- 60 to 69 years: about 15 percent
- 70 to 79 years: about 20 percent
- Over 80 years: 25 percent or more
- Nursing home: up to 30 percent
The frequency of diabetes increases markedly with age. At the same time its clinical significance changes: while in younger patients consequential illnesses in 10 to 30 years must be avoided, in older patients the current quality of life is more strongly in the foreground.
In the 1990s the UKPDS study established the principle: each HbA1c percentage point less reduces diabetes-related complications by about 25 percent. For a 55-year-old with 30 years of life expectancy, this is a clear recommendation for tight control. For an 85-year-old with 5 years of life expectancy, the calculation looks different:
- Long-term effects take years: The reduction of retinopathy, nephropathy and neuropathy only becomes apparent after 10 to 15 years. Many older patients do not have this time.
- Hypoglycemia takes effect immediately: Low blood sugar can lead within minutes to falls, delirium, cardiac arrhythmias — and increase short-term mortality.
- Symptoms of hypoglycemia are atypical in old age: Sweating, trembling and palpitations — the classic warning signs — are often attenuated in older people. The hypoglycemia presents as confusion, a fall or clouding of consciousness.
- Long-term cognitive consequences: Severe hypoglycemia accelerates cognitive deficits and the risk of dementia in old age.
- Autonomic neuropathy: Aggravates the problem — the body’s own warning of low blood sugar is missing.
International guidelines have rethought their approach in recent years. Today a stratified control according to overall condition applies:
- Robust, good life expectancy, low comorbidity: HbA1c target 6.5 to 7.0 percent
- Moderately impaired, several concomitant illnesses: HbA1c target 7.0 to 7.5 percent
- Frail, limited life expectancy, dementia: HbA1c target 7.5 to 8.5 percent, avoidance of hypoglycemia has priority
The principle: the more difficult the starting situation, the looser the target. Not because the diabetes would then be less important — but because the harms of an overly tight target outweigh the benefit.
→ On the frailty assessment that underpins this classification: Frailty syndrome.
Suitable to well suited
- Metformin: The classic basic therapy. Safe and effective as long as the kidney function eGFR is above 30 ml/min. Little risk of hypoglycemia.
- SGLT2 inhibitors (dapagliflozin, empagliflozin, canagliflozin): Approved for diabetes, heart failure in old age and chronic renal insufficiency. Strong cardio- and nephroprotective effects. Caution with dehydration, urogenital infections and the risk of diabetic ketoacidosis.
- GLP-1 agonists (semaglutide, dulaglutide, liraglutide): Weekly or daily injection. Cardioprotective, weight-lowering. In older people who are overweight, a good option. Side effects: nausea, gastrointestinal.
- DPP-4 inhibitors (sitagliptin, linagliptin, vildagliptin): Well tolerated, little risk of hypoglycemia. Moderate effect.
With caution
- Insulin: Often necessary, but to be dosed with particular care in old age. Basal insulin once daily is safer than complex multiple injections.
- Pioglitazone: Effective, but to be avoided in old age because of the risk of edema and fracture — and thus the increased risk of osteoporosis in old age.
To be avoided in frail older people
- Sulfonylureas (glibenclamide, glimepiride): High risk of hypoglycemia. On the PRISCUS list. Particularly problematic in renal insufficiency.
- Glinides: Similar risk of hypoglycemia.
- Alpha-glucosidase inhibitors (acarbose): Gastrointestinal side effects limit tolerability.
→ On the structured review of medications in old age: Polypharmacy in old age and Deprescribing.
Hypoglycemia is the most common and most dangerous acute complication of diabetes therapy in old age. Classic symptoms are often absent. What relatives should know:
- Atypical warning signs: Sudden confusion, unsteady gait, dizziness, visual disturbances, unusual tiredness.
- Falls as a symptom of hypoglycemia: Not every fall investigation thinks of it — but it should. More on the consequences: Falls in old age.
- Nocturnal hypoglycemia: Often unnoticed, it shows itself in the morning through morning confusion, poor sleep, headache.
- Acute response: In a conscious patient: fast-acting carbohydrates — glucose, fruit juice, sugar. In an unconscious patient: emergency doctor, glucagon emergency injection if available.
???? In every fall of an older diabetic, blood sugar measurement belongs in the routine. An unrecognised hypoglycemia is the most common overlooked cause of falls.
→ On the work-up of falls in old age: Falls in old age and Fall prevention.
- Nutrition: Not a strict diabetes diet, but a balanced, protein-rich diet — particularly important in older patients at risk of sarcopenia and to protect against malnutrition in old age.
- Exercise: Strength training and aerobic training improve insulin sensitivity. And protect against sarcopenia, falls and depression in old age.
- Weight management: In overweight, a moderate reduction is sensible; in normal weight or slight underweight, avoid weight reduction — underweight in old age is a risk factor in its own right.
- Foot care: Diabetic neuropathy plus frailty results in a high risk of diabetic feet. Regular inspection, good shoes, in case of problems present to a specialist.
→ On the independent significance of muscle loss: Sarcopenia.
→ On nutrition in old age: Malnutrition in old age.
- Repeated hypoglycemia, even mild
- Unclear falls with existing diabetes — work-up via frailty screening
- HbA1c below 6.5 percent in a frail patient — a reason to review, not a reason to celebrate
- Worsening of kidney function
- New cognitive impairments — possible indications of mild cognitive impairment (MCI)
- Signs of diabetic foot syndrome
- Insulin therapy with uncertainty about everyday management
→ On the structured overall assessment: Geriatric assessment.
