Ramadan fasting in a bus driver with diabetes and stage 3b chronic kidney disease
A 58-year-old man with type 2 diabetes for 12 years attends your family medicine clinic in Assiut two weeks before Ramadan. He works as a school bus driver. His medication is metformin 1 g twice daily, gliclazide 80 mg twice daily, ramipril 10 mg daily, atorvastatin 20 mg at night and aspirin 75 mg daily. BMI is 31 kg/m² and blood pressure 138/84 mmHg. Recent results: HbA1c 8.4%, eGFR 36 mL/min/1.73 m² (CKD-EPI), urine albumin-creatinine ratio 220 mg/g, no retinopathy, no foot ulcer, and no history of hypoglycaemia or ketoacidosis. Fasting where he lives will last about 15 hours, and it will be August. He is determined to fast the whole month and says his late father fasted until he was 80. He has no glucose meter at home and the nearest emergency department is 25 minutes away. He asks whether he can simply skip the morning tablets during the fast.
1. Using a validated risk-stratification tool, classify this patient's fasting risk and explain the factors that drive your classification.
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Use the IDF–DAR risk stratification (or your national adaptation of it), not clinical impression alone.
He falls into the high-risk group; some versions of the tool would place eGFR 30–45 in the very-high-risk band, so check the exact version you use and say which one you are applying.
Drivers of the classification:
- Established CKD, eGFR 36 - reduced renal reserve, reduced clearance of glucose-lowering drugs, and vulnerability to dehydration-mediated acute kidney injury during a 15-hour summer fast.
- Sulfonylurea therapy - gliclazide is a leading cause of fasting-related hypoglycaemia, and hypoglycaemia is the commonest serious complication of Ramadan fasting.
- HbA1c 8.4% - he is above target, so a structured medication change is needed regardless of fasting.
- Long fasting day (~15 h) in August and no home glucose meter.
- 25 minutes from emergency care, and he drives a bus - a hypoglycaemic episode would endanger others.
Equally important is what is absent: no hypoglycaemia in the last 3 months, no ketoacidosis, no advanced macrovascular disease. Fasting is therefore not absolutely prohibited.
The judgment point is that risk stratification is not a veto. It triggers a documented shared decision, an explicit discussion that Islamic law permits the sick not to fast (with qaḍāʾ or fidyah), and - if he still insists - a supervised, pre-agreed plan with clear stop rules.
2. Set out the medication plan you would write for the month of Ramadan, with doses, and justify each change.
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Before Ramadan (start now, 2 weeks ahead):
- Stop gliclazide. Long-acting sulfonylureas cause hypoglycaemia and accumulate in CKD; this is the single highest-yield change.
- Replace with sitagliptin 50 mg once daily at iftar. Dose is adjusted for eGFR 30–45 (25 mg if eGFR falls below 30). It is weight-neutral, causes little hypoglycaemia alone, and is once daily.
- Metformin: reduce to 500 mg at iftar and 500 mg at suhoor (maximum 1 g/day). At eGFR 30–45 the dose must be capped at 1 g/day, and it must be held on any sick day (vomiting, diarrhoea, fever, poor intake) because of the lactic-acidosis and AKI risk during a dehydrated fast.
- Continue ramipril 10 mg, atorvastatin 20 mg and aspirin 75 mg, taken with iftar. Check creatinine and potassium 1–2 weeks after any change; do not stop the ACE inhibitor simply because of fasting.
- If HbA1c remains above 8.5% despite this, add basal insulin (glargine or degludec) at iftar, starting 0.1–0.2 units/kg (about 10 units), titrated on fasting glucose. Warn him that insulin plus fasting requires more monitoring, not less.
Avoid SGLT2 inhibitors as a new start here: minimal glucose lowering at eGFR 36 and a real risk of volume depletion and euglycaemic ketoacidosis during a summer fast.
Write the plan as a dated table with the iftar and suhoor doses, and give him a copy.
3. What self-monitoring, safety advice and follow-up would you arrange, including advice about his work as a driver?
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Monitoring - he must buy or borrow a glucose meter before Ramadan; a plan without home glucose monitoring is not safe.
- Check capillary glucose at pre-suhoor, mid-afternoon, pre-iftar and 2 hours after iftar, plus any time he feels shaky, sweaty or confused.
- Break the fast immediately if glucose is below 3.9 mmol/L (70 mg/dL), above 16.7 mmol/L (300 mg/dL), or if he has symptoms of hypoglycaemia - and treat with 15 g fast-acting carbohydrate, recheck in 15 minutes.
- Stop metformin and seek review if he has vomiting, diarrhoea, or cannot keep fluids down for more than a few hours.
Driving - check glucose before every shift and before driving; carry glucose tablets in the cab; do not drive if glucose is under 5 mmol/L; avoid driving in the late afternoon, when fasting hypoglycaemia risk peaks. Advise him to tell his employer he is fasting.
Lifestyle - slow-release carbohydrate and protein at suhoor, avoid large volumes of sweet drinks and sugary desserts at iftar, keep well hydrated between iftar and suhoor.
Follow-up - telephone review at the end of week 1, clinic review at 2 weeks and at the end of Ramadan, with HbA1c and renal function afterwards. Involve his family in recognizing and treating hypoglycaemia, and document the risk discussion, his informed choice to fast, and the safety net in his file.