Diabetes and Dementia: The Hidden Link Care Homes Must Know About
New survey data from Alzheimer’s Research UK has revealed a significant gap in public awareness around one of dementia’s most influential risk factors — with profound implications for those working in residential and nursing care.
The charity’s Dementia Attitudes Monitor found that just 39 per cent of people believe it is possible to reduce their risk of developing dementia, while only four per cent of UK adults identified diabetes as a dementia risk factor. Yet research indicates that up to 45 per cent of dementia cases worldwide may be linked to modifiable factors — and diabetes is firmly among them.
Diabetes affects an estimated 5.8 million people in the UK. The condition, which causes blood sugar levels to become dangerously elevated, exists in two main forms. Type 1 is an autoimmune condition, typically developing in early life, in which the body is unable to produce insulin.
Type 2, by far the more common form, occurs when the body either fails to produce sufficient insulin or cannot use it effectively, and is most prevalent in adults over 25. Obesity and being overweight are among the most significant risk factors for Type 2, alongside ethnicity and family history.
The connection between diabetes and dementia risk has been strengthened by a growing body of research. The long-running Whitehall II cohort study, which has followed more than 10,000 British civil servants since the 1980s, found in its 2021 findings that individuals who developed Type 2 diabetes earlier in life were at a heightened risk of developing dementia — and that the younger the onset, the greater that risk.
The Lancet Commission on Dementia Prevention, Intervention and Care has formally identified Type 2 diabetes as a recognised risk factor for the condition.
The mechanisms behind the association are not yet fully understood, but researchers note that diabetes adversely affects cardiovascular health and is linked to raised blood pressure and high cholesterol — both of which independently increase dementia risk.
For care home staff supporting residents living with diabetes, the findings carry practical significance.
Experts agree that effective management of the condition — through healthy eating, physical activity and appropriate medication — represents an important strategy for protecting brain health. People living with Type 1, and many with Type 2, require insulin therapy as part of their care.
Research into the relationship between the two conditions continues. Dr Joyce Huang is currently investigating whether a class of drugs used to treat Type 2 diabetes, known as thiazolidinediones, might also help prevent vascular dementia, by analysing medical records to assess whether patients taking these drugs show a reduced risk.
Separately, Professor Bettina Platt and Dr Zara Franklin at the University of Aberdeen have examined the role of the BACE1 gene, finding it linked to inflammation and cellular stress present in both Alzheimer’s disease and diabetes — offering further clues to the biological connection.
