Impact of religious Ramadan fasting on cardiovascular disease: a systematic review of the literature

Background: Fasting during the month of Ramadan is a religious obligation that is practiced by millions of people around the world yet there is no clear scientific consensus on its effects on cardiovascular disease. This study was performed to inform physicians as well as patients of evidence based recommendations on this subject. Aim: The study was undertaken to assess: (1) any alteration in the incidence of acute cardiac illness during Ramadan fasting; (2) whether fasting during the month of Ramadan alters the clinical status of patients with stable cardiac disease; and (3) the impact of Ramadan fasting on cardiovascular risk factors in normal subjects, in patients with stable cardiac disease, metabolic syndrome, dyslipidemia, type 2 diabetes and systemic hypertension. Study design: Systematic review of the literature. Method: A Medline search of the English literature published between January 1980 and September 2012. Results: The incidence of acute cardiac illness during Ramadan fasting was similar to non-fasting days, although the timing of symptom onset may be different, with significant increase in events during the period of 'breaking fast' when compared to non-fasting days. The majority of patients with stable cardiac illness can undergo Ramadan fasting without any clinical deterioration. Body mass index, lipid profile, and blood pressure showed significant improvement in normal healthy subjects, patients with stable cardiac illness, metabolic syndrome, dyslipidemia and hypertension during Ramadan fasting. The lipid profile of diabetic patients deteriorated significantly during Ramadan fasting. Conclusions: Ramadan fasting is not associated with any change in incidence of acute cardiac illness and the majority of cardiac patients can fast without any difficulty. Improvement in lipid profile, especially 30% to 40% increment in high-density lipoprotein, as reported in some studies, appear promising. Diabetic patients should be carefully monitored during Ramadan fasting.