Choosing targets for glycaemia, blood pressure and low-density lipoprotein cholesterol in elderly individuals with diabetes mellitus

Diabetes mellitus in the 'elderly' poses unique management challenges that contribute to conflicting priorities. Individualized management requires taking into account each patient's medical history, functional ability, home care situation, life expectancy and his/her health beliefs; individuals value trade-offs (e.g. quantity versus quality of life, and side effects as well as risks versus long-term benefits) differently. Moreover, this decision making relies on imperfect evidence. Target goals for three intermediate outcomes - glycaemic control (glycosylated haemoglobin [HbA(1c)]), blood pressure control and lipid control (low-density lipoprotein cholesterol [LDL-C]) - help keep management on track. Of these, glycaemic control is usually the most complex. Glycaemic control alleviates symptoms of hyperglycaemia and can improve micro- and macrovascular outcomes. Tight glycaemic control (HbA(1c) <7%) clearly improves microvascular outcomes. However, hypoglycaemia and polypharmacy are the main drawbacks of tight control. Factors that influence the benefits and drawbacks include age, longevity and co-morbidities, including the geriatric 'syndromes' of frailty and falls. We favour the explicit risk-stratified approach of the Department of Veterans Affairs/Department of Defense (VA/DoD) guidelines, which set HbA(1c) target ranges based on physiological age or the presence/severity of major co-morbidities and microvascular complications. There are clear benefits of blood pressure and cholesterol control (primarily reduction of macrovascular events, but also microvascular events), and their overall cost effectiveness exceeds that of glycaemic control. Issues with treatment for hypertension include potential side effects of drugs, a potential increased risk of falls and risks of polypharmacy. Nevertheless, the evidence for a blood pressure target of <140/80 mmHg is reasonably strong if it can be achieved safely. In general, we recommend use of an HMG-CoA reductase inhibitor (statin) and an LDL-C target of <100 mg/dL, especially if an individual cannot tolerate a moderate dose of a statin.