A comparison of glycemic effects of glimepiride, repaglinide, and insulin glargine in type 2 diabetes mellitus during Ramadan fasting

Abstract

Although diabetics may be exempted from Ramadan fasting, many patients still insist on this worship. Aim of the present study is to compare the effects of glimepiride, repaglinide, and insulin glargine in type 2 diabetics during Ramadan fasting on the glucose metabolism. Patients, who were willing to fast, were treated with glimepiride (n = 21), repaglinide (n = 18), and insulin glargine (n = 10). Sixteen non-fasting control type 2 diabetics matched for age, sex, and body mass index were also included. Fasting blood glucose (FBG), post-prandial blood glucose (PBG), HbA1c, and fructosamine as well as lipid metabolism were evaluated in pre-Ramadan, post-Ramadan, and 1-month post-Ramadan time points. There was no significant change from pre-Ramadan in FBG, PBG, and HbA1c variables in fasting diabetics at post-Ramadan and 1-month post-Ramadan. However, PBG was found higher in non-fasting control diabetics at post-Ramadan and 1-month post-Ramadan (p < 0.05 and p < 0.001, respectively). In fructosamine levels, a significant increase was noted both in fasting group and non-fasting group at 1-month post-Ramadan (p < 0.01 for all). However, no significant difference was found in the comparison of the changes in fructosamine levels between fasting group and non-fasting group. Risk of hypoglycemia did not significantly differ between fasting and non-fasting diabetics. There was no significant difference between three drug therapies regarding glucose metabolism and rate of hypoglycemia. No adverse effects on plasma lipids were noted in fasting diabetics. In this fasting sample of patients with type 2 diabetes, glimepiride, repaglinide, and insulin glargine did not produce significant changes in glucose and lipid parameters.

Introduction

Every year, millions of Muslims fast from dawn until dusk during the holy month of Ramadan. During the fast, a Muslim is required to abstain not only from food and drink but also from receiving oral medications. In Islam belief, patients with diabetes mellitus (DM) are only exempted from Ramadan fasting if they are going to be affected adversely by fasting. However, some people refuse to accept this concession [1], [2]. EPIDIAR study reported that 42.8% of patients with type 1 DM and 78.7% of patients with type 2 DM fasted for at least 15 days during Ramadan [3].

During Ramadan fasting, slight decrease in fasting serum glucose may occur in normoglycemic healthy subjects [4]. Most of the previous studies have shown that fasting during Ramadan did not adversely affect glycemic regulation in type 2 diabetics [5], [6], [7], [8]. Moreover, some others have suggested an improved glycemic control [9], [10], [11], [12]. Acute metabolic complications are thought to be important problem for the diabetics during Ramadan. Some studies reported increased frequency of hypoglycemia [3], [5], [13], whereas some others did not [2], [6], [9], [12]. Diabetic ketoacidosis has also been reported during Ramadan fasting [3], [14]. However, Gustaviani et al. reported that Ramadan fasting did not lead to an increased beta hydroxybutirate secretion in type 2 diabetics [11].

There is no consensus about the most appropriate drug therapy for type 2 diabetics during Ramadan. One study recommended glibenclamide for this purpose, but another comparative study considered repaglinide as a better choice than glibenclamide [15], [16]. Sari et al. found both glimepiride and repaglinide to be effective for metabolic control during Ramadan fasting with repaglinide having lower rate of hypoglycemia [6]. Not only oral antidiabetics, but also insulin has been used during Ramadan fasting in some studies [17], [18], [19].

We aimed in this study to compare the effects of glimepiride, repaglinide, and insulin glargine in type 2 diabetics during Ramadan fasting on the glucose metabolism.