Impact of Ramadan Fasting on Glycemic Control in Patients with Diabetes & Coronary Heart Disease
Mohamed  Hassanein, Fauzia Rashid, Mohammed Abdel latif, Alaaeldin  Basheir
Maryam Al Saeed, Elamin Abdelgadir, Sona Abul kheir, Azza Khalifa, Fawzi El tayeb
Fatima Alsayyah, Suzan Jacob , Fatheya Alawadi

Background
Cardiovascular disease is a leading cause of morbidity and mortality in patients with diabetes especially in middle and low-income countries in the world (1) where the Muslims are predominant. Most of Muslims patients with diabetes and CVD elect to fast in Ramadan, but the actual risk in the different subset of patients with CVD is largely unknown. Considering the extended fasting hours theoretically, may increase the possibility of hyperviscosity and thrombosis. This factor along with possible missed or altered timings for essential medicines and occurrence of hypoglycemia can cause deleterious cardiovascular effects. Only a few studies are done in patients with diabetes and Coronary heart disease (CHD) with an aim to observe any adverse cardiovascular outcome in Ramadan (2,3,4). To the best of our knowledge, no study is done so far to monitor the effect of Ramadan fasting on glycemic control and frequency of hypoglycemia in these high-risk patients with the use of continuous glucose monitor(CGM) and to correlate it with an adverse cardiovascular event in Ramadan fasting.
Aim
We sought to understand the safety of fasting in CHD patients with diabetes insisting on fasting Ramadan. We conducted this prospective study in a tertiary care hospital in Dubai during Ramadan 2016 that from June 6th till July 5th.
 PATIENTS AND METHODS
Patient with T2DM with stable known CHD since last three months and insisted on fasting despite advice against it was randomly selected from endocrine and cardiology clinic 1 to 2 months before Ramadan, counselled, and asked to sign an informed consent. Patients with the concurrent renal disease or any recent hospitalisation in last 3 months were excluded. All the patients received 90 minutes’ session for Ramadan-focused education. The Libre flash sensor insertion is done for continuous glucose monitoring. Their biophysical and biochemical profile was collected 2 to 4 weeks before and after Ramadan. We recorded DM or CVD-related emergency visit or hospitalisation, change in BMI, systolic and diastolic BP, HBA1c, and frequency of hypoglycemia during Ramadan fasting and not -fasting period. 
All the quantitative values are described as mean, and analysis of CGM data is shown in frequencies.

RESULTS
We recruited 26 patients,1 patient did not fast in Ramadan after signing consent as scheduled for surgery and 4 patients did not complete the protocol. There were 21 final participants,15 males and 6 females with mean age of 58 years (range 34-71). Anti- diabetic regime included basal or basal bolus or premixed insulins with or without combination with other oral agents. An average number of days fasting were 28.  90% patients (n=18) completed >20 days fasting. 19% patients (n=4) broke their fast. 47% patients (n=10) experienced symptomatic hypoglycemia. However none of them reported severe hypoglycemia, one patient visited emergency department with dyspnea after Ramadan. 
Most patients have 3 sensors attached to them with average 3 weeks during Ramadan and 3 weeks outside Ramadan (Sha'ban and shawal). The sensor data showed peak mean glucose during Ramadan was 281mg/dl (191-393) and none- Ramadan was 275 (131-444) with mean HBA1c of 7.9% and 7.3% respectively. Total 67 episodes of hypoglycemia with lowest mean glucose of 60mg/dl (40-121) recorded during Ramadan while non- Ramadan period 24 hypoglycemic events and lowest mean glucose value was 67mg/dl (40-142). The average duration for hypoglycemia was 118 minutes (30-340) in Ramadan and 49 minutes (30-184) in non- Ramadan. The mean glucose value below 60mg/dl recorded in 78% of patients in Ramadan and 40% of patients during non -Ramadan.
During fasting Ramadan 76% patients had 1-10 and 5% had more than 10 episodes of hypoglycemia however 51% had experienced 1 to 10 episodes, and 49% of them never had any hypoglycemia recorded in non- fasting state. 

Conclusion: This is first ever to study using CGM in high-risk CHD patients to objectively assess the glycemic changes and frequency of hypoglycemia and its correlation with any adverse CVD effect. Patients had 2.7 times higher incidence of hypoglycemia that is more marked and prolonged during fasting compared to non-fasting. No significant alteration was seen in BMI, SBP and DBP, HBA1c, lipid profile and hepatic functions. Studies with larger sample size needed for further validation of these findings.

References
1.	International Diabetes Federation. Diabetes and cardiovascular disease. Brussels, Belgium: International Diabetes Federation, 2016. www.idf.org/cvd 
2.	Chamsi-Pasha M, Chamsi-Pasha H. The cardiac patient in Ramadan. Avicenna J Med. 2016;6(2):33. 
3.	Mousavi M, Mirkarimi S, Rahmani G, Hosseinzadeh E, Salahi N. Ramadan fast in patients with coronary artery disease. Iran Red Crescent Med J. 2014 Dec;16(12):e7887. 
4.	Salim I, Al Suwaidi J, Ghadban W, Alkilani H, Salam AM. Impact of religious Ramadan fasting on cardiovascular disease: a systematic review of the literature. Curr Med Res Opin. 2013 Apr;29(4):343–54.

Impact of Ramadan fasting on glycemic control in patients with diabetes and coronary heart disease