See this link for Quality Prescribing for Diabetes – A guide for improvement

What is the optimal level of blood glucose control?

There are some important principles to consider when managing diabetes in people who are older and/or frailer,and especially when they have co-morbidities. Tight glycaemic control (HbA1_c <53mmol/mol) may be appropriate in patients who are relatively healthy, with long life expectancy, and will live long enough to derive the benefits, such as reducing microvascular events. However, intensive glycaemic control strategies markedly increase the risk of hypoglycaemia. In turn hypoglycaemia has been associated with poor outcomes such as increased mortality, cardiovascular disease, falls and accidents.²³  There is likely to be a time for each individual when the harm caused by managing glycaemic control starts to outweigh any potential benefits. The challenge is to identify when this happens, which is why these evidence based factors below should be considered at patient review.

The Hemoglobin A_1c Targets for Glycaemic Control With Pharmacologic Therapy for Nonpregnant Adults With Type 2 Diabetes Mellitus provides clear advice and direction informed by rigorous evidence review and a consensus of key guidelines, including SIGN 116.²³

• Guidance Statement 1: Clinicians should personalize goals for glycaemic control.

The fine balance of benefits and risks of different intensities of glycaemic control are affected by many factors. The individuals glycaemic target should consider the risk of hypoglycaemia, weight gain and other adverse drug events, as well as the patients age, life expectancy, comorbidities, functional and cognitive impairment, fall risk, ability to adhere, medication burden and cost

• Guidance Statement 2: Clinicians should aim to achieve an HbA_1c level between 53 and 64 mmol/mol in most patients with type 2 diabetes.

Trials show that treating to targets of 53 or less compared with targets of around 64 did not reduce death or macrovascular events over 10 years of treatment, but did result in harm, including hypoglycaemia. Risk of harm was greatest for older patients with comorbidities.

• Guidance Statement 3: Clinicians should consider deintensifying pharmacologic therapy in patients with type 2 diabetes who achieve HbA_1c less than 48 mmol/mol.

The ACCORD trial, which targeted treatment of HbA_1c to less than 48 mmol/mol  was discontinued early due to an increase in all-cause and cardiovascular mortality and severe hypoglycaemic events

• Guidance Statement 4: Clinicians should treat patients with type 2 diabetes to minimise symptoms related to hyperglycaemia and avoid targeting an HbA_1c level in patients with a life expectancy less than 10 years due to advanced age (80 years or older), residence in a nursing home, or chronic conditions (such as dementia, cancer, end-stage kidney disease, or severe chronic obstructive pulmonary disease or congestive heart failure because the harms outweigh the benefits in this population.

For these populations the use of sulfonylureas and insulin carry the greatest risk of harm.

For all patients with type 2 diabetes clinicians should provide counselling and emphasise the importance of lifestyle interventions, including exercise, dietary changes, and weight loss, to achieve good glycaemic control. Smoking cessation, adequate blood pressure control, and lipid management are also indicated in patients with type 2 diabetes and, for many patients, may take priority over achieving glycaemic control, especially for preventing macrovascular complications.

There remains clear evidence of benefit from tight glycaemic control in younger people (<55 years) with type 2 diabetes. The clinical benefits take ten years to be realised, but once established are shown to last a further seven years, even if the tight glycaemic control is not maintained, which is termed the ‘Legacy Effect’. Each individual will reach a tipping point when tight glycaemic control does more harm than good, and it is these patients that should be targeted for review.