Fasting during the Muslim holy month of Ramadan is one of the five pillars of Islam for all healthy adult Muslims. The fast entails abstinence from eating and drinking from dawn to sunset for a whole lunar month (29 or 30 days). There are no restrictions on food or fluid intake between sunset (iftar) and early dawn (sohour) (1). The main meal, iftar, is taken at sunset and is usually a heavy meal served with deeply fried food and dessert. The other meal, sohour, which is taken before sunrise is normally lighter and is primarily composed of complex carbohydrate (2).

Children, the elderly, travelers, pregnant or nursing women, and sick individuals including those with diabetes mellitus, are exempted from fasting. However, many Muslims, both adults and children, including those with diabetes mellitus opt to undertake Ramadan fasting (RF) even when religiously not required, for cultural, social and personal reasons (3). Fasting in people with diabetes mellitus has certain risks including susceptibility to hyperglycaemia after excessive consumption of sweet and fried foods during and after iftar, risk of diabetic ketoacidosis (DKA), and hypoglycaemia (4, 5).

Management of type 1 diabetes mellitus (T1DM) among children and adolescents is a challenge, even outside RF periods (6). However, children and adolescents with T1DM are often keen to fast during Ramadan and are able to do so for a significant number of days (6). Amongst users of continuous subcutaneous insulin infusion (CSII) or multiple daily insulin injections (MDI), the main treatment regimens used for older children and adolescents with T1DM, reports indicate no significant difference in glycaemic control with “reasonable risk” of hypoglycaemia and hyperglycaemia (7, 8).

The United Arab Emirates (UAE) has one of the world's highest prevalence rates of diabetes mellitus at 16.3% according to the report of International Diabetes Federation (IDF) in 2019 (7). There are over 1 million people living with diabetes mellitus in the UAE, placing the country in the 15th place worldwide for age-adjusted comparative diabetes mellitus prevalence (9). Studies further point out that the incidence of diabetes mellitus in the UAE is rising at a faster rate than both the MENA (Middle East and Northern Africa) region and the rest of the world (10). Risk factors including rapid economic growth, sedentary lifestyles and unhealthy diets are characteristic to the UAE, and it is expected that there will be 2.2 million individuals with diabetes mellitus in the country by 2040 (7). The incidence of T1DM in the UAE has also risen, making it one of the countries with higher prevalence worldwide (11). In 2019, the new cases were estimated at 20.8 per 1,000 in children and adolescents aged 10–19 years old (12).

Over the last few years, several studies have investigated diabetes mellitus outcomes with RF in adults; studies in the pediatric population in this context have been more limited. This often poses challenges to health care providers in providing medical advice to patients of this age group on the feasibility of RF partly because little is known about the safety or metabolic effects of fasting in this group of patients (13).

The current cohort study investigates the outcomes of RF using MDI and CSII to assess patterns of glycaemic control and severity of complications during RF amongst older children and adolescents with T1DM seen at the Imperial College London Diabetes mellitus Center (ICLDC), UAE. The effects of dose adjustment, health professional team and parental support on safety and glycaemic outcomes in children and adolescents with T1DM during Ramadan were also investigated.

Forty-seven patients signified intention to fast during Ramadan; data of five (11%) patients were excluded in the analyses because of fasting plans withdrawal. Forty-two (89%) patients were included in the study; fasting days of 22 ± 9 days during Ramadan. All patients' pubertal stage was within normal range for age based on routine clinical assessment. Baseline characteristics of the study cohort are summarized in Table 1. Majority (46.8%) of the participants used flash glucose monitoring FGM flash glucose monitoring (Freestyle Libre) as their glucose monitoring system (36.2% Enlite, 14.9% Accu-chek).

For all participants (n = 42), there was no statistically significant difference in mean blood glucose levels before- (226.5 ± 54.6 mg/dL), during- (226.5 ± 54.6 mg/dL), and after- (225.7 ± 58.8 mg/dL) Ramadan [one-way ANOVA; F_{(2, 80)} = 1.600, p = 0.208; Figure 2]. HbA1c levels (9.0 ± 1.7 vs. 8.7 ± 1.3) and weight (53.3 ± 18.0 vs. 54.9 ± 19.3) before and after Ramadan did not change significantly compared to baseline (paired t-test; p = 0.02 and p = 0.08, respectively).

In the MDI group, there was no significant difference in paired p-values for before- and during-Ramadan (p = 0.132), before- and after-Ramadan (p = 0.865), and during- and after-Ramadan blood glucose levels; similarly, no statistically significant difference was found for the CSII group (p = 0.957, p = 0.964, p = 0.225, respectively). Between the MDI and CSII groups, there was no significant difference in unpaired p-values for before- and during-Ramadan (p = 0.368), before- and after-Ramadan (p = 0.872), and during- and after-Ramadan (p = 0.434) (Table 2).

In addition, between the two groups, there was no significant difference in fasting days (p = 0.49), HbA1c levels (p = 0.24), and weight (p = 0.11) after Ramadan; as well as reported frequencies of hypoglycaemia episodes (p = 0.98) and DKA (p = 0.37) during Ramadan (Table 3). More than half (57%) of the patients and their families noted dose adjustment as the main support during the fast, followed by parents' support (45%). All (100%) of the patients who completed the fast were willing to fast in the next Ramadan.

Previous studies have shown that effective counseling before RF delivered by health care providers reduces the incidence of hypoglycaemia (17). Patient education before Ramadan provides a platform to remind patients about the importance of diet, exercise, dose adjustment and that regular glucose monitoring is vital to avoid complications while reassuring them that this does not invalidate the fast (9). Patient education is certainly a cornerstone of Ramadan diabetes mellitus management (18), and is stringently applied in the ICLDC pediatric clinic. Patients are instructed that the first day of Ramadan is the most important day to carefully assess glycaemic control as it gives a provisional prediction of glucose excursions in the upcoming month of fasting. Other topics discussed during before Ramadan education sessions include prior fasting experiences, ways to reduce blood glucose levels fluctuations and complications, how to improve self-reliance and confidence, tailored change plan for dose and pump programming adjustments, and more importantly, informed decision-making about fasting. This education plan offers an imperative opportunity to allow those who wish to fast to do so more safely (9).

The recent 2021 recommendations of the (IDF)/Diabetes and Ramadan (DAR) Alliance (19) discourage children and adolescents with T1DM to practice RF. However, many children and adolescents choose to fast (20), presenting a challenge to health care providers. Children and adolescents can be even more eager to fast compared to their adult family members, a phenomenon related to self-esteem and happiness (21, 22). The Islamic norm on RF in this age group is for Muslim children to fast when specific features of puberty are attained (21, 23). The challenge to physicians is primarily in providing intensive pre-fasting education and emphasizing the need for closer blood glucose monitoring during the fast (2).

Although several studies have investigated different aspects of RF in individuals with diabetes mellitus, most exclude children and adolescents. The issues and challenges in this age group are, in fact, often more pronounced and, in some ways, different. During childhood, the responsibility on managing diabetes mellitus falls on the parents who usually decide on whether to proceed with the full RF for their children. The parents try to monitor blood glucose fluctuations and make adjustments of insulin doses with primary aim of avoiding hypoglycaemia. As a result, exaggerated hyperglycaemic response may happen and is more pronounced at the time when fasting is broken (iftar). In adolescents, the problems can be even more challenging because at this age, they prefer to take charge of their disease management and are often less predictable with their dietary and medication compliance (20, 24).

International guidelines on diabetes mellitus management for adults during RF confirm that poor control of diabetes mellitus is considered as one of the main contraindications for fasting (17, 25–27). Well-controlled children and adolescents with T1DM are expected to have less complications making RF feasible for them (28). Studies on the effects of RF in children with diabetes mellitus have been few and results have been inconsistent. While some studies showed stable HbA1c before and after Ramadan (22, 29), some other studies showed deterioration of glycaemic control in the form of elevated HbA1c after Ramadan (24, 30). Bin-Abbas et al., suggested that fasting can be safe for well-controlled adolescents with T1DM who are using CGM devices (29), whereas other investigators have asserted that RF might predispose to acute complication in patients of this age group (30, 31). Further diabetes mellitus management challenges exist for poorly controlled children and adolescents with T1DM who fast against medical advice, as in some patients in the cohort. Study showed no significant differences were observed on mean blood glucose levels, HbA1c, and weight before- and after-Ramadan. These results need to be interpreted with caution. Our previous studies in adults indicate that HbA1c is a poor indicator of changes in glycaemic control when comparing a one-month time window such as Ramadan with another. A similar principle may be applicable in the pediatric population and that a CGM/FGM-derived glucose management indicator (GMI, or estimated HbA1c) may be better suited for looking at any such potential change more closely. Furthermore, adult studies show definite differences in glucose profiles of individuals with diabetes mellitus during Ramadan when compared with non-Ramadan periods, with a significant glucose excursion at iftar time which is more pronounced in people with poorer glycaemic control (32).

The results of this study also support previous studies which show that outcomes of CGM/FGM use with both MDI and CSII during RF are not significantly different. A recent similar study in Kuwait (33) is also in agreement with the present study that intensive monitoring along with patients' education before Ramadan are crucial for safe RF in the cohort. Another study conducted in Saudi Arabia reported that children and adolescents with T1DM using FGM could fast Ramadan without severe hypoglycaemia or DKA risks (34).

This study sheds light on the practice of RF in children and adolescents which is often a personal decision supported by family, social and cultural values which may not necessarily be supported by religious recommendations. The challenge to healthcare professionals is significant; and this study shows the impact of a modified CHOICE before Ramadan education programme (16) guided by the IDF-DAR recommendations (19) in addition to the expertise of a diverse health care team. More evidence from future studies is needed to improve medical guidelines and help health care providers take proper clinical decisions.

The raw data supporting the conclusions of this article will be made available by the authors, without undue reservation.

Ethical review and approval was not required for the study on human participants in accordance with the local legislation and institutional requirements. Written general consent including use of data for research use was provided by the participants and/or participants' parents/legal guardian upon patient registration in the centre.

TM: study concept, data acquisition, and manuscript editing. EF: statistical analyses and manuscript writing. RH: data interpretation and manuscript writing. NL: study design, data interpretation, and manuscript editing. All authors contributed to the article and approved the submitted version.

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

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