A 76-year-old man with type 2 diabetes, long-standing hypertension and coronary artery disease is reviewed. He has symptomatic hypoglycaemia on his current basal-bolus insulin regimen. His most recent HbA1c is 6.4%. He is independent but has mild cognitive impairment and stage 3 chronic kidney disease. According to Diabetes Canada glycaemic target guidance, what is the most appropriate HbA1c target for this patient?