary artery disease, cerebrovascular or peripheral arterial diseases). The biochemical variables in serum of patients were measured 2 days before and after Ramadan fasting. The levels of asymmetric dimethylarginine (ADMA) and vascular endothelial growth factor (VEGF) were evaluated using the enzyme-linked immunosorbent assay. Nitric oxide (NO) and Malondialdehyde (MDA) levels were measured by the Griess and thiobarbituric acid reaction substances assay, respectively. RESULTS: NO levels in patients after Ramadan fasting were significantly higher compared with the baseline value (85.1 +/- 11.54 vs 75.8 +/- 10.7 mu mol/l) (P < 0.05). Post-Ramadan levels of ADMA decreased significantly in comparison with pre-Ramadan levels (802.6 +/- 60.9 vs 837.6 +/- 51.0 nmol/l) (P < 0.05). In addition, the levels of VEGF and MDA changed during Ramadan fasting, but these changes were not statistically significant (228.1 +/- 27.1 vs 222.7 +/- 22.9 pg/ml and 3.2 +/- 0.7 vs 3.6 +/- 1.1 mu mol/l, respectively). CONCLUSIONS: Ramadan fasting may have beneficial effects on endothelial function and can modulate cardiovascular risks. Further studies are needed to confirm the clinical significance of Ramadan fasting on cardiovascular health.